CN108886812B

CN108886812B - Method for sending random access leader sequence, terminal equipment and access network equipment

Info

Publication number: CN108886812B
Application number: CN201680084048.2A
Authority: CN
Inventors: 吴作敏; 马莎; 官磊
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2016-03-31
Filing date: 2016-03-31
Publication date: 2021-05-18
Anticipated expiration: 2036-03-31
Also published as: WO2017166253A1; CN108886812A

Abstract

The embodiment of the invention discloses a method for sending a random access leader sequence, which comprises the following steps: the method comprises the steps that a terminal device determines a first random access preamble sequence and determines a first PRACH resource from a first physical random access channel PRACH resource group, wherein the first PRACH resource comprises at least one basic resource unit, the basic resource unit can bear all information of the random access preamble sequence transmitted to an access network device by the terminal device in a random access process, and n is more than or equal to 1; the terminal equipment transmits a first random access preamble sequence on a first PRACH resource; when the random access process using the first random access preamble sequence fails, the terminal equipment determines a second random access preamble sequence and determines a second PRACH resource from a second PRACH resource group, wherein the number of basic resource units included in the second PRACH resource is greater than or equal to the number of basic resource units included in the first PRACH resource; and the terminal equipment transmits a second random access preamble sequence on a second PRACH resource.

Description

Method for sending random access leader sequence, terminal equipment and access network equipment

Technical Field

The present invention relates to the field of communications, and in particular, to a method, a terminal device, and an access network device for transmitting a random access preamble sequence.

Background

In the field of wireless communication, spectrum resources are mainly divided into licensed spectrum resources and unlicensed spectrum resources, and in an existing Long Term Evolution (LTE) system and an LTE Evolution system thereof, spectrum resources used by an operator are mainly licensed spectrum resources. With the increase of the number of mobile communication network terminal devices and the improvement of the requirements of users on communication rate and service quality, the existing licensed spectrum resources have difficulty in meeting the requirements of the existing services of operators. In consideration of high price and resource shortage of a new licensed spectrum, operators are looking at unlicensed spectrum resources, and it is expected that the purposes of network capacity offloading and service quality improvement can be achieved by utilizing the unlicensed spectrum resources.

In the existing LTE system, when the ue randomly accesses the base station, the power ramp method is used for transmitting the random access preamble sequence (which may also be referred to as a random access preamble). That is, when accessing the base station for the first time, the terminal device determines the initial power, the power offset, the power increasing factor and the maximum transmission number N for transmitting the random access preamble sequence. When the random access preamble sequence is transmitted for the first time, the power used by the terminal equipment is initial power + power offset, if the random access for the first time fails, the power used by the terminal equipment is initial power + power offset + power increment factor when the random access for the second time, and if the random access for the first time fails, the random access for the previous (N-1) times fails, and the power used by the terminal equipment is initial power + power offset + (N-1) times the power increment factor when the random access for the Nth time. It can be seen that, in the process of randomly accessing the base station by the terminal device, if the access is not successful all the time, the transmission power used by the terminal device when sending the random access preamble is gradually increased.

However, in order to avoid interference to other systems, many countries or regions have limitations on the maximum transmit power that can be used by devices using unlicensed spectrum resources. Therefore, when the random access preamble sequence is transmitted on the unlicensed spectrum resource, if the existing power ramp transmission mode is continuously used, the transmission power used by the user equipment in the process of initiating the random access may be limited due to the regulatory limitation.

Disclosure of Invention

The application provides a method for sending a random access preamble sequence, a terminal device and an access network device, which can improve the demodulation performance of the random access preamble sequence under the condition that the maximum transmission power is limited when the terminal device sends the random access preamble sequence on an unlicensed spectrum resource.

In a first aspect, the present application provides a method for transmitting a random access preamble sequence, the method comprising: the method comprises the steps that a terminal device determines a first random access preamble sequence and determines a first PRACH resource from a first physical random access channel PRACH resource group, wherein the first PRACH resource group comprises at least one PRACH resource used for performing nth random access, the first PRACH resource comprises at least one basic resource unit, and the basic resource unit can bear all information of the random access preamble sequence transmitted to an access network device by the terminal device in one random access process, wherein n is more than or equal to 1; the terminal equipment transmits the first random access preamble sequence on the first PRACH resource; when the random access process using the first random access preamble sequence fails, the terminal device determines a second random access preamble sequence and determines a second PRACH resource from a second PRACH resource group, where the second PRACH resource group includes at least one PRACH resource for performing random access for an (n + 1) th time, the second PRACH resource includes at least one basic resource unit, and the number of the basic resource units included in the second PRACH resource is greater than or equal to the number of the basic resource units included in the first PRACH resource; the terminal device transmits the second random access preamble sequence on the second PRACH resource.

In the existing LTE system, a power ramp mode is adopted for sending a Random Access Preamble sequence (Preamble) in a process of granting a Physical Random Access Channel (PRACH) on a spectrum resource, and before a terminal device successfully accesses the spectrum resource, power is increased when the Random Access Preamble sequence is sent next time every time the terminal device fails. With the development of communication networks, licensed spectrum resources are increasingly in short supply, more and more operators aim at unlicensed spectrum resources, and the purpose of network capacity distribution is expected to be achieved through the unlicensed spectrum resources. According to the regulation, the communication device applying the unlicensed spectrum resource can use the unlicensed spectrum resource for free only by meeting the requirements such as the transmission power, the power spectral density and the like. Therefore, if the random access preamble sequence is continuously transmitted on the unlicensed spectrum resource using the power ramp-up manner in the prior art, the maximum transmission power of the terminal device may be limited due to the limit of the transmission power by the regulations.

According to the method for sending the random access preamble sequence, when the terminal equipment sends the random access preamble sequence on the license-free frequency spectrum resource, under the condition that the maximum transmitting power is limited, the demodulation performance of the random access preamble sequence can be improved by increasing the time domain resource or the frequency domain resource used for transmitting the random access preamble sequence in the retransmission process.

Optionally, in a first possible implementation manner of the first aspect, the determining, by the terminal device, a first random access preamble sequence includes: the terminal equipment determines a first random access preamble sequence from a first random access preamble sequence group, wherein the first random access preamble sequence group comprises at least one random access preamble sequence used for performing nth random access; and the terminal device determines a second random access preamble sequence, including: the terminal device determines a second random access preamble sequence from a second random access preamble sequence group, wherein the second random access preamble sequence group includes at least one random access preamble sequence for performing n +1 th random access, and the first random access preamble sequence group is different from the random access preamble sequence included in the second random access preamble sequence group.

Optionally, in a second possible implementation manner of the first aspect, the method further includes:

the terminal equipment determines a random access wireless network temporary identifier corresponding to the second PRACH resource according to the time domain or frequency domain position of the basic resource unit included in the second PRACH resource;

and the terminal equipment receives a random access response sent by the access network equipment according to the random access wireless network temporary identifier.

In a second aspect, the present application provides a method of transmitting a random access preamble sequence, the method comprising:

an access network device receives a second random access preamble sequence sent by a first terminal device on a second PRACH resource, wherein the second random access preamble sequence is sent to the access network device after the first random access preamble sequence sent by the first terminal device to the access network device fails on a first PRACH resource, the first PRACH resource is determined by the first terminal device from a first PRACH resource group, the first PRACH resource group comprises at least one PRACH resource used for performing nth random access, the first PRACH resource comprises at least one basic resource unit, the second PRACH resource is determined by the first terminal device from a second PRACH resource group, the second PRACH resource group comprises at least one PRACH resource used for performing n +1 th random access, and the second PRACH resource comprises at least one basic resource unit, the number of the basic resource units included in the second PRACH resource is greater than or equal to the number of the basic resource units included in the first PRACH resource.

Optionally, in a first possible implementation manner of the second aspect, when the access network device receives, on the first PRACH resource, the first random access preamble sequence sent by the first terminal, the method further includes: the access network device receives a third random access preamble sequence transmitted by a second terminal device on a third PRACH resource, where the third PRACH resource is a PRACH resource determined by the second terminal device from the second PRACH resource group and used for performing random access for an (n + 1) th time, and the third PRACH resource satisfies at least one of the following conditions: the resources occupied by the third PRACH resource in the time domain at least include the resources occupied by the first PRACH resource in the time domain; the resources occupied by the third PRACH resource in the frequency domain at least include the resources occupied by the first PRACH resource in the frequency domain.

Optionally, in a second possible implementation manner of the second aspect, the method further includes: the access network equipment is configured with a plurality of random access preamble sequence groups, random access preamble sequences in any two random access preamble sequence groups are different, the random access preamble sequence groups are in one-to-one correspondence with a plurality of sequence detection formats, each sequence detection format is used for detecting a random access preamble sequence in the corresponding random access preamble sequence group, a first random access preamble sequence group in the random access preamble sequence groups comprises at least one sequence for performing nth random access, and a second random access preamble sequence group in the random access preamble sequence groups comprises at least one sequence for performing n +1 th random access.

In the embodiment of the present invention, the access network device may divide the available random access preamble sequences into a plurality of groups, and preset a detection format for each group. Therefore, when the base station detects the random access leader sequence, the random access leader sequences belonging to the same group use the same detection format, and the detection efficiency of the access network equipment can be improved.

Optionally, in a third possible implementation manner of the second aspect, the method further includes: when the access network equipment detects the second random access preamble sequence on the second PRACH resource, the access network equipment determines a random access wireless network temporary identifier corresponding to the second PRACH resource according to the time domain or frequency domain position of a basic resource unit included in the second PRACH resource;

the access network device sends a random access response to the first terminal device.

Optionally, in some implementations, the number of basic resource units included in the second PRACH resource is greater than the number of basic resource units included in the first PRACH resource, including at least one of: the number of the basic resource units included in the second PRACH resource in the time domain is greater than the number of the basic resource units included in the first PRACH resource in the time domain; the number of the basic resource units included in the frequency domain of the second PRACH resource is greater than the number of the basic resource units included in the frequency domain of the first PRACH resource.

Optionally, in some implementations, the number of basic resource units included in the second PRACH resource is equal to the number of basic resource units included in the first PRACH resource, at least one basic resource unit included in the first PRACH resource is located in P frequency domain unit groups, and at least one basic resource unit included in the second PRACH resource is located in Q frequency domain unit groups, where each frequency domain unit group includes R consecutive resource blocks RB, P is greater than or equal to 1, Q is greater than P, and R is greater than or equal to 1.

Optionally, in certain implementations, at least one of the following conditions is satisfied between the first PRACH resource and the second PRACH resource: the first PRACH resource is non-overlapping with the second PRACH resource in a time domain; the first PRACH resource and the second PRACH resource do not overlap in a frequency domain.

Optionally, in certain implementations, at least one of the following conditions is satisfied between the first PRACH resource group and the second PRACH resource group: the first PRACH resource group and the second PRACH resource group are not overlapped on a time domain; the first set of PRACH resources is non-overlapping with the second set of PRACH resources in a frequency domain.

Optionally, in some implementations, the basic resource unit includes N RBs in the frequency domain, N ≧ 2, the positional relationship of the N RBs including at least one of: the N RBs are contiguous in the frequency domain; at least two RBs of the N RBs are discontinuous; the frequency domain spacing between any two adjacent RBs of the N RBs is equal.

Optionally, in certain implementations, the distribution form of the first PRACH resource and the second PRACH resource on the frequency domain includes at least one of: the frequency domain interval between the first RB and the last RB occupied by the first PRACH resource on the frequency domain is greater than or equal to a preset frequency domain interval; the frequency domain interval between the first RB and the last RB occupied by the second PRACH resource in the frequency domain is greater than or equal to a preset frequency domain interval.

Optionally, in some implementations, the method further includes: the transmitting power used by the terminal equipment for transmitting the second random access preamble sequence on the second PRACH resource is greater than the transmitting power used by the terminal equipment for transmitting the first random access preamble sequence on the first PRACH resource.

Optionally, in some implementations, the second random access preamble sequence is the same as the first random access preamble sequence.

In a third aspect, the present application provides a terminal device, configured to execute the method in the first aspect or any possible implementation manner of the first aspect. In particular, the terminal device comprises means for performing the method of the first aspect or any possible implementation manner of the first aspect.

In a fourth aspect, the present application provides an access network device configured to perform the method of the second aspect or any possible implementation manner of the second aspect. In particular, the access network device comprises means for performing the method of the second aspect or any possible implementation of the second aspect.

In a fifth aspect, the present application provides a terminal device, including: a processor, a transceiver, and a memory. Optionally, the device further comprises a bus system, wherein the transceiver, the memory and the processor are connected by the bus system, the memory is configured to store instructions, the processor is configured to execute the instructions stored by the memory to control the transceiver to receive or transmit signals, and when the processor executes the instructions stored by the memory, the processor is configured to execute the method of the first aspect or any possible implementation manner of the first aspect.

In a sixth aspect, the present application provides an access network device, including: a processor, a transceiver, and a memory. Optionally, the device further comprises a bus system, wherein the receiver, the transceiver, the memory and the processor are connected by the bus system, the memory is used for storing instructions, the processor is used for executing the instructions stored by the memory to control the transceiver to receive or transmit signals, and when the processor executes the instructions stored by the memory, the method in any possible implementation manner of the second aspect is executed by the processor.

In a seventh aspect, a computer-readable medium is provided for storing a computer program comprising instructions for performing the method of the first aspect or any possible implementation manner of the first aspect.

In an eighth aspect, there is provided a computer readable medium for storing a computer program comprising instructions for performing the method of the second aspect or any possible implementation of the second aspect.

Drawings

Fig. 1 is an application scenario of a method for transmitting a random access preamble sequence according to an embodiment of the present invention.

Fig. 2 shows a schematic interaction diagram of a method of transmitting a random access preamble sequence according to an embodiment of the present invention.

Fig. 3 shows a schematic diagram of PRACH resources used by a UE in a random access procedure.

Fig. 4 shows another schematic diagram of PRACH resources used by a UE in a random access procedure.

Fig. 5 shows another schematic diagram of PRACH resources used by a UE in a random access procedure.

Fig. 6 shows yet another schematic diagram of PRACH resources used by a UE.

Fig. 7 shows yet another schematic diagram of PRACH resources used by a UE.

Fig. 8 shows a schematic diagram of PRACH resources used by multiple UEs.

Fig. 9 shows a schematic diagram of a distribution manner of PRACH resources used by a UE on a system bandwidth in a random access procedure.

Fig. 10 shows a schematic block diagram of a terminal device according to an embodiment of the present invention.

Fig. 11 shows a schematic block diagram of an access network device according to another embodiment of the invention.

Fig. 12 shows a schematic block diagram of a terminal device according to an embodiment of the present invention.

Fig. 13 shows a schematic structural block diagram of an access network device according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be described below with reference to the drawings in the embodiments of the present invention.

The technical solution of the embodiment of the present invention can be applied to various communication systems of a wireless cellular network, 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) System, an LTE System, a Universal Mobile Telecommunications System (UMTS), a future 5G communication System, and the like, which are not limited in this embodiment of the present invention.

The technical scheme of the embodiment of the invention is mainly applied to a Long Term Evolution (LTE) system and an Evolution system thereof, in particular to a Licensed-Assisted Access Using LTE (LAA-LTE) system. In the communication system applied in the embodiment of the present invention, the network elements involved are an access network device (also referred to as a network device) and a terminal device (also referred to as a user equipment).

The present invention describes various embodiments in conjunction with a Terminal device, which may be referred to as a User Equipment (UE), a Mobile Station (MS), a Mobile Terminal (Mobile Terminal), etc., and the Terminal device may communicate with one or more core networks through a Radio Access Network (RAN). For example, the terminal equipment may be a mobile phone (or so-called "cellular" phone), a computer with a mobile terminal, etc., and the terminal equipment may also be a portable, pocket, hand-held, computer-included or vehicle-mounted mobile device and terminal equipment in future 5G networks, which exchange voice or data with the radio access network.

In addition, various embodiments are described herein in connection with an access network device. The Access network device may be an evolved Node B (evolved Node B, which may be referred to as eNB or e-NodeB for short) macro base station, a micro base station (also referred to as a "small base station"), a pico base station, an Access Point (AP), or a Transmission Point (TP), etc. in a Long Term Evolution (LTE) system or an LAA-LTE system.

Fig. 1 illustrates an application scenario of a method for transmitting a random access preamble sequence, which is applicable to an embodiment of the present invention. As shown in fig. 1, the scenario includes a cell base station 101, a cell base station 102 adjacent to the cell base station 101, and a user equipment 103. Wherein the user equipment 103 is in a coverage area smaller than the base station 101 and communicates with the cell base station 101. Cell base station 101 and user equipment 103 are communication devices that support communication over unlicensed spectrum resources. The frequency bands supported by the cell base station 102 may be the same as the cell base station 101, and the cell base station 102 may be a communication device of the same type as the cell base station 101 or a communication device of a different type from the cell base station 101. For example, the cell base station 101 may be a base station of an LTE system, correspondingly, the user equipment 103 may be a user equipment of the LTE system, and the cell base station 102 may be a base station of the LTE system, and may also be a Wireless router, a Wireless relay, or a user equipment of a Wireless Fidelity (Wi-Fi) system. In a specific communication process, when the user equipment 103 transmits a signal to the cell base station 102 through a channel of the unlicensed spectrum, the user equipment 103 needs to acquire a channel usage right of the unlicensed spectrum and comply with a restriction requirement of resource usage on the unlicensed spectrum on transmission power and bandwidth.

Hereinafter, a method for transmitting a random access preamble sequence according to an embodiment of the present invention will be described in detail with reference to fig. 2 to 9.

Fig. 2 shows a schematic interaction diagram 100 of a method of transmitting a random access preamble sequence according to an embodiment of the present invention.

Optionally, step 101 may be included in an embodiment of the present invention.

101. The base station configures a plurality of physical random access channel PRACH resource groups, wherein a first PRACH resource group in the plurality of PRACH resource groups comprises at least one PRACH resource for performing nth random access, a second PRACH resource group in the plurality of PRACH resource groups comprises at least one PRACH resource for performing n +1 th random access, each PRACH resource in the first PRACH resource group and the second PRACH resource group comprises at least one basic resource unit, the basic resource units can bear all information of a random access preamble sequence transmitted to access network equipment by terminal equipment in one random access process, the number of the basic resource units comprised by the second PRACH resource is greater than or equal to the number of the basic resource units comprised by the first PRACH resource, and n is greater than or equal to 1.

It should be noted that, in the embodiment of the present invention, the basic resource unit refers to a minimum time-frequency resource unit capable of bearing all information of the random access preamble sequence transmitted by the terminal device to the access network device in a random access process. One basic resource unit may include 1 RB or may include a plurality of RBs. Alternatively, one basic resource unit includes 6 RBs. Alternatively, one basic resource unit includes 1 RB.

Typically, PRACH resources include time domain resources, frequency domain resources, and sequence resources. In the embodiments of the present invention, the time domain resource and the frequency domain resource of the PRACH resource are mainly referred to.

It should be understood that the above multiple Physical Random Access Channel (PRACH) resource groups are only a logical group concept, that is, in practice, a base station may configure only one PRACH resource group, which includes multiple PRACH resources for Random Access. Thus, it can be understood that the plurality of PRACH resource groups correspond to a plurality of random access procedures one to one, and each PRACH resource group corresponds to a certain random access. In other words, when initiating the random access process to the access network device, the terminal device selects the PRACH resource group to be used in the current random access according to the number of times of the random access failure, and selects one PRACH resource from the selected PRACH resource group for random access.

It should be noted that the terminal device may select the PRACH resource specified by the access network device based on the scheduling of the access network device (e.g., the base station) (or, in other words, based on non-contention). The terminal device may also randomly select one PRACH resource from the corresponding set of PRACH resources by itself (i.e., contention-based). That is, the embodiment of the present invention is not particularly limited to the method for selecting the PRACH resource by the terminal device.

For example, the PRACH resources in the PRACH resource set #1 are used for the 2 nd random access, the PRACH resources in the PRACH resource set #2 are used for the 4 th random access, and so on. Assuming that the 1 st random access of the UE #1 (i.e., an example of the UE) fails, when initiating the 2 nd random access procedure, the UE #1 may determine one PRACH resource from a plurality of PRACH resources in the PRACH resource set #1 for the 2 nd random access. If the previous 3 times of random access of the UE #1 fail, when the UE #1 initiates the 4 th time of random access to the base station, one PRACH resource may be determined from the PRACH resource group #2 for the 4 th time of random access.

It should also be understood that the above numbers "first" and "second" are only used for distinguishing different objects, for example, for distinguishing different PRACH resources or different random access preamble sequences, and should not constitute any limitation to the random access procedure according to the embodiments of the present invention.

Optionally, as an embodiment, the method further includes:

the access network equipment configures a plurality of random access preamble sequence groups, the random access preamble sequence groups correspond to a plurality of sequence detection formats one to one, each sequence detection format is used for detecting a random access preamble sequence in the corresponding random access preamble sequence group, a first random access preamble sequence group in the random access preamble sequence groups comprises at least one sequence used for performing nth random access, a second random access preamble sequence group in the random access preamble sequence groups comprises at least one sequence used for performing n +1 th random access, and the first random access preamble sequence group is different from the random access preamble sequence in the second random access preamble sequence group.

It should be noted that, the sequence detection format corresponds to the number or position of the time domain resource and the frequency domain resource occupied by the random access preamble sequence. If the two random access preamble sequences occupy different amounts of time domain resources or different amounts of frequency domain resources, it can be considered that the two random access preamble sequences correspond to different sequence detection formats.

In the embodiment of the present invention, the base station may divide the available random access preamble sequences into a plurality of groups, where the random access preamble sequence used for the mth transmission and the random access preamble sequence used for the nth transmission belong to different groups. Meanwhile, a plurality of random access preamble sequence groups correspond to a plurality of sequence detection formats one to one. Thus, when the base station detects the sequence at the receiving side, the base station only needs to detect the random access leader sequence in the group corresponding to the format according to different formats. The detection efficiency of the base station can be improved.

102. The method comprises the steps that a terminal device determines a first random access preamble sequence and determines a first PRACH resource from a first physical random access channel PRACH resource group, wherein the first PRACH resource group comprises at least one PRACH resource used for performing nth random access, the first PRACH resource comprises at least one basic resource unit, the basic resource unit can bear all information of the random access preamble sequence transmitted to an access network device by the terminal device in one random access process, and n is larger than or equal to 1.

Specifically, the terminal device may have various ways when determining the first random access preamble sequence. For example, the base station sends an indication signaling to the UE, where the indication signaling carries an identification ID of a first random access preamble sequence, and the UE determines the first random access preamble sequence from an available random access preamble sequence set according to the identification ID of the first random access preamble sequence. For another example, the base station signals the UE to send the random access preamble sequence without notifying the ID of the random access preamble sequence, and the UE randomly selects one from the available random access preamble sequence set as the determined random access preamble sequence (i.e., may correspond to the first random access preamble sequence). For another example, the UE may also autonomously determine a random access preamble sequence (i.e., may correspond to the first random access preamble sequence) from a set of available random access preamble sequences at random.

Similarly, there may be several ways for the UE to determine the first PRACH resource. For example, the system may pre-define PRACH resources that the UE can use when making the nth random access. When the UE initiates the nth random access procedure to the base station, it determines a PRACH resource (for convenience of description, it is referred to as PRACH resource #1) from PRACH resources predefined by the system and used for the nth random access, and initiates the nth random access procedure to the base station on the PRACH resource # 1. For another example, the PRACH resource used when the UE initiates the nth random access procedure to the base station is signaled to the UE by the base station. And the UE initiates the nth random access process to the base station by using the PRACH resource for the nth random access indicated by the signaling of the base station, wherein n is more than or equal to 1.

Optionally, as an embodiment, the basic resource unit includes N RBs in the frequency domain, where N ≧ 2, the positional relationship of the N RBs includes at least one of:

the N RBs are contiguous in the frequency domain;

at least two RBs of the N RBs are discontinuous;

the frequency domain spacing between any two adjacent RBs of the N RBs is equal.

103. The terminal equipment transmits a first random access preamble sequence on the first PRACH resource.

104. When the random access process using the first random access preamble sequence fails, the terminal device determines a second random access preamble sequence, and determines a second PRACH resource from a second PRACH resource group, where the second PRACH resource group includes at least one PRACH resource for performing n +1 th random access, the second PRACH resource includes at least one basic resource unit, and the number of the basic resource units included in the second PRACH resource is greater than or equal to the number of the basic resource units included in the first PRACH resource.

It should be understood that, when the nth random access procedure fails, the UE needs to initiate an (n + 1) th random access procedure to the base station. Similar to the nth random access process, before performing the (n + 1) th random access, the UE needs to determine a random access preamble sequence (i.e., may correspond to the second random access preamble sequence) for performing the (n + 1) th random access and a PRACH resource (i.e., may correspond to the second PRACH resource) for carrying the random access preamble sequence. The process of determining the second random access preamble sequence for performing the (n + 1) th random access is similar to the process of determining the first random access preamble sequence for the nth random access and determining to carry the first random access preamble sequence, and the process of determining the second PRACH resource is similar to the process of determining the first PRACH resource, and is not repeated here for brevity.

In the embodiment of the present invention, both the first PRACH resource and the second PRACH resource include at least one basic resource unit, where the number of the basic resource units included in the second PRACH resource is greater than or equal to the number of the basic resource units included in the first PRACH resource.

Optionally, as an embodiment, the number of basic resource units included in the second PRACH resource is greater than the number of basic resource units included in the first PRACH resource, and includes at least one of the following cases:

the number of the basic resource units included in the second PRACH resource in the time domain is larger than that of the basic resource units included in the first PRACH resource in the time domain;

the number of the basic resource units included in the frequency domain of the second PRACH resource is greater than the number of the basic resource units included in the frequency domain of the first PRACH resource.

It should be noted that, if the number of the basic resource units included in the time domain of the first PRACH resource is greater than the number of the basic resource units included in the time domain of the second PRACH resource, in the frequency domain, the following possibilities are included between the number of the basic resource units included in the first PRACH resource and the number of the basic resource units included in the frequency domain of the second PRACH resource:

(1) the number of the basic resource units included in the frequency domain of the first PRACH resource is equal to the number of the basic resource units included in the frequency domain of the second PRACH resource.

(2) The number of the basic resource units included in the frequency domain of the first PRACH resource is greater than the number of the basic resource units included in the frequency domain of the second PRACH resource.

(3) The number of the basic resource units included in the frequency domain of the first PRACH resource is less than the number of the basic resource units included in the frequency domain of the second PRACH resource, and the sum of the numbers of the basic resource units included in the time domain and the frequency domain of the first PRACH resource is greater than the sum of the numbers of the basic resource units included in the time domain and the frequency domain of the second PRACH resource.

If the number of the basic resource units included in the frequency domain of the first PRACH resource is greater than the number of the basic resource units included in the frequency domain of the second PRACH resource, in the time domain, the following possibilities are included between the number of the basic resource units included in the first PRACH resource and the number of the basic resource units included in the time domain of the second PRACH resource:

(1) the number of the basic resource units included in the time domain of the first PRACH resource is equal to the number of the basic resource units included in the time domain of the second PRACH resource.

(2) The number of the basic resource units included in the time domain of the first PRACH resource is greater than the number of the basic resource units included in the time domain of the second PRACH resource.

(3) The number of the basic resource units included in the time domain of the first PRACH resource is less than the number of the basic resource units included in the time domain of the second PRACH resource, and the sum of the numbers of the basic resource units included in the time domain and the frequency domain of the first PRACH resource is greater than the sum of the numbers of the basic resource units included in the time domain and the frequency domain of the second PRACH resource.

Specifically, the number of basic resource units included in the second PRACH resource is greater than the number of basic resource units included in the first PRACH resource, and may include two ways:

mode 1

In the time domain, the number of the basic resource units included in the second PRACH resource is greater than the number of the basic resource units included in the first PRACH resource.

Specifically, the PRACH resources used for the nth transmission of the random access preamble sequence (or the nth random access procedure) include P time domain resource elements, and the PRACH resources used for the (n + 1) th transmission of the random access preamble sequence (or the (n + 1) th random access procedure) include (P + Q) time domain resource elements. That is, each time the number of transmissions is increased, the PRACH resources used during transmission are increased by Q time domain resource units.

It should be understood that the above description takes the example that the number of the added time domain resource units is the same for every retransmission process. Alternatively, the number of the increased time domain resource units may be different at each retransmission.

For example, the time domain resource used by the 2 nd random access includes (P + Q) time domain resource units, the time domain resource used by the 3 rd random access includes (P +2Q) time domain resource units, and.

Fig. 3 shows a schematic diagram of PRACH resources used by a UE in a random access procedure. As shown in fig. 3, 1 time random access uses 1 time domain resource unit, 2 times random access uses 2 time domain resource units, and 4 times random access uses 4 time domain resource units.

In addition, since the UE should follow the rule of sending after detecting (LBT) when transmitting signals on the unlicensed spectrum resource, once the transmitted signals are interrupted, the UE needs to Listen again. Therefore, preferably, the PRACH resource used by any one random access procedure includes a plurality of time domain resource elements that are consecutive in the time domain.

Optionally, each time domain resource unit is also used for transmitting a Cyclic Prefix (CP) of the random access preamble sequence.

Optionally, the formats of the PRACH channels used by the nth random access and the mth random access are different.

Optionally, when n and m are not equal, since the number of basic resource units included in the PRACH resource used by the nth random access and the mth random access in the time domain is different, it may be considered that the transmission formats corresponding to the random access preamble sequences used by the nth random access and the mth random access are different.

Mode 2

In the frequency domain, the number of the basic resource units included in the second PRACH resource is greater than the number of the basic resource units included in the first PRACH resource.

Specifically, the PRACH resources used for the nth transmission of the random access preamble sequence (or the nth random access procedure) include R frequency domain resource elements, and the PRACH resources used for the (n + 1) th transmission of the random access preamble sequence (or the (n + 1) th random access procedure) include (R + S) frequency domain resource elements. That is, every time the number of transmissions is increased, the PRACH resources used in transmission are increased by S frequency domain resource elements.

For example, the frequency domain Resource corresponding to the system bandwidth is divided into a plurality of frequency domain Resource units, and each frequency domain Resource unit includes a plurality of consecutive Resource Blocks (RBs). The PRACH resource used by the UE for the 2 nd random access occupies (R + S) frequency domain resource units, the PRACH resource used by the 3 rd random access occupies (R +2S) frequency domain resource units, and the PRACH resource used by the kth random access occupies (R + (k-1). S) frequency domain resource units.

Preferably, one frequency domain resource unit includes 6 RBs.

Preferably, one frequency domain resource unit includes 1 RB.

Similarly, the above description takes the example that the number of the added frequency domain resource units is the same for every retransmission process added. Optionally, the number of the increased frequency domain resource units may also be different in each retransmission.

Fig. 4 shows a schematic diagram of PRACH resources used by a UE in a random access procedure. As shown in fig. 4, the system bandwidth is divided into a plurality of frequency domain units, wherein 16 of the 4 UEs shown in fig. 4 (i.e., UE1, UE2, UE3, and UE4) occupy the frequency domain units (i.e., corresponding to reference numerals 0 to 15). Hereinafter, using UE1 as an example, PRACH resources used by UE1 in 4 random access preamble sequence transmissions in one random access procedure will be described. The UE1 uses the frequency domain unit corresponding to the reference numeral 0 in the 1 st random access preamble sequence transmission process, if the 1 st random access fails, the UE1 uses the frequency domain units corresponding to the

reference numerals

0 and 4 in the 2 nd random access preamble sequence transmission process. It can be seen that, each time the transmission frequency is increased, the UE adds a frequency domain unit on the basis of the frequency domain unit occupied by the previous transmission.

Optionally, when n and m are not equal, since the number of basic resource units included in the frequency domain of the PRACH resource used by the nth random access and the mth random access is different, it may be considered that the transmission formats corresponding to the random access preamble sequences used by the nth random access and the mth random access are different.

As described in the foregoing mode 1 and mode 2, according to the method for sending a random access preamble sequence in the embodiment of the present invention, after a transmission failure of the random access preamble sequence, the user equipment increases time domain resources or frequency domain resources used for transmitting the random access preamble sequence in a retransmission process, so that the user equipment can increase copies of the random access preamble sequence by increasing the time domain resources or frequency domain resources used for transmitting the random access preamble sequence in the retransmission process under the condition that the maximum transmit power spectral density is limited, and the base station performs combining and demodulation processing on multiple copies of the random access preamble sequence in the retransmission process, thereby improving the detection performance of the random access preamble sequence.

It should be noted that, compared to using one basic resource unit to transmit one random access preamble sequence, the user equipment adds a time domain resource unit or a frequency domain resource unit for transmitting the random access preamble sequence in the retransmission process, and the random access preamble sequence transmitted on the added time domain resource unit or the added frequency domain resource unit is referred to as a copy of the random access preamble sequence.

Taking fig. 4 as an example, in the 1 st sending process of the random access preamble sequence, the UE1 transmits a random access preamble sequence on the frequency domain resource unit corresponding to the reference numeral 0. If the 1 st random access fails, in the sending process of the 2 nd random access preamble sequence, one random access preamble sequence (i.e. including a copy of the random access preamble sequence) is transmitted on the frequency domain resource units corresponding to the

reference numerals

0 and 4, respectively. Similarly, the 3 rd random access includes two copies of the random access preamble sequence, and the 4 th random access includes three copies of the random access preamble sequence.

Optionally, as an embodiment, the number of basic resource units included in the second PRACH resource is equal to the number of the basic resource units included in the first PRACH resource, at least one basic resource unit included in the first PRACH resource is located in P frequency domain unit groups, and at least one basic resource unit included in the second PRACH resource is located in Q frequency domain unit groups, where each frequency domain unit group includes R consecutive resource blocks RB, P is greater than or equal to 1, Q is greater than P, and R is greater than or equal to 1.

Fig. 5 shows another schematic diagram of PRACH resources used by a UE in a random access procedure. As shown in fig. 5, frequency domain resources corresponding to the system bandwidth are divided into a plurality of frequency domain unit groups, each of which includes a plurality of consecutive RBs (e.g., 6). It is assumed that at least one basic resource unit included in PRACH resources may be located in 6 groups at most. For convenience of description, the 6 groups are sequentially denoted as group #1, group #2, group #3, group #4, group #5, and group #6, each of which includes 6 RBs. The PRACH resource used when the UE transmits the random access preamble sequence 1 st time occupies 1 group (i.e., group #1) therein on the frequency domain, and more specifically, occupies 6 RBs of the group # 1. If the 1 st transmission fails, the UE occupies 2 of the groups (i.e., group #2 and group #6) at the 2 nd transmission, and more particularly, 3 RBs in each group. And if the 2 nd random access preamble sequence transmission also fails, the UE initiates the 3 rd random access preamble sequence transmission to the base station. In the 3 rd transmission of the random access preamble sequence, the PRACH resource used by the UE occupies 3 groups (i.e., group #2, group #4, and group #6) of the above-described plurality of frequency domain unit groups in the frequency domain, and more specifically, occupies 2 RBs in each group. Similarly, if the 3 rd transmission of the random access preamble sequence continues to fail, the PRACH resource used by the UE occupies 4 groups (i.e., group #2, group #3, group #5, and group #6) of the plurality of frequency domain unit groups described above in the frequency domain during the 4 th transmission of the random access preamble sequence, and more particularly, occupies one RB of group #2 and group #6 while occupying 2 RBs of

group #

3 and 2 RBs of group #5, respectively.

It should be noted that each frequency domain unit group shown in fig. 5 only includes 6 RBs as an example, and each frequency domain unit group may include any number of RBs in the embodiment of the present invention. The embodiment of the present invention is not limited thereto.

In view of the limitation of the maximum transmission power density on the unlicensed spectrum resources, in the embodiment of the present invention, after the random access preamble sequence fails to be transmitted for the first time, the transmission power of the random access preamble sequence may be increased by distributing the frequency domain resources for transmitting the random access preamble sequence into different groups in the retransmission process.

Optionally, as an embodiment, at least one of the following conditions is satisfied between the first PRACH resource and the second PRACH resource:

the first PRACH resource and the second PRACH resource are not overlapped on the time domain;

the first PRACH resource and the second PRACH resource do not overlap in a frequency domain.

Specifically, there may be user equipments transmitting the random access preamble sequence m and the random access preamble sequence n at the same time in the system, where m ≠ n. The base station needs to perform combining demodulation according to the resources occupied by the preamble sequence transmission, and because the time-frequency resources occupied by the random access preamble sequences for the mth transmission and the nth transmission are different, the base station also has different processing on the random access preamble sequences for the mth transmission and the nth transmission, and the base station can distinguish the time-frequency resources corresponding to the random access preamble sequences for each transmission.

The time-frequency resources of the mth transmission random access preamble sequence and the nth transmission random access preamble sequence are separated in time domain. Therefore, the base station can determine the basic resource units included in the time domain resource according to different time domain resource positions, and then merge the random access preamble sequences carried on the time domain resource.

It should be understood that, in this embodiment, the first PRACH resource and the second PRACH resource correspond to different UEs, respectively. In other words, PRACH resources used by the nth UE (for convenience of distinction, referred to as UE #1) and the mth UE (for convenience of distinction, referred to as UE #2) may not overlap completely in the time domain or the frequency domain (for the case of overlapping, the following description is provided).

Fig. 6 shows another schematic diagram of PRACH resources used by a UE. As shown in fig. 6, there are 4 UEs performing random access in the system, where UE #1 is the 1 st transmission random access preamble sequence, UE #2 is the 2 nd transmission random access preamble sequence, UE #3 is the 3 rd transmission random access preamble sequence, and UE #4 is the 4 th transmission random access preamble sequence. It can be seen that the PRACH resources used by 4 UEs in the random access procedure are distinguished in the time domain (or, the PRACH resources used by two UEs with different transmission times have no overlapping portion in the time domain).

Fig. 7 shows another schematic diagram of PRACH resources used by a UE. As shown in fig. 7, there are 4 UEs performing random access simultaneously in the system, where UE #1 is the 1 st transmission random access preamble sequence, UE #2 is the 2 nd transmission random access preamble sequence, UE #3 is the 3 rd transmission random access preamble sequence, and UE #4 is the 4 th transmission random access preamble sequence. It can be seen that the PRACH resources used by 4 UEs in the random access procedure are distinguished in the frequency domain (or the PRACH resources used by two UEs with different transmission times are not overlapped in the frequency domain).

Optionally, as an embodiment, at least one of the following conditions is satisfied between the first PRACH resource group and the second PRACH resource group:

the first PRACH resource group and the second PRACH resource group are not overlapped on a time domain;

the first set of PRACH resources is non-overlapping with the second set of PRACH resources in a frequency domain.

Optionally, as an embodiment, when the access network device receives the first random access preamble sequence transmitted by the first terminal device on the first PRACH resource, the method further includes:

the access network device receives a third random access preamble sequence transmitted by the second terminal device on a third PRACH resource, where the third PRACH resource is a PRACH resource that is determined by the second terminal device from the second PRACH resource group and is used for performing random access for an (n + 1) th time, and the third PRACH resource satisfies at least one of the following conditions:

the resources occupied by the third PRACH resource in the time domain at least include the resources occupied by the first PRACH resource in the time domain;

the resources occupied by the third PRACH resource in the frequency domain at least include the resources occupied by the first PRACH resource in the frequency domain.

In the embodiment of the present invention, the PRACH resource (for convenience of distinguishing, referred to as PRACH resource #1) used by the n +1 th UE (for convenience of distinguishing, referred to as UE #1) performing random access may include a PRACH resource (for convenience of distinguishing, referred to as PRACH resource #2) used by the n th UE (for convenience of distinguishing, referred to as UE #2) performing random access. More specifically, PRACH resource #1 may include a resource occupied by PRACH resource #2 in a time domain or a frequency domain. The present embodiment will be described in detail below with reference to fig. 8.

Fig. 8 shows a schematic diagram of PRACH resources used by multiple terminal devices. As shown in fig. 8, assuming that there are multiple terminal devices corresponding to the same frequency band in the process of transmitting the random access preamble sequence (in other words, the same frequency domain resource is used for each transmission of the random access preamble sequence), the access points where the terminal devices start to transmit are different when the random access preamble sequence is transmitted for the nth time. For example, if it is a terminal device that transmits a random access preamble sequence 1 (for the sake of distinction, referred to as terminal device #1), the terminal device #1 may start transmission from symbol 0, symbol 3, symbol 7, and symbol 10. If it is a terminal apparatus which transmits the random access preamble sequence 2 (for the sake of distinction, it is referred to as terminal apparatus #2), terminal apparatus #2 may start transmission from symbol 0 and symbol 7. In the case of the terminal apparatus which transmits the random access preamble sequence 3 (for the sake of distinction, referred to as terminal apparatus #3), the terminal apparatus #3 may start transmission from symbol 0 and symbol 7. If it is a terminal apparatus which transmits the random access preamble sequence 4 (for the sake of distinction, it is referred to as terminal apparatus #4), terminal apparatus #4 may start transmission from symbol 0. Accordingly, the access network device starts demodulating the received random access preamble sequence according to the starting access point of the possible multiple combining.

Optionally, as an embodiment, the distribution form of the first PRACH resources and the second PRACH resources on the frequency domain includes at least one of the following cases:

the frequency domain interval between the first RB and the last RB occupied by the first PRACH resource on the frequency domain is greater than or equal to a preset frequency domain interval;

the frequency domain interval between the first RB and the last RB occupied by the second PRACH resource in the frequency domain is greater than or equal to a preset frequency domain interval.

It should be understood that certain countries or regions dictate that when a communication device (e.g., a UE) uses unlicensed spectrum resources, the proportion of the system bandwidth occupied by the transmitted signal needs to reach a certain threshold (e.g., 80%). In the prior art, PRACH resources used for transmitting the random access preamble sequence occupy 6 consecutive RBs in the frequency domain, and a situation that a ratio of a transmitted signal occupying a system bandwidth does not meet a requirement may occur. Therefore, in the embodiment of the present invention, the PRACH resource allocated by the base station to the UE for transmitting the random access preamble sequence has a frequency domain interval between the first RB and the last RB in the frequency domain greater than or equal to a preset frequency domain interval.

It should be noted that, in the embodiment of the present invention, specific values of the preset frequency domain interval are not limited at all, and values of the preset frequency domain interval may be determined according to the proportion requirement of different countries or regions for the system bandwidth occupied by the signal or other rules.

Fig. 9 shows a schematic diagram of a distribution manner of PRACH resources used in a random access procedure over a system bandwidth. As shown in fig. 9, taking the requirement that the transmitted signal needs to occupy 80% of the system bandwidth as an example, in the embodiment of the present invention, the PRACH resource used for the nth transmission includes at least one basic resource unit, and occupies a plurality of RBs in total, and the requirement may be satisfied by distributing the first RB and the last RB allocated to the PRACH resource in the frequency domain on two sides of the system bandwidth and spanning 80% of the system bandwidth in the middle (see fig. 9). For another example, in the 1 st random access, it is assumed that the PRACH resource used by the UE includes one basic resource unit, and in order to meet the bandwidth occupation requirement, the 1 basic resource unit includes a plurality of RBs which are discrete in a frequency domain, where a first RB and a last RB in the plurality of RBs occupy 80% of the system bandwidth.

Optionally, as an embodiment, the transmission power used by the terminal device to transmit the second random access preamble sequence on the second PRACH resource is greater than the transmission power used by the terminal device to transmit the first random access preamble sequence on the first PRACH resource.

In the embodiment of the invention, the terminal equipment can firstly increase the transmitting power of the random access preamble sequence in the process of retransmitting the random access preamble sequence, and when the power spectral density of the terminal equipment reaches the power spectral density specified by the regulation, the terminal equipment initiates the random access process by increasing the time-frequency resource mode for transmitting the random access preamble sequence.

It can be understood that, of course, the terminal device may also initiate the random access procedure to the access network device by increasing the time-frequency resource manner for sending the random access preamble sequence when the limited power spectral density is not reached. The embodiment of the present invention is not particularly limited thereto.

Optionally, as an embodiment, the second random access preamble sequence is the first random access preamble sequence.

It should be understood that when the UE initiates the random access procedure to the base station for the first time, it needs to determine a random access preamble sequence (for the sake of convenience of distinction, it is referred to as random access preamble sequence #1) from available multiple random access preamble sequences. Next, the UE transmits a random access preamble sequence #1 to the base station. If the 1 st random access is not successful, the UE initiates a 2 nd random access process (or retransmits a random access preamble sequence) to the base station. Generally, the UE will continue to transmit the random access preamble sequence determined in the previous random access procedure during the retransmission procedure, i.e. the second random access preamble sequence is the first random access preamble sequence. However, in the embodiment of the present invention, the UE may also re-determine a new random access preamble sequence (for convenience of distinction, referred to as random access preamble sequence #2) during the retransmission process, where the random access preamble sequence #1 is different from the random access preamble sequence # 2.

105. And the terminal equipment sends the second random access preamble sequence on the second PRACH resource.

Optionally, in the embodiment of the present invention, step 106 may also be included.

106. When the access network device detects the second random access preamble sequence on the second PRACH resource, the access network device calculates a random access wireless network temporary identifier corresponding to the second PRACH resource according to a time domain or a frequency domain included in the second PRACH resource, and sends a random access response to the first terminal device according to the random access wireless network temporary identifier.

Because the second PRACH resource includes at least one basic resource unit, when the second PRACH resource includes one basic resource unit, optionally, the access network device calculates the random access radio network temporary identifier corresponding to the second PRACH resource according to the time domain or frequency domain position of the first RB occupied by the basic resource unit.

When the second PRACH resource includes more than one basic resource unit, optionally, the access network device calculates, according to a time domain or a frequency domain position of a part of the basic resource units included in the second PRACH resource, a random access radio network temporary identifier corresponding to the second PRACH resource. For example, the access network device calculates a random access radio network temporary identifier corresponding to the second PRACH resource according to a time domain or frequency domain position of a first RB occupied by a first basic resource unit included in the second PRACH resource; or the access network device calculates the random access wireless network temporary identifier corresponding to the second PRACH resource according to the time domain or frequency domain position of the first RB occupied by the last basic resource unit included in the second PRACH resource.

The method for transmitting the random access preamble sequence according to the embodiment of the present invention is described in detail above with reference to fig. 1 to 9. A terminal device and an access network device for transmitting a random access preamble sequence according to an embodiment of the present invention are described below with reference to fig. 10 and 11.

Fig. 10 shows a schematic block diagram of a terminal device 300 according to an embodiment of the present invention. As shown in fig. 10, the terminal device 300 includes a determination unit 310 and a transmission unit 320, wherein,

a processing unit 310, configured to determine a first random access preamble sequence, and determine a first PRACH resource from a first physical random access channel PRACH resource group, where the first PRACH resource group includes at least one PRACH resource for performing nth random access, the first PRACH resource includes at least one basic resource unit, and the basic resource unit can bear all information of the random access preamble sequence transmitted to an access network device by the terminal device in a random access process, where n is greater than or equal to 1;

a sending unit 320, configured to transmit the first random access preamble sequence on the first PRACH resource;

the processing unit 310 is further configured to determine a second random access preamble sequence when the random access procedure using the first random access preamble sequence fails, and determine a second PRACH resource from a second PRACH resource group, where the second PRACH resource group includes at least one PRACH resource for performing n +1 th random access, the second PRACH resource includes at least one basic resource unit, and the number of the basic resource units included in the second PRACH resource is greater than or equal to the number of the basic resource units included in the first PRACH resource;

the transmitting unit 320 is further configured to transmit the second random access preamble sequence on the second PRACH resource.

Optionally, as an embodiment, the number of basic resource units included in the second PRACH resource is greater than the number of basic resource units included in the first PRACH resource, where the number of basic resource units included in the second PRACH resource includes at least one of the following cases:

Optionally, as an embodiment, the number of basic resource units included in the second PRACH resource is equal to the number of basic resource units included in the first PRACH resource, at least one basic resource unit included in the first PRACH resource is located in P frequency domain unit groups, and at least one basic resource unit included in the second PRACH resource is located in Q frequency domain unit groups, where each frequency domain unit group includes R consecutive resource blocks RB, P is greater than or equal to 1, Q is greater than P, and R is greater than or equal to 1.

the first PRACH resource is non-overlapping with the second PRACH resource in a time domain;

the N RBs are contiguous in the frequency domain;

at least two RBs of the N RBs are discontinuous;

Optionally, as an embodiment, the distribution form of the first PRACH resource and the second PRACH resource on the frequency domain includes at least one of the following cases:

Optionally, as an embodiment, the determining unit 310 is specifically configured to determine the first random access preamble sequence from a first random access preamble sequence group, where the first random access preamble sequence group includes at least one random access preamble sequence used for nth random access;

the processing unit 310 is further specifically configured to determine a second random access preamble sequence from a second random access preamble sequence group, where the second random access preamble sequence group includes at least one random access preamble sequence used for n +1 th random access, and the first random access preamble sequence group is different from the random access preamble sequence included in the second random access preamble sequence group.

Optionally, as an embodiment, the second random access preamble sequence is the same as the first random access preamble sequence.

Optionally, as an embodiment, the method further includes:

and the terminal equipment receives the random access response sent by the access network equipment according to the random access wireless network temporary identifier.

The terminal device 300 transmitting the random access preamble sequence according to an embodiment of the present invention may correspond to a terminal device in the method of transmitting the random access preamble sequence according to an embodiment of the present invention. Also, the units in the terminal device 300 and the other operations and/or functions described above are respectively for realizing the steps performed by the terminal device in fig. 2. For brevity, no further description is provided herein.

Fig. 11 shows a schematic block diagram of an access network apparatus 400 according to an embodiment of the invention. As shown in fig. 11, the access network apparatus 400 includes a processing unit 410 and a receiving unit 420, wherein,

a processing unit 410, configured to configure multiple physical random access channel PRACH resource groups, where a first PRACH resource group in the multiple PRACH resource groups includes at least one PRACH resource for performing random access for an nth time, a second PRACH resource group in the multiple PRACH resource groups includes at least one PRACH resource for performing random access for an n +1 th time, each PRACH resource in the first PRACH resource group and the second PRACH resource group includes at least one basic resource unit, the basic resource unit is capable of at least bearing all information of a random access preamble sequence transmitted to the access network device by a terminal device in a random access process, the number of basic resource units included in the second PRACH resource is greater than or equal to the number of basic resource units included in the first PRACH resource, and n is greater than or equal to 1;

a receiving unit 420, configured to receive, at a first time interval, a first random access preamble sequence transmitted by a first terminal device on a first PRACH resource, where the first PRACH resource is determined by the first terminal device from the first PRACH resource group;

the receiving unit 420 is further configured to receive, after the random access procedure that the first terminal device uses the first random access preamble sequence fails, a second random access preamble sequence that is transmitted by the first terminal device on a second PRACH resource, where the second PRACH resource is determined by the first terminal device from the second PRACH resource group.

Optionally, as an embodiment, the number of basic resource units included in the second PRACH resource is greater than or equal to the number of basic resource units included in the first PRACH resource, where the number of basic resource units included in the first PRACH resource includes at least one of:

the number of the basic resource units included in the second PRACH resource in the time domain is greater than the number of the basic resource units included in the first PRACH resource in the time domain;

Optionally, as an embodiment, the receiving unit is further configured to:

receiving a third random access preamble sequence transmitted by a second terminal device on a third PRACH resource, where the third PRACH resource is a PRACH resource that is determined by the second terminal device from the second PRACH resource group and is used for performing random access for an n +1 th time, and the third PRACH resource satisfies at least one of the following conditions:

the N RBs are contiguous in the frequency domain;

at least two RBs of the N RBs are discontinuous;

the frequency domain interval between the first RB and the last RB which are allocated to the first PRACH resource by the access network equipment on the frequency domain is larger than or equal to a preset frequency domain interval;

the frequency domain interval between the first RB and the last RB allocated to the second PRACH resource by the access network device on the frequency domain is greater than or equal to a preset frequency domain interval.

Optionally, as an embodiment, the transmission power used by the first terminal device to transmit the second random access preamble sequence on the second PRACH resource is greater than the transmission power used by the first terminal device to transmit the first random access preamble sequence on the first PRACH resource.

Optionally, as an embodiment, the processing unit 410 is further configured to,

configuring a plurality of random access preamble sequence groups, wherein random access preamble sequences included in any two random access preamble sequences are different, a first random access preamble sequence group in the plurality of random access preamble sequence groups comprises at least one sequence used for performing nth random access, a second random access preamble sequence group in the plurality of random access preamble sequence groups comprises at least one sequence used for performing n +1 th random access, and the first random access preamble sequence group is different from the second random access preamble sequence group.

Optionally, as an embodiment, the processing unit is specifically configured to, when the second random access preamble sequence is detected on the second PRACH resource, determine a random access radio network temporary identifier corresponding to the second PRACH resource according to a time domain or a frequency domain position of a basic resource unit included in the second PRACH resource;

the sending unit is specifically configured to send a random access response to the first terminal device.

The access network device 400 for transmitting the random access preamble sequence according to the embodiment of the present invention may correspond to an access network device in the method for transmitting the random access preamble sequence according to the embodiment of the present invention. Also, the various elements and other operations and/or functions described above in the access network apparatus 400 are each intended to implement the various steps performed by the access network apparatus in fig. 2. For brevity, no further description is provided herein.

The terminal device and the access network device for transmitting the random access preamble sequence according to the embodiment of the present invention are described in detail above with reference to fig. 10 and 11. An apparatus for transmitting a random access preamble sequence according to an embodiment of the present invention is described below with reference to fig. 12 and 13.

Fig. 12 shows a schematic block diagram of a terminal device 500 according to an embodiment of the present invention. As shown in fig. 12, the terminal device 500 includes a processor 510, a transceiver 520, and a memory 530. Optionally, the device 500 further comprises a bus system 540, wherein the processor 510, the transceiver 520 and the memory 530 may be connected via the bus system 540. Memory 530 may be used to store instructions, processor 510 may be used to execute instructions stored by memory 530,

the system comprises a first random access preamble sequence, a second random access preamble sequence and a third random access channel, wherein the first random access preamble sequence is used for determining a first PRACH resource from a first physical random access channel PRACH resource group, the first PRACH resource group comprises at least one PRACH resource used for performing nth random access, the first PRACH resource comprises at least one basic resource unit, and the basic resource unit can bear all information of the random access preamble sequence transmitted to the access network equipment by the terminal equipment in one random access process, wherein n is more than or equal to 1;

a transceiver 520 configured to transmit the first random access preamble sequence on the first PRACH resource;

the processor 510 is further configured to, when a random access procedure using the first random access preamble sequence fails, determine a second random access preamble sequence, and determine a second PRACH resource from a second PRACH resource group, where the second PRACH resource group includes at least one PRACH resource configured by the access network device and used for performing random access for an n +1 th time, the second PRACH resource includes at least one basic resource unit, and the number of the basic resource units included in the second PRACH resource is greater than or equal to the number of the basic resource units included in the first PRACH resource;

the transceiver 520 is also configured to transmit the second random access preamble sequence on the second PRACH resource.

the N RBs are contiguous in the frequency domain;

at least two RBs of the N RBs are discontinuous;

Optionally, as an embodiment, the transmission power used by the device to transmit the second random access preamble sequence on the second PRACH resource is greater than the transmission power used by the device to transmit the first random access preamble sequence on the first PRACH resource.

Optionally, as an embodiment, the processor 510 is specifically configured to determine the first random access preamble sequence from a first random access preamble sequence group, where the first random access preamble sequence group includes at least one random access preamble sequence used for nth random access;

the processor 510 is further specifically configured to determine a second random access preamble sequence from a second random access preamble sequence group, where the second random access preamble sequence group includes at least one random access preamble sequence used for n +1 th random access, and the first random access preamble sequence group is different from the random access preamble sequence included in the second random access preamble sequence group.

Optionally, as an embodiment, the processor 510 is specifically configured to determine, according to a time domain or a frequency domain position of a basic resource unit included in the second PRACH resource, a random access radio network temporary identifier corresponding to the second PRACH resource;

the transceiver 520 is specifically configured to receive a random access response sent by the access network device according to the random access radio network temporary identifier.

It should be understood that in embodiments of the present invention, processor 510 may be a Central Processing Unit (CPU), and processor 510 may also be other general purpose processors, Digital Signal Processors (DSPs), Application Specific Integrated Circuits (ASICs), off-the-shelf programmable gate arrays (FPGAs) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.

Memory 530 may include both read-only memory and random-access memory, and provides instructions and data to processor 510. A portion of processor 510 may also include non-volatile random access memory. For example, processor 510 may also store information of the device type.

The bus system 540 may include a power bus, a control bus, a status signal bus, and the like, in addition to the data bus. For clarity of illustration, however, the various buses are labeled as bus system 540 in the figures.

In implementation, the steps of the above method may be performed by integrated logic circuits of hardware or instructions in the form of software in the processor 510. The steps of the method for sending the random access preamble sequence disclosed by the embodiment of the invention can be directly embodied as the execution of a hardware processor, or the execution of the steps can be completed by the 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 the memory 530, and the processor 510 reads the information in the memory 530 and performs the steps of the above method in combination with the hardware thereof. To avoid repetition, it is not described in detail here.

The device 500 for transmitting a random access preamble sequence according to the embodiment of the present invention may correspond to a terminal device in the method for transmitting a random access preamble sequence according to the embodiment of the present invention. Also, the various elements and other operations and/or functions described above in the device 500 are each intended to implement the various steps performed by the terminal device in fig. 2. For brevity, no further description is provided herein.

Fig. 13 shows a schematic structural block diagram of an access network device according to another embodiment of the present invention. As shown in fig. 13, the access network apparatus 600 includes a processor 610, a transceiver 620, and a memory 630. Optionally, the device 600 further comprises a bus system 640, wherein the processor 610, the transceiver 620, and the memory 630 may be coupled via the bus system 640, wherein the memory 630 may be configured to store instructions, wherein the processor 610 is configured to execute instructions stored by the memory 630,

the transceiver 620 is configured to receive a second random access preamble sequence sent by a first terminal device on a second PRACH resource, where the second random access preamble sequence is sent to an access network device after a failure of sending a first random access preamble sequence to the access network device by the first terminal device on a first PRACH resource, where the first PRACH resource is determined by the first terminal device from a first PRACH resource group, the first PRACH resource includes at least one PRACH resource for performing random access for an nth time, the first PRACH resource includes at least one basic resource unit, the second PRACH resource is determined by the first terminal device from a second PRACH resource group, the second PRACH resource includes at least one PRACH resource for performing random access for an n +1 th time, the second PRACH resource includes at least one basic resource unit, and the number of the basic resource units included in the second PRACH resource is greater than or equal to that of the basic resource units included in the first PRACH resource And (4) counting.

Optionally, as an embodiment, transceiver 620 is also used to,

when receiving a first random access preamble sequence transmitted by a first terminal device on a first PRACH resource, receiving a third random access preamble sequence transmitted by a second terminal device on a third PRACH resource, where the third PRACH resource is a PRACH resource determined by the second terminal device from a second PRACH resource group and used for performing random access for an n +1 th time, and the third PRACH resource satisfies at least one of the following conditions:

the N RBs are contiguous in the frequency domain;

at least two RBs of the N RBs are discontinuous;

the frequency domain interval between the first RB and the last RB allocated to the first PRACH resource by the equipment on the frequency domain is larger than or equal to a preset frequency domain interval;

the frequency domain interval between the first RB and the last RB allocated to the second PRACH resource by the device on the frequency domain is greater than or equal to a preset frequency domain interval.

Alternatively, as one embodiment, processor 610 is configured to,

configuring a plurality of random access preamble sequence groups, wherein random access preamble sequences included in any two random access preamble sequences are different, a first random access preamble sequence group in the plurality of random access preamble sequence groups comprises at least one sequence used for performing nth random access, and a second random access preamble sequence group in the plurality of random access preamble sequence groups comprises at least one sequence used for performing n +1 th random access.

Optionally, as an embodiment, the transceiver 620 is specifically configured to determine, according to a time domain or a frequency domain position of a basic resource unit included in the second PRACH resource, a random access radio network temporary identifier corresponding to the second PRACH resource;

the processor 610 is specifically configured to send a random access response to the first terminal device.

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

Memory 630 may include both read-only memory and random-access memory, and provides instructions and data to processor 610. A portion of the processor 610 may also include non-volatile random access memory. For example, the processor 610 may also store information of the device type.

The bus system 640 may include a power bus, a control bus, a status signal bus, and the like, in addition to a data bus. For clarity of illustration, however, the various buses are designated in the figure as bus system 640.

In implementation, the steps of the above method may be performed by integrated logic circuits of hardware or instructions in the form of software in the processor 610. The steps of the method for sending the random access preamble sequence disclosed by the embodiment of the invention can be directly embodied as the execution of a hardware processor, or the execution of the steps can be completed by the 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 the memory 630, and the processor 610 reads the information in the memory 630 and performs the steps of the above method in combination with the hardware thereof. To avoid repetition, it is not described in detail here.

The apparatus 600 for transmitting a random access preamble sequence according to an embodiment of the present invention may correspond to an access network apparatus in the method of transmitting a random access preamble sequence according to an embodiment of the present invention. Moreover, each unit and the other operations and/or functions in the device 600 are respectively for implementing the corresponding process executed by the access network device in fig. 2, and are not described herein again for brevity.

It should be understood that, in various embodiments of the present invention, 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 on the implementation process of the embodiments of the present invention.

Those of ordinary skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware or combinations of computer software and electronic hardware. 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.

It should be noted that the steps shown in the dashed boxes in the figures represent optional steps.

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 be in an electrical, mechanical or other form.

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.

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 functions, if implemented in the form of software functional units 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 may be embodied in the form of a software product, which is stored in a storage medium and includes 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: a U-disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk, and other various media capable of storing program codes.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and all the changes or substitutions should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.

Claims

1. A method of transmitting a random access preamble sequence, the method comprising:

the method comprises the steps that a terminal device determines a first random access preamble sequence and determines a first PRACH resource from a first physical random access channel PRACH resource group, wherein the first PRACH resource group comprises at least one PRACH resource used for performing nth random access, the first PRACH resource comprises at least one basic resource unit, the basic resource unit can bear all information of the random access preamble sequence transmitted to an access network device by the terminal device in one random access process, and n is more than or equal to 1;

the terminal equipment sends the first random access preamble sequence on the first PRACH resource;

when the random access process using the first random access preamble sequence fails, the terminal device determines a second random access preamble sequence and determines a second PRACH resource from a second PRACH resource group, where the second PRACH resource group includes at least one PRACH resource for performing random access for an (n + 1) th time, the second PRACH resource includes at least one basic resource unit, and the number of the basic resource units included in the second PRACH resource is greater than or equal to the number of the basic resource units included in the first PRACH resource;

the terminal device transmits the second random access preamble sequence on the second PRACH resource,

the number of basic resource units included in the second PRACH resource is equal to the number of basic resource units included in the first PRACH resource, at least one basic resource unit included in the first PRACH resource is located in P frequency domain unit groups, and at least one basic resource unit included in the second PRACH resource is located in Q frequency domain unit groups, where each frequency domain unit group includes R consecutive resource blocks RB, P is greater than or equal to 1, Q is greater than P, and R is greater than or equal to 1.

2. The method of claim 1, wherein the second PRACH resource comprises a greater number of basic resource elements than the first PRACH resource comprises at least one of:

3. The method according to claim 1 or 2, characterised in that at least one of the following conditions is fulfilled between the first PRACH resource and the second PRACH resource:

the first PRACH resource and the second PRACH resource are not overlapped on a time domain;

the first PRACH resource and the second PRACH resource are non-overlapping in a frequency domain.

4. The method of claim 1, wherein the basic resource unit comprises N RBs in frequency domain, N ≧ 2, the positional relationship of the N RBs comprising at least one of:

the N RBs are contiguous in the frequency domain;

at least two RBs of the N RBs are discontinuous;

the frequency domain interval between any two adjacent RBs in the N RBs is equal.

5. The method of claim 1, wherein a distribution pattern of the first PRACH resource and the second PRACH resource in a frequency domain comprises at least one of:

and the frequency domain interval between the first RB and the last RB occupied by the second PRACH resource on the frequency domain is greater than or equal to a preset frequency domain interval.

6. The method of claim 1, wherein the terminal device determines the first random access preamble sequence, comprising:

the terminal device determines a first random access preamble sequence from a first random access preamble sequence group in a plurality of random access preamble sequence groups configured by an access network device, wherein random access preamble sequences included in any two random access preamble sequence groups are different, the random access preamble sequence groups correspond to a plurality of sequence detection formats in a one-to-one manner, each sequence detection format is used for detecting a random access preamble sequence in the corresponding random access preamble sequence group, and the first random access preamble sequence group includes at least one random access preamble sequence for nth random access of the terminal device;

and the terminal device determines a second random access preamble sequence, including:

the terminal device determines a second random access preamble sequence from a second random access preamble sequence group in a plurality of random access preamble sequence groups configured by an access network device, wherein the second random access preamble sequence group includes at least one random access preamble sequence used for the n +1 th random access of the terminal device.

7. The method of claim 1, wherein the second random access preamble sequence is the same as the first random access preamble sequence.

8. The method of claim 1, further comprising:

9. A method of receiving a random access preamble sequence, the method comprising:

an access network device receives a second random access preamble sequence sent by a first terminal device on a second PRACH resource, wherein the second random access preamble sequence is sent to the access network device after the first random access preamble sequence sent by the first terminal device to the access network device fails on a first PRACH resource, the first PRACH resource is determined by the first terminal device from a first PRACH resource group, the first PRACH resource group comprises at least one PRACH resource used for performing nth random access, the first PRACH resource comprises at least one basic resource unit, the second PRACH resource is determined by the first terminal device from a second PRACH resource group, the second PRACH resource group comprises at least one PRACH resource used for performing n +1 th random access, and the second PRACH resource comprises at least one basic resource unit, the number of the basic resource units included in the second PRACH resource is greater than or equal to the number of the basic resource units included in the first PRACH resource,

10. The method of claim 9, wherein the second PRACH resource comprises a greater number of basic resource elements than the first PRACH resource comprises at least one of:

11. The method according to claim 9 or 10, characterised in that at least one of the following conditions is fulfilled between the first PRACH resource and the second PRACH resource:

12. The method of claim 9, wherein when the access network device receives a first random access preamble sequence sent by the first terminal on a first PRACH resource, the method further comprises:

the access network device receives a third random access preamble sequence transmitted by a second terminal device on a third PRACH resource, where the third PRACH resource is a PRACH resource determined by the second terminal device from the second PRACH resource group and used for performing random access for an (n + 1) th time, and the third PRACH resource satisfies at least one of the following conditions:

the resources occupied by the third PRACH resource in the time domain at least comprise the resources occupied by the first PRACH resource in the time domain;

13. The method of claim 9, wherein the basic resource unit comprises N RBs in frequency domain, N ≧ 2, the positional relationship of the N RBs comprising at least one of:

the N RBs are contiguous in the frequency domain;

at least two RBs of the N RBs are discontinuous;

14. The method of claim 9, wherein a distribution pattern of the first PRACH resource and the second PRACH resource in a frequency domain comprises at least one of:

the frequency domain interval between the first RB and the last RB which are allocated to the first PRACH resource by the access network equipment on the frequency domain is greater than or equal to a preset frequency domain interval;

and the frequency domain interval between the first RB and the last RB which are allocated to the second PRACH resource by the access network equipment on the frequency domain is greater than or equal to a preset frequency domain interval.

15. The method of claim 9, further comprising:

the access network equipment is configured with a plurality of random access preamble sequence groups, random access preamble sequences in any two random access preamble sequence groups are different, the random access preamble sequence groups are in one-to-one correspondence with a plurality of sequence detection formats, each sequence detection format is used for detecting a random access preamble sequence in the corresponding random access preamble sequence group, a first random access preamble sequence group in the random access preamble sequence groups comprises at least one sequence for performing nth random access, and a second random access preamble sequence group in the random access preamble sequence groups comprises at least one sequence for performing n +1 th random access.

16. The method of claim 9, wherein the second random access preamble sequence is the same as the first random access preamble sequence.

17. The method of claim 9, further comprising:

when the access network equipment detects the second random access preamble sequence on the second PRACH resource, the access network equipment determines a random access wireless network temporary identifier corresponding to the second PRACH resource according to the time domain or frequency domain position of a basic resource unit included in the second PRACH resource;

and the access network equipment sends a random access response to the first terminal equipment.

18. A terminal device, characterized in that the terminal device comprises:

the processing unit is used for determining a first random access preamble sequence and determining a first PRACH resource from a first Physical Random Access Channel (PRACH) resource group, wherein the first PRACH resource group comprises at least one PRACH resource used for performing nth random access, the first PRACH resource comprises at least one basic resource unit, and the basic resource unit can bear all information of the random access preamble sequence transmitted to access network equipment by the terminal equipment in one random access process, and n is more than or equal to 1;

a sending unit, configured to send the first random access preamble sequence on the first PRACH resource;

the processing unit is further configured to determine a second random access preamble sequence and determine a second PRACH resource from a second PRACH resource group when a random access procedure using the first random access preamble sequence fails, where the second PRACH resource group includes at least one PRACH resource for performing random access for an (n + 1) th time, the second PRACH resource includes at least one basic resource unit, and the number of the basic resource units included in the second PRACH resource is greater than or equal to the number of the basic resource units included in the first PRACH resource;

the transmitting unit is further configured to transmit the second random access preamble sequence on the second PRACH resource,

19. The terminal device of claim 18, wherein the number of basic resource elements included in the second PRACH resource is greater than the number of basic resource elements included in the first PRACH resource, and includes at least one of:

20. The terminal device of claim 18 or 19, wherein at least one of the following conditions is satisfied between the first PRACH resource and the second PRACH resource:

21. The terminal device of claim 18, wherein the basic resource unit comprises N RBs in frequency domain, N ≧ 2, the positional relationship of the N RBs comprising at least one of:

the N RBs are contiguous in the frequency domain;

at least two RBs of the N RBs are discontinuous;

22. The terminal device of claim 18, wherein a distribution form of the first PRACH resource and the second PRACH resource in a frequency domain comprises at least one of:

23. The terminal device of claim 18, wherein the processing unit is specifically configured to determine the first random access preamble sequence from a first random access preamble sequence group, where the first random access preamble sequence group includes at least one random access preamble sequence used for nth random access by the terminal device;

the processing unit is further specifically configured to determine a second random access preamble sequence from a second random access preamble sequence group, where the second random access preamble sequence group includes at least one random access preamble sequence used for n +1 th random access of the terminal device, and the first random access preamble sequence group is different from the random access preamble sequence included in the second random access preamble sequence group.

24. The terminal device of claim 18, wherein the second random access preamble sequence is the same as the first random access preamble sequence.

25. The terminal device of claim 18, wherein the terminal device further comprises:

the processing unit is specifically configured to determine, according to a time domain or frequency domain position of a basic resource unit included in the second PRACH resource, a radio network temporary identifier corresponding to the second PRACH resource, where the second random access is sent to the terminal device by the access network device when the access network device detects the second random access sequence on the second PRACH resource;

and the receiving unit is used for receiving the random access response sent by the access network equipment according to the random access wireless network temporary identifier.

26. An access network device, characterized in that the access network device comprises:

a receiving unit, configured to receive a second random access preamble sequence sent by a first terminal device on a second PRACH resource, where the second random access preamble sequence is sent to an access network device after a failure of sending a first random access preamble sequence to the access network device by the first terminal device on a first PRACH resource, the first PRACH resource is determined by the first terminal device from a first PRACH resource group, the first PRACH resource includes at least one PRACH resource used for performing random access for an nth time, the first PRACH resource includes at least one basic resource unit, the second PRACH resource is determined by the first terminal device from a second PRACH resource group, the second PRACH resource includes at least one PRACH resource used for random access for an n +1 th time, and the second PRACH resource includes at least one basic resource unit, the number of the basic resource units included in the second PRACH resource is greater than or equal to the number of the basic resource units included in the first PRACH resource,

27. The access network device of claim 26, wherein the second PRACH resource includes a greater number of basic resource elements than the first PRACH resource includes at least one of:

28. The access network device of claim 26 or 27, wherein at least one of the following conditions is satisfied between the first PRACH resource and the second PRACH resource:

29. The access network device of claim 26, wherein the receiving unit is further configured to:

receiving a third random access preamble sequence sent by a second terminal device on a third PRACH resource, where the third PRACH resource is a PRACH resource that is determined by the second terminal device from the second PRACH resource group and is used for performing random access for an n +1 th time, and the third PRACH resource satisfies at least one of the following conditions:

30. The access network device of claim 26, wherein the basic resource unit comprises N RBs in frequency domain, N ≧ 2, the positional relationship of the N RBs comprising at least one of:

the N RBs are contiguous in the frequency domain;

at least two RBs of the N RBs are discontinuous;

31. The access network device of claim 26, wherein the distribution of the first PRACH resources and the second PRACH resources over a frequency domain comprises at least one of:

32. The access network device of claim 26, comprising:

a processing unit, configured to configure multiple random access preamble sequence groups, where a first random access preamble sequence group in the multiple random access preamble sequence groups includes at least one sequence for performing nth random access, a second random access preamble sequence group in the multiple random access preamble sequence groups includes at least one sequence for performing n +1 th random access, and the first random access preamble sequence group is different from the second random access preamble sequence group.

33. The access network device of claim 26, wherein the second random access preamble sequence is the first random access preamble sequence.

34. The access network device of claim 26, comprising:

a processing unit, configured to determine, when the second random access preamble sequence is detected on the second PRACH resource, a random access radio network temporary identifier corresponding to the second PRACH resource according to a time domain position or a frequency domain position of a basic resource unit included in the second PRACH resource;

a sending unit, configured to send a random access response to the first terminal device.