WO2019120176A1 - Method for receiving system information and terminal device - Google Patents

Abstract

A method for receiving system information and a terminal device. The method comprises: the terminal device sends a system information block (SIB)-on-demand request to a network device, the SIB-on-demand request comprising an identifier of at least one SIB demanded by the terminal device; the terminal device obtains, in at least one first time period, downlink control information sent by the network device and used for indicating a time frequency resource corresponding to a first SIB in the at least one SIB, the start time point of the first time period being earlier than or equal to the time point when the terminal device receives confirmation information replied by the network device for the SIB-on-demand request. By means of the present application, the receiving delay of the SIB on demand can be shortened.

Description

System message receiving method and terminal device Technical field

The present application relates to the field of wireless communications technologies, and in particular, to a system message receiving method and a terminal device.

Background technique

In the fifth generation (5G) new radio (NR) system, the terminal device can receive system information (SI) broadcast by a next-generation Node B (gNB). The SI is divided into a minimum SI (Minimum SI) and other SI (Other SI), and the Other SI is a collection of multiple System Information Blocks (SIBs). Minimum SI is sent by broadcast. Other SI is sent by broadcast or on-demand.

When the SIB adopts the broadcast transmission mode, the SIB is always broadcast and transmitted in the corresponding reception time window. When the SIB adopts the on-demand transmission mode, if there is no terminal device to order the SIB, the SIB is not sent in the corresponding receiving time window. If the terminal device orders the SIB and the gNB confirms, the SIB is in the corresponding receiving time. The window broadcasts a transmission that continues for one or more reception time windows. Referring to Figure 1, a schematic diagram of the transmission of an on-demand system message (SI) is shown. The receiving time window (SI Window) in the figure represents the receiving time window corresponding to a certain SIB. When there is no terminal device to order the SIB (the first two receiving time windows in FIG. 1), the SIB is not transmitted in the receiving time window. When the terminal device clicks on the SIB (that is, the time point T1 in FIG. 1 initiates an on-demand SI request, which may be characterized as a request for ordering one or a few SIBs), the corresponding receiving time window starts broadcasting the SIB (FIG. 1). The two receiving time windows, that is, the receiving time window 3 and the receiving time window 4) are continued, and the SIB is not continuously transmitted in the receiving time window.

The terminal device can order one or more SIBs required by means of random access. The on-demand request information carries an on-demand SIB list, and is notified to the gNB through Msg1 or Msg3 of the random access procedure. After receiving the on-demand request information of the terminal device, the gNB replies the confirmation information to the terminal device through the Msg2 (Msg1 carrying the on-demand request information scenario) or the Msg4 (the Msg3 carrying the on-demand request information). The gNB then starts broadcasting the SIB in the receiving time window corresponding to the subsequent on-demand SIB. The terminal device that receives the acknowledgment information also synchronizes to receive the on-demand SIB in the receiving time window corresponding to the subsequent on-demand SIB. This process can be seen in Figure 2. In this way, since the random access process implements the request and acknowledgement through two-step or four-step interaction, the delay is large. Moreover, since Msg1 adopts the method of open-loop power control, the probability of failure of a single attempt is high, and multiple attempts are required, and the delay is large. In addition, in the NR multi-beam scenario, due to the beam scanning and the time-varying of the transmit beam and the receive beam pairing, the process delay and the single failure probability are deteriorated, so the reception delay of the on-demand SIB is large. Therefore, how to shorten the receiving delay of the on-demand SIB is a technical problem that needs to be solved at present.

Summary of the invention

The embodiment of the present application provides a system message receiving method and a terminal device, which can shorten the receiving delay of the on-demand SIB.

In a first aspect, the embodiment of the present application provides a system message receiving method, which is applied to a terminal device side. The method includes: the terminal device sends an on-demand request to the network device, where the on-demand request includes an identifier of the at least one SIB that the terminal device orders. The terminal device acquires, by using the network device, downlink control information that is used by the network device to indicate a time-frequency resource corresponding to the first SIB in the at least one SIB, where the start time of the first time period is earlier than or It is equal to the point in time when the terminal device receives the confirmation information that the network device responds to the on-demand request.

With the embodiment of the present application, the terminal device may obtain, in parallel, the downlink control information of the time-frequency resource corresponding to the SIB of the on-demand and the downlink control information of the time-frequency resource corresponding to the acknowledgment information, after the request for the on-demand SIB is initiated. The terminal device does not need to wait for the acknowledgment information of the network device to receive the downlink control information for indicating the time-frequency resource corresponding to the SIB of the on-demand. Compared with the prior art, the terminal device may acquire the time-frequency resource corresponding to the on-demand SIB in advance, and may receive the on-demand SIB in advance, thereby shortening the receiving delay of the on-demand SIB.

In the embodiment of the present application, the first message Msg1 may be a random access preamble, the second message Msg2 may be a random access response, and the third message Msg3 may be an on-demand system message request (On DemandSI Request), the fourth message Msg4 may be an On Demand System Response. The foregoing first message, the second message, the third message, and the fourth message may also have other naming manners, which are not limited in this embodiment of the present application.

Optionally, after the terminal device acquires the downlink control information that is sent by the network device to indicate the time-frequency resource corresponding to the first SIB in the at least one SIB, the terminal device is in the time-frequency corresponding to the first SIB after the at least one first time period is obtained. The first SIB is received on the resource. Compared with the prior art, the terminal device obtains the time-frequency resource corresponding to the on-demand SIB in advance, and can receive the on-demand SIB in advance, thereby shortening the receiving delay of the on-demand SIB.

Optionally, the start time point of the second time period indicated by the time-frequency resource corresponding to the first SIB is earlier than or equal to the time point when the terminal device receives the acknowledgement information that the network device responds to the on-demand request . Compared with the prior art, the terminal device can receive the on-demand SIB in advance, thereby shortening the reception delay of the on-demand SIB.

Optionally, after the terminal device acquires the downlink control information that is sent by the network device to indicate the time-frequency resource corresponding to the first SIB in the at least one SIB, the terminal device acquires the at least one third time period after the at least one first time period is obtained. The downlink control information sent by the network device to indicate the time-frequency resource corresponding to the second SIB in the at least one SIB, where the start time of the third time period is later than the confirmation information that the terminal device receives the response of the network device for the request of the on-demand request Time point. In the embodiment of the present application, after receiving the acknowledgment information sent by the network device, the terminal device may continue to obtain downlink control information for indicating the time-frequency resource corresponding to the SIB that is not received, so as to receive the SIB that is not received.

Optionally, after acquiring, by the network device, the downlink control information that is used by the network device to indicate the time-frequency resource corresponding to the second SIB in the at least one SIB, the terminal device is in the time-frequency corresponding to the second SIB after the at least one third time period is obtained. The second SIB is received on the resource.

Optionally, the terminal device acquires downlink control information that is used by the network device to indicate the time-frequency resource corresponding to the first SIB in the at least one SIB, where the terminal device is in the at least one first time period. De-scrambling the physical downlink control channel PDCCH by using the identifier corresponding to the system message, and acquiring downlink control information that is sent by the network device and used to indicate the time-frequency resource corresponding to the first SIB in the at least one SIB. Optionally, the identifier corresponding to the system message is shared by multiple terminal devices including the terminal device.

For a different terminal device, the identifier corresponding to the system message may be unified. Therefore, the terminal device may use the identifier corresponding to the unified system message to descramble the PDCCH.

Optionally, the identifier corresponding to the system message includes, but is not limited to, an SI-RNTI (Radio Network Temporary Identifier).

Optionally, in the first scenario of the embodiment of the present application, the on-demand request is carried in the first message Msg1, and the confirmation information is carried in the second message Msg2.

In the second scenario of the embodiment of the present application, the on-demand request is carried in the third message Msg3, and the confirmation information is carried in the fourth message Msg4.

In a second aspect, the embodiment of the present application provides a terminal device, where the terminal device includes a plurality of functional units, and is configured to perform a system message provided by any one of the first aspect or the possible implementation manner of the first aspect. Receiving method.

In a third aspect, an embodiment of the present application provides a terminal device, configured to perform the system message receiving method described in the first aspect. The terminal device can include a memory and a processor, a transmitter and a receiver coupled to the memory, wherein: the transmitter is for transmitting a signal to another communication device, such as a network device, the receiver is for Receiving, by the another communication device, such as a network device, a signal for storing an implementation code of a system message receiving method described in the first aspect, the processor for executing a program code stored in the memory, That is, the system message receiving method described in any one of the first aspect or the possible embodiments of the first aspect is performed. Optionally, the processor performs the transmitting by driving or controlling the transmitter when performing a transmitting operation. Optionally, the processor performs the receiving by driving or controlling the receiver when performing a receiving operation.

In a fourth aspect, the embodiment of the present application provides a computer readable storage medium, where the readable storage medium stores instructions, when executed on a computer, causing the computer to execute the system message receiving method described in the first aspect above. .

In a fifth aspect, an embodiment of the present application provides a computer program product comprising instructions, when executed on a computer, causing a computer to execute the system message receiving method described in the first aspect above.

DRAWINGS

In order to more clearly illustrate the technical solutions in the embodiments of the present application or the background art, the drawings to be used in the embodiments of the present application or the background art will be described below.

FIG. 1 is a schematic diagram showing the transmission of an on-demand system message (SI) in the prior art;

2 is a schematic diagram showing a system message block in which a terminal device receives on-demand in the prior art;

FIG. 3 is a schematic structural diagram of a wireless communication system according to an embodiment of the present application;

FIG. 4 is a schematic structural diagram of a terminal device according to some embodiments of the present application;

FIG. 5 is a schematic diagram of a system message block in which a terminal device receives an on-demand broadcast according to an embodiment of the present application;

FIG. 6 is a schematic diagram of a system message block for receiving, by a terminal device, an on-demand system according to an embodiment of the present application;

FIG. 7 is a schematic diagram of another system message block of a terminal device receiving on-demand provided by an embodiment of the present application;

FIG. 8 is a schematic flowchart diagram of a method for receiving a system message according to an embodiment of the present application;

FIG. 9 is a schematic flowchart diagram of another system message receiving method provided by an embodiment of the present application;

FIG. 10 is a schematic flowchart diagram of another system message receiving method provided by an embodiment of the present application;

FIG. 11 is a schematic diagram of Embodiment 1 of a method for receiving a system message according to an embodiment of the present application;

FIG. 12 is a schematic diagram of Embodiment 2 of a method for receiving a system message according to an embodiment of the present application;

FIG. 13 is a schematic diagram of Embodiment 3 of a method for receiving a system message according to an embodiment of the present application;

FIG. 14 is a structural block diagram of a terminal device according to an embodiment of the present application.

Detailed ways

The terms used in the embodiments of the present application are only used to explain the specific embodiments of the present application, and are not intended to limit the present application.

In order to facilitate the understanding of the embodiments of the present application, a wireless communication system according to an embodiment of the present application is first introduced.

Referring to FIG. 3, FIG. 3 illustrates a wireless communication system according to an embodiment of the present application. The wireless communication system 300 can operate in a licensed band or in an unlicensed band. The wireless communication system 300 is not limited to a Long Term Evolution (LTE) system, and may be a future evolved 5G system, an NR system, a Machine to Machine (M2M) system, or the like. As can be appreciated, the use of unlicensed frequency bands can increase the system capacity of the wireless communication system 100. As shown in FIG. 3, the wireless communication system 300 includes one or more network devices 301, one or more terminal devices 303, and a core network 315. among them:

Network device 301 can be used to communicate with terminal device 303 under the control of a network device controller (e.g., a base station controller) (not shown). In some embodiments, the network device controller may be part of the core network 315 or may be integrated into the network device 301.

Network device 301 can be used to transmit control information or user data to core network 315 via a blackhaul interface (e.g., S1 interface) 313.

Network device 301 can communicate wirelessly with terminal device 303 via one or more antennas. Each network device 301 can provide communication coverage for each respective coverage area 307. The coverage area 307 corresponding to the network device 301 can be divided into a plurality of sectors, wherein one sector corresponds to a part of coverage (not shown).

In the embodiment of the present application, the network device 301 may include: a base transceiver station (Base Transceiver Station), a wireless transceiver, a basic service set (BSS), and an extended service set (ESS). Node B, evolved NodeB (eNB or eNodeB), or next-generation Node B (gNB), and so on. The wireless communication system 200 can include several different types of network devices 301, such as a macro base station, a micro base station, and the like. Network device 301 can apply different wireless technologies, such as cell radio access technology, or WLAN radio access technology.

The terminal device 303 can be distributed throughout the wireless communication system 300, either stationary or mobile. In the embodiment of the present application, the terminal device 303 may include: a mobile device, a mobile station, a mobile unit, a wireless unit, a remote unit, a user agent, a mobile client, and the like.

In the embodiment of the present application, the wireless communication system 300 can support multi-carrier (waveform signals of different frequencies) operations. A multi-carrier transmitter can simultaneously transmit modulated signals on multiple carriers. For example, each communication connection 305 can carry multi-carrier signals modulated with different wireless technologies. Each modulated signal can be transmitted on different carriers, and can also carry control information (such as reference signals, control channel information, etc.), overhead information, data, and the like.

In the embodiment of the present application, the network device 301 broadcasts System Information (SI) within its coverage area 307, and the SI content is the same within the coverage 307 of the network device 301. SI is divided into minimum SI (Minimum SI) and other SI (Other SI). Where Other SI is a collection of multiple System Information Blocks (SIBs).

Referring to FIG. 4, FIG. 4 shows a terminal device 400 provided by an embodiment of the present application. As shown in FIG. 4, the terminal device 400 may include: an input and output module (including an audio input and output module 418, a key input module 416, and a display 420, etc.), a user interface 402, one or more processors 404, a transmitter 406, and a receiving device. The device 408, the coupler 410, the antenna 414, and the memory 412. These components can be connected by bus or other means, and FIG. 4 is exemplified by a bus connection. among them:

The antenna 414 can be used to convert electromagnetic energy into electromagnetic waves in free space or to convert electromagnetic waves in free space into electromagnetic energy in a transmission line. The coupler 410 is configured to divide the mobile communication signal received by the antenna 414 into multiple channels and distribute it to a plurality of receivers 408.

Transmitter 406 can be used to perform transmission processing on signals output by processor 404.

Receiver 408 can be used to perform reception processing on the mobile communication signals received by antenna 414.

In the embodiment of the present application, the transmitter 406 and the receiver 408 can be regarded as a wireless modem. In the terminal device 400, the number of the transmitter 406 and the receiver 408 may each be one or more.

In addition to the transmitter 406 and the receiver 408 shown in FIG. 4, the terminal device 400 may further include other communication components such as a GPS module, a Bluetooth module, a Wireless Fidelity (Wi-Fi) module, and the like. The terminal device 400 can also support other wireless communication signals such as satellite signals, short-wave signals, and the like, without being limited to the wireless communication signals described above. Not limited to wireless communication, the terminal device 400 may be configured with a wired network interface (such as a LAN interface) 401 to support wired communication.

The input and output module can be used to implement interaction between the terminal device 400 and the user/external environment, and can mainly include an audio input and output module 418, a key input module 416, a display 420, and the like. Specifically, the input and output module may further include: a camera, a touch screen, a sensor, and the like. The input and output modules communicate with the processor 404 through the user interface 402.

Memory 412 is coupled to processor 404 for storing various software programs and/or sets of instructions. In particular, memory 412 can include high speed random access memory, and can also include non-volatile memory, such as one or more magnetic disk storage devices, flash memory devices, or other non-volatile solid state storage devices. The memory 412 can store an operating system (hereinafter referred to as a system) such as an embedded operating system such as ANDROID, IOS, WINDOWS, or LINUX. The memory 412 can also store a network communication program that can be used to communicate with one or more additional devices, one or more terminal devices, one or more network devices. The memory 412 can also store a user interface program, which can realistically display the content of the application through a graphical operation interface, and receive user control operations on the application through input controls such as menus, dialog boxes, and keys. .

In the embodiment of the present application, the memory 412 can be used to store an implementation program of the system message receiving method provided by one or more embodiments of the present application on the terminal device 400 side. For implementation of the system message receiving method provided by one or more embodiments of the present application, please refer to the subsequent embodiments.

Processor 404 can be used to read and execute computer readable instructions. Specifically, the processor 404 can be used to invoke a program stored in the memory 412. For example, the system message receiving method provided by one or more embodiments of the present application implements the program on the terminal device 400 side, and executes the instructions included in the program. The method involved in the subsequent embodiments is implemented. The processor 404 can support: Global System for Mobile Communication (GSM) (2G) communication, Wideband Code Division Multiple Access (WCDMA) (3G) communication, and Long Term Evolution (Long Term Evolution) One or more of LTE) (4G) communication, and 5G communication, and the like. Alternatively, when the processor 404 sends any message or data, it specifically performs the transmission by driving or controlling the transmitter 406. Alternatively, when the processor 404 receives any message or data, it specifically performs the reception by driving or controlling the receiver 408. Thus, processor 404 can be considered a control center that performs transmission or reception, and transmitter 406 and receiver 408 are the specific executors of the transmitting and receiving operations.

It can be understood that the terminal device 400 can be the terminal device 303 in the wireless communication system 300 shown in FIG. 3, and can be implemented as a mobile device, a mobile station, a mobile unit, a wireless unit, and a remote unit. User agents, mobile clients, and more.

It should be noted that the terminal device 400 shown in FIG. 4 is only one implementation manner of the embodiment of the present application. In an actual application, the terminal device 400 may further include more or less components, which are not limited herein.

The following is a brief description of the embodiments of the present application.

The network device sends the Minimum SI to the terminal device by means of broadcast, and sends the Other SI to the terminal device by means of broadcast or on-demand. The parameters related to Other SI carried in the Minimum SI include: SIB set included in Other SI, SIB transmission mode (broadcast or on-demand), reception time window corresponding to each SIB, and on-demand request information (for example, on-demand SIB list) Type (Msg1 or Msg3). When the SIB adopts the broadcast transmission mode, the SIB is always broadcast and transmitted in the corresponding time window. When the SIB adopts the on-demand transmission mode, if there is no terminal device to order the SIB, the SIB is not sent in the corresponding time window. If the terminal device orders the SIB and the network device confirms, the SIB is in the corresponding time window. The intra broadcast is sent, which is sent for one or more time windows. See Figure 1 for details.

The terminal device in the RRC_IDLE state (Radio Resource Control idle state) or the RRC_INACTIVE state (radio resource control inactive state) requests one or more SIBs required by random access. Specifically, the terminal device may send an on-demand request to the network device by using the first message Msg1 or the third message Msg3 of the random access procedure, where the on-demand request carries a list of SIBs that the terminal device orders. Which message in the random access procedure carries the on-demand request is determined by the parameters in the Minimum SI. After receiving the on-demand request of the terminal device, the network device replies the confirmation information to the terminal device through Msg2 (Msg1 carrying the on-demand request scenario) or Msg4 (the Msg3 carrying the on-demand request scenario). The network device then starts broadcasting the SIB in the time window corresponding to the subsequent on-demand SIB. Considering that the on-demand SIB is broadcasted over a period of time once it is clicked. After initiating the random access procedure of the on-demand SIB, the terminal device may simultaneously attempt to receive the on-demand SIB in the time window corresponding to the on-demand SIB. If the SIB is being broadcasted by the on-demand of other terminal devices in the cell at this time, the terminal device can receive the on-demand SIB in advance, thereby reducing the reception delay.

The downlink message first message Msg2 or the fourth message Msg4 and the on-demand SIB in the random access procedure are all carried on a Physical Downlink Shared Channel (PDSCH). The PDSCH is a shared channel, and its resources (including the time domain, the frequency domain, and the code domain) are dynamically indicated by a Physical Downlink Control Channel (PDCCH). The PDCCH channel can simultaneously indicate multiple resources of the PDSCH channel for carrying different data.

In the embodiment of the present application, the first message Msg1 may be a random access preamble, the second message Msg2 may be a random access response, and the third message Msg3 may be an on-demand system message request (On DemandSI Request), the fourth message Msg4 may be an On Demand System Response. The foregoing first message, the second message, the third message, and the fourth message may also have other naming manners, which are not limited in this embodiment of the present application.

The terminal device de-scrambles the PDCCH by using various identifiers, such as a RNTI (Radio Network Temporary Identifier), to obtain specific time-frequency resource information, and then to solve the Msg2/Msg4/SIB on a specific time-frequency resource, and finally obtains What you need.

When receiving the Msg2, the terminal device monitors the PDCCH channel by using the identifier corresponding to the Msg2. Here, the identifier corresponding to Msg2 includes but is not limited to: RA-RNTI. The identifier corresponding to the Msg2 is not specifically named in the embodiment of the present application. If the PDCCH channel is correctly descrambled by using the identifier corresponding to the Msg2, it indicates that the PDCCH channel indicates the time-frequency resource corresponding to the Msg2 sent by the network device to the terminal device. Therefore, the terminal device will receive Msg2 on the corresponding time-frequency resource.

Similarly, when receiving the Msg4, the terminal device monitors the PDCCH channel by using the identifier corresponding to the Msg4. Here, the identifier corresponding to the Msg4 includes, but is not limited to, the Temporary C-RNTI and the C-RNTI. The identifier corresponding to the Msg4 in the embodiment of the present application is not specifically named. If the PDCCH channel is correctly descrambled by using the identifier corresponding to the Msg4, it indicates that the PDCCH channel indicates the time-frequency resource corresponding to the Msg4 sent by the network device to the terminal device. Therefore, the terminal device will receive Msg4 on the corresponding time-frequency resource.

Similarly, when receiving the SIB, the terminal device monitors the PDCCH channel by using the identifier corresponding to the SI. Here, the identifier corresponding to the SI includes, but is not limited to, the SI-RNTI, and the identifier corresponding to the SI is not specifically named in the embodiment of the present application. If the PDCCH channel is correctly descrambled by using the identifier corresponding to the SI, it indicates that the time-frequency resource corresponding to the SIB broadcasted by the network device is indicated on the PDCCH channel. Therefore, the terminal device receives the SIB on the corresponding time-frequency resource.

The RA-RNTI is used to indicate the Msg2 message in the random access process, and the RA-RNTI can be obtained according to the time-frequency resource location of the physical random access channel (PRACH) of the terminal device. Since the RA-RNTI is determined by the PRACH event itself (the occurrence time, the frequency domain resource, etc.), the values calculated by the terminal device and the network device are the same, and no transmission is required. The Temporary C-RNTI and the C-RNTI are temporary scheduling identifiers allocated by the network device for the terminal device, and are used for further communication between the network device and the terminal device. If the terminal device is in the IDLE mode, it indicates that there is no C-RNTI. If the RRC connection is requested, the network device may allocate a C-RNTI if it agrees in the subsequent Msg4. In the contention mode, the network device sends a Temporary C-RNTI to the terminal device in the Msg2 for the subsequent Msg4 to identify the terminal device. Of course, the terminal device has a C-RNTI or a Temporary C-RNTI. The SI-RNTI is used to parse system messages. The SI-RNTI can be the same as the entire network and is the default value. Therefore, the SI-RNTIs used by different terminal devices may be the same, that is, the SI-RNTIs may be shared by multiple terminal devices. Different terminal devices may use the same SI-RNTI to descramble the PDCCH, thereby determining whether the PDCCH includes control information for indicating the time-frequency resource location of the SIB transmitted by the network device. Each terminal device can simultaneously correspond to multiple RNTIs. The terminal device uses different RNTIs to descramble the PDCCH, acquires the content on the PDCCH, and finally obtains information belonging to itself on the PDSCH.

FIG. 5 is a schematic diagram of a process for a terminal device to monitor a PDCCH according to an embodiment of the present application. As shown in FIG. 5, the terminal device 1 sends an on-demand request to the network device through the Msg1 during the time period T1, where the on-demand request carries the identifier of the SIB3-SIB6. The SIB3 and the SIB4 belong to the same SI, and are assumed to be SI1, and the SIB5 and the SIB6 belong to the same SI, and are assumed to be SI2. Then, the terminal device 1 monitors the PDCCH at the transmission position of the PDCCH by using the Msg2-RNTI, where the transmission location of the PDCCH may be notified to the terminal device 1 when the network device broadcasts the minimum SI, or may be notified to the terminal device 1 by using dedicated signaling. . It is assumed that the terminal device 1 monitors PDCCH1 in the time period T2, and the PDCCH1 indicates the time-frequency resource of the Msg2 that the network device sends to the terminal device 1, and the time-frequency resource is specifically the resource 2 in FIG. Then, when the time domain of the resource 2 arrives, the terminal device 1 receives the Msg2 sent by the network device from the resource 2, and the Msg2 carries the acknowledgement information (Acknowledge, ACK). Then, the terminal device 1 monitors the PDCCH at the transmission position of the PDCCH by using the SI-RNTI, and assumes that the terminal device 1 monitors the PDCCH 2 in the time period T3, and the PDCCH 2 indicates the time-frequency resources of the SIB3 and the SIB4, and the time-frequency resource is specifically shown in FIG. 5. Resources 4 and Resources 5. Then, when the time domain of the resource 4 and the resource 5 arrives, the terminal device 1 receives the SIB3 and the SIB4 transmitted by the network device from the resource 4 and the resource 5. After that, the terminal device 1 continues to monitor the PDCCH at the transmission position of the PDCCH by using the SI-RNTI, and assumes that the terminal device 1 monitors the PDCCH 3 in the time period T5, and the PDCCH 3 indicates the time-frequency resources of the SIB5 and the SIB6, and the time-frequency resource is specifically Resource 6 in 5. Then, when the time domain of the resource 6 arrives, the terminal device 1 receives the SIB5 and the SIB6 transmitted by the network device from the resource 6.

It should be noted that the resource 1 and the resource 3 before the time period T3 in FIG. 5 also carry the SIB3 and the SIB4 sent by the network device, and the process is triggered by another terminal device 2, and the process is triggered by the terminal device 1. The process is similar and will not be repeated. Before the time domain of the resource 1 and the resource 3, the network device also sends downlink control information for indicating the time-frequency resource location of the resource 1 and the resource 3, and the downlink control information is also carried on the PDCCH.

In the embodiment of the present application, after the terminal device 1 sends an on-demand request to the network device through the Msg1, the terminal device 1 can directly monitor the PDCCH by using the SI-RNTI without waiting for the Msg2 replied by the network device, so as to know the SIB corresponding to the on-demand in advance. Time-frequency resources. Specifically, FIG. 6 is a schematic diagram of a process for a terminal device to monitor a PDCCH according to an embodiment of the present application. As shown in FIG. 6, the terminal device 1 sends an on-demand request to the network device through the Msg1 during the time period T1, where the on-demand request carries the identifier of the SIB3-SIB6. After that, the terminal device 1 monitors the PDCCH at the transmission position of the PDCCH by using the Msg2-RNTI, and monitors the PDCCH at the transmission position of the PDCCH by using the SI-RNTI. It is assumed that the terminal device 1 monitors PDCCH1 in the time period T2, and the PDCCH1 indicates the time-frequency resource of the Msg2 that the network device sends to the terminal device 1, and the time-frequency resource is specifically the resource 2 in FIG. Then, the terminal device 1 receives the Msg2 sent by the network device from the resource 2 when the time domain of the resource 2 arrives. Moreover, since another terminal device 2 has requested the SIB3 and the SIB4 to be requested by the network device at this time, the network device selects to transmit the SIB3 and the SIB4 on the resource 1 and the resource 3, and therefore, the network device is in the time domain of the resource 1 and the resource 3. Previously, downlink control information indicating the location of the time-frequency resource of the resource 1 and the resource 3 is transmitted through the PDCCH 2. The terminal device 1 monitors the PDCCH 2 in the time period T3, and learns that the PDCCH 2 indicates the time-frequency resources of the SIB3 and the SIB4, and the time-frequency resources are specifically the resource 1 and the resource 3 in FIG. 6. Then, when the time domain of the resource 1 and the resource 3 arrives, the terminal device 1 receives the SIB3 and the SIB4 transmitted by the network device from the resource 1 and the resource 3. After that, the terminal device 1 continues to monitor the PDCCH at the transmission position of the PDCCH by using the SI-RNTI, and assumes that the terminal device 1 monitors the PDCCH 4 in the time period T6, and the PDCCH 4 indicates the time-frequency resources of the SIB3 and the SIB4, and the time-frequency resource is specifically Resource 4 and Resource 5 in 6. Then, if the terminal device 1 has successfully received the SIB3 and the SIB4, the terminal device 1 may receive the SIB3 and the SIB4 without going to the resource 4 and the resource 5. If the terminal device 1 has not successfully received the SIB3 and the SIB4, the terminal device 1 can receive the SIB3 and the SIB4 on the resource 4 and the resource 5. After that, the terminal device 1 continues to monitor the PDCCH at the transmission position of the PDCCH by using the SI-RNTI, and assumes that the terminal device 1 monitors the PDCCH 3 in the time period T5, and the PDCCH 3 indicates the time-frequency resources of the SIB5 and the SIB6, and the time-frequency resource is specifically FIG. Resources in 6. Then, when the time domain of the resource 6 arrives, the terminal device 1 receives the SIB5 and the SIB6 transmitted by the network device from the resource 6. As can be seen from FIG. 6, the start time point of the time period T3 at which the terminal device 1 monitors the PDCCH for indicating the time-frequency resource of the on-demand SIB is earlier than the time point T4, and therefore, the terminal device 1 can receive the on-demand SIB in advance. Similarly, when the start time point of the time period T3 coincides with the time point T4, the terminal device 1 can also receive the on-demand SIB in advance, as shown in FIG. 7, and details are not described herein again. It should be noted that PDCCH1 and PDCCH2 in FIG. 6 overlap in the time domain. Therefore, PDCCH1 and PDCCH2 can occupy different frequency domains for transmission.

It should be noted that, in FIG. 5 and FIG. 7 , the Msg1 message carries the on-demand request, and the Msg2 message carries the confirmation information as an example. In other implementations, the Msg3 message may also be used to carry the on-demand request, and the Msg4 message carries the Msg4 message. Confirmation information. When the Msg3 message carries the on-demand request, and the Msg4 message carries the acknowledgment information, the process of the PDCCH being monitored by the terminal device 1 is similar to that of FIG. 5 to FIG. 7, and details are not described herein again.

In summary, in the embodiment of the present application, the terminal device monitors the PDCCH channel by using a terminal device identifier (UE ID) combination corresponding to the message. When the resource configuration of the PDSCH channel corresponding to one or two UE IDs is received on the PDCCH channel, the target message is received on the resource of the corresponding PDSCH channel. The two scenarios involved in the embodiment of the present application are introduced to how the terminal device monitors the PDCCH based on the combination of identifiers:

Case 1: The Msg2 and the on-demand SIB are received in parallel: the PDCCH channel is monitored by using the identifier corresponding to the Msg2 and the identifier corresponding to the SI to determine whether the PDCCH channel indicates the time-frequency resource of the Msg2 and/or the time-frequency resource of the SIB. Here, the identifier corresponding to the Msg2 and the identifier corresponding to the SI may refer to the foregoing description, and details are not described herein again.

Case 2: Simultaneously receiving the Msg4 and the on-demand SIB: The PDCCH channel is monitored by using the identifier corresponding to the Msg4 and the identifier corresponding to the SI to determine whether the PDCCH channel indicates the time-frequency resource of the Msg4 and/or the time-frequency resource of the SIB. Here, the identifier corresponding to the Msg4 and the identifier corresponding to the SI may refer to the foregoing description, and details are not described herein again.

It should be noted that the resource 2 for carrying the Msg2 may or may not overlap with the resource for carrying the SIB, and FIG. 5 to FIG. 7 are described by taking the non-overlapping as an example. The time point T4 in FIGS. 5-7 is the end time point at which the terminal device 1 receives the Msg2 transmitted by the network device. In the prior art, the starting time point of the time period T3 at which the terminal device 1 monitors the PDCCH for indicating the time-frequency resource of the on-demand SIB is later than the time point T4. In the embodiment of the present application, the starting time point of the time period T3 of the PDCCH for the terminal device 1 to monitor the time-frequency resource of the on-demand SIB is earlier than or equal to the time point T4.

The foregoing resource 1, resource 3, resource 4, and resource 5 for carrying SIB3 and SIB4 belong to the reception time window of SI1 (SI1 includes SIB3 and SIB4), and these resources do not overlap in the time domain. In addition to resource 1, resource 3, resource 4, and resource 5, there may be other resources for carrying SIB3 and SIB4. Similarly, the resource 6 for carrying SIB5 and SIB6 belongs to the receiving time window of SI2 (SI1 includes SIB5 and SIB6). In addition to resource 6, there may be other resources for carrying SIB5 and SIB6.

A plurality of SIBs that the terminal device requests for on-demand may belong to the same SI or may belong to different SIs. For example, the terminal device 1 in FIG. 6 on-demands SIB3, SIB4, SIB5, and SIB6, where SIB3 and SIB4 belong to SI1, and SIB5 and SIB6 belong to SI2. After receiving the request of the terminal device to request the SIB, the network device may broadcast the complete SI, or may only broadcast the SIB requested by the terminal device. For example, if the terminal device 1 only orders the SIB3, the network device may only send the SIB3 on-demand of the terminal device 1 in the resource 1, the resource 3, the resource 4, and the resource 5, or may also be in the resource 1, the resource 3, the resource 4, and the resource. All SIBs corresponding to SI1 (ie, SIB3 and SIB4) are transmitted within 5. If the Other SI includes multiple SIs, the receiving time windows or resources of the multiple SIs do not overlap in timing, and may have different periods.

The concepts of "time point" and "time period" mentioned in the embodiments of the present application may be specifically characterized as time domain units such as frames, time slots, and symbols during the communication transmission process. For example, the resource 2 carrying Msg2 includes 2 consecutive symbols, which are symbol 1 and symbol 2, respectively. When the terminal device 1 receives the symbol 1 and the symbol 2, it indicates that the terminal device 1 receives the Msg2. In the embodiment of the present application, the end position of the symbol 2 may be defined as the time point when the terminal device receives the Msg2.

Based on the foregoing embodiments of the wireless communication system 300 and the terminal device 400 respectively, the embodiment of the present application provides a system message receiving method. FIG. 8 is a schematic flowchart diagram of a method for receiving a system message according to an embodiment of the present application. As shown in FIG. 8, the system message receiving method includes the following steps.

S801. The terminal device sends an on-demand request to the network device, where the on-demand request includes an identifier of at least one system message block (SIB) that is requested by the terminal device.

S802. The terminal device acquires, by using the network device, downlink control information that is used by the network device to indicate a time-frequency resource corresponding to the first SIB in the at least one SIB, where the start time of the first time period is earlier than or equal to the terminal. The point in time at which the device receives confirmation of the network device's response to the on-demand request.

The downlink control information may be transmitted on the PDCCH. The terminal device acquires downlink control information, which is sent by the network device, for indicating the time-frequency resource corresponding to the first SIB in the at least one SIB, in the at least one first time period, specifically, the terminal device uses the SI-RNTI to descramble the PDCCH, if the descrambling If the PDCCH is successful, it indicates that downlink control information is used to indicate the time-frequency resource of the SIB sent by the network device, and the terminal device acquires the downlink control information from the PDCCH channel. If the SIB sent by the network device is the SIB of the terminal device, the terminal device may obtain the downlink control information of the time-frequency resource corresponding to the SIB for the on-demand, and then go to the corresponding time-frequency resource before receiving the Msg2. The SIB on demand is received in advance. Taking FIG. 6 or FIG. 7 as an example, the SIB of the terminal device 1 on-demand includes SIB3-SIB6. The first SIB is part or all of the SIBs in the SIBs that the terminal device orders, for example, the first SIBs are SIB3 and SIB4. The time-frequency resource corresponding to the first SIB may be the resource 1 and the resource 3 in FIG. 6 or FIG. 7 described above. The first time period may be the time period T3 in FIG. 6 or FIG. 7 described above. The point in time at which the terminal device receives the acknowledgement information of the network device for the on-demand request reply may be the time point T4 in FIG. 6 or FIG. In the embodiment of the present application, the first time period may include one or more.

Optionally, after acquiring, by the network device, the downlink control information that is used by the network device to indicate the time-frequency resource corresponding to the first SIB in the at least one SIB, the terminal device uses the time-frequency resource corresponding to the first SIB after the at least one first time period The first SIB is received. Referring to FIG. 6 or FIG. 7 above, the terminal device 1 receives SIB3 and SIB4 on the resource 1, resource 3.

Optionally, the start time point of the second time period indicated by the time-frequency resource corresponding to the first SIB is earlier than or equal to the time when the terminal device receives the acknowledgement information that the network device responds to the on-demand request reply point. Referring to FIG. 6 above, the second time period includes the time domain corresponding to the resource 1. The terminal device 1 can acquire the on-demand SIB3 and SIB4 in advance before receiving the Msg2.

In the embodiment of the present application, after the terminal device sends an on-demand request to the network device, the terminal device may receive two types of downlink control information in parallel, one is used to indicate downlink control information of the time-frequency resource corresponding to the SIB, and the other is The downlink control information used to indicate the time-frequency resource corresponding to the confirmation information. Therefore, the two processes of the terminal device receiving the on-demand SIB and the terminal device receiving the network device's confirmation information do not have mutual constraints on the time/time domain.

Optionally, after receiving the first SIB on the time-frequency resource corresponding to the first SIB, the terminal device may further determine whether all the SIBs in the on-demand SIB are received. If not, the terminal device acquires downlink control information that is sent by the network device and is used to indicate the time-frequency resource corresponding to the second SIB in the at least one SIB, where the start time of the third time period is late. A point in time at which the terminal device receives the confirmation information that the network device responds to the request for on-demand. The third time period may include the time period T5 in FIG. 6 or FIG. 7. The second SIB is an SIB that has not been received in at least one SIB that is requested by the terminal device. For example, the second SIB includes SIB5 and SIB6 in Fig. 6 or Fig. 7. The time-frequency resource corresponding to the second SIB includes the resource 6 in FIG. 6 or FIG. 7. Furthermore, if the terminal device does not successfully receive the SIB3 and the SIB4 in the resource 1 and the resource 3, the third time period may further include the time period T6 in FIG. 6 or FIG. In this case, the second SIB also includes SIB3 and SIB4. The time-frequency resource corresponding to the second SIB further includes the resource 4 and the resource 5 in FIG. 6 or FIG. 7.

Optionally, after the terminal device acquires the downlink control information that is sent by the network device to indicate the time-frequency resource corresponding to the second SIB in the at least one SIB, the time-frequency resource corresponding to the second SIB by the terminal device, after the at least one third time period is obtained. The second SIB is received. For example, if the second SIB includes SIB5 and SIB6, referring to FIG. 6 or FIG. 7 above, the terminal device 1 receives the SIB5 and the SIB6 on the resource 6.

Optionally, the terminal device acquires downlink control information that is used by the network device to indicate the time-frequency resource corresponding to the first SIB in the at least one SIB, where the terminal device is in the at least one first time period. De-scrambling the physical downlink control channel PDCCH by using the identifier corresponding to the system message, and acquiring downlink control information that is sent by the network device and used to indicate the time-frequency resource corresponding to the first SIB in the at least one SIB. For different terminal devices, the identifier corresponding to the system message may be unified. Therefore, the terminal device may use the identifier corresponding to the unified system message to descramble the PDCCH. Optionally, the identifier corresponding to the system message includes, but is not limited to, an SI-RNTI.

In the first scenario of the embodiment of the present application, the request for the on-demand is sent by the terminal device to the network device by using the first message Msg1, and the confirmation information is sent by the network device to the terminal device by using the second message Msg2. In this case, the terminal device sends an Msg1 to the network device, and the Msg1 carries an on-demand request, that is, an identifier of at least one SIB that the terminal device orders. Then, the terminal device can acquire downlink control information for indicating time-frequency resources corresponding to Msg2 and downlink control information for indicating time-frequency resources corresponding to the SIB of the on-demand. If the terminal device acquires the downlink control information of the time-frequency resource corresponding to the SIB indicating the on-demand, the SIB of the on-demand is received on the time-frequency resource corresponding to the on-demand SIB. If the terminal device obtains downlink control information for indicating the time-frequency resource corresponding to the Msg2, the terminal device receives the Msg2 on the time-frequency resource corresponding to the Msg2. For details of the process, refer to steps S901-S904 in FIG.

In the second scenario of the embodiment of the present application, the request for the on-demand is sent by the terminal device to the network device by using the third message Msg3, and the confirmation information is sent by the network device to the terminal device by using the fourth message Msg4. In this case, before the terminal device sends the request for the on-demand, the terminal device further includes: the terminal device sends the Msg1 to the network device, and the Msg1 may carry the on-demand request, or may not carry the on-demand request. Then, the terminal device can acquire downlink control information for indicating time-frequency resources corresponding to Msg2 and downlink control information for indicating time-frequency resources corresponding to the SIB of the on-demand. If the terminal device acquires the downlink control information of the time-frequency resource corresponding to the SIB indicating the on-demand, the SIB of the on-demand is received on the time-frequency resource corresponding to the on-demand SIB. If the terminal device obtains downlink control information for indicating the time-frequency resource corresponding to the Msg2, the terminal device receives the Msg2 on the time-frequency resource corresponding to the Msg2. After receiving the Msg2, the terminal device determines whether all the SIBs in the on-demand SIB are received. If not, the terminal device sends the Msg3 to the network device, where the Msg3 carries the on-demand request, that is, the identifier of the at least one SIB that the terminal device orders. Then, the terminal device acquires downlink control information for indicating the time-frequency resource corresponding to the Msg4 and downlink control information for indicating the time-frequency resource corresponding to the SIB of the on-demand. If the terminal device acquires the downlink control information of the time-frequency resource corresponding to the SIB indicating the on-demand, the SIB of the on-demand is received on the time-frequency resource corresponding to the on-demand SIB. If the terminal device obtains downlink control information for indicating the time-frequency resource corresponding to the Msg4, the terminal device receives the Msg4 on the time-frequency resource corresponding to the Msg4. For details of the process, refer to steps S1001-S1009 in FIG. The two steps of obtaining the downlink control information for indicating the time-frequency resource corresponding to the Msg2 and obtaining the downlink control information for indicating the time-frequency resource corresponding to the SIB of the on-demand may be simultaneously or different. The execution start time point of the action of ensuring that the terminal device performs the downlink control information for obtaining the time-frequency resource corresponding to the SIB corresponding to the on-demand is earlier than or equal to the time point at which the terminal device receives the Msg2.

For the first scenario, the following describes the execution process of the steps S903 and S904 in FIG. 9 in detail, that is, how to receive the Msg2 and the on-demand after the terminal device obtains the time-frequency resources corresponding to the Msg2 and the on-demand SIB. SIB.

FIG. 11 is a schematic diagram of Embodiment 1 of a method for receiving a system message according to an embodiment of the present application. The process includes but is not limited to the following steps S1101-S1107, wherein:

S1101: The terminal device sends Msg1 to the network device, where the Msg1 includes an identifier of at least one system message block (SIB) that the terminal device requests.

S1102: The next time point arrives, and the terminal device determines whether the next time point is in the time domain corresponding to Msg2. If yes, step S1103 is performed; if not, step 1106 is performed.

Here, the time point refers to a unit in the time domain, which can be specifically characterized as a time domain unit such as a frame, a time slot, and a symbol during a communication transmission.

S1103: The terminal device determines whether the next time point is in the time domain corresponding to the SIB of the on-demand, and if yes, step S1104 is performed; if not, step S1105 is performed.

S1104: The terminal device receives the Msg2 and the on-demand SIB at the next time point.

S1105. The terminal device receives Msg2 at the next time point.

S1106: The terminal device determines whether the next time point is in the time domain corresponding to the SIB of the on-demand, and if yes, executes step S1107; if not, returns to step S1102.

S1107: The terminal device receives the SIB of the on-demand.

Optionally, after step S1107, the following step S1108 is further included.

S1108: The terminal device determines whether all the SIBs in the on-demand SIB are received, and if so, ends the flow; if not, returns to step S1102.

Optionally, after step S1104, the following steps S1109-S1113 are further included.

S1109: The terminal device determines whether all the SIBs in the on-demand SIB are received. If yes, the process ends; if not, step S1110 is performed.

S1110: The terminal device determines whether the desired Msg2 is received. If yes, the random access process ends, step S1111 is performed; if not, step S1112 is performed.

S1111: The terminal device receives the unreceived SIB in a time domain corresponding to the SIB that is not received.

S1112: The terminal device determines whether the reception time window corresponding to Msg2 is completed. If yes, step S1113 is performed; if no, return to step S1102.

After the terminal device sends Msg1, it will wait to receive Msg2. A receiving time window of the Msg2 is set in the random access process. For example, in the LTE system, the receiving time window is a period of time (specifically 3 ms) from the third subframe after the terminal device sends the Msg1, in the NR system. The starting position and duration of the Msg2 receiving time window are not limited here. The network device sends Msg2 in a certain time domain position in the Msg2 receiving time window. When the terminal device has not received the Msg2 after the Msg2 receiving time window, the terminal device resends the Msg1 to re-initiate the random access process.

S1113: The terminal device determines whether the number of attempts to access reaches the threshold number of attempts, and if yes, ends the process; if not, returns to step S1101.

In the embodiment of the present application, the “not received SIB” refers to an SIB in the SIB that the terminal device requests to order, and the terminal device has not received the SIB.

It should be noted that, in this embodiment, the terminal device first determines whether the time point is in the time domain corresponding to Msg2, and then determines whether the time point is in the time domain corresponding to the on-demand SIB. In an actual application, the terminal device may first determine whether the time point is in the time domain corresponding to the SIB of the on-demand, and then determine whether the time point is in the time domain corresponding to the Msg2.

For the foregoing second scenario, the following describes the execution process of steps S1003 and S1004 in FIG. 10 and the execution process of steps S1008 and S1009, that is, the time frequency of the corresponding acquisition of the Msg2 and the on-demand SIB by the terminal device. After the resource, how to receive the Msg2 and the on-demand SIB, and how the terminal device receives the Msg4 and the on-demand SIB after acquiring the time-frequency resources corresponding to the Msg4 and the on-demand SIB.

In this scenario, the two implementation modes are different. The difference is whether the random access procedure is interrupted after the SIB is received in the random access process. There is no difference between the two implementations of the delay in receiving the SIB from the on-demand SIB. However, considering the key performance indicator (KPI) of the random access success rate on the network device side, the random access process can be performed without interruption. The accuracy of the KPI on the network device side. The following two implementations in scenario 2 are described separately.

First implementation

FIG. 12 is a schematic diagram of Embodiment 2 of a method for receiving a system message according to an embodiment of the present application. The process includes but is not limited to the following steps S1201-S1207, wherein:

S1201: The terminal device sends the Msg1 to the network device.

S1202: The next time point arrives, and the terminal device determines whether the next time point is in the time domain corresponding to Msg2. If yes, step S1203 is performed; if not, step 1206 is performed.

Here, the time point refers to a unit in the time domain, which can be specifically characterized as a time domain unit such as a frame, a time slot, and a symbol during a communication transmission.

S1203: The terminal device determines whether the next time point is in a time domain corresponding to the SIB of the on-demand, and if yes, step S1204 is performed; if no, step S1205 is performed.

S1204. The terminal device receives the Msg2 and the on-demand SIB at the next time point.

S1205. The terminal device receives Msg2 at the next time point.

S1206: The terminal device determines whether the next time point is in a time domain corresponding to the SIB of the on-demand, and if yes, step S1207 is performed; if no, returning to step S1202.

S1207. The terminal device receives the SIB of the on-demand.

After step S1207, S1208 is further included.

S1208: The terminal device determines whether all the SIBs in the on-demand SIB are received. If yes, the process ends; if not, the process returns to step S1202.

After step S1204, the following steps S1209-S1219 are further included.

S1209: The terminal device determines whether all the SIBs in the on-demand SIB are received. If yes, the process ends; if not, step S1210 is performed.

S1210: The terminal device determines whether the desired Msg2 is received. If yes, step S1213 is performed; if no, step S1211 is performed.

S1211. The terminal device determines whether the reception time window corresponding to Msg2 is completed. If yes, step S1212 is performed; if no, return to step S1202.

S1212: The terminal device determines whether the number of attempts to access reaches the threshold number of attempts, and if so, ends the process; if not, returns to step S1201.

S1213: The terminal device sends the Msg3 to the network device, where the Msg3 includes an identifier of at least one system message block (SIB) that the terminal device requests.

S1214: The next time point arrives, the terminal device determines whether the next time point is in the time domain corresponding to Msg4, and if yes, step S1215 is performed; if not, step 1218 is performed.

Here, the time point refers to a unit in the time domain, which can be specifically characterized as a time domain unit such as a frame, a time slot, and a symbol during a communication transmission.

S1215: The terminal device determines whether the next time point is in a time domain corresponding to the SIB of the on-demand, and if yes, step S1216 is performed; if no, step S1217 is performed.

S1216. The terminal device receives the Msg4 and the on-demand SIB at the next time point.

S1217. The terminal device receives the Msg4 at the next time point.

S1218: The terminal device determines whether the next time point is in the time domain corresponding to the SIB of the on-demand, and if yes, step S1219 is performed; if no, the process returns to step S1214.

S1219. The terminal device receives the SIB of the on-demand.

After step S1219, S1220 is further included.

S1220: The terminal device determines whether all the SIBs in the on-demand SIB are received, and if so, ends the process; if not, returns to step S1214.

After step S1216, the following steps S1221-S1224 are further included.

S1221: The terminal device determines whether all the SIBs in the on-demand SIB are received, and if so, the process ends; if not, step S1222 is performed.

S1222: The terminal device determines whether the desired Msg4 is received. If yes, the random access procedure ends, step S1223 is performed; if no, step S1224 is performed.

S1223: The terminal device receives the unreceived SIB in a time domain corresponding to the SIB that is not received.

S1224. The terminal device determines whether the reception time window corresponding to Msg4 is completed. If yes, step S1212 is performed; if no, return to step S1214.

It should be noted that, in this embodiment, the terminal device first determines whether the time point is in the time domain corresponding to Msg4, and then determines whether the time point is in the time domain corresponding to the on-demand SIB. In an actual application, the terminal device may first determine whether the next time point is in the time domain corresponding to the on-demand SIB, and then determine whether the time point is in the time domain corresponding to Msg4.

Second implementation

FIG. 13 is a schematic diagram of Embodiment 3 of a method for receiving a system message according to an embodiment of the present application. The process includes but is not limited to the following steps S1301-S1307, wherein:

S1301: The terminal device sends the Msg1 to the network device.

S1302: The next time point arrives, the terminal device determines whether the next time point is in the time domain corresponding to Msg2. If yes, step S1303 is performed; if not, step 1306 is performed.

Here, the time point refers to a unit in the time domain, which can be specifically characterized as a time domain unit such as a frame, a time slot, and a symbol during a communication transmission.

S1303: The terminal device determines whether the next time point is in a time domain corresponding to the SIB of the on-demand, and if yes, step S1304 is performed; if no, step S1305 is performed.

S1304. The terminal device receives the Msg2 and the on-demand SIB at the next time point.

S1305. The terminal device receives Msg2 at the next time point.

S1306: The terminal device determines whether the next time point is in the time domain corresponding to the SIB of the on-demand, and if yes, executes step S1307; if not, returns to step S1302.

S1307. The terminal device receives the on-demand SIB.

After step S1307 is performed, the process returns to step S1302.

After step S1304 or S1305, the following steps S1308-S1317 are further included.

S1308: The terminal device determines whether the desired Msg2 is received. If yes, step S1311 is performed; if no, step S1309 is performed.

S1309: The terminal device determines whether the reception time window corresponding to Msg2 is completed. If yes, step S1310 is performed; if no, return to step S1302.

S1310: The terminal device determines whether the number of attempts to access reaches the threshold number of attempts, and if yes, ends the process; if not, returns to step S1301.

S1311: The terminal device sends Msg3 to the network device, where the Msg3 includes an identifier of at least one system message block (SIB) that the terminal device orders.

S1312: The next time point arrives, the terminal device determines whether the next time point is in the time domain corresponding to Msg4, and if yes, performs step S1313; if not, step 1316 is performed.

Here, the time point refers to a unit in the time domain, which can be specifically characterized as a time domain unit such as a frame, a time slot, and a symbol during a communication transmission.

S1313: The terminal device determines whether the next time point is in a time domain corresponding to the SIB of the on-demand, and if yes, step S1314 is performed; if no, step S1315 is performed.

S1314. The terminal device receives the Msg4 and the on-demand SIB at the next time point.

S1315. The terminal device receives the Msg4 at the next time point.

S1316. The terminal device determines whether the next time point is in the time domain corresponding to the SIB of the on-demand, and if yes, step S1317 is performed; if no, the process returns to step S1312.

S1317. The terminal device receives the on-demand SIB.

After step S1317 is performed, the process returns to step S1312.

After step S1314 or S1315, the following steps S1318-S1321 are further included.

S1318: The terminal device determines whether the desired Msg4 is received. If yes, the random access procedure ends, step S1319 is performed; if not, step S1321 is performed.

S1319: The terminal device determines whether all the SIBs in the on-demand SIB are received. If yes, the process ends; if not, step S1320 is performed.

S1320: The terminal device receives the unreceived SIB in a time domain corresponding to the SIB that is not received.

S1321. The terminal device determines whether the reception time window corresponding to Msg4 is completed. If yes, step S1310 is performed; if no, return to step S1312.

It should be noted that, in this embodiment, the terminal device first determines whether the time point is in the time domain corresponding to Msg4, and then determines whether the time point is in the time domain corresponding to the on-demand SIB. In an actual application, the terminal device may first determine whether the next time point is in the time domain corresponding to the on-demand SIB, and then determine whether the time point is in the time domain corresponding to Msg4.

It should be noted that the foregoing embodiments are all examples of the application of the Msg1 to Msg4 in the random access process, and in other implementations, the reference is made in the embodiment of the present application. The on-demand request and the confirmation information may also be carried in other newly defined messages, which are not limited in this embodiment of the present application.

By implementing the embodiment of the present application, after the terminal device initiates the request for the on-demand SIB, the downlink control information for indicating the time-frequency resource corresponding to the SIB of the on-demand and the downlink control for indicating the time-frequency resource corresponding to the acknowledgement information may be acquired in parallel. The information is that the terminal device does not need to wait for the acknowledgment information of the replies of the network device to obtain the downlink control information of the time-frequency resource corresponding to the SIB indicating the on-demand. Compared with the prior art, the terminal device may receive the on-demand SIB in advance, and shorten the receiving delay of the on-demand SIB.

Referring to FIG. 14, a structural block diagram of a terminal device provided by an embodiment of the present application is shown. The terminal device may be the terminal device described in the foregoing method embodiment, may send an on-demand request to the network device, and may receive the SIB sent by the network device.

As shown in FIG. 14, the terminal device 1400 may include: a transmitting unit 1401 and a first acquiring unit 1402. among them:

The sending unit 1401 is configured to send an on-demand request to the network device, where the on-demand request includes an identifier of the at least one system message block SIB that is requested by the terminal device.

The first obtaining unit 1402 is configured to acquire, in the at least one first time period, downlink control information that is used by the network device to indicate a time-frequency resource corresponding to the first SIB in the at least one SIB, where the first time period is The starting time point is earlier than or equal to the time point at which the terminal device receives the confirmation information that the network device replies to the on-demand request.

Optionally, the terminal device 1400 further includes: a first receiving unit 1403, configured to acquire, in the at least one first time period, the first sending unit 1402, in the at least one first time period, to indicate, in the at least one SIB After the downlink control information of the time-frequency resource corresponding to the SIB, the first SIB is received on the time-frequency resource corresponding to the first SIB.

Optionally, the start time point of the second time period indicated by the time-frequency resource corresponding to the first SIB is earlier than or equal to the time when the terminal device receives the acknowledgement information that the network device responds to the on-demand request reply point.

Optionally, the terminal device 1400 further includes: a second obtaining unit 1404, configured to acquire, in the at least one first time period, the first acquiring unit 1402, in the at least one first time period, for indicating the at least one SIB After the downlink control information of the time-frequency resource corresponding to the SIB, the downlink control information that is sent by the network device to indicate the time-frequency resource corresponding to the second SIB in the at least one SIB is acquired in the at least one third time period, where The starting time point of the third time period is later than the time point when the terminal device receives the confirmation information that the network device replies to the on-demand request.

Optionally, the terminal device 1400 further includes: a second receiving unit 1405, configured to acquire, in the at least one third time period, the second sending unit 1404, in the at least one third time period, for indicating the at least one SIB After the downlink control information of the time-frequency resource corresponding to the second SIB, the second SIB is received on the time-frequency resource corresponding to the second SIB.

Optionally, the first obtaining unit 1402 is specifically configured to:

Obscuring a physical downlink control channel PDCCH by using an identifier corresponding to the system message, and acquiring, from the PDCCH, a time-frequency resource that is sent by the network device to indicate that the first SIB in the at least one SIB is corresponding to the at least one first time period. Downstream control information.

Optionally, the on-demand request is carried in the first message Msg1, and the acknowledgement information is carried in the second message Msg2.

Optionally, the on-demand request is carried in the third message Msg3, and the acknowledgement information is carried in the fourth message Msg4.

It can be understood that the specific implementation of each functional unit included in the terminal device 1400 can refer to related functions of the terminal device in the method embodiments shown in FIG. 8, 9, 10, 11, 12, and 13, and details are not described herein again.

In the above embodiments, it may be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented in software, it may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer or processor, such as the previous processor 404, the processes or functions described in accordance with embodiments of the present invention are generated in whole or in part. The computer can be a general purpose computer, a special purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer readable storage medium or transferred from one computer readable storage medium to another computer readable storage medium, for example, the computer instructions can be from a website site, computer, server or data center Transmission to another website site, computer, server, or data center by wire (eg, coaxial cable, fiber optic, Digital Subscriber Line (DSL)) or wireless (eg, infrared, wireless, microwave, etc.). The computer readable storage medium can be any available media that can be accessed by a computer or a data storage device such as a server, data center, or the like that includes one or more available media. The usable medium may be a magnetic medium, such as a floppy disk, a hard disk, a magnetic tape, an optical medium such as a DVD, or a semiconductor medium such as a Solid State Disk (SSD).

One of ordinary skill in the art can understand all or part of the process of implementing the above embodiments, which can be completed by a computer program to instruct related hardware, the program can be stored in a computer readable storage medium, when the program is executed The flow of the method embodiments as described above may be included. The foregoing storage medium includes: a read-only memory (ROM) or a random access memory (RAM), a magnetic disk or an optical disk, and the like, which can store various program codes.

Claims (17)

1. A system message receiving method, comprising:

   The terminal device sends an on-demand request to the network device, where the on-demand request includes an identifier of at least one system message block SIB that is requested by the terminal device;

   And acquiring, by the network device, downlink control information, which is used by the network device, to indicate time-frequency resources corresponding to the first SIB in the at least one SIB, and the start time of each first time period, in the at least one first time period. The point is earlier than or equal to the time point at which the terminal device receives the confirmation information that the network device replies to the on-demand request.
2. The method according to claim 1, wherein the terminal device acquires, in the at least one first time period, a downlink that is sent by the network device to indicate a time-frequency resource corresponding to the first SIB in the at least one SIB. After the control information, it also includes:

   The terminal device receives the first SIB on a time-frequency resource corresponding to the first SIB.
3. The method according to claim 2, wherein a start time point of the second time period indicated by the time-frequency resource corresponding to the first SIB is earlier than or equal to that the terminal device receives the network device for The point in time at which the confirmation information of the request for reply is requested.
4. The method according to any one of claims 1 to 3, wherein the terminal device acquires, by using the network device, the first SIB corresponding to the at least one SIB, corresponding to the at least one first time period. After the downlink control information of the time-frequency resource, the method further includes:

   And obtaining, by the network device, downlink control information, which is used by the network device, to indicate time-frequency resources corresponding to the second SIB in the at least one SIB, and the start time of each third time period, in the at least one third time period. A point in time when the terminal device receives the confirmation information that the network device replies to the on-demand request.
5. The method according to claim 4, wherein the terminal device acquires, in the at least one third time period, a downlink that is sent by the network device to indicate a time-frequency resource corresponding to the second SIB in the at least one SIB. After the control information, it also includes:

   The terminal device receives the second SIB on a time-frequency resource corresponding to the second SIB.
6. The method according to any one of claims 1 to 5, wherein the terminal device acquires, by using the network device, the first SIB corresponding to the at least one SIB, corresponding to the at least one first time period. Downlink control information of time-frequency resources, including:

   The terminal device descrambles the physical downlink control channel PDCCH by using the identifier corresponding to the system message in the at least one first time period, and acquires, from the PDCCH, the first SIB corresponding to the at least one SIB sent by the network device. Downlink control information of time-frequency resources.
7. The method according to any one of claims 1 to 6, wherein the on-demand request is carried in the first message Msg1, and the confirmation information is carried in the second message Msg2.
8. The method according to any one of claims 1 to 7, wherein the on-demand request is carried in a third message Msg3, and the confirmation information is carried in the fourth message Msg4.
9. A terminal device, comprising: a sending unit and a first acquiring unit, wherein:

   The sending unit is configured to send an on-demand request to the network device, where the on-demand request includes an identifier of the at least one system message block SIB that is requested by the terminal device;

   The first acquiring unit is configured to acquire, in the at least one first time period, downlink control information that is used by the network device to indicate a time-frequency resource corresponding to the first SIB in the at least one SIB, where the first time is The start time point of the segment is earlier than or equal to the time point at which the terminal device receives the acknowledgement information that the network device replies to the on-demand request.
10. The terminal device according to claim 9, wherein the terminal device further comprises:

    a first receiving unit, configured to: after the first acquiring unit acquires downlink control information that is used by the network device to indicate a time-frequency resource corresponding to the first SIB in the at least one SIB, in the at least one first time period, Receiving the first SIB on a time-frequency resource corresponding to the first SIB.
11. The terminal device according to claim 10, wherein a start time point of the second time period indicated by the time-frequency resource corresponding to the first SIB is earlier than or equal to that the terminal device receives the network device for The point in time at which the confirmation information of the request for reply is requested.
12. The terminal device according to any one of claims 9 to 11, wherein the terminal device further comprises:

    a second acquiring unit, configured to: after the first acquiring unit acquires downlink control information that is used by the network device to indicate time-frequency resources corresponding to the first SIB in the at least one SIB, in the at least one first time period, Obtaining, in the at least one third time period, downlink control information that is sent by the network device to indicate a time-frequency resource corresponding to the second SIB in the at least one SIB, where a starting time point of each third time period is later than And a time point at which the terminal device receives the confirmation information that the network device responds to the on-demand request.
13. The terminal device according to claim 12, wherein the terminal device further comprises:

    a second receiving unit, configured to: after the second acquiring unit acquires downlink control information that is sent by the network device to indicate a time-frequency resource corresponding to the second SIB in the at least one SIB, in the at least one third time period And receiving, by the second SIB, on the time-frequency resource corresponding to the second SIB.
14. The terminal device according to any one of claims 9 to 13, wherein the first obtaining unit is specifically configured to:

    Obscuring a physical downlink control channel PDCCH by using an identifier corresponding to the system message, and acquiring, from the PDCCH, a time-frequency resource that is sent by the network device to indicate that the first SIB in the at least one SIB is corresponding to the at least one first time period. Downstream control information.
15. The terminal device according to any one of claims 9 to 14, wherein the on-demand request is carried in the first message Msg1, and the confirmation information is carried in the second message Msg2.
16. The terminal device according to any one of claims 9 to 15, wherein the on-demand request is carried in the third message Msg3, and the confirmation information is carried in the fourth message Msg4.
17. A terminal device, comprising a processor, a memory, a transmitter, and a receiver, the memory for storing data and/or program code, the processor for invoking data and/or program stored by the memory The code executes the system message receiving method according to any one of claims 1 to 8.

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