CN107710839A - Communication means and device - Google Patents

Abstract

The invention discloses a kind of communication means and communicator, this method includes：The first terminal equipment detection very first time shifts to an earlier date TA configured informations, wherein, the first TA configured informations are sent by second terminal equipment, and TA value of the first TA configured informations for indicating the second terminal equipment；The first terminal equipment determines the TA values of the first terminal equipment according to the first TA configured informations detected.Communication means and device disclosed by the invention can reduce the burden and signaling consumption of the network equipment.

Description

Communication method and device Technical Field

The present invention relates to the field of communications, and more particularly, to a communication method and apparatus.

Background

In a Long Term Evolution (LTE) system, a ue implements uplink synchronization with a base station through a closed-loop TA with the base station. Specifically, in the process of randomly accessing the network, the user equipment may generate a preamble sequence and transmit the preamble sequence to the base station. The base station may determine a Time Advance (TA) value of the ue according to the received preamble sequence, and send a Random Access Response (RAR) carrying the TA value to the ue. After receiving the RAR, the ue may perform uplink timing adjustment according to the TA value carried in the RAR, so as to complete uplink synchronization with the base station. In addition, the ue may start a Time Alignment Timer (Time Alignment Timer), and if the ue receives TA update information sent by the base station before the Time Alignment Timer expires, the ue may perform uplink timing update using the TA update information and reset the Time Alignment Timer, where the TA update information may be determined by the base station according to the received uplink information (e.g., Demodulation Reference Signal (DMRS), Sounding Reference Signal (SRS), etc.) sent by the ue; if the ue does not receive the TA update information sent by the base station before the time alignment timer expires, the ue may determine that the uplink is out of synchronization and obtain its TA value by performing the closed-loop TA procedure again.

However, in the above procedure, the base station needs to provide the initial TA value and the TA update information for each user equipment individually, and thus a large amount of signaling overhead is required.

Disclosure of Invention

Embodiments of the present invention provide a communication method and a communication apparatus, which can reduce a burden and signaling overhead of a network device.

In a first aspect, a communication method is provided, including: the method comprises the steps that a first terminal device detects first TA indication information, wherein the first TA indication information is sent by a second terminal device and is used for indicating a TA value of the second terminal device; and the first terminal equipment determines the TA value of the first terminal equipment according to the detected first TA indication information.

In a first possible implementation manner of the first aspect, the determining a TA value of the first terminal device according to the detected first TA indication information includes: and determining the TA value indicated by the detected first TA indication information as the TA value of the first terminal equipment.

With reference to the foregoing possible implementation manners, in a second possible implementation manner of the first aspect, the first TA indication information is further used to indicate a serving cell of the second terminal device; the determining the TA value of the first terminal device according to the detected first TA indication information includes: and if the current serving cell of the first terminal equipment is the same as the serving cell indicated by the first TA indication information, determining the TA value of the first terminal equipment according to the detected first TA indication information.

With reference to the foregoing possible implementation manners, in a third possible implementation manner of the first aspect, before the detecting the first TA indication information, the method further includes: receiving first indication information sent by a network device, where the first indication information is used to indicate that the first terminal device is a first type of terminal device, where the first type of terminal device is a terminal device that acquires a TA value from TA indication information sent by a second type of terminal device, and the second type of terminal device is a terminal device that acquires a TA value from the network device.

With reference to the foregoing possible implementation manners, in a fourth possible implementation manner of the first aspect, the receiving the first indication information sent by the network device includes: and receiving the first indication information sent by the network equipment in the random access process.

With reference to the foregoing possible implementation manners, in a fifth possible implementation manner of the first aspect, the method further includes: if the first terminal equipment is out of synchronization in an uplink way, the TA value of the first terminal equipment is obtained from the network equipment; and continuously detecting the first TA indication information.

With reference to the foregoing possible implementation manners, in a sixth possible implementation manner of the first aspect, before the detecting the first TA indication information, the method further includes: detecting second TA indication information, which is transmitted by a third terminal device determined to be a second type of terminal device and is used for indicating a TA value of the third terminal device, when initially accessing the network device or switching from a sleep state to a connected state; and if the second TA indication information is detected within a preset time period, determining that the first terminal equipment is the first type of terminal equipment.

With reference to the foregoing possible implementation manners, in a seventh possible implementation manner of the first aspect, the method further includes: if the first terminal equipment is out of synchronization in an uplink way, the TA value of the first terminal equipment is obtained from the network equipment; determining that the first terminal device is changed from the first type of terminal device to the second type of terminal device.

With reference to the foregoing possible implementation manners, in an eighth possible implementation manner of the first aspect, the detecting the first TA indication information includes: the first TA indication information is detected on the D2D broadcast channel.

With reference to the foregoing possible implementation manners, in a ninth possible implementation manner of the first aspect, before the detecting the first TA indication information, the method further includes: receiving second indication information sent by the network equipment, wherein the second indication information is used for indicating at least one of transmission resources, transmission power and transmission modes of the first TA indication information; the detecting the first TA indication information includes: and detecting the first TA indication information according to the second indication information.

In a second aspect, another communication method is provided, including: the second terminal equipment acquires the TA value of the second terminal equipment from the network equipment; the second terminal device sends first TA indication information to the first terminal device, wherein the first TA indication information is used for indicating a TA value of the second terminal device.

In a first possible implementation manner of the second aspect, the first TA indication information is further used for indicating a serving cell of the second terminal device.

With reference to the foregoing possible implementation manners, in a second possible implementation manner of the second aspect, before the obtaining, by the network device, the TA value of the second terminal device, the method further includes: and receiving first indication information sent by the network equipment, wherein the first indication information is used for indicating that the second terminal equipment is the second type terminal equipment, and the second type terminal equipment is the terminal equipment which acquires the TA value from the network equipment.

With reference to the foregoing possible implementation manners, in a third possible implementation manner of the second aspect, the receiving the first indication information sent by the network device includes: and receiving the first indication information sent by the network equipment in the random access process.

With reference to the foregoing possible implementation manners, in a fourth possible implementation manner of the second aspect, before the obtaining, by the network device, the TA value of the second terminal device, the method further includes: detecting second TA indication information, which is sent by a third terminal device determined to be a second type of terminal device, when initially accessing the network device or switching from a sleep state to a connected state, and is used for indicating a TA value of the third terminal device; and if the second TA indication information is not detected within the preset time period, determining that the second terminal equipment is the second type of terminal equipment.

With reference to the foregoing possible implementation manners, in a fifth possible implementation manner of the second aspect, the sending the first TA indication information to the first terminal device includes: the first TA indication information is transmitted on a D2D broadcast channel.

With reference to the foregoing possible implementation manners, in a sixth possible implementation manner of the second aspect, before the sending the first TA indication information to the first terminal device, the method further includes: receiving second indication information sent by the network equipment, wherein the second indication information is used for indicating at least one of transmission resources, transmission power and transmission modes of the first TA indication information; the sending of the first TA indication information to the first terminal device includes: and sending first TA indication information to the first terminal equipment according to the second indication information.

In a third aspect, another communication method is provided, including: determining transmission resources of TA indication information, wherein the TA indication information is transmitted to a first type of terminal equipment by a second type of terminal equipment, and the TA indication information transmitted by the second type of terminal equipment is used for indicating a TA value of the second type of terminal equipment; and sending second indication information, wherein the second indication information is used for indicating the transmission resource of the TA indication information.

In a first possible implementation manner of the third aspect, the sending the second indication information includes: the second indication information is transmitted in a broadcast form.

With reference to the foregoing possible implementation manners, in a second possible implementation manner of the third aspect, the second indication information is further used to indicate a transmission power of the TA indication information; before the sending the second indication information, the method further comprises: determining the expected transmission distance of the TA indication information according to the TA adjustment granularity; and determining the transmitting power of the TA indication information according to the expected transmission distance.

With reference to the foregoing possible implementation manners, in a third possible implementation manner of the third aspect, the method further includes: determining that the first terminal equipment is the first type of terminal equipment or the second type of terminal equipment; and sending first indication information to the first terminal device, wherein the first indication information is used for indicating that the first terminal device is the terminal device of the first type or the terminal device of the second type.

With reference to the foregoing possible implementation manners, in a fourth possible implementation manner of the third aspect, the sending the first indication information to the first terminal device includes: and sending the first indication information to the first terminal equipment in the random access process of the first terminal equipment.

With reference to the foregoing possible implementation manners, in a fifth possible implementation manner of the third aspect, the method further includes: receiving uplink information sent by second terminal equipment; determining the uplink desynchronizing of the second terminal equipment according to the received uplink information; and sending third indication information to the second terminal equipment, wherein the third indication information is used for indicating the uplink desynchronization of the second terminal equipment.

In a fourth aspect, another communication method is provided, including: determining that a first terminal device is a first type terminal device or a second type terminal device, wherein the second type terminal device is a terminal device which acquires a TA value from a network device, and the first type terminal device is a terminal device which acquires the TA value from the detected TA indication information sent by the second type terminal device; and sending first indication information, wherein the first indication information is used for indicating that the first terminal equipment is the terminal equipment of the first type or the terminal equipment of the second type.

In a first possible implementation manner of the fourth aspect, the sending the first indication information includes: and sending the first indication information in the random access process of the first terminal equipment.

In a fifth aspect, a communication apparatus is provided, including: a detecting unit, configured to detect first TA indication information, where the first TA indication information is sent by a second terminal device, and the first TA indication information is used to indicate a TA value of the second terminal device; and the determining unit is used for determining the TA value of the first terminal equipment according to the first TA indicating information detected by the detecting unit.

In a first possible implementation manner of the fifth aspect, the first TA indication information is further used for indicating a serving cell of the second terminal device; the determining unit is specifically configured to determine the TA value of the first terminal device according to the first TA indication information detected by the detecting unit, if the current serving cell of the first terminal device is the same as the serving cell indicated by the first TA indication information.

With reference to the foregoing possible implementation manners, in a second possible implementation manner of the fifth aspect, the determining unit is specifically configured to determine the TA value indicated by the first TA indication information detected by the detecting unit as the TA value of the first terminal device.

With reference to the foregoing possible implementation manners, in a third possible implementation manner of the fifth aspect, the apparatus further includes: a first receiving unit, configured to receive first indication information sent by a network device before the detecting unit detects the first TA indication information, where the first indication information is used to indicate that the first terminal device is a first type of terminal device, the first type of terminal device is a terminal device that obtains a TA value from TA indication information sent by a second type of terminal device, and the second type of terminal device is a terminal device that obtains a TA value from the network device.

With reference to the foregoing possible implementation manners, in a fourth possible implementation manner of the fifth aspect, the first receiving unit is specifically configured to receive the first indication information sent by the network device in a random access process.

With reference to the foregoing possible implementation manners, in a fifth possible implementation manner of the fifth aspect, the apparatus further includes: a first obtaining unit, configured to obtain a TA value of the first terminal device from the network device if the first terminal device is out of synchronization in an uplink direction; the detecting unit is further configured to continue detecting the first TA indication information.

With reference to the foregoing possible implementation manners, in a sixth possible implementation manner of the fifth aspect, the detecting unit is further configured to detect, when initially accessing the network device or switching from the sleep state to the connected state, second TA indication information, where the second TA indication information is sent by a third terminal device that is determined to be a second type of terminal device, and the second TA indication information is used to indicate a TA value of the third terminal device; the determining unit is further configured to determine that the first terminal device is a first type of terminal device if the detecting unit detects the second TA indication information within a preset time period.

With reference to the foregoing possible implementation manners, in a seventh possible implementation manner of the fifth aspect, the apparatus further includes: a second obtaining unit, configured to obtain, from the network device, the TA value of the first terminal device if the first terminal device is out of synchronization in the uplink.

With reference to the foregoing possible implementation manners, in an eighth possible implementation manner of the fifth aspect, the detecting unit is specifically configured to: the first TA indication information is detected on the D2D broadcast channel.

With reference to the foregoing possible implementation manners, in a ninth possible implementation manner of the fifth aspect, the apparatus further includes: a second receiving unit, configured to receive second indication information sent by the network device before the detecting unit detects the first TA indication information, where the second indication information is used to indicate at least one of a transmission resource, a transmission power, and a transmission manner of the first TA indication information; the detecting unit is specifically configured to detect the first TA indication information according to the second indication information received by the second receiving unit.

With reference to the foregoing possible implementation manners, in a tenth possible implementation manner of the fifth aspect, the apparatus is the first terminal device.

In a sixth aspect, another communication apparatus is provided, including: an obtaining unit, configured to obtain a TA value of a second terminal device from a network device; a sending unit, configured to send first TA indication information to the first terminal device, where the first TA indication information is used to indicate the TA value acquired by the acquiring unit.

In a first possible implementation manner of the sixth aspect, the first TA indication information is further used for indicating a serving cell of the second terminal device.

With reference to the foregoing possible implementation manners, in a second possible implementation manner of the sixth aspect, the apparatus further includes: a first receiving unit, configured to receive first indication information sent by a network device before the obtaining unit obtains a TA value of a second terminal device from the network device, where the first indication information is used to indicate that the second terminal device is a second type terminal device, and the second type terminal device is a terminal device that obtains the TA value from the network device.

With reference to the foregoing possible implementation manners, in a third possible implementation manner of the sixth aspect, the first receiving unit is specifically configured to receive the first indication information sent by the network device in a random access procedure.

With reference to the foregoing possible implementation manners, in a fourth possible implementation manner of the sixth aspect, the apparatus further includes: a detecting unit, configured to detect second TA indication information when initially accessing the network device or switching from a sleep state to a connection state before the acquiring unit acquires the TA value of the second terminal device from the network device, where the second TA indication information is sent by a third terminal device that has been determined to be the second type of terminal device, and the second TA indication information is used for indicating the TA value of the third terminal device; and a determining unit, configured to determine that the second terminal device is a second type of terminal device if the detecting unit does not detect the second TA indication information within a preset time period.

With reference to the foregoing possible implementation manners, in a fifth possible implementation manner of the sixth aspect, the sending unit is specifically configured to send the first TA indication information on a D2D broadcast channel.

With reference to the foregoing possible implementation manners, in a sixth possible implementation manner of the sixth aspect, the apparatus further includes: a second receiving unit, configured to receive second indication information sent by the network device before the sending unit sends the first TA indication information to the first terminal device, where the second indication information is used to indicate at least one of a transmission resource, a transmission power, and a transmission mode of the first TA indication information; the sending unit is specifically configured to send the first TA indication information to the first terminal device according to the second indication information received by the second receiving unit.

With reference to the foregoing possible implementation manners, in a seventh possible implementation manner of the sixth aspect, the apparatus is the second terminal device.

In a seventh aspect, another communication apparatus is provided, including: a determining unit, configured to determine a transmission resource of TA indication information, where the TA indication information is sent by a second type of terminal device to a first type of terminal device, and the TA indication information is used to indicate a TA value of the second type of terminal device, the second type of terminal device is a terminal device that obtains the TA value from a network device, and the first type of terminal device is a terminal device that obtains the TA value from the TA indication information sent by the second type of terminal device; a sending unit, configured to send second indication information, where the second indication information is used to indicate a transmission resource of the TA indication information.

In a first possible implementation manner of the seventh aspect, the sending unit is specifically configured to send the second indication information in a broadcast form.

With reference to the foregoing possible implementation manners, in a second possible implementation manner of the seventh aspect, the second indication information is further used to indicate a transmission power of the TA indication information; the determining unit is further configured to determine a desired transmission distance of the TA indication information according to the TA adjustment granularity and determine a transmit power of the TA indication information according to the desired transmission distance before the sending unit sends the second indication information.

With reference to the foregoing possible implementation manners, in a third possible implementation manner of the seventh aspect, the determining unit is further configured to determine that the first terminal device is the terminal device of the first type or the terminal device of the second type; the sending unit is further configured to send first indication information to the first terminal device, where the first indication information is used to indicate the type of the first terminal device determined by the determining unit.

With reference to the foregoing possible implementation manners, in a fourth possible implementation manner of the seventh aspect, the sending unit is specifically configured to send the first indication information to the first terminal device in a random access procedure of the first terminal device.

With reference to the foregoing possible implementation manners, in a fifth possible implementation manner of the seventh aspect, the apparatus further includes: a receiving unit, configured to receive uplink information sent by a second terminal device; the determining unit is further configured to determine that the second terminal device is out of synchronization in an uplink manner according to the uplink information received by the receiving unit; the sending unit is further configured to send third indication information to the second terminal device, where the third indication information is used to indicate the uplink out-of-synchronization of the second terminal device determined by the determining unit.

With reference to the foregoing possible implementation manners, in a sixth possible implementation manner of the seventh aspect, the apparatus is the network device.

In an eighth aspect, there is provided another communication apparatus comprising: a determining unit, configured to determine that a first terminal device is a first type terminal device or a second type terminal device, where the second type terminal device is a terminal device that obtains a TA value from a network device, and the first type terminal device is a terminal device that obtains a TA value from TA indication information sent by the detected second type terminal device; a sending unit, configured to send first indication information, where the first indication information is used to indicate the type of the first terminal device determined by the determining unit.

In a first possible implementation manner of the eighth aspect, the sending unit is specifically configured to send the first indication information in a random access procedure of the first terminal device.

With reference to the foregoing possible implementation manners, in a second possible implementation manner of the eighth aspect, the apparatus is the network device.

Based on the above technical solution, in the communication method and apparatus provided in the embodiments of the present invention, the first terminal device detects the first TA indication information sent by the second terminal device, where the first TA indication information is used to indicate a TA value of the second terminal device, and the first terminal device determines its TA value according to the detected first TA indication information, and does not need to directly interact with the network device.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments of the present invention or in the description of the prior art will be briefly described below, and it is obvious that the drawings described below are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a schematic diagram of a communication system to which embodiments of the present invention may be applied.

Fig. 2 is a diagram of competing transmission units in the communication system shown in fig. 1.

Fig. 3 is a schematic flow chart of a communication method provided by the embodiment of the invention.

Fig. 4 is a schematic diagram of an application scenario of an embodiment of the present invention.

Fig. 5 is a schematic diagram of another application scenario of an embodiment of the present invention.

Fig. 6 is a schematic flow chart of another communication method provided by the embodiment of the invention.

Fig. 7 is a schematic flow chart of another communication method provided by the embodiment of the invention.

Fig. 8 is a schematic flow chart of another communication method provided by the embodiment of the invention.

Fig. 9 is a schematic flow chart of another communication method provided by the embodiment of the invention.

Fig. 10 is a schematic flow chart of another communication method provided by the embodiment of the invention.

Fig. 11 is a schematic block diagram of a communication device provided by an embodiment of the present invention.

Fig. 12 is a schematic block diagram of another communication device provided by an embodiment of the present invention.

Fig. 13 is a schematic block diagram of another communication device provided by an embodiment of the present invention.

Fig. 14 is a schematic block diagram of another communication device provided by an embodiment of the present invention.

Fig. 15 is a schematic block diagram of another communication device provided by an embodiment of the present invention.

Fig. 16 is a schematic block diagram of another communication device provided by an embodiment of the present invention.

Fig. 17 is a schematic block diagram of another communication device provided by an embodiment of the present invention.

Fig. 18 is a schematic block diagram of another communication device provided by an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, not all, embodiments of the present invention. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, shall fall within the scope of protection of the present invention.

It should be understood that the technical solutions of the embodiments of the present invention can be applied to various communication systems, for example: a Global System for Mobile communications (GSM) System, a Code Division Multiple Access (CDMA) System, a Wideband Code Division Multiple Access (WCDMA) System, a General Packet Radio Service (GPRS), a Long Term Evolution (Long Term Evolution, LTE) System, an LTE Frequency Division Duplex (FDD) System, an LTE Time Division Duplex (TDD), a Universal Mobile Telecommunications System (UMTS), a Worldwide Interoperability for Microwave Access (WiMAX) communication System, a future 5G communication System, and the like.

It should be further understood that the technical solution of the embodiment of the present invention may also be applied to various communication systems based on non-orthogonal Multiple Access technologies, such as a Sparse Code Multiple Access (SCMA) system, where the SCMA may also be referred to as other names in the communication field; further, the technical solution of the embodiment of the present invention may be applied to a Multi-Carrier transmission system using a non-Orthogonal multiple access technology, for example, an Orthogonal Frequency Division Multiplexing (OFDM) using a non-Orthogonal multiple access technology, a Filter Bank Multi-Carrier (FBMC), a General Frequency Division Multiplexing (GFDM), a Filtered Orthogonal Frequency Division Multiplexing (F-OFDM) system, and the like.

It should also be understood that, in the embodiments of the present invention, a terminal device may communicate with one or more core networks via a Radio Access Network (RAN), and may be referred to as an Access terminal, a User Equipment (UE), a subscriber unit, a subscriber station, a mobile station, a remote terminal, a mobile device, a User terminal, a wireless communication device, a User agent, or a User Equipment. An access terminal may be a cellular telephone, a cordless telephone, a Session Initiation Protocol (SIP) phone, a Wireless Local Loop (WLL) station, a Personal Digital Assistant (PDA), a handheld device with Wireless communication capability, a computing device or other processing device connected to a Wireless modem, a vehicle mounted device, a wearable device, a terminal device in a future 5G Network or a terminal device in a future evolved Public Land Mobile Network (PLMN), etc.

It should also be understood that, in the embodiment of the present invention, the network device may be used to communicate with the terminal device, and the network device may be a Base Transceiver Station (BTS) in a GSM system or a CDMA system, a Base Station (NodeB, NB) in a WCDMA system, an evolved Node B (eNB or eNodeB) in an LTE system, or a relay Station, an access point, a vehicle-mounted device, a wearable device, a network-side device in a future 5G network, or a network device in a future evolved PLMN network, and the like.

Existing cellular communication systems, such as GSM, WCDMA, LTE, etc., support communications primarily for voice and data communications. Generally, a conventional base station supports a limited number of connections and is easy to implement.

The next generation mobile Communication system will support not only conventional Communication but also Machine to Machine (M2M) Communication, or Machine Type Communication (MTC) Communication. By the year 2020, MTC devices connected to the network are predicted to reach 500 to 1000 billion, which is far beyond the number of connections at present. For M2M type services, the requirements for the network are very different due to the wide variety of services. In general, there are several requirements as follows: (I) reliable transmission, but not sensitive to delay; (II) low latency, high reliability transmission.

And the method is easy to process for reliable transmission and delay insensitive services. However, for low-delay, high-reliability transmission-class services, not only short transmission delay but also reliability is required, such as Vehicle-to-Vehicle (V2V) services. If the transmission is unreliable, the transmission delay is too large due to retransmission, and the requirement cannot be met.

Due to the large number of connections, there is a great difference between future wireless communication systems and existing communication systems. A large number of connections requires more resources to be consumed for accessing the terminal device and more resources to be consumed for the transmission of scheduling signaling related to the data transmission of the terminal device.

FIG. 1 is a block diagram of a system 100 to which embodiments of the present invention may be applied. The system 100 includes a network device 102 and a plurality of terminal devices 104 located within a coverage area of the network device 102, wherein the network device 102 can be connected to the plurality of terminal devices via wireless connections or wired connections or other means, respectively, and the network device 102 can support simultaneous transmission of a plurality of cellular carriers. Fig. 1 exemplarily shows one network device and six terminal devices, alternatively, the system 100 may include a plurality of network devices and each network device may include other numbers of terminal devices within the coverage area, which is not limited in this embodiment of the present invention.

The network in the embodiment of the present invention may refer to a PLMN, a D2D network, an M2M network, or other networks, fig. 1 is a simplified schematic diagram for example, and the network may further include other network devices, which are not shown in fig. 1.

In order to solve a large amount of MTC services in a future network and satisfy low-latency and highly reliable service transmission, the network device 102 in the system 100 may adopt an authorization-Free (Grant Free) transmission scheme, which may be suitable for uplink data transmission. In the authorization-free transmission mechanism, the terminal equipment does not need to request the network equipment to allocate transmission resources in a scheduling request mode, but directly contends for the resources and transmits uplink data, so that the system signaling overhead can be reduced and the transmission delay can be reduced.

The unlicensed transmission can be understood as any one or more of the following meanings, or as a combination of some technical features of the various meanings:

1. the unlicensed transmission may refer to: the network equipment allocates and informs the terminal equipment of a plurality of transmission resources in advance; when the terminal equipment has the requirement of uplink data transmission, selecting at least one transmission resource from a plurality of transmission resources pre-allocated by the network equipment, and sending uplink data by using the selected transmission resource; and the network equipment detects the uplink data sent by the terminal equipment on at least one transmission resource in the plurality of pre-allocated transmission resources. The detection may be blind detection, or detection according to a certain control field in uplink data, or detection in other manners.

The blind detection can be understood as the detection of data that may arrive without predicting whether data arrives. The blind detection may also be understood as a detection without an explicit signaling indication.

2. The unlicensed transmission may refer to: the network device pre-allocates and informs the terminal device of a plurality of transmission resources, so that when the terminal device has a requirement for uplink data transmission, at least one transmission resource is selected from the plurality of transmission resources pre-allocated by the network device, and the selected transmission resource is used for transmitting uplink data.

3. The unlicensed transmission may refer to: the terminal equipment acquires information of a plurality of pre-allocated transmission resources, selects at least one transmission resource from the plurality of transmission resources when uplink data transmission is required, and transmits the uplink data by using the selected transmission resource. The terminal device may obtain the information of the multiple transmission resources in multiple ways, for example, a mapping relationship between the terminal device and the transmission resources may be defined in a protocol, or indicated by a network device through an instruction, and so on.

4. The unlicensed transmission may refer to: the method for realizing uplink data transmission of the terminal equipment can be realized without dynamic scheduling of the network equipment, and the dynamic scheduling can be a scheduling mode that the network equipment needs to indicate transmission resources of uplink data transmission of the terminal equipment every time through signaling. Alternatively, the transmission resource may be one or more transmission time units of transmission resources after the time when the terminal device receives the signaling. One TTI may refer to a minimum Time unit for one Transmission, such as a TTI (Transmission Time Interval), and may be 1ms, or may be a predetermined TTI. Alternatively, implementing uplink data transmission of a terminal device may be understood as allowing data of two or more terminal devices to be transmitted on the same time-frequency resource.

5. The unlicensed transmission may refer to: the terminal equipment carries out uplink data transmission without authorization of the network equipment. The grant may refer to a terminal device sending an uplink scheduling request to a network device, and the network device sending an uplink grant (UL grant) to the terminal device after receiving the scheduling request, where the uplink grant is used to indicate an uplink transmission resource allocated to the terminal device.

6. The unlicensed transmission may refer to: a contention transmission mode, specifically, may refer to that a plurality of terminal devices perform uplink data transmission simultaneously on the same pre-allocated time-frequency resource without requiring a network device to perform authorization.

Optionally, the data may include service data or signaling data.

In the unlicensed transmission scheme, the transmission resources may include, but are not limited to, a combination of one or more of the following: time domain resources such as radio frames, subframes, symbols, etc.; frequency domain resources such as subcarriers, resource blocks, etc.; spatial domain resources such as transmit antennas, beams, etc.; code domain resources, such as Sparse Code Multiple Access (SCMA) codebook groups, Low Density Signature (LDS) groups, CDMA Code groups, and the like; and (4) uplink pilot frequency resources.

The transmission resources as above may be transmitted according to control mechanisms including, but not limited to: uplink power control, such as uplink transmit power upper limit control; setting a modulation coding mode, such as the size of a transmission block, a code rate, a modulation order and the like; a retransmission mechanism, such as Hybrid Automatic Repeat Request (HARQ), etc.

In the unlicensed Transmission mechanism, at least one Contention Access Region (CAR) is defined in a time-frequency domain, where the CAR may refer to a time-frequency domain used for unlicensed Transmission, different CARs may respectively correspond to different time-frequency resources, and each CAR may further include at least one Contention Transmission Unit (CTU), and accordingly, the CAR may also be referred to as a CTU Access Region. The CTU may be a basic transmission resource unit of the unlicensed transmission, and may be a combination of at least one of time, frequency, code and pilot resources, for example, the CTU may refer to a transmission resource formed by a combination of time, frequency and code domain resources, or may refer to a transmission resource formed by a combination of time, frequency and pilot resources, or may refer to a transmission resource formed by a combination of time, frequency, code domain and pilot resources, but the embodiment of the present invention is not limited thereto. A technical solution of unlicensed Transmission is given in patent application No. PCT/CN2014/073084, entitled "System and Method for Uplink Grant-free Transmission Scheme", where Transmission resources may be divided into different CTUs, each CTU may be allocated a set of codes, the allocated set of codes may be a set of CDMA codes, or may be an SCMA codebook set or an LDS set or a signature set, and optionally, each code may correspond to a set of pilots.

After accessing the network device 102, the terminal device 104 may report its capability information to the network device 102, where the capability information may include information indicating whether the terminal device has the capability of unauthorized transmission. In this way, the network device 102 may communicate with the terminal device by using an authorization-free transmission mechanism or a conventional request-authorization mechanism according to the capability information reported by each terminal device. Optionally, the network device 102 may notify the terminal device of necessary information for the unlicensed transmission, for example, the network device 102 may instruct the terminal device to perform the unlicensed transmission, send search space information, CAR information, CTU information, modulation and coding scheme information, and the like to the terminal device, where each terminal device is mapped to one or more CTUs, and the mapping rule may be predefined or configured by the network device. The terminal device may select a code and a pilot in a pilot group corresponding to the code for uplink transmission, which is not limited in this embodiment of the present invention.

The contents of PCT/CN2014/073084 may also be understood as being incorporated by reference as part of the contents of the embodiments of the present invention, and for brevity, will not be described herein again.

It should also be understood that the embodiment of the present invention is mainly applied to the scenarios of the unlicensed transmission shown in fig. 1 and fig. 2, but may also be applied to other communication systems besides fig. 1, and the embodiment of the present invention is not limited thereto.

Fig. 2 exemplarily shows four CARs 1002-1008, wherein the system available bandwidth is divided into a plurality of different time-frequency regions, each CAR occupies different Resource blocks, wherein optionally the number of Resource blocks occupied by each CAR may be predefined, e.g. Resource blocks, RBs) 1-4 of the frequency band occupied by CAR 1002. As shown in fig. 2, each CAR may be further divided into at least one CTU, where each CTU is a combination of a specific time, frequency, signature, and pilot, and each CAR in fig. 2 corresponds to the same CTU mapping relationship, and here, for illustration, the mapping relationships of four CARs are shown from different perspectives, respectively, but the embodiment of the present invention is not limited thereto. As shown in fig. 2, each CAR supports 6 signatures (S1-S6), each signature may correspond to 6 pilots, thus forming 36 pilots (P1-P36) corresponding to 36 CTUs, but the embodiment of the invention is not limited thereto.

It should be understood that fig. 2 exemplarily shows four CARs and each CAR includes 36 CTUs, but embodiments of the present invention may also include other numbers of CARs and each CAR may include other numbers of CTUs, which are not limited by the embodiments of the present invention.

Fig. 3 illustrates a communication method 200 provided by an embodiment of the invention. The method 200 may be performed by a first terminal device.

S210, detecting first TA indication information, where the first TA indication information is sent by a second terminal device, and the first TA indication information is used for indicating a TA value of the second terminal device.

In the embodiment of the present invention, a plurality of terminal devices in a network are divided into two types, that is, a first type terminal device and a second type terminal device, where the second type terminal device obtains its TA value from the network device, and sends TA indication information indicating its TA value to the first type terminal device in a unicast, multicast or broadcast manner. The first type terminal device detects TA indicating information sent by the second type terminal device, and determines the TA value of the first type terminal device according to the detected TA indicating information.

The first terminal device may determine itself to be a first type of terminal device or a second type of terminal device. If the first terminal device determines that the first terminal device is the first type of terminal device, the first terminal device may monitor TA indication information sent by the second type of terminal device, where the second terminal device may be the second type of terminal device, which is not limited in the embodiment of the present invention.

Optionally, the first terminal device may perform blind detection, that is, the first terminal device performs detection without knowing a transmitting end, and at this time, the first terminal device may not know in advance which terminal device the second terminal device is specifically, and further, optionally, the first terminal device may detect the first TA indication information by using a specific transmission resource, for example, continuously or periodically detect the first TA indication information on the D2D transmission resource. In this embodiment of the present invention, the transmission resource may be a combination of at least one resource of time, frequency, space, code, and pilot, and the specific transmission resource may be predefined, or may be obtained from a signaling sent by a network device, or obtained in another manner, which is not limited in this embodiment of the present invention.

S220, determining a TA value of the first terminal device according to the detected first TA indication information.

If the first terminal device detects first TA indication information sent by a certain terminal device of the second type (i.e., a second terminal device), the first terminal device may determine its TA value according to the detected first TA indication information, where detecting the first TA indication information may indicate that the first TA indication information is successfully received, but the embodiment of the present invention is not limited thereto. Specifically, if the first terminal device has previously acquired a TA value and acquired uplink synchronization with the network device, the first terminal device may update the TA value of the first terminal device according to the detected first TA indication information; if the first terminal device does not acquire any TA value before, the current TA value of the first terminal device may be determined as the TA value indicated by the detected first TA indication information, and uplink synchronization with the network device is obtained through the TA value, but the embodiment of the present invention is not limited thereto.

Therefore, in the communication method provided in the embodiment of the present invention, the first terminal device detects the first TA indication information sent by the second terminal device, where the first TA indication information is used to indicate a TA value of the second terminal device, and the first terminal device determines the TA value of itself according to the detected first TA indication information, without directly interacting with the network device.

In the embodiment of the present invention, the terminal device of the second type may obtain its TA value through signaling interaction with the network device. As an optional embodiment, the terminal device of the second type may obtain its TA value from the network device in a closed-loop manner, for example, the terminal device of the second type may send uplink information to the network device, the network device may obtain an uplink synchronization deviation between the terminal device and the network device by measuring the uplink information, and send a TA command to the terminal device, where the TA command is used to indicate the TA value of the terminal device, and specifically, the TA command may include a current TA value of the terminal device, an adjustment amount of the TA value, or an adjustment step number of the TA value, and so on, but the embodiment of the present invention is not limited thereto.

The first type of terminal equipment does not need to interact with the network equipment directly, but obtains the TA value of the first type of terminal equipment from the second type of terminal equipment, so that compared with the prior art that each terminal equipment needs to obtain the TA value of the second type of terminal equipment through direct interaction with the network equipment, the embodiment of the invention can reduce the burden and signaling overhead of the network equipment. In addition, in the embodiment of the present invention, the terminal device of the first type may obtain its TA value in an open-loop manner, and compared with the terminal device in the prior art that obtains its TA value in a closed-loop manner, the signaling overhead of the system may be further reduced.

For convenience of description, in the following description, a first type of terminal device is simply referred to as a coarse TA device, and a second type of terminal device is simply referred to as a fine TA device, but the embodiments of the present invention are not limited to this name.

As an alternative embodiment, S220, determining a TA value of the first terminal device according to the detected first TA indication information includes:

and determining the TA value indicated by the detected first TA indication information as the TA value of the first terminal equipment.

Optionally, the first terminal device may also determine its own TA value in other manners, for example, the first terminal device may perform an operation on the TA value indicated by the detected first TA indication information, for example, add an adjustment amount to obtain its own TA value, which is not limited in this embodiment of the present invention.

As shown in fig. 4, a network device may provide a service for a plurality of terminal devices, where at least one terminal device of the plurality of terminal devices may be a fine TA device, and the remaining terminal devices are coarse TA devices. Fig. 4 exemplarily shows three fine TA devices: the system comprises a terminal A, a terminal B and a terminal C, wherein the three fine TA devices can obtain the current TA values of the devices through signaling interaction with the network device, and broadcast TA indication information for indicating the current TA values of the devices. The coarse TA device may obtain its current TA value by monitoring the TA indication information. For example, a coarse TA device located in the broadcast range of terminal a may receive TA indication information sent by terminal a, and optionally determine a TA value indicated by the received TA indication information as its current TA value, so that terminal a and the coarse TA device located in the broadcast range of terminal a may use the same TA value, but the embodiment of the present invention is not limited thereto.

Optionally, if a terminal device is not located in the broadcast range of any fine TA device served by the network device, for example, the terminal D is located outside the broadcast ranges of the terminal a, the terminal B, and the terminal C, the terminal device cannot monitor the TA indication information, and at this time, although the terminal D is a coarse TA device, the terminal D may still obtain its TA value through signaling interaction with the network device, but the embodiment of the present invention is not limited thereto.

Optionally, as another optional embodiment, if one coarse TA device is located within the broadcast range of at least two fine TA devices at the same time, for example, the terminal E is located within the broadcast range of the terminal B and the terminal C at the same time, and therefore, the TA indication information sent by the terminal B and the terminal C may be monitored, at this time, the terminal E may determine the target TA indication information from the two monitored TA indication information, and determine its current TA value according to the target TA indication information. Alternatively, the terminal E may determine any one of the two pieces of TA indication information as the target TA indication information, or the terminal E may perform decoding processing on the two pieces of monitored TA indication information, and determine the successfully decoded TA indication information as the target TA indication information. Optionally, if the two pieces of TA indication information monitored by the terminal E are both decoded successfully, the terminal E may determine any one of the TA indication information or the TA indication information with higher received power as the target TA indication information, which is not limited in this embodiment of the present invention. Optionally, if interference is generated between the two pieces of TA indication information monitored by the terminal E, so that the terminal E cannot correctly decode any one of the TA indication information, the terminal E may obtain its current TA value through signaling interaction with the network device, but the embodiment of the present invention is not limited thereto.

In this embodiment of the present invention, the fine TA device may periodically or triggerably transmit TA indication information, and the fine TA device may transmit the TA indication information in a unicast, multicast, or Broadcast manner, and further, the fine TA device may transmit the TA indication information in a D2D manner, for example, the fine TA device may transmit the TA indication information on a Physical bypass Broadcast Channel (PSBCH) or other D2D Broadcast channels, but the embodiment of the present invention is not limited thereto. The TA indication information may be used to indicate a current TA value of the fine TA device, where the TA indication information may explicitly or implicitly indicate the current TA value of the fine TA device, for example, the TA indication information may include the current TA value of the fine TA device or adjustment information of the TA value of the fine TA device, for example, a change amount or a change step number of the current TA value of the fine TA device with respect to a last TA value or a reference value, but the embodiment of the present invention is not limited thereto. In addition, one or more of transmission resources, transmission power, and transmission modes (for example, modulation and coding modes, the number of antennas, and the like) adopted when the fine TA device sends the TA indication information may be predefined, or may be indicated by the network device through signaling, which is not limited in this embodiment of the present invention.

In this embodiment of the present invention, the first terminal device may periodically or continuously detect TA indication information sent by the fine TA device, and optionally, S210 detects the TA first indication information, where the detecting includes: the first TA indication information is detected on the D2D broadcast channel.

In the implementation of the present invention, the first terminal device may determine its type as the first type or the second type in a variety of ways. For example, the type of the first terminal device may be predefined, for example, determined by whether the first terminal device has a capability of being a fine TA device, or the type of the first terminal device may be configured by a network device, or the type of the first terminal device may be determined by whether the first terminal device can detect TA indication information sent by a second type of terminal device within a time period of a specific time duration, which is not limited in this embodiment of the present invention. As an alternative embodiment, before S210, the method 200 includes:

receiving first indication information sent by a network device, where the first indication information is used to indicate that the first terminal device is a first type of terminal device, where the first type of terminal device is a terminal device that acquires a TA value from TA indication information sent by a second type of terminal device, and the second type of terminal device is a terminal device that acquires a TA value from the network device.

At this time, the first terminal device may determine that it is the first type of terminal device according to the first indication information, that is, determine that the first terminal device is the coarse TA device. The network device may send the first indication information to the first end device in a unicast manner, or the network device may multicast the first indication information to a plurality of end devices belonging to the first type, or may broadcast the first indication information within the network. In addition, the network device may send the first indication information to the first terminal device during or after the first terminal device initially establishes a connection with the network device, which is not limited in the embodiment of the present invention. As an optional embodiment, the receiving the first indication information sent by the network device includes: and receiving the first indication information sent by the network equipment in the random access process.

For example, the first indication information may be carried in a random access response, and at this time, the first indication information may further be used to indicate an initial TA value of the first terminal device, but the embodiment of the present invention is not limited thereto. Table 1 shows an exemplary format of a random access response, which may include a reserved field, a type indication field, which may be used to indicate a type of a terminal device, and a Timing Advance Command (TAC) field, which may be used to indicate a TA value. Optionally, the type indication field may occupy 1 bit, where a value of the bit being 1 indicates that the terminal device is the second type of terminal device, and a value of the bit being 0 indicates that the terminal device is the first type of terminal device; or vice versa. Optionally, as another embodiment, the random access response may carry the type indication field only when the terminal device is a terminal device of a first type or a terminal device of a second type, which is not limited in this embodiment of the present invention.

It should be understood that table 1 is for illustrative purposes only and is not intended to limit embodiments of the present invention. For example, table 1 shows that the type indication field is immediately after the reserved field, but the type indication field may be located elsewhere in the random access response, and the type indication field occupies one or more bits. Optionally, the random access response may further include other fields, for example, a field for indicating an identity of the terminal device is further included, which is not limited in this embodiment of the present invention.

Table 1 example format of random access response

Retention

Type indication

Timing advance command

Alternatively, if the type of the first terminal device is indicated by the network device, the type of the first terminal device may remain substantially unchanged. For example, when the first terminal device regains uplink synchronization with the network device after uplink synchronization loss, or the first terminal device is restored from a sleep state to a connected state, the type of the first terminal device may remain unchanged, but the embodiment of the present invention does not exclude a case where the type of the first terminal device may change under certain specific conditions.

As another alternative embodiment, the method 200 further comprises: and if the first terminal equipment is out of synchronization in the uplink, acquiring the TA value of the first terminal equipment from the network equipment. Optionally, after the first terminal device acquires the TA value from the network device, the first terminal device may further continue to detect the first TA indication information. Specifically, the first terminal device may continue to detect the TA indication information sent by the second type terminal device, where the detection here may be blind detection, that is, the first terminal device performs detection without knowing the sender, and a TA value indicated by the first TA indication information detected by the first terminal device in the process of continuing the detection may be different from a TA value indicated by the first TA indication information detected in S220, which is not limited in this embodiment of the present invention.

Specifically, when the first terminal device is out of synchronization in the uplink, the first terminal device may perform signaling interaction with the network device to obtain uplink synchronization with the network device again, for example, obtain a TA value in a closed-loop manner. After uplink synchronization is obtained again, the first terminal device may still be a coarse TA device, continue to detect TA indication information sent by the second type terminal device, and adjust its TA value according to the detected TA indication information, but the embodiment of the present invention is not limited thereto.

As another alternative, the first terminal device may also determine its own type by determining whether there is a fine TA device around it. Accordingly, prior to S210, the method 200 includes:

detecting second TA indication information, which is sent by a third terminal device determined to be a second type of terminal device, when initially accessing the network device or switching from a sleep state to a connected state, and is used for indicating a TA value of the third terminal device;

and if the second TA indication information is detected within a preset time period, determining that the first terminal equipment is the first type of terminal equipment.

The first terminal device may determine a configuration for the terminal device of the second type to send the TA indication information, and detect the TA indication information sent by the terminal device of the second type according to the configuration, where the configuration may be predefined or preconfigured by the network device, which is not limited in this embodiment of the present invention. The third terminal device has been determined to be of a second type, wherein the third terminal device may be any terminal device different from the first terminal device, and the third terminal device may be the same or different terminal device as the second terminal device. Alternatively, the detection may be blind detection, that is, the first terminal device performs detection without knowing in advance which terminal device the third terminal device is, but the embodiment of the present invention is not limited thereto.

Specifically, the first terminal device may start a timer when it needs to determine its type, for example, initially access the network device or switch from a sleep state to a connection state, and start to detect TA indication information sent by the second type terminal device, where a duration of the timer (i.e., a length of the preset time period) may be predefined or indicated by the network device through signaling. If the first terminal device detects the TA indication information sent by the second type of terminal device before the timer expires, indicating that the first terminal device is located within the broadcast range of a certain precise TA device, the first terminal device may determine its TA value according to the TA value of the precise TA device without directly interacting with the network device, at this time, the first terminal device may determine that it is the first type of terminal device, that is, the first terminal device is the coarse TA device, and the first terminal device may continue to detect the TA indication information sent by the precise TA device. Optionally, if the first terminal device does not detect TA indication information sent by any fine TA device when the timer expires, it indicates that the first terminal device is not located within a broadcast range of any fine TA device, at this time, the first terminal device may determine that the first terminal device is a terminal device of the second type, that is, the first terminal device is a fine TA device, and the first terminal device may obtain a TA value of the first terminal device from the network device, but the embodiment of the present invention is not limited thereto.

The first terminal device may perform the above procedure to determine its type only after initially accessing the network device, and the type may remain unchanged after the determination; alternatively, the first terminal device may perform the above procedure periodically or triggered after accessing the network device to determine its own type. For example, if the first terminal device is restored to the connected state from the sleep state (not receiving the message), the first terminal device may perform the above procedure to determine its own type; or, if the first terminal device goes out of synchronization in the uplink, the above procedure may be performed to determine the type of itself, and so on, but the embodiment of the present invention is not limited thereto.

Optionally, if the first terminal device determines that it is a first type terminal device at a first time and needs to determine its type again at a second subsequent time, for example, when switching from a sleep state to a connected state or uplink is out of synchronization, the first terminal device may perform the above-mentioned process of detecting the second TA indication information again and determining whether the second TA indication information is detected within a second time period of a specific time duration; if the first terminal equipment detects second TA indicating information in a second time period, the first terminal equipment is still the first type terminal equipment; and if the first terminal device does not detect the second TA indication information within the second time period, the first terminal device is changed from the first type terminal device to the second type terminal device, at this time, the type of the first terminal device is variable, but the embodiment of the present invention does not limit this.

As another alternative embodiment, the method 200 further comprises: and if the first terminal equipment is out of synchronization in the uplink, acquiring the TA value of the first terminal equipment from the network equipment. Optionally, after obtaining the TA value from the network device, the first terminal device may still be the terminal device of the first type, or may determine that the first terminal device is changed from the terminal device of the first type to the terminal device of the second type, or the network device may redetermine the type of the first terminal device and notify the first terminal device, or the first terminal device may redetermine the detection process of the TA indication information to determine its type, which is not limited in the embodiment of the present invention.

In the embodiment of the present invention, the first terminal device may determine that the uplink is out of synchronization in a plurality of ways. Optionally, the first terminal device may determine that the uplink is out of synchronization by itself, for example, the first terminal device may reset a time alignment timer after acquiring an initial TA value or adjusting its own TA value, determine whether to acquire TA adjustment information before the time alignment timer expires, and determine that the first terminal device is out of synchronization in the uplink if the TA adjustment information is not acquired. Optionally, as another embodiment, the first terminal device may receive third indication information sent by the network device, where the third indication information is used to indicate that the first terminal device is out of synchronization in the uplink, and determine that the uplink is out of synchronization according to the third indication information. For example, the network device may measure uplink information (e.g., uplink data or a reference signal such as a demodulation reference signal) transmitted by the first terminal device to determine an uplink synchronization deviation between the first terminal device and the network device. If the uplink synchronization deviation exceeds the maximum allowable range, the network device determines that the first terminal device is out of synchronization in an uplink manner, and notifies the first terminal device in an explicit or implicit manner, but the embodiment of the present invention is not limited thereto.

In this embodiment of the present invention, a transmission resource of the first terminal device for detecting the second TA indication information and/or the first TA indication information may be predefined, or before detecting the second TA indication information and/or the first TA indication information, the first terminal device may further receive second indication information sent by the network device, where the second indication information is used to indicate the transmission resource of the second TA indication information and/or the first TA indication information, and accordingly, the first terminal device may detect the second TA indication information and/or the first TA indication information by using the transmission resource. The first terminal device may receive the second indication information during a random access procedure or after accessing the network device, and the second indication information and the first indication information may be sent in the same message or different messages, which is not limited in this embodiment of the present invention.

As an alternative embodiment, before S210, the method 200 further includes:

receiving second indication information sent by the network equipment, wherein the second indication information is used for indicating at least one of transmission resources, transmission power and transmission modes of the first TA indication information;

accordingly, S210, detecting the first TA indication information includes: and detecting the first TA indication information according to the second indication information.

Specifically, the first terminal device may detect the first TA indication information using a transmission resource indicated by the second indication information, where the transmission resource may include at least one of time, frequency, space, code, and pilot, and the first terminal device may further detect the first TA indication information according to at least one of a transmission power and a transmission manner indicated by the second indication information, but the embodiment of the present invention is not limited thereto. Optionally, the second indication information may be further used to indicate other configurations of the first TA indication information, which is not limited in this embodiment of the present invention. Optionally, the first TA indication information and the second TA indication information may have the same configuration, or the first TA indication information and the second TA indication information may have different configurations, and the second indication information may be further used to indicate the configuration of the second TA indication information, such as transmission resource, transmission power, length of transmission mode or timer (i.e. length of preset time period), and the like, but the embodiment of the present invention is not limited thereto.

In the embodiment of the present invention, the transmission power (hereinafter referred to as TA broadcast power) used when the fine TA device sends the TA indication information may be specified by a standard, or may be preconfigured by the network device. The TA broadcast power setting may take into account the following factors: on one hand, the TA broadcast power can be as large as possible to cover more coarse TA devices, thereby reducing the burden and overhead of the network device in maintaining TA as much as possible; on the other hand, the TA broadcast power needs to enable the coarse TA device located within the transmission distance of the TA indication information to use the same TA value for uplink synchronization, that is, the TA broadcast power needs to meet the requirement of the TA adjustment granularity. Specifically, taking TA precision in LTE standard as an example, the granularity of TA adjustment is 16T_sWherein T is_sThe sampling interval of the system indicates that the TA adjustment granularity of the LTE system is about 0.52 μ s, and the corresponding signal transmission distance is about 78 m. This means that in an LTE system, terminal devices within 78 meters of range can use the same TA value. Therefore, the fine TA device in the LTE system may control the TA broadcast power such that the transmission distance of the TA indication information is less than 78 meters. Similarly, the fine TA device in the GSM system may adjust the granularity according to the TA of the GSM system, and control the TA broadcast power, so that the transmission distance of the TA indication information sent by the fine TA device is within 550 meters. Optionally, in the embodiment of the present invention, other factors may also be considered when determining the TA broadcast power, which is not limited in the embodiment of the present invention.

As an alternative embodiment, the second indication Information may be carried in a System Information Block (SIB) 2. An exemplary structure of SIB2 is shown below, in which a sidelinkPowerControlCommon field is newly added in a radioresourceconfigcommon SIB field of SIB2, and power control information of the TA indication information is carried in the newly added sidelinkPowerControlCommon. Optionally, the SIB2 may also have other formats, and the power control information may also be carried in other fields of the SIB2, which is not limited in this embodiment of the present invention.

Wherein, the sildelinkpowercontrolcommon field may have the following format:

SidelinkPowerControlCommon::＝SEQUENCE{

p0-NominalPSBCH INTEGER(-126..24),

}

wherein, the field p0-NominalPSBCH INTEGER carries power control information, but the embodiment of the present invention is not limited thereto.

Fig. 5 shows a scenario of a terminal device located at a cell edge. As shown in fig. 5, terminals a and B are at the edges of cell a and cell B and reside in cell B. The terminal d residing in the cell a and the terminal e residing in the cell B are fine TA devices, and the remaining terminals are coarse TA devices. Terminal a is located at the edge of the broadcast range of terminal d and outside the broadcast range of terminal e, so terminal a can receive the TA indication information broadcast by terminal d, but cannot receive the TA indication information broadcast by terminal e. Terminal b is located in the overlapping area of the broadcast ranges of terminal d and terminal e, so terminal b can receive the TA indication information broadcast by terminal d as well as the TA indication information broadcast by terminal e. At this time, the terminals a and B may use the TA indication information sent by the fine TA device residing in the cell a to establish uplink synchronization with the network device B, thereby causing uplink synchronization failure.

In order to avoid the foregoing situation, optionally, when the terminal device initially accesses the cell B, the network device B may notify the terminal device of the transmission resource used by the fine TA device in the cell to send the TA indication information in the random access process. In addition, multiple cells may perform joint scheduling, so that the TA indication information in each cell occupies different transmission resources. In this way, the terminal device may detect the TA indication information using the transmission resource (e.g., time-frequency resource) corresponding to the camped cell. As another optional embodiment, the TA indication information broadcasted by the fine TA device may also be used to indicate a cell identifier corresponding to the TA value. At this time, after receiving TA indication information sent by a certain fine TA device, the coarse TA device may decode the received TA indication information to obtain a cell identifier indicated by the TA indication information, and determine whether a cell corresponding to the cell identifier is a current camped cell of the coarse TA device, if so, the coarse TA device may complete uplink synchronization with the network device using a TA value indicated by the TA indication information, otherwise, the coarse TA device may discard the TA indication information, but the embodiment of the present invention is not limited thereto.

Optionally, the first TA indication information is further used to indicate a serving cell of the second terminal device, that is, to indicate a cell corresponding to the TA value, and accordingly, S220 determines the TA value of the first terminal device according to the detected first TA indication information, including:

and if the current serving cell of the first terminal equipment is the same as the serving cell indicated by the first TA indication information, determining the TA value of the first terminal equipment according to the detected first TA indication information.

At this time, the first TA indication information may be used to indicate a TA value of the second terminal device and a cell corresponding to the TA value, for example, the first TA indication information includes an identifier of the cell corresponding to the TA value, and optionally, the first TA indication information may further include other information, but the embodiment of the present invention is not limited thereto.

The first terminal device may determine whether the cell indicated in the detected first TA indication information is a current serving cell of the first terminal device, and if so, the first terminal device may determine a TA value of itself according to the detected first TA indication information; if not, the first terminal device may discard the first TA indication information, but the embodiment of the present invention is not limited thereto. In this way, it is possible to avoid uplink synchronization failure caused by that the terminal a or B in fig. 5 performs uplink synchronization with the network device B by using the TA indication information sent by the terminal d.

Therefore, in the communication method provided in the embodiment of the present invention, the first terminal device detects the first TA indication information sent by the second terminal device, where the first TA indication information is used to indicate a TA value of the second terminal device, and the first terminal device determines the TA value of itself according to the detected first TA indication information, without directly interacting with the network device.

Fig. 6 illustrates a communication method 300 provided by another embodiment of the invention. The method 300 may be performed by a second terminal device.

S310, obtain the TA value of the second terminal device from the network device.

The second terminal device may obtain its TA value from the network device when determining that it is the second type terminal device. Optionally, the second terminal device may obtain the TA value from the network device in a closed-loop manner, but the embodiment of the present invention is not limited thereto.

S320, sending first TA indication information to the first terminal device, where the first TA indication information is used to indicate a TA value of the second terminal device.

The first terminal device is a first type terminal device, optionally, the second terminal device may send the first TA indication information to the first terminal device in a unicast manner, or may send the first TA indication information to at least one terminal device of the first type in a multicast manner, or may send the first TA indication information in a broadcast manner, which is not limited in this embodiment of the present invention.

Therefore, in the communication method provided in the embodiment of the present invention, the second terminal device obtains the TA value of itself from the network device, and sends the first TA indication information for indicating the TA value of itself to the first terminal device, so that the first terminal device can determine the TA value of itself according to the first TA indication information, without directly interacting with the network device.

Optionally, the first TA indication information is further used for indicating a serving cell of the second terminal device.

At this time, the first TA indication information may include information of a serving cell of the second terminal device, and is used to indicate a TA value at which the second terminal device maintains uplink synchronization with the serving cell, so that the first terminal device may perform uplink synchronization with the serving cell indicated by the first indication information according to the TA value indicated by the first indication information. Optionally, after receiving the first TA indication information, it may be determined whether the cell indicated by the first TA indication information is the same as the current serving cell of the first terminal device, and if so, determine the TA value of itself according to the TA value indicated by the first indication information, but the embodiment of the present invention is not limited thereto.

In the embodiment of the present invention, the second terminal device may determine its own type in various ways. Optionally, before S310, the method 300 further includes:

and receiving first indication information sent by the network equipment, wherein the first indication information is used for indicating that the second terminal equipment is the second type terminal equipment, and the second type terminal equipment acquires the TA value from the network equipment.

The second terminal device may determine, according to the first indication information, that the second terminal device is a second type of terminal device, optionally, the first indication information may be further used to indicate a TA value of the second terminal device, and accordingly, the second terminal device may determine the TA value of the second terminal device according to the first indication information. Optionally, the first indication information may explicitly or implicitly indicate that the second terminal device is a second type of terminal device, and in addition, the network device may send the first indication information to the second terminal device during or after the random access of the second terminal device. Optionally, the receiving the first indication information sent by the network device includes: and receiving the first indication information sent by the network equipment in the random access process.

For example, the second terminal device may receive a random access response sent by the network device, where the random access response carries the first indication information, but the embodiment of the present invention is not limited thereto.

As another alternative embodiment, before S310, the method 300 further includes:

detecting second TA indication information, which is sent by a third terminal device determined to be a second type of terminal device, when initially accessing the network device or switching from a sleep state to a connected state, and is used for indicating a TA value of the third terminal device;

and if the second TA indication information is not detected within the preset time period, determining that the second terminal equipment is the second type of terminal equipment.

The second terminal device may start a timer, and start to detect the TA indication information sent by the second type terminal device, where a duration of the timer (i.e., a length of the preset time period) may be predefined or indicated by the network device through signaling. If the second terminal device does not detect the TA indication information sent by the second type of terminal device when the timer is overtime, it indicates that there are no other fine TA devices around the second terminal device, and the second terminal device may determine that it is the second type of terminal device, that is, the second terminal device is the fine TA device. Alternatively, the second terminal device may perform blind detection, i.e. detection without prior knowledge of which terminal device the third terminal device is specifically. The configuration of the second TA indication information may be predefined or preconfigured by the network device. Optionally, before detecting the second TA indication information, the second terminal device may further receive second indication information sent by the network device, where the second indication information is used to indicate a configuration of the second type of terminal device to send the TA indication information, for example, at least one of a transmission resource, a transmission power, and a transmission manner, or may further include a duration of the timer, where the transmission resource may include at least one of a time resource, a frequency resource, a space resource, a code resource, and a pilot resource, and accordingly, the second terminal device may detect the second TA indication information using the configuration indicated by the second indication information, but the embodiment of the present invention is not limited thereto.

The second terminal device may perform the above procedure to determine its type only after initially accessing the network device, and the type may remain unchanged after the determination; alternatively, the second terminal device may perform the above procedure periodically or triggered after accessing the network device to determine its own type. For example, if the second terminal device is restored from the sleep state to the connection state, the second terminal device may execute the above procedure to determine its own type; or, if the second terminal device goes out of synchronization in the uplink, the above procedure may be performed to determine the type of itself, and so on, but the embodiment of the present invention is not limited thereto.

Optionally, if the second terminal device determines that it is a second type terminal device at a first time and needs to determine its type again at a second subsequent time, for example, when switching from a sleep state to a connected state or uplink is out of synchronization, the second terminal device may perform the above-mentioned process of detecting the second TA indication information again and determining whether the second TA indication information is detected within a second time period of a specific time duration; if the second terminal equipment does not detect the second TA indication information in the second time period, the second terminal equipment is still the second type terminal equipment; and if the second terminal device detects the second TA indication information within the second time period, the second terminal device is changed from the second type terminal device to the first type terminal device, at this time, the type of the second terminal device is variable, but the embodiment of the present invention does not limit this.

In this embodiment of the present invention, the second terminal device may send the first TA indication information in a variety of ways. Optionally, S320, sending the first TA indication information to the first terminal device, where the sending includes: the first TA indication information is transmitted on a D2D broadcast channel.

The second terminal device may transmit the first TA indication information in a D2D manner, for example, the second terminal device may transmit the first TA indication information on a PSBCH or other D2D broadcast channel, but the embodiment of the present invention is not limited thereto.

Furthermore, the second terminal device may periodically transmit the first TA indication information, where a transmission period may be predefined or preconfigured by the network device, or the second terminal device may trigger to transmit the first TA indication information, for example, the second terminal device may transmit the first TA indication information when its TA value is adjusted, but the embodiment of the present invention is not limited thereto.

The configuration of the second terminal device to send the first TA indication information may be predefined or indicated by the network device. As an alternative embodiment, before S320, the method 300 further includes:

receiving second indication information sent by the network equipment, wherein the second indication information is used for indicating at least one of transmission resources, transmission power and transmission modes of the first TA indication information;

correspondingly, S320, sending the first TA indication information to the first terminal device, including:

and sending the first TA indication information to the first terminal equipment according to the second indication information.

The second terminal device may send the first TA indication information to the first terminal device using at least one of a transmission resource, a transmission power, and a transmission manner indicated by the second indication information.

In this embodiment of the present invention, before sending the TA indication information, the fine TA device may perform the following processing procedures:

(1) scrambling

For the information bit sequence b (0) to be transmitted_b-1), wherein M_bIndicating the number of bits included in the TA indication information. The fine TA device may scramble it with the sequence c (i) resulting in a scrambled bit sequence where,

(2) modulation

The fine TA device modulates the bit sequence after scrambling to obtain a complex modulation symbol sequence d (0)_s-1) wherein M_sThe number of complex-valued symbols included for a sequence of complex-valued symbols. Alternatively, if the fine TA device sends the TA indication information on a Physical downlink Broadcast Channel (PSBCH), the TA indication information may be modulated by using a Quadrature Phase Shift Keying (QPSK) modulation method, but the embodiment of the present invention does not limit this.

(3) Layer mapping and precoding

For the modulation symbol sequence d (0) ·, d (M)_s-1) performing layer mapping to obtain a sequence of symbols x (i) ═ x⁽⁰⁾(i)...x^(v-1)(i)]^TWhere v denotes the number of layers, and i is 0,1, …, which is the number of adjustment symbols mapped per layer.

Specifically, if one antenna port is used to transmit TA indication information, v is 1, and the mapping criterion is specifically x⁽⁰⁾(i)＝d(i)。

If transmit diversity is used, v is equal to the number of antenna ports P of the terminal device used for transmitting the physical channel, the mapping criteria of which may be as shown in table 2.

Table 2 example of layer mapping of modulation symbols in transmit diversity mode

Subsequently, the symbol sequence x (i) ═ x may be mapped to⁽⁰⁾(i)...x^(v-1)(i)]^TPrecoding to obtain a vector y (i) [. y [.. y)^(p)(i)...]^T，

Specifically, if one antenna port is used for transmission, the vector y is output^(p)(i)＝x⁽⁰⁾(i) Where p is the antenna port number used for physical channel transmission.

If transmit diversity mode is employed, then two antenna ports are used: port 0 and 1, output vector y (i) ═ y⁽⁰⁾(i)y⁽¹⁾(i)]^TWherein the output vector may be obtained by:

when four antenna ports are used: port 0-3, output vector y (i) ═ y⁽⁰⁾(i)y⁽¹⁾(i)y⁽²⁾(i)y⁽³⁾(i)]^TAlternatively, other numbers of antenna ports or transmission modes may be used, and the embodiments of the invention are not limited thereto.

(4) Precoding output vector y (i) [. y [.. y)^(p)(i)...]^TMapping onto transmission resource blocks.

Therefore, in the communication method provided in the embodiment of the present invention, the second terminal device obtains the TA value of itself from the network device, and sends the first TA indication information for indicating the TA value of itself to the first terminal device, so that the first terminal device can determine the TA value of itself according to the first TA indication information, without directly interacting with the network device.

Fig. 7 illustrates a communication method 400 provided by another embodiment of the invention. The method 400 may be performed by a network device.

S410, determining transmission resources of TA indication information, wherein the TA indication information is sent to the first type terminal equipment by the second type terminal equipment, and the TA indication information sent by the second type terminal equipment is used for indicating the TA value of the second type terminal equipment.

In the embodiment of the present invention, the first type of terminal device corresponds to a coarse TA device, and the second type of terminal device corresponds to a fine TA device, where the fine TA device acquires its TA value from the network device and sends TA indication information for indicating its TA value. The coarse TA device may detect the TA indication information and determine the TA value thereof according to the TA value indicated by the detected TA indication information, for example, determine the TA value indicated by the detected TA indication information as the TA value thereof.

Optionally, the TA indication information may also be used to indicate a jurisdiction to which the second type of terminal device belongs, such as a cell identity (cell ID) of a serving cell, but the embodiment of the present invention is not limited thereto.

S420, sending second indication information, where the second indication information is used to indicate transmission resources of the TA indication information.

The network device may send the second indication information to some or all of the user equipments served, for example, the network device may send the second indication information to at least one terminal device, where the at least one terminal device may include at least one fine TA device and/or at least one coarse TA device. Furthermore, the network device may send the second indication information in a unicast manner, a multicast manner, or a broadcast manner, for example, the network device may broadcast the second indication information, but the embodiment of the present invention is not limited thereto.

Optionally, the transmission resource may be a transmission resource used for sending or receiving TA indication information for all terminal devices in the jurisdiction of the network device, that is, the terminal devices in the jurisdiction of the network device, whether being the first type terminal devices or the second type terminal devices, all use the same determined transmission resource to send or receive the TA indication information. Optionally, the second indication information may also be used to indicate a range governed by the network device, for example, the second indication information includes a Cell identity (Cell ID) of a Cell controlled by the network device, but the embodiment of the present invention is not limited thereto.

Therefore, in the communication method provided in the embodiment of the present invention, the network device sends the second indication information for indicating the transmission resource of the TA indication information, so that the second type of terminal device sends the TA indication information according to the transmission resource, the first type of terminal device monitors the TA indication information according to the transmission resource, and can determine its TA value according to the detected TA indication information, without directly interacting with the network device.

Optionally, the second indication information may further indicate at least one of a transmission power and a transmission mode of the TA indication information. The network device may determine the transmit power of the TA indication information in a variety of ways. As an alternative embodiment, before S420, the method 400 further includes:

determining the expected transmission distance of the TA indication information according to the TA adjustment granularity;

and determining the transmitting power of the TA indication information according to the expected transmission distance.

The expected transmission distance of the TA indication information corresponds to an expected coverage of the TA indication information, and the network device may determine the transmission power of the TA indication information according to the expected coverage, so that multiple terminal devices located within the coverage of the TA indication information may maintain uplink synchronization with the network device using the same TA value, but the embodiment of the present invention is not limited thereto.

As another alternative, the network device may also configure the type of the terminal device. Accordingly, the method 400 further comprises:

determining that the first terminal equipment is the first type of terminal equipment or the second type of terminal equipment;

and sending first indication information to the first terminal device, wherein the first indication information is used for indicating that the first terminal device is the terminal device of the first type or the terminal device of the second type.

The network device may determine that the first terminal device is the first type terminal device or the second type terminal device in various ways, for example, the network device may determine that the first terminal device is the first type terminal device or the second type terminal device according to one or more of the service type, the location information, the capability information, the subscription information, and the like of the first terminal device, for example, the network device may determine a fine TA device from a terminal device with a large data volume, frequent data transmission, and a stable power supply, and determine a coarse TA device from a terminal device with a small data volume, a low data transmission frequency, and a limited battery capability, but the embodiment of the present invention is not limited thereto. After determining the type of the first terminal device, the network device may send, to the first terminal device, first indication information used for indicating the type of the first terminal device, and optionally, the first indication information is also used for indicating an initial TA value of the first terminal device, but the embodiment of the present invention is not limited thereto.

The network device may send the first indication information in multiple ways, and optionally, the sending the first indication information to the first terminal device includes: and sending the first indication information to the first terminal equipment in the random access process of the first terminal equipment.

As another optional embodiment, the network device may further detect whether a certain terminal device maintains uplink synchronization, and notify the terminal device when the terminal device goes out of synchronization in uplink. Accordingly, the method 400 further comprises:

receiving uplink information sent by second terminal equipment;

determining the uplink desynchronizing of the second terminal equipment according to the received uplink information;

and sending third indication information to the second terminal equipment, wherein the third indication information is used for indicating the uplink desynchronization of the second terminal equipment.

The uplink information may include uplink data or a reference signal, such as a demodulation reference signal, but the embodiment of the present invention is not limited thereto. The network device may measure the uplink information to determine an uplink synchronization deviation between the second terminal device and the network device, and if the uplink synchronization deviation exceeds a threshold, the network device may determine that the second terminal device is out of synchronization in an uplink direction and notify the second terminal device through a signaling. Optionally, the third indication information may further be used to indicate a current TA value of the second terminal device, so that the second terminal device obtains uplink synchronization with the network device again according to the TA value indicated by the third indication information, but the embodiment of the present invention is not limited thereto.

Therefore, in the communication method provided in the embodiment of the present invention, the network device sends the second indication information for indicating the transmission resource of the TA indication information, so that the second type of terminal device sends the TA indication information according to the transmission resource, the first type of terminal device monitors the TA indication information according to the transmission resource, and can determine its TA value according to the detected TA indication information, without directly interacting with the network device.

Fig. 8 illustrates a communication method 500 provided by another embodiment of the invention. The method 500 may be performed by a network device.

S510, determining that the first terminal device is a first type terminal device or a second type terminal device, where the second type terminal device is a terminal device that obtains a TA value from a network device, and the first type terminal device is a terminal device that obtains a TA value from TA indication information sent by the detected second type terminal device.

The network device may determine that the type of the first terminal device is a first type or a second type and signal the first terminal device.

S520, sending first indication information, where the first indication information is used to indicate that a first terminal device is the terminal device of the first type or the terminal device of the second type.

Specifically, the network device may send the first indication information to the first terminal device.

Optionally, S520, the sending the first indication information includes: and sending the first indication information in the random access process of the first terminal equipment.

Therefore, in the communication method provided in the embodiment of the present invention, the terminal device is configured as the first type terminal device or the second type terminal device through the network device, wherein the second type terminal device obtains the TA value of itself from the network device, and sends the TA indication information for indicating the TA value of itself to the first type terminal device, so that the first type terminal device can determine the TA value of itself according to the detected TA indication information, and does not need to directly interact with the network device.

The communication method provided by the embodiment of the present invention will be described in more detail with reference to specific examples. Fig. 9 is a schematic flow chart diagram of another communication method 600 provided by an embodiment of the present invention.

S610, when the terminal device initially accesses the network, the first indication information sent by the network device is received in the random access process, and the terminal device is determined to be the first type of terminal device or the second type of terminal device according to the first indication information, namely the terminal device is determined to be the coarse TA device or the fine TA device.

The network device may send the first indication information in a unicast, multicast or broadcast manner, where a transmission resource used when the network device broadcasts the first indication information may be predefined, but the embodiment of the present invention does not limit this. In addition, the first indication information may further be used for control information including TA indication information, for example, one or more of transmission resources, transmission power, and transmission mode (modulation and coding mode, number of antenna ports, and the like), and optionally, the first indication information may also be used for indicating other configurations of the TA indication information, which is not limited in this embodiment of the present invention.

If the terminal device belongs to the fine TA device, the terminal device may complete initial uplink synchronization with the network device in the random access process, obtain an initial TA value of itself, and the terminal device may perform S620. If the terminal equipment belongs to the coarse TA equipment, the terminal equipment can select whether to obtain an initial TA value in the random access process. If the coarse TA device obtains its initial TA value in the random access process, the coarse TA device may perform data transmission using the initial TA value, and perform S630, where the coarse TA device may periodically or continuously monitor TA indication information, and adjust its TA value according to the monitored TA indication information, that is, update the initial TA value to the TA value indicated by the monitored TA indication information, but the embodiment of the present invention is not limited thereto. Optionally, if the coarse TA device does not obtain the initial TA value in the random access procedure, the coarse TA device may perform S630, and determine its initial TA value and update the TA value according to the monitored TA indication information, i.e., perform S630, but the embodiment of the present invention is not limited thereto.

S620, the terminal device broadcasts TA indication information indicating its own TA value.

S630, monitoring TA indication information, and obtaining self TA value from the monitored TA indication information.

And S640, the terminal equipment and the network equipment perform data transmission.

S650, the terminal equipment determines whether the uplink is out of step.

If the terminal device is in uplink synchronization, the terminal device may update its TA value, and maintain uplink synchronization with the network device using the updated TA value. The fine TA device may perform S670 and S630, that is, periodically or triggerably receive TA update information sent by the network device, update the TA value according to the TA update information to maintain uplink synchronization with the network device, and periodically or triggerably broadcast TA indication information indicating its current TA value. The coarse TA user may maintain uplink synchronization with the network device by performing S630.

If the terminal equipment is out of synchronization in the uplink, S660 is executed. Specifically, if the fine TA device is out of synchronization upstream, the fine TA device may stop broadcasting the TA indication information and interact with the network device again to regain upstream synchronization with the network device, and then may restart broadcasting the TA indication information. If the coarse TA device is out of synchronization in the uplink, the coarse TA device may also interact with the network device to regain uplink synchronization with the network device, and continue to monitor the TA indication information after regaining uplink synchronization.

And S660, acquiring the TA value from the network equipment in a closed-loop mode, and acquiring uplink synchronization with the network equipment again.

And S670, receiving TA update information sent by the network equipment, and updating the TA value according to the TA update information.

Therefore, in the communication method provided in the embodiment of the present invention, the terminal device is configured as the first type terminal device or the second type terminal device through the network device, wherein the second type terminal device obtains the TA value of itself from the network device, and sends the TA indication information for indicating the TA value of itself to the first type terminal device, so that the first type terminal device can determine the TA value of itself according to the detected TA indication information, and does not need to directly interact with the network device.

Fig. 10 is a schematic flow chart diagram of another communication method 700 provided by an embodiment of the present invention. Unlike the way in which the type of the terminal device is configured by the network device in the method 600, in the method 700 shown in fig. 10, the type of the terminal device may be determined by monitoring TA indication information broadcast by other terminal devices.

S710, when the terminal device needs to determine its own type, for example, initially access to the network or wake up from a sleep state, it may determine the configuration of the TA indication information.

Optionally, the terminal device may receive second indication information sent by the network device, where the second indication information is used to indicate configuration of the TA indication information, for example, at least one of transmission resource, transmission power, and transmission mode of the TA indication information, or further used to indicate the terminal device to detect a length of a timer of the TA indication information, which is not limited in this embodiment of the present invention.

S720, the terminal equipment starts a timer and detects and receives the TA indication information which may exist according to the configuration of the TA indication information.

The method for the terminal device to detect the TA indication information and the length of the timer may be predefined or obtained from the second indication information sent by the network device, which is not limited in the embodiment of the present invention.

S730, the terminal device determines whether TA indication information is detected when the timer expires.

If the terminal device detects the TA indication information, it may be determined that the terminal device is a coarse TA device, and optionally, the coarse TA device may further obtain a TA value from the detected TA indication information, complete uplink synchronization with the network device, and then start data transmission. Meanwhile, the coarse TA device may perform S750 to maintain uplink synchronization with the network device.

If the terminal device does not detect the TA indication information, it may be determined that the terminal device is a fine TA device, and S740 is performed, but the embodiment of the present invention is not limited thereto.

As another optional embodiment, if the terminal device correctly receives the TA indication information before the timer expires, it indicates that the terminal device is in the coverage area broadcasted by some or some fine TA devices, and the terminal device becomes a coarse TA device. If the terminal device does not correctly receive any TA indication information before the timer times out, it indicates that the terminal device is not in the broadcast range of other fine TA devices or in the overlapping area of the broadcast ranges of a plurality of fine TA devices, so that TA indication information broadcast from a plurality of fine TA devices interferes with each other, so that the terminal device cannot correctly decode TA indication information broadcast by any one fine TA device, and at this time, the terminal device can become a fine TA device.

S740, the fine TA device obtains its own TA value through interaction with the network device, and broadcasts TA indication information for indicating its own TA value by using predefined transmission resources or transmission resources indicated by the network device, and specific transmission power and transmission mode.

The fine TA device may determine whether the uplink is out of synchronization. If the fine TA device goes out of synchronization in the uplink in the process of data transmission, the TA indication information broadcasting can be stopped, and the closed-loop interaction process is performed again with the network device to obtain uplink synchronization with the network device again.

S750, the coarse TA device may detect TA indication information on a specific transmission resource, and update its TA value according to the detected first TA indication information, so as to maintain uplink synchronization with the network device.

S760, the coarse TA device determines whether to go up and go out of synchronization.

S750 may be continuously or periodically performed if the coarse TA device is uplink synchronized. If the coarse TA device is out of synchronization upstream, the coarse TA device may re-acquire upstream synchronization with the network device by performing closed-loop interaction with the network device, and the coarse TA device automatically transitions to a fine TA device.

Therefore, in this embodiment, the identity types of the terminal devices are not fixed, and each terminal device confirms the identity type of itself in the same manner and can convert the identity types. The embodiment is more suitable for networks with basically the same type of terminal equipment, and the probability of becoming the fine TA equipment or the coarse TA equipment is basically the same among the equipment, so the fairness is better.

It should be noted that the examples of fig. 9 and 10 are provided to assist those skilled in the art to better understand the embodiments of the present invention, and are not intended to limit the scope of the embodiments of the present invention. It will be apparent to those skilled in the art that various equivalent modifications or variations are possible in light of the examples given in fig. 9 and 10, and such modifications or variations are also within the scope of the embodiments of the invention.

It should be understood that the sequence numbers of the above-mentioned processes do not mean the execution sequence, and the execution sequence of each process should be determined by its function and inherent logic, and should not constitute any limitation to the implementation process of the embodiment of the present invention.

The communication method according to the embodiment of the present invention is described in detail above with reference to fig. 1 to 10, and the communication apparatus according to the embodiment of the present invention will be described below with reference to fig. 11 to 18.

Fig. 11 shows a communication apparatus 800 according to an embodiment of the present invention, where the apparatus 800 includes:

a detecting unit 810, configured to detect first TA indication information, where the first TA indication information is sent by a second terminal device, and the first TA indication information is used to indicate a TA value of the second terminal device;

a determining unit 820, configured to determine a TA value of the first terminal device according to the first TA indication information detected by the detecting unit 810.

Optionally, the first TA indication information is further used for indicating a serving cell of the second terminal device; correspondingly, the determining unit 820 is further configured to determine the TA value of the first terminal device according to the first TA indication information detected by the detecting unit 810 if the current serving cell of the first terminal device is the same as the serving cell indicated by the first TA indication information.

Optionally, the determining unit 820 is specifically configured to determine the TA value indicated by the first TA indication information detected by the detecting unit 810 as the TA value of the first terminal device.

The first terminal device may be a first type terminal device, and the second terminal device may be a second type terminal device, where the second terminal device may obtain its TA value from the network device.

As an alternative embodiment, the apparatus 800 further comprises: a first receiving unit, configured to receive first indication information sent by a network device before the detecting unit 810 detects the first TA indication information, where the first indication information is used to indicate that the first terminal device is a first type of terminal device, where the first type of terminal device is a terminal device that acquires a TA value from TA indication information sent by a second type of terminal device, and the second type of terminal device is a terminal device that acquires a TA value from the network device.

Optionally, the first receiving unit is specifically configured to receive the first indication information sent by the network device in a random access process. At this time, the first receiving unit may receive first indication information sent by the network device in a process that the first terminal device randomly accesses the network device.

Optionally, as another embodiment, the apparatus 800 further includes: a first obtaining unit, configured to obtain a TA value of the first terminal device from the network device if the first terminal device is out of synchronization in an uplink direction;

optionally, the detecting unit 810 is further configured to continue to detect the first TA indication information after the first obtaining unit obtains the TA value from the network device.

As another optional embodiment, the detecting unit 810 is further configured to detect second TA indication information when initially accessing the network device or switching from the sleep state to the connected state, where the second TA indication information is sent by a third terminal device that has been determined to be a second type of terminal device, and the second TA indication information is used to indicate a TA value of the third terminal device;

correspondingly, the determining unit 820 is further configured to determine that the first terminal device is a first type of terminal device if the detecting unit 810 detects the second TA indication information within a preset time period.

Optionally, as another embodiment, the apparatus 800 further includes: a second obtaining unit, configured to obtain, from the network device, the TA value of the first terminal device if the first terminal device is out of synchronization in the uplink.

Optionally, the determining unit 820 is further configured to determine that the first terminal device is changed from the terminal device of the first type to the terminal device of the second type when the first terminal device is out of synchronization in the uplink.

As another alternative embodiment, the detecting unit 810 is further configured to detect the second TA indication information again when switching from the sleep state to the connected state;

correspondingly, the determining unit 820 is further configured to determine that the first terminal device is changed from the first type terminal device to the second type terminal device if the detecting unit 810 does not detect the second TA indication information within the preset time period.

As another alternative embodiment, the detecting unit 810 is specifically configured to: the first TA indication information is detected on the D2D broadcast channel.

As another alternative embodiment, the apparatus 800 further comprises: a second receiving unit, configured to receive second indication information sent by the network device before the detecting unit 810 detects the first TA indication information, where the second indication information is used to indicate at least one of a transmission resource, a transmission power, and a transmission manner of the first TA indication information;

accordingly, the detecting unit 810 is specifically configured to detect the first TA indication information according to the second indication information received by the second receiving unit.

The communication apparatus 800 according to the embodiment of the present invention may correspond to the first terminal device in the communication method according to the embodiment of the present invention, and the above and other operations and/or functions of each module in the communication apparatus 800 are respectively for implementing corresponding flows of each method in fig. 3 to fig. 10, and are not described herein again for brevity.

Therefore, in the communication apparatus provided in the embodiment of the present invention, by detecting the first TA indication information sent by the second terminal device, where the first TA indication information is used to indicate a TA value of the second terminal device, and the first terminal device determines its TA value according to the detected first TA indication information, it is not necessary to directly interact with the network device.

Fig. 12 shows another communication apparatus 900 provided in an embodiment of the present invention, where the apparatus 900 includes:

an obtaining unit 910, configured to obtain a TA value of a second terminal device from a network device;

a sending unit 920, configured to send first TA indication information to the first terminal device, where the first TA indication information is used to indicate the TA value acquired by the acquiring unit 910.

The first terminal device may be a first type of terminal device, and the transmitting unit may transmit the first TA indication information in a unicast or broadcast form.

As another optional embodiment, the first TA indication information is further used for indicating a serving cell of the second terminal device.

As another alternative embodiment, the apparatus 900 further comprises: a first receiving unit, configured to receive first indication information sent by a network device before the obtaining unit 910 obtains a TA value of a second terminal device from the network device, where the first indication information is used to indicate that the second terminal device is a second type terminal device, and the second type terminal device is a terminal device that obtains the TA value from the network device.

At this time, the apparatus 900 may further include a determining unit, configured to determine that the second terminal device is a second type terminal device according to the first indication information received by the first receiving unit.

As an optional embodiment, the first receiving unit is specifically configured to receive the first indication information sent by the network device in a random access procedure. At this time, the first receiving unit is specifically configured to receive first indication information sent by the network device in a process that the second terminal device randomly accesses the network device, for example, the first indication information is carried in a random access response, but the embodiment of the present invention is not limited thereto.

As another alternative embodiment, the apparatus 900 further comprises:

a detecting unit, configured to detect second TA indication information when initially accessing the network device or switching from a sleep state to a connection state, where the second TA indication information is sent by a third terminal device that is determined to be the second type of terminal device, and the second TA indication information is used to indicate a TA value of the third terminal device;

and a determining unit, configured to determine that the second terminal device is a second type of terminal device if the detecting unit does not detect the second TA indication information within a preset time period.

As another optional embodiment, the detecting unit is further configured to detect the second TA indication information again when switching from the sleep state to the connected state;

correspondingly, the determining unit is further configured to determine that the second terminal device is changed from the second type terminal device to the first type terminal device if the detecting unit detects the second TA indication information within the preset time period.

As another alternative embodiment, the sending unit 920 is specifically configured to: the first TA indication information is transmitted on a D2D broadcast channel.

As another alternative embodiment, the apparatus 900 further comprises:

a second receiving unit, configured to receive second indication information sent by the network device before the sending unit 920 sends the first TA indication information to the first terminal device, where the second indication information is used to indicate at least one of a transmission resource, a transmission power, and a transmission mode of the first TA indication information;

accordingly, the sending unit 920 is specifically configured to send the first TA indication information to the first terminal device according to the second indication information received by the second receiving unit.

The communication apparatus 900 according to the embodiment of the present invention may correspond to the second terminal device in the communication method according to the embodiment of the present invention, and the above and other operations and/or functions of each module in the communication apparatus 900 are respectively for implementing corresponding flows of each method in fig. 3 to fig. 10, and are not described herein again for brevity.

Therefore, the communication apparatus provided in the embodiment of the present invention obtains the TA value of itself from the network device, and sends the first TA indication information for indicating the TA value of itself to the first terminal device, so that the first terminal device can determine the TA value of itself according to the first TA indication information, and does not need to directly interact with the network device.

Fig. 13 shows another communication apparatus 1100 according to an embodiment of the present invention, where the communication apparatus 1100 includes:

a determining unit 1110, configured to determine a transmission resource of TA indication information, where the TA indication information is sent by a second type of terminal device to a first type of terminal device, and the TA indication information is used to indicate a TA value of the second type of terminal device;

a sending unit 1120, configured to send second indication information, where the second indication information is used to indicate transmission resources of the TA indication information.

Specifically, the transmitting unit 1120 may transmit the second indication information to one or more terminal devices.

Optionally, the sending unit 1120 is specifically configured to send the second indication information in a broadcast form.

As another optional embodiment, the second indication information is further used for indicating the transmission power of the TA indication information;

accordingly, the determining unit 1110 is further configured to determine a desired transmission distance of the TA indication information according to the TA adjustment granularity, and determine a transmit power of the TA indication information according to the desired transmission distance, before the transmitting unit 1120 transmits the second indication information.

As another optional embodiment, the determining unit 1110 is further configured to determine that the first terminal device is the terminal device of the first type or the terminal device of the second type;

accordingly, the sending unit 1120 is further configured to send first indication information to the first terminal device, where the first indication information is used to indicate that the first terminal device determined by the determining unit 1110 is the terminal device of the first type or the terminal device of the second type.

At this time, the determining unit 1110 determines that the type of the first terminal device is the first type or the second type, and the transmitting unit 1120 transmits first indication information indicating the type of the first terminal device determined by the determining unit 1110 to the first terminal device.

As another optional embodiment, the sending unit 1120 is specifically configured to send the first indication information to the first terminal device in a random access procedure of the first terminal device.

As another alternative, the apparatus 1110 further comprises: a receiving unit, configured to receive uplink information sent by a second terminal device;

correspondingly, the determining unit 1110 is further configured to determine that the second terminal device is out of synchronization in the uplink direction according to the uplink information received by the receiving unit;

the sending unit 1120 is further configured to send third indication information to the second terminal device, where the third indication information is used to indicate that the second terminal device determined by the determining unit 1110 is out of synchronization in the uplink.

The communication apparatus 1100 according to the embodiment of the present invention may correspond to a network device in a communication method according to the embodiment of the present invention, and the above and other operations and/or functions of each module in the communication apparatus 1100 are respectively for implementing corresponding flows of each method in fig. 3 to fig. 10, and are not described herein again for brevity.

Therefore, in the communication apparatus provided in the embodiment of the present invention, by sending the second indication information for indicating the transmission resource of the TA indication information, the second type of terminal device sends the TA indication information according to the transmission resource, and the first type of terminal device monitors the TA indication information according to the transmission resource, and can determine its TA value according to the detected TA indication information, without directly interacting with the network device.

Fig. 14 shows a communication apparatus 1200 according to another embodiment of the present invention, where the apparatus 1200 includes:

a determining unit 1210, configured to determine that a first terminal device is a first type terminal device or a second type terminal device, where the second type terminal device is a terminal device that obtains a TA value from a network device, and the first type terminal device is a terminal device that obtains a TA value from TA indication information sent by the detected second type terminal device;

a sending unit 1220, configured to send first indication information, where the first indication information is used to indicate that the first terminal device determined by the determining unit 1210 is the terminal device of the first type or the terminal device of the second type.

Specifically, the determining unit 1210 may determine that the type of the first terminal device is a first type or a second type, and the sending unit sends the first indication information to the first terminal device, where the first indication information is used to indicate the type of the first terminal device determined by the determining unit 1210.

Optionally, the sending unit 1220 is specifically configured to send the first indication information in a random access procedure of the first terminal device. For example, the sending unit 1220 sends a random access response carrying the first indication information to the first terminal device, but the embodiment of the present invention is not limited thereto.

The communication apparatus 1200 according to the embodiment of the present invention may correspond to a network device in a communication method according to the embodiment of the present invention, and the above and other operations and/or functions of each module in the communication apparatus 1200 are respectively for implementing corresponding flows of each method in fig. 3 to fig. 10, and are not described herein again for brevity.

Therefore, the communication apparatus provided in the embodiment of the present invention configures a terminal device as a first type terminal device or a second type terminal device, where the second type terminal device obtains its TA value from a network device, and sends TA indication information for indicating its TA value to the first type terminal device, so that the first type terminal device can determine its TA value according to the detected TA indication information without directly interacting with the network device.

Fig. 15 shows a communication apparatus 1300 according to an embodiment of the present invention, where the apparatus 1300 includes: a processor 1310 configured to:

detecting first TA indication information, wherein the first TA indication information is sent by a second terminal device and is used for indicating a TA value of the second terminal device;

and determining the TA value of the first terminal equipment according to the detected first TA indication information.

The first terminal device may be a first type terminal device, and the second terminal device may be a second type terminal device, where the second terminal device may obtain its TA value from the network device.

As an optional embodiment, the first TA indication information is further used for indicating a serving cell of the second terminal device; correspondingly, the processor 1310 is further configured to determine a TA value of the first terminal device according to the detected first TA indication information if the current serving cell of the first terminal device is the same as the serving cell indicated by the first TA indication information.

Optionally, the processor 1310 is specifically configured to determine the TA value indicated by the detected first TA indication information as the TA value of the first terminal device.

As an alternative embodiment, as shown in fig. 15, the apparatus 1300 further comprises: a receiver 1320, configured to receive, before the processor 1310 detects the first TA indication information, first indication information sent by a network device, where the first indication information is used to indicate that the first terminal device is a first type of terminal device, where the first type of terminal device is a terminal device that obtains a TA value from TA indication information sent by a second type of terminal device, and the second type of terminal device is a terminal device that obtains a TA value from the network device.

At this time, the processor 1310 may be further configured to determine that the first terminal device is the first type of terminal device according to the first indication information received by the receiver 1320.

Optionally, the receiver 1320 is specifically configured to receive the first indication information sent by the network device in a random access procedure. At this time, the receiver 1320 may receive first indication information sent by the network device in a process that the first terminal device randomly accesses the network device.

Optionally, as another embodiment, the processor 1310 is further configured to: and if the first terminal equipment is out of synchronization in the uplink, acquiring the TA value of the first terminal equipment from the network equipment.

Optionally, the processor 1310 is further configured to continue to detect the first TA indication information after acquiring the TA value of the first terminal device from the network device.

As another alternative embodiment, the processor 1310 is further configured to:

detecting second TA indication information, which is transmitted by a third terminal device determined to be a second type of terminal device and is used for indicating a TA value of the third terminal device, when initially accessing the network device or switching from a sleep state to a connected state;

and if the second TA indication information is detected within a preset time period, determining that the first terminal equipment is the first type of terminal equipment.

Optionally, as another embodiment, the processor 1310 is further configured to: and if the first terminal equipment is out of synchronization in the uplink, acquiring the TA value of the first terminal equipment from the network equipment. Optionally, the processor 1310 is further configured to determine that the first terminal device is changed from the first type of terminal device to the second type of terminal device after obtaining the TA value from the network device.

As another alternative embodiment, the processor 1310 is specifically configured to: the first TA indication information is detected on the D2D broadcast channel.

As another alternative embodiment, the apparatus 1300 further comprises: a receiver 1320, configured to receive second indication information sent by a network device before the processor 1310 detects the first TA indication information, where the second indication information is used to indicate at least one of a transmission resource, a transmission power, and a transmission mode of the first TA indication information;

accordingly, the processor 1310 is specifically configured to detect the first TA indication information according to the second indication information received by the receiver 1320.

The communication apparatus 1300 according to the embodiment of the present invention may correspond to the first terminal device in the communication method according to the embodiment of the present invention, and the above and other operations and/or functions of each module in the communication apparatus 1300 are respectively for implementing corresponding flows of each method in fig. 3 to fig. 10, and are not described herein again for brevity.

Therefore, in the communication apparatus provided in the embodiment of the present invention, by detecting the first TA indication information sent by the second terminal device, where the first TA indication information is used to indicate a TA value of the second terminal device, and the first terminal device determines its TA value according to the detected first TA indication information, it is not necessary to directly interact with the network device.

Fig. 16 shows another communication apparatus 1400 provided in an embodiment of the present invention, where the apparatus 1400 includes:

a processor 1410, configured to obtain a TA value of the second terminal device from the network device;

a transmitter 1420, configured to transmit first TA indication information to the first terminal device, where the first TA indication information is used to indicate the TA value obtained by the processor 1410.

The first terminal device may be a first type of terminal device, and the transmitting unit may transmit the first TA indication information in a unicast or broadcast form.

As another optional embodiment, the first TA indication information is further used for indicating a serving cell of the second terminal device.

As another alternative embodiment, the apparatus 1400 further comprises: a receiver, configured to receive first indication information sent by the network device before the processor 1410 acquires the TA value of the second terminal device from the network device, where the first indication information is used to indicate that the second terminal device is a second type terminal device, and the second type terminal device is a terminal device that acquires the TA value from the network device.

At this time, the processor 1410 may be further configured to determine that the second terminal device is a second type of terminal device according to the first indication information received by the receiver.

As an optional embodiment, the receiver is specifically configured to receive the first indication information sent by the network device in a random access procedure. At this time, the receiver is specifically configured to receive first indication information sent by the network device in a process that the second terminal device randomly accesses the network device, for example, the first indication information is carried in a random access response, but the embodiment of the present invention is not limited thereto.

As another alternative embodiment, the processor 1410 is further configured to:

detecting second TA indication information, which is sent by a third terminal device determined to be the second type of terminal device, when initially accessing the network device or switching from a sleep state to a connected state, and is used for indicating a TA value of the third terminal device;

and if the second TA indication information is not detected within the preset time period, determining that the second terminal equipment is the second type of terminal equipment.

As another alternative embodiment, the transmitter 1420 is specifically configured to transmit the first TA indication information on the D2D broadcast channel.

As another alternative embodiment, the apparatus 1400 further comprises:

a receiver, configured to receive second indication information sent by a network device before the transmitter 1420 sends the first TA indication information to the first terminal device, where the second indication information is used to indicate at least one of a transmission resource, a transmission power, and a transmission manner of the first TA indication information;

accordingly, the transmitter 1420 is specifically configured to transmit the first TA indication information to the first terminal device according to the second indication information received by the receiver.

The communication apparatus 1400 according to the embodiment of the present invention may correspond to the second terminal device in the communication method according to the embodiment of the present invention, and the above and other operations and/or functions of each module in the communication apparatus 1400 are respectively for implementing corresponding flows of each method in fig. 3 to fig. 10, and are not described herein again for brevity.

Therefore, the communication apparatus provided in the embodiment of the present invention obtains the TA value of itself from the network device, and sends the first TA indication information for indicating the TA value of itself to the first terminal device, so that the first terminal device can determine the TA value of itself according to the first TA indication information, and does not need to directly interact with the network device.

Fig. 17 shows another communication apparatus 1500 provided in the embodiment of the present invention, where the communication apparatus 1500 includes:

a processor 1510, configured to determine a transmission resource of TA indication information, where the TA indication information is sent by a terminal device of a second type to a terminal device of a first type, and the TA indication information is used for indicating a TA value of the terminal device of the second type;

a transmitter 1520, configured to transmit second indication information indicating transmission resources of the TA indication information.

Specifically, the transmitter 1520 may transmit the second indication information to one or more terminal devices.

Optionally, the transmitter 1520 is specifically configured to transmit the second indication information in a broadcast form.

As another optional embodiment, the second indication information is further used for indicating the transmission power of the TA indication information;

accordingly, the processor 1510 is further configured to determine a desired transmission distance of the TA indication information according to the TA adjustment granularity and determine a transmission power of the TA indication information according to the desired transmission distance before the transmitter 1520 transmits the second indication information.

As another alternative embodiment, the processor 1510 is further configured to determine that the first terminal device is the terminal device of the first type or the terminal device of the second type;

accordingly, the transmitter 1520 is further configured to transmit first indication information to the first terminal device, where the first indication information indicates that the first terminal device determined by the processor 1510 is the first type of terminal device or the second type of terminal device.

At this time, the processor 1510 determines the type of the first terminal device as the first type or the second type, and the transmitter 1520 transmits first indication information indicating the type of the first terminal device determined by the processor 1510 to the first terminal device.

As another alternative, the transmitter 1520 is specifically configured to transmit the first indication information to the first terminal device in a random access procedure of the first terminal device.

As another alternative, the apparatus 1110 further comprises: the receiver is used for receiving uplink information sent by the second terminal equipment;

correspondingly, the processor 1510 is further configured to determine that the second terminal device is out of synchronization uplink according to the uplink information received by the receiver;

the transmitter 1520 is further configured to transmit third indication information to the second terminal device, where the third indication information is used to indicate that the second terminal device determined by the processor 1510 is out of synchronization in the uplink.

The communication apparatus 1500 according to the embodiment of the present invention may correspond to a network device in a communication method according to the embodiment of the present invention, and the above and other operations and/or functions of each module in the communication apparatus 1500 are respectively for implementing corresponding flows of each method in fig. 3 to fig. 10, and are not described herein again for brevity.

Therefore, in the communication apparatus provided in the embodiment of the present invention, by sending the second indication information for indicating the transmission resource of the TA indication information, the second type of terminal device sends the TA indication information according to the transmission resource, and the first type of terminal device monitors the TA indication information according to the transmission resource, and can determine its TA value according to the detected TA indication information, without directly interacting with the network device.

Fig. 18 shows a communication apparatus 1600 provided by another embodiment of the present invention, the apparatus 1600 includes:

a processor 1610, configured to determine that a first terminal device is a first type terminal device or a second type terminal device, where the second type terminal device is a terminal device that obtains a TA value from a network device, and the first type terminal device is a terminal device that obtains a TA value from TA indication information sent by the detected second type terminal device;

a transmitter 1620, configured to transmit first indication information, where the first indication information indicates that the first terminal device determined by the processor 1610 is the terminal device of the first type or the terminal device of the second type.

Specifically, the processor 1610 can determine that the type of the first terminal device is the first type or the second type, and the transmitter 1620 transmits the first indication information to the first terminal device, wherein the first indication information is used for indicating the type of the first terminal device determined by the processor 1610.

Optionally, the transmitter 1620 is specifically configured to transmit the first indication information in a random access procedure of the first terminal device. For example, the transmitter 1620 transmits a random access response carrying the first indication information to the first terminal device, but the embodiment of the present invention is not limited thereto.

The communication apparatus 1600 according to the embodiment of the present invention may correspond to a network device in a communication method according to the embodiment of the present invention, and the above and other operations and/or functions of each module in the communication apparatus 1600 are respectively for implementing corresponding flows of each method in fig. 3 to fig. 10, and are not described herein again for brevity.

Therefore, the communication apparatus provided in the embodiment of the present invention configures a terminal device as a first type terminal device or a second type terminal device, where the second type terminal device obtains its TA value from a network device, and sends TA indication information for indicating its TA value to the first type terminal device, so that the first type terminal device can determine its TA value according to the detected TA indication information without directly interacting with the network device.

It should be understood that, in the embodiment of the present invention, the processor in the above apparatus may be a Central Processing Unit (CPU), and the processor 610 may also be other general processors, Digital Signal Processors (DSPs), Application Specific Integrated Circuits (ASICs), ready-made programmable gate arrays (FPGAs) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, and the like. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.

Optionally, the apparatus may further comprise a memory, which may comprise read only memory and random access memory, and which provides instructions and data to the processor. The portion of memory may also include non-volatile random access memory. For example, the memory may also store device type information.

In implementation, the steps of the above method may be performed by integrated logic circuits of hardware in a processor or instructions in the form of software. The steps of a method disclosed in connection with the embodiments of the present invention may be directly implemented by a hardware processor, or may be implemented by a combination of hardware and software modules in the processor. The software module may be located in ram, flash memory, rom, prom, or eprom, registers, etc. storage media as is well known in the art. The storage medium is located in a memory, and a processor reads instructions in the memory and combines hardware thereof to complete the steps of the method. To avoid repetition, it is not described in detail here.

It should also be understood that the description herein of the various embodiments described above focuses on the differences between the various embodiments and the rest of the description may be mutually referenced. Technical features and descriptions in one embodiment above may be understood to be applicable to other embodiments, for example, technical features of a method embodiment may be applicable to an apparatus embodiment or other method embodiments, and are not described in detail in other embodiments.

It should also be understood that the transmitting unit or transmitter in the above embodiments may refer to transmitting over an air interface, and may transmit over an air interface instead of transmitting to other devices so that the other devices may transmit over the air interface. The receiving unit or the receiver in the above embodiments may refer to receiving over an air interface, and may receive over an air interface instead of receiving over an air interface, from another device receiving over an air interface.

It should be understood that in the embodiment of the present invention, the term and/or is only one kind of association relation describing the associated object, which means that there may be three kinds of relations. For example, a and/or B, may represent: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character/generally means that the pre-association object and the post-association object are in one or the same relationship.

Those of ordinary skill in the art will appreciate that the various method steps and elements described in connection with the embodiments disclosed herein can be implemented as electronic hardware, computer software, or combinations of both, and that the steps and elements of the various embodiments have been described above generally in terms of their functionality in order to clearly illustrate the interchangeability of hardware and software. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.

It is clear to those skilled in the art that, for convenience and brevity of description, the specific working processes of the above-described systems, apparatuses and units may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.

In the several embodiments provided in the present application, it should be understood that the disclosed system, apparatus and method may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the units is only one logical division, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may also be an electric, mechanical or other form of connection.

The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment of the present invention.

In addition, functional units in the embodiments of the present invention may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit.

The integrated unit, if implemented in the form of a software functional unit and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present invention essentially or partially contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product stored in a storage medium and including instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present invention. And the aforementioned storage medium includes: various media capable of storing program codes, such as a usb disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk, or an optical disk.

For brevity and clarity of the application, technical features and descriptions in one embodiment may be applied to other embodiments, for example, technical features of a method embodiment may be applied to an apparatus embodiment or other method embodiments, and are not described in detail in other embodiments.

The sending module, sending unit, or transmitter in the above embodiments may refer to sending over an air interface, and may send to other devices so that the other devices can send over the air interface instead of sending over the air interface. The receiving module, the receiving unit, or the receiver in the above embodiments may refer to receiving over an air interface, and may receive over an air interface instead of receiving over an air interface, from another device receiving over an air interface.

While the invention has been described with reference to specific embodiments, the invention is not limited thereto, and various equivalent modifications and substitutions can be easily made by those skilled in the art within the technical scope of the invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims (54)

1. A method of communication, comprising:

   the method comprises the steps that a first terminal device detects first Time Advance (TA) indication information, wherein the first TA indication information is sent by a second terminal device and is used for indicating a TA value of the second terminal device;

   and the first terminal equipment determines the TA value of the first terminal equipment according to the detected first TA indication information.
2. The method of claim 1, wherein the first TA indication information is further used for indicating a serving cell of the second terminal device;

   the determining the TA value of the first terminal device according to the detected first TA indication information includes:

   and if the current serving cell of the first terminal equipment is the same as the serving cell indicated by the first TA indication information, determining the TA value of the first terminal equipment according to the detected first TA indication information.
3. The method according to claim 1 or 2, wherein the determining the TA value of the first terminal device according to the detected first TA indication information comprises:

   and determining the TA value indicated by the detected first TA indication information as the TA value of the first terminal equipment.
4. The method according to any of claims 1-3, wherein prior to said detecting the first TA indication information, the method further comprises:

   receiving first indication information sent by a network device, where the first indication information is used to indicate that the first terminal device is a first type of terminal device, where the first type of terminal device is a terminal device that obtains a TA value from TA indication information sent by a second type of terminal device, and the second type of terminal device is a terminal device that obtains a TA value from the network device.
5. The method of claim 4, wherein the receiving the first indication information sent by the network device comprises:

   and receiving the first indication information sent by the network equipment in a random access process.
6. The method according to claim 4 or 5, characterized in that the method further comprises:

   if the first terminal equipment is out of synchronization in an uplink mode, a TA value of the first terminal equipment is obtained from the network equipment;

   and continuously detecting the first TA indication information.
7. The method according to any of claims 1-3, wherein prior to said detecting the first TA indication information, the method further comprises:

   the first terminal device detects second TA indication information when initially accessing the network device or switching from a sleep state to a connection state, wherein the second TA indication information is sent by a third terminal device which is determined to be a second type of terminal device, and the second TA indication information is used for indicating a TA value of the third terminal device;

   and if the second TA indication information is detected within a preset time period, determining that the first terminal equipment is the first type of terminal equipment.
8. The method of claim 7, further comprising:

   and if the first terminal equipment is out of synchronization in an uplink mode, the TA value of the first terminal equipment is obtained from the network equipment.
9. The method according to any of claims 1-8, wherein said detecting the first TA indication information comprises:

   the first TA indication information is detected on a device-to-device D2D broadcast channel.
10. The method according to any of claims 1-9, wherein prior to said detecting the first TA indication information, the method further comprises:

    receiving second indication information sent by a network device, wherein the second indication information is used for indicating at least one of transmission resources, transmission power and transmission modes of the first TA indication information;

    the detecting the first TA indication information includes:

    and detecting the first TA indication information according to the second indication information.
11. A method of communication, comprising:

    the second terminal equipment acquires a time advance TA value of the second terminal equipment from network equipment;

    the second terminal device sends first TA indication information to the first terminal device, wherein the first TA indication information is used for indicating a TA value of the second terminal device.
12. The method of claim 11, wherein the first TA indication information is further used for indicating a serving cell of the second terminal device.
13. The method according to claim 11 or 12, wherein prior to said obtaining the TA value of the second terminal device from the network device, the method further comprises:

    receiving first indication information sent by a network device, where the first indication information is used to indicate that the second terminal device is a second type of terminal device, and the second type of terminal device is a terminal device that obtains a TA value from the network device.
14. The method of claim 13, wherein the receiving the first indication information sent by the network device comprises:

    and receiving the first indication information sent by the network equipment in a random access process.
15. The method according to claim 11 or 12, wherein prior to said obtaining the TA value of the second terminal device from the network device, the method further comprises:

    detecting second TA indication information when initially accessing the network equipment or switching from a sleep state to a connection state, wherein the second TA indication information is sent by a third terminal equipment which is determined to be a second type of terminal equipment, and the second TA indication information is used for indicating a TA value of the third terminal equipment;

    and if the second TA indication information is not detected within a preset time period, determining that the second terminal equipment is the second type of terminal equipment.
16. The method according to any of claims 11 to 15, wherein said sending the first TA indication information to the first terminal device comprises:

    transmitting the first TA indication information on a device-to-device D2D broadcast channel.
17. The method according to any of claims 11-16, wherein prior to said sending the first TA indication information to the first terminal device, the method further comprises:

    receiving second indication information sent by a network device, wherein the second indication information is used for indicating at least one of transmission resources, transmission power and transmission modes of the first TA indication information;

    the sending the first TA indication information to the first terminal device includes:

    and sending first TA indication information to the first terminal equipment according to the second indication information.
18. A method of communication, comprising:

    determining transmission resources of TA indication information, wherein the TA indication information is sent to a first type of terminal equipment by a second type of terminal equipment, and the TA indication information sent by the second type of terminal equipment is used for indicating a TA value of the second type of terminal equipment;

    and sending second indication information, wherein the second indication information is used for indicating the transmission resource of the TA indication information.
19. The method of claim 18, wherein sending the second indication information comprises: and transmitting the second indication information in a broadcast form.
20. The method according to claim 18 or 19, wherein said second indication information is further used for indicating a transmission power of said TA indication information;

    before the sending the second indication information, the method further comprises:

    determining an expected transmission distance of the TA indication information according to TA adjustment granularity;

    and determining the transmitting power of the TA indication information according to the expected transmission distance.
21. The method of any one of claims 18 to 20, further comprising:

    determining that a first terminal device is the terminal device of the first type or the terminal device of the second type;

    and sending first indication information to the first terminal device, wherein the first indication information is used for indicating that the first terminal device is the terminal device of the first type or the terminal device of the second type.
22. The method of claim 21, wherein the sending the first indication information to the first terminal device comprises:

    and sending the first indication information to the first terminal equipment in the random access process of the first terminal equipment.
23. The method of any one of claims 18 to 22, further comprising:

    receiving uplink information sent by second terminal equipment;

    determining the uplink desynchronizing of the second terminal equipment according to the received uplink information;

    and sending third indication information to the second terminal equipment, wherein the third indication information is used for indicating the uplink desynchronization of the second terminal equipment.
24. A method of communication, comprising:

    determining that a first terminal device is a first type terminal device or a second type terminal device, wherein the second type terminal device is a terminal device which acquires a Time Advance (TA) value from a network device, and the first type terminal device is a terminal device which acquires the TA value from detected TA indication information sent by the second type terminal device;

    and sending first indication information, wherein the first indication information is used for indicating that the first terminal equipment is the terminal equipment of the first type or the terminal equipment of the second type.
25. The method of claim 24, wherein the sending the first indication information comprises:

    and sending the first indication information in the random access process of the first terminal equipment.
26. A communications apparatus, comprising:

    a detecting unit, configured to detect first Timing Advance (TA) indication information, where the first TA indication information is sent by a second terminal device and indicates a TA value of the second terminal device;

    and the determining unit is used for determining the TA value of the first terminal equipment according to the first TA indicating information detected by the detecting unit.
27. The apparatus of claim 26, wherein the first TA indication information is further used for indicating a serving cell of the second terminal device;

    the determining unit is specifically configured to determine the TA value of the first terminal device according to the first TA indication information detected by the detecting unit, if the current serving cell of the first terminal device is the same as the serving cell indicated by the first TA indication information.
28. The apparatus according to claim 26 or 27, wherein the determining unit is specifically configured to determine a TA value indicated by the first TA indication information detected by the detecting unit as the TA value of the first terminal device.
29. The apparatus of any one of claims 26 to 28, further comprising:

    a first receiving unit, configured to receive first indication information sent by a network device before the detecting unit detects the first TA indication information, where the first indication information is used to indicate that the first terminal device is a first type of terminal device, the first type of terminal device is a terminal device that obtains a TA value from TA indication information sent by a second type of terminal device, and the second type of terminal device is a terminal device that obtains a TA value from the network device.
30. The apparatus of claim 29, wherein the first receiving unit is specifically configured to receive the first indication information sent by the network device in a random access procedure.
31. The apparatus of claim 29 or 30, further comprising:

    a first obtaining unit, configured to obtain a TA value of the first terminal device from the network device if the first terminal device is out of synchronization in an uplink direction;

    the detecting unit is further configured to continue to detect the first TA indication information after the first obtaining unit obtains the TA value of the first terminal device from the network device.
32. The apparatus according to any of claims 26 to 28, wherein the detecting unit is further configured to detect second TA indication information when initially accessing a network device or switching from a sleep state to a connected state, where the second TA indication information is sent by a third terminal device that has been determined to be a second type of terminal device, and the second TA indication information is used to indicate a TA value of the third terminal device;

    the determining unit is further configured to determine that the first terminal device is a first type of terminal device if the detecting unit detects the second TA indication information within a preset time period.
33. The apparatus of claim 32, further comprising:

    a second obtaining unit, configured to obtain, from the network device, a TA value of the first terminal device if the first terminal device is out of synchronization in an uplink direction.
34. The device according to any one of claims 26 to 33, wherein the detection unit is specifically configured to:

    the first TA indication information is detected on a device-to-device D2D broadcast channel.
35. The apparatus of any one of claims 26 to 34, further comprising:

    a second receiving unit, configured to receive second indication information sent by a network device before the detecting unit detects the first TA indication information, where the second indication information is used to indicate at least one of a transmission resource, a transmission power, and a transmission manner of the first TA indication information;

    the detecting unit is specifically configured to detect the first TA indication information according to the second indication information received by the second receiving unit.
36. The apparatus according to any of claims 26 to 35, wherein the apparatus is the first terminal device.
37. A communications apparatus, comprising:

    an obtaining unit, configured to obtain a time advance TA value of a second terminal device from a network device;

    a sending unit, configured to send first TA indication information to a first terminal device, where the first TA indication information is used to indicate the TA value acquired by the acquiring unit.
38. The apparatus of claim 37, wherein the first TA indication information is further used for indicating a serving cell of the second terminal device.
39. The apparatus of claim 37 or 38, further comprising:

    a first receiving unit, configured to receive first indication information sent by a network device before the obtaining unit obtains a TA value of a second terminal device from the network device, where the first indication information is used to indicate that the second terminal device is a second type of terminal device, and the second type of terminal device is a terminal device that obtains the TA value from the network device.
40. The apparatus of claim 39, wherein the first receiving unit is specifically configured to receive the first indication information sent by the network device in a random access procedure.
41. The apparatus of claim 37 or 38, further comprising:

    a detecting unit, configured to detect second TA indication information when initially accessing the network device or switching from a sleep state to a connection state, where the second TA indication information is sent by a third terminal device that is determined to be the second type of terminal device, and the second TA indication information is used to indicate a TA value of the third terminal device;

    and the determining unit is configured to determine that the second terminal device is a second type of terminal device if the detecting unit does not detect the second TA indication information within a preset time period.
42. The apparatus according to any of claims 37 to 41, wherein the transmitting unit is specifically configured to transmit the first TA indication information on a device-to-device D2D broadcast channel.
43. The apparatus of any one of claims 37 to 42, further comprising:

    a second receiving unit, configured to receive second indication information sent by the network device before the sending unit sends the first TA indication information to the first terminal device, where the second indication information is used to indicate at least one of a transmission resource, a transmission power, and a transmission mode of the first TA indication information;

    the sending unit is specifically configured to send the first TA indication information to the first terminal device according to the second indication information received by the second receiving unit.
44. The apparatus according to any of claims 37 to 43, wherein the apparatus is the second terminal device.
45. A communications apparatus, comprising:

    a determining unit, configured to determine a transmission resource of Timing Advance (TA) indication information, where the TA indication information is sent by a second type of terminal device to a first type of terminal device, and the TA indication information is used for indicating a TA value of the second type of terminal device;

    a sending unit, configured to send second indication information, where the second indication information is used to indicate a transmission resource of the TA indication information.
46. The apparatus according to claim 45, wherein the sending unit is specifically configured to send the second indication information in a broadcast form.
47. The apparatus according to claim 45 or 46, wherein the second indication information is further used for indicating the transmission power of the TA indication information;

    the determining unit is further configured to determine an expected transmission distance of the TA indication information according to a TA adjustment granularity before the sending unit sends the second indication information, and determine a transmit power of the TA indication information according to the expected transmission distance.
48. The apparatus according to any of claims 45 to 47, wherein the determining unit is further configured to determine that a first terminal device is the terminal device of the first type or the terminal device of the second type;

    the sending unit is further configured to send first indication information to the first terminal device, where the first indication information is used to indicate that the first terminal device determined by the determining unit is the first type of terminal device or the second type of terminal device.
49. The apparatus of claim 48, wherein the sending unit is specifically configured to send the first indication information to the first terminal device in a random access procedure of the first terminal device.
50. The apparatus of any one of claims 45 to 49, further comprising:

    a receiving unit, configured to receive uplink information sent by a second terminal device;

    the determining unit is further configured to determine that the second terminal device is out of synchronization in an uplink manner according to the uplink information received by the receiving unit;

    the sending unit is further configured to send third indication information to the second terminal device, where the third indication information is used to indicate the uplink out-of-step of the second terminal device determined by the determining unit.
51. The apparatus according to any one of claims 45 to 50, wherein the apparatus is the network device.
52. A communications apparatus, comprising:

    a determining unit, configured to determine that a first terminal device is a first type terminal device or a second type terminal device, where the second type terminal device is a terminal device that obtains a TA value in advance from a network device, and the first type terminal device is a terminal device that obtains a TA value from TA indication information sent by the detected second type terminal device;

    a sending unit, configured to send first indication information, where the first indication information is used to indicate that the first terminal device determined by the determining unit is the terminal device of the first type or the terminal device of the second type.
53. The apparatus of claim 52, wherein the sending unit is specifically configured to send the first indication information in a random access procedure of the first terminal device.
54. The apparatus of claim 52 or 53, wherein the apparatus is the network device.