An initial access method and apparatus

Abstract

Embodiments of the present application provide a method and device for initial access. The method introduces space division multiplexing SSB, and simultaneously transmits multiple SSB beams on the same time-frequency resource, thereby reducing the time domain overhead of SSB while not reducing the resolution of SSB beams.

Description

Technical Field

[0001] This application relates to the field of wireless communication, and more particularly to an initial access method and apparatus. Background Technology

[0002] In cellular communication systems, even if a cell does not establish a radio connection with any user equipment (UE) and does not require data transmission, the base station managing the cell still needs to transmit some public signals. These public signals are mainly used by the UE for cell search, initial access, and mobility-related measurements. In fifth-generation (5G) cellular communication systems... th In the New Radio (NR) system of 5G mobile communication systems, these common signals include the primary synchronization signal (PSS), secondary synchronization signal (SSS), physical broadcast channel (PBCH), multicast channels carrying system information (SI), and multicast channels carrying paging messages. The PSS, SSS, and PBCH together are called the synchronization signal and PBCH block (SSB). SSB transmission is periodic and requires beam scanning to ensure all UEs within the cell can receive the SSB. Similarly, the multicast channels carrying SI and paging messages also need to be transmitted periodically and undergo beam scanning. These downlink common signals have a large time domain presence. For example, in a network deployment scenario in the millimeter-wave band of frequency range 2 (FR2), corresponding to a frequency range of 24250MHz–52600MHz, the SSB has as many as 64 beams, with a symbol ratio as high as 15%. These limitations prevent base station transmission links from undergoing a higher proportion of time-domain shutdown and sleep mode, resulting in significant energy consumption even when the base station is not in use. Summary of the Invention

[0003] This application provides an initial access method and communication device to reduce the time-domain resource overhead of SSB.

[0004] In a first aspect, an embodiment of the present application provides an initial access method, which comprises: a base station sending M first common channels to a UE, wherein the first common channels comprise synchronization signals and physical broadcast channels, the physical broadcast channels carrying part MSI of a cell, the part MSI indicating a transmission configuration of RMSI of the cell, and time-frequency resources of the M first common channels being completely identical; the UE detecting the M first common channels and determining a target first common channel; the base station sending M second common channels corresponding to the M first common channels to the UE, and the spatial domain filtering parameters used for sending the M second common channels being identical to the spatial domain filtering parameters used for sending the M first common channels; the UE receiving a target second common channel corresponding to the target first common channel using a target spatial domain filtering parameter, the target second common channel carrying the RMSI, and the target spatial domain filtering parameter being the spatial domain filtering parameter used for receiving the target first common channel; the UE sending a target PRACH using the target spatial domain filtering parameter; and the base station receiving M groups of physical random access channels (PRACHs) corresponding to the M first common channels, and the spatial domain filtering parameter used for receiving the mth group of PRACHs in the M groups of PRACHs being identical to the spatial domain filtering parameter used for sending the mth first common channel in the M first common channels, M being an integer greater than 1, and m being a positive integer less than or equal to M.

[0005] The method introduces spatial division multiplexing SSB transmission, and simultaneously transmits multiple SSB beams on the same time-frequency resource, so as to reduce the time domain overhead of SSB while not reducing the resolution of SSB beams.

[0006] In a possible implementation, the first information of the first common channel indicates a first index, and different first common channels in the M first common channels indicate different values of the first index.

[0007] In a possible implementation, the UE determines a target first index corresponding to the target first common channel according to the first information of the target first common channel, and different first common channels in the M first common channels indicate different values of the first index.

[0008] Through the above implementation, the base station can indicate different SSBs in the M SSBs through the first information, so that the UE knows which SSB in the M SSBs is detected.

[0009] In a possible implementation, the first information is at least one of the following: DMRS-related information of the first common channel; an index field in the first common channel; and a parameter in a channel coding, modulation, or scrambling process of the first common channel.

[0010] In a possible implementation, the DMRS-related information is one of the following: a sequence index of the DMRS; an initialization identification value of the DMRS sequence; an index of a resource element position of the DMRS; or an index of an orthogonal cover code of the DMRS.

[0011] In a possible implementation, the index field indicates a target first common channel of the M first common channels.

[0012] In a possible implementation, the parameter in the channel coding, modulation, or scrambling process of the first common channel is an index of a scrambling sequence of the first common channel or an initialization value of the scrambling sequence of the first common channel.

[0013] In a possible implementation, the frequency domain resource of the first common channel is 20*M RBs.

[0014] In a possible implementation, the time-frequency resources of the M second common channels are the same. By introducing the second common channels with spatial division multiplexing, the transmission efficiency of the second common channels can be improved.

[0015] In a possible implementation, each of the M groups of PRACHs contains L PRACHs, and the time-frequency resource of the kth PRACH of each of the M groups of PRACHs is the same, where L is a positive integer, and k is a positive integer less than or equal to L.

[0016] In a possible implementation, the base station transmits M groups of paging channels corresponding to the M first common channels one by one, and the spatial domain filtering parameter used by the mth group of paging channels of the M groups of paging channels is the same as the spatial domain filtering parameter used by the mth first common channel of the M first common channels, where m is a positive integer less than or equal to M. Each of the M groups of paging channels contains at most S paging channels.

[0017] In a possible implementation, the UE receives the target paging channel using the target spatial domain filtering parameter.

[0018] In a possible implementation, the M first common channels correspond to the M groups of paging channels one by one, and a group of paging channels corresponding to the target first common channel contains the target paging channel. Each of the M groups of paging channels contains S paging channels, and the time-frequency resource of the s th paging channel of each of the M groups of paging channels is the same, where s is a positive integer less than or equal to S.

[0019] By the above implementation, the spatial division multiplexing of the paging channels is introduced, and the transmission efficiency of the paging channels can be improved.

[0020] In a second aspect, an embodiment of the present application provides a communication apparatus, which can be a terminal, and can also be a chip for a terminal. The apparatus has the function of the UE in any of the implementation manners of the first aspect. The function can be implemented by hardware, or by hardware executing corresponding software. The hardware or software includes one or more modules corresponding to the above functions.

[0021] In a third aspect, an embodiment of the present application provides a communication apparatus, which can be a network device, and can also be a chip for a network device. The apparatus has the function of the base station in any of the implementation manners of the first aspect. The function can be implemented by hardware, or by hardware executing corresponding software. The hardware or software includes one or more modules corresponding to the above functions.

[0022] In a fourth aspect, an embodiment of the present application provides a communication apparatus, including a processor and a memory; the memory is used to store computer instructions, when the apparatus is running, the processor executes the computer instructions stored in the memory, so that the apparatus executes the method in any of the implementation manners of the first aspect.

[0023] In a fifth aspect, an embodiment of the present application provides a communication apparatus, including a processor and an interface circuit, the processor is used to communicate with other apparatuses through the interface circuit, and execute the method in any of the implementation manners of the first aspect. The processor includes one or more.

[0024] In a sixth aspect, an embodiment of the present application further provides a computer readable storage medium, the computer readable storage medium has instructions stored therein, when the instructions are running on a communication apparatus, the instructions cause the communication apparatus to execute the method in any of the implementation manners of the first aspect.

[0025] In a seventh aspect, an embodiment of the present application further provides a computer program product, the computer program product includes a computer program, when the computer program is running on a communication apparatus, the computer program causes the communication apparatus to execute the method in any of the implementation manners of the first aspect.

[0026] In an eighth aspect, an embodiment of the present application further provides a chip system, including: a processor, used to execute the method in any of the implementation manners of the first aspect. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 The architecture schematic diagram of a mobile communication system provided for an embodiment of the present application is shown in the figure;

[0028] Figure 2 The time-frequency structure schematic diagram of an SSB provided for an embodiment of the present application is shown in the figure;

[0029] Figure 3A schematic diagram of 4 digital channels forming 4 time division multiplexed beams for embodiments of the application;

[0030] Figure 4 A schematic diagram of a base station implementing 4 spatial division multiplexed beams through 4 digital channels for embodiments of the application;

[0031] Figure 5 A flow chart of an initial access method for embodiments of the application;

[0032] Figure 6 A schematic diagram of a communication device for embodiments of the application;

[0033] Figure 7 A schematic diagram of another communication device for embodiments of the application. DETAILED DESCRIPTION

[0034] Figure 1 A schematic diagram of an architecture of a communication system 1000 to which embodiments of the application can be applied. As shown in the Figure 1 , the communication system includes a radio access network 100 and a core network 200. Optionally, the communication system 1000 can further include an Internet 300. The radio access network 100 can include at least one radio access network device (e.g., 110a and 110b in Figure 1 ), and can further include at least one terminal (e.g., 120a-120j in Figure 1 ). The terminal is connected to the radio access network device in a wireless manner, and the radio access network device is connected to the core network in a wireless or wired manner. The core network device and the radio access network device can be independent and different physical devices, can be integrated into the same physical device with the functions of the core network device and the logical functions of the radio access network device, or can be a physical device integrated with part of the functions of the core network device and part of the functions of the radio access network device. The terminals can be connected to each other and the radio access network devices can be connected to each other in a wired or wireless manner. Figure 1 This is only a schematic diagram, and the communication system can further include other network devices, such as wireless relay devices and wireless backhaul devices, which are not shown in Figure 1 .

[0035] The radio access network device can be a base station, an evolved NodeB (eNodeB), a transmission reception point (TRP), a next generation NodeB (gNB) in a 5th generation (5G) mobile communication system, a next generation NodeB in a 6th generation (6G) mobile communication system, a base station in a future mobile communication system, or an access node in a WiFi system, etc. The radio access network device can also be a module or unit that performs part of the functions of a base station, for example, it can be a central unit (CU) or a distributed unit (DU). The CU performs the functions of the radio resource control protocol and the packet data convergence protocol (PDCP) of the base station, and can also perform the function of the service data adaptation protocol (SDAP). The DU performs the functions of the radio link control layer and the medium access control (MAC) layer of the base station, and can also perform part or all of the functions of the physical layer. For specific descriptions of the above-mentioned protocol layers, reference can be made to the relevant technical specifications of the 3rd generation partnership project (3GPP). The radio access network device can be a macro base station (such as 110a in FIG. 1), a micro base station or an indoor station (such as 110b in FIG. 1), a relay node or a donor node, etc. The embodiments of the present application do not limit the specific technology and specific device form adopted by the radio access network device. For ease of description, the following describes the base station as an example of the radio access network device. Figure 1 Figure 1

[0036] ​​A terminal can also be called a terminal device, UE, mobile station, mobile terminal, etc. Terminals can be widely used in various scenarios, such as device-to-device (D2D), vehicle-to-everything (V2X) communication, machine-type communication (MTC), Internet of Things (IoT), virtual reality, augmented reality, industrial control, autonomous driving, telemedicine, smart grids, smart furniture, smart offices, smart wearables, smart transportation, smart cities, etc. Terminals can be mobile phones, tablets, computers with wireless transceiver capabilities, wearable devices, vehicles, drones, helicopters, airplanes, ships, robots, robotic arms, smart home devices, etc. The embodiments of this application do not limit the specific technologies or device forms used in the terminals.

[0037] Base stations and terminals can be fixed or mobile. They can be deployed on land, including indoors or outdoors, handheld or vehicle-mounted; they can also be deployed on water; and they can be deployed on aircraft, balloons, and satellites. The embodiments of this application do not limit the application scenarios of the base stations and terminals.

[0038] The roles of base stations and terminals can be relative, for example, Figure 1 The helicopter or drone 120i can be configured as a mobile base station. For terminals 120j accessing the wireless access network 100 via 120i, terminal 120i is a base station; however, for base station 110a, 120i is a terminal, meaning that 110a and 120i communicate via a wireless air interface protocol. Of course, 110a and 120i can also communicate via a base station-to-base station interface protocol; in this case, 120i is also a base station relative to 110a. Therefore, both base stations and terminals can be collectively referred to as communication devices. Figure 1 The 110a and 110b in the text can be referred to as communication devices with base station functions. Figure 1 The 120a-120j in the text can be referred to as communication devices with terminal functions.

[0039] Communication between base stations and terminals, between base stations, and between terminals can be conducted using licensed spectrum, unlicensed spectrum, or both simultaneously. Communication can be conducted using spectrum below 6 GHz, spectrum above 6 GHz, or both simultaneously. The embodiments of this application do not limit the spectrum resources used for wireless communication.

[0040] In the embodiments of the present application, the functions of the base station can also be performed by a module (such as a chip) in the base station, or by a control subsystem containing the functions of the base station. The control subsystem containing the functions of the base station herein can be a control center in the above-mentioned application scenarios such as smart grids, industrial control, intelligent transportation, and smart cities. The functions of the terminal can also be performed by a module (such as a chip or a modem) in the terminal, or by a device containing the functions of the terminal.

[0041] In the embodiments of the present application, the base station sends a downlink signal or downlink information to the terminal, and the downlink information is carried on a downlink channel; the terminal sends an uplink signal or uplink information to the base station, and the uplink information is carried on an uplink channel. In order to communicate with the base station, the terminal needs to establish a wireless connection with a cell controlled by the base station. The cell with which the terminal establishes a wireless connection is called a serving cell of the terminal. When the terminal communicates with the serving cell, it will also be interfered by signals from neighboring cells.

[0042] In the embodiments of the present application, the transmission of a signal or information can include the sending action of the sending end and the receiving action of the receiving end.

[0043] In the embodiments of the present application, the time domain symbol can be an orthogonal frequency division multiplexing (OFDM) symbol, or a Discrete Fourier Transform-spread-OFDM (DFT-s-OFDM) symbol. If not specified, the symbol in the embodiments of the present application refers to a time domain symbol.

[0044] It can be understood that, in the embodiments of the present application, the physical downlink shared channel (PDSCH), the physical downlink control channel (PDCCH), the physical uplink shared channel (PUSCH), and the PBCH are only examples of the downlink data channel, the downlink control channel, the uplink data channel, and the broadcast channel of the physical layer, respectively. In different systems and different scenarios, these channels can have different names, and the embodiments of the present application do not limit this. The sending channel A can also be understood as sending information through the channel A; the receiving channel B can also be understood as receiving information through the channel B.

[0045] Before introducing the embodiments of the present application, the process of UE initial access to a cell in the NR system is introduced. The process of UE from idle state access to a cell to become connected state mainly includes the following links: SSB detection, system information block 1 (SIB1) reception, paging and random access (RA).

[0046] (1) SSB detection

[0047] The UE can obtain the identity of the cell, complete downlink timing synchronization and obtain the master information block (MIB) through the detection of the SSB, wherein the MIB includes the configuration parameters of the PDCCH used for scheduling the SIB1. The PSS and SSS can carry the physical cell identifier (PCI), and the UE obtains the PCI through the detection of the PSS and SSS. The MIB is carried in the PBCH of the SSB, and the PBCH also indicates the SSB index. Each SSB index corresponds to a transmission position. The UE completes the downlink timing synchronization through the detected SSB index and the detection time.

[0048] The UE can also complete the transmission beam training of the base station side through the detection of the SSB. Since the beam for transmitting the SSB is wider than the beam used for communication after the RRC connection is established with the UE, the transmission beam of the SSB can also be called a wide beam. In the NR, the transmission of the SSB follows a SSB pattern, and the SSB pattern includes at least one SSB. Different SSBs in the SSB pattern correspond to different SSB indexes, and different SSB indexes correspond to different time-frequency positions, that is, they can correspond to different time domain positions and the same frequency domain position, or different frequency domain positions and the same time domain position, or different time domain positions and different frequency domain positions. Alternatively, different SSB indexes correspond to different base station end transmission space filtering parameters, or different transmission beams. The SSB index can be carried in the PBCH of the SSB. The UE can select the SSB with the strongest received signal and determine the corresponding SSB index through the detection of the SSB, thereby completing the training of the UE to the transmission beam of the base station.

[0049] Optionally, the UE can also receive the same SSB index in multiple SSB patterns with different receive beams, so as to determine the optimal receive beam at the UE side and complete the UE-side receive beam training. The functions of the base station wide beam include: 1) the UE receives the SIB1 and paging message (referred to as SIB1 / Paging) sent using the same beam at the time-frequency position corresponding to the SSB index, improving the coverage of SIB1 / Paging; 2) the UE sends a physical random access channel (PRACH) at the position corresponding to the SSB index, and the base station can receive the PRACH using the wide beam corresponding to the SSB index, improving the PRACH reception success probability; 3) after the UE completes the initial access to establish an RRC connection, the base station can perform narrow beam training based on the wide beam, that is, only the narrow beams within the range of the wide beam are trained, reducing the narrow beam training overhead.

[0050] The time-frequency structure of an SSB is shown in FIG. 1. Figure 2 One SSB occupies 4 consecutive symbols in the time domain and 20 resource blocks (RBs), i.e., 240 subcarriers, in the frequency domain.

[0051] In the embodiments of the present application, the spatial domain filtering parameter can be a receiving-end spatial domain filtering parameter, including a combining matrix or processing matrix used for receiving signals on multiple receiving antennas or receiving channels of the receiving end, specifically, for example, an equalization matrix or combining matrix in the digital domain, a receiving beam in the analog domain, etc.; or a transmitting-end spatial domain filtering parameter, including a beam-forming matrix or processing matrix used for transmitting signals on multiple transmitting antennas or transmitting channels of the transmitting end, specifically, for example, a precoding matrix or beam-forming matrix in the digital domain, a transmitting beam in the analog domain, etc. The spatial domain filtering parameters are the same, which can also mean that the spatial domain filtering parameter used when transmitting the signal A is the same as the spatial domain filtering parameter used when receiving the signal B. The receiving beam and the transmitting beam are sometimes also referred to as a beam. In the present application, for the sake of brevity, the spatial domain filtering parameter is described by taking the beam as an example.

[0052] (2) SIB1 reception

[0053] Through the above SSB detection, the UE acquires the MIB. The MIB indicates the candidate time-frequency location of the PDCCH used to receive the scheduling SIB1. The UE blindly detects the PDCCH at the candidate time-frequency location, and if the PDCCH is detected, the UE can receive the PDSCH according to the specified manner at the time-frequency resource indicated by the downlink control information (DCI) in the PDCCH, thereby acquiring the SIB1 carried in the PDSCH. The SIB1 contains a lot of information, but the most important function is to complete the configuration of the primary cell (PCell), so that the UE in the idle state can listen to the paging message, or complete the uplink timing synchronization through random access, so that the UE transits to the connected state.

[0054] One SSB index is associated with one SIB1 occasion. For example, SSB index #1 is associated with SIB1 occasion #1, then the base station transmits SIB1 or transmits the PDCCH scheduling the SIB1 at SIB1 occasion #1, and the transmission beam used is the same as the transmission beam used by the base station to transmit SSB index #1; correspondingly, the UE receives SIB1 or receives / detects the PDCCH scheduling the SIB1 at SIB1 occasion #1, and the reception beam used is the same as the reception beam used to receive SSB index #1.

[0055] (3) Paging

[0056] Similar to SIB1, UE needs to monitor paging message when it is in idle state. Specifically, UE acquires the configuration information of paging message, including the configuration information of paging frame and paging occasion, after receiving SIB1. UE determines paging occasion, and further determines multiple monitoring occasions, or a monitoring occasion set. Each monitoring occasion is a DCI blind detection occasion. One SSB index is associated with a group of monitoring occasions in one monitoring occasion set, i.e. a monitoring occasion subset. Different SSB indexes are associated with different monitoring occasions. Assuming that SSB index #1 is associated with monitoring occasion subset #1, the transmitting beam of the base station when sending PDCCH scheduling the paging message on the monitoring occasion subset #1 is the same as the transmitting beam of the base station when sending SSB index #1. The receiving beam of the UE when receiving / detecting PDCCH scheduling the paging message on the monitoring occasion subset #1 is the same as the receiving beam of the UE when receiving SSB index #1.

[0057] (4) Random access

[0058] 4-step RA and 2-step RA are defined in NR. An example of 4-step RA is given below.

[0059] Step 1: UE sends PRACH to the base station, which is also called message 1 (Msg1).

[0060] The UE first selects one SSB with reference signal received power (RSRP) greater than a threshold configured by high layer signaling according to the RSRP of the SSB, determines the set of RACH occasions and preamble indexes that can be selected according to the association between the SSB and the random access channel (RACH), and transmits Msg1 according to the spatial filtering parameter used when the SSB is received. The association between the SSB and the RACH and the time domain resource and frequency domain resource of the PRACH are indicated by SIB1. The time domain resource of the PRACH is repeated in slots, and there is one or more RACH occasions in each slot.

[0061] Step 2: The base station sends a random access response (RAR) to the UE, and the RAR is also referred to as Msg2.

[0062] After the UE transmits Msg1, the UE detects the DCI scrambled by the random access-radio network temporary identifier (RNTI) in a specified time domain window. The value of the RA-RNTI is related to the time-frequency position of the PRACH transmitted by the UE, that is, the base station can implicitly tell the UE whether the DCI scrambled by the RA-RNTI is for the UE by using different values of the RA-RNTI. If the UE detects the DCI scrambled by the RA-RNTI corresponding to the UE, the UE receives the PDSCH scheduled by the DCI. The PDSCH carries a MAC protocol data unit (PDU) carrying multiple subPDUs. Each subPDU indicates a preamble index and includes a MAC RAR containing uplink scheduling information for the UE transmitting the preamble index.

[0063] The RAR has three functions: one is to send an initial uplink transmission timing advance (TA) to help the UE complete uplink timing synchronization; the second is to send a temporary cell-radio network temporary identifier (TC-RNTI); and the third is to send uplink scheduling information for scheduling PUSCH.

[0064] Step 3: The UE sends Msg3 to the base station.

[0065] UE sends Msg3 on PUSCH according to TA indicated by RAR. Data carried on PUSCH is scrambled by TC-RNTI at physical layer, and the data includes identifier (ID) of the UE.

[0066] Step 4: Base station sends Msg4 to UE.

[0067] After UE sends Msg3, it detects DCI scrambled by TC-RNTI in corresponding time window. If detection is successful, it receives corresponding PDSCH. The PDSCH contains a contention resolution identifier. If the identifier matches the ID of the UE, it means that the random access conflict resolution is successful. The UE changes TC-RNTI to C-RNTI. At this point, the RA process of the UE is completed.

[0068] Currently, the time domain width of one SSB is 4 symbols, and there are only 2 SSBs in one slot (containing 14 symbols), so there are 6 symbols idle for one slot containing 14 symbols. For high frequency deployment scenarios, such as the above-mentioned deployment in the FR2 frequency band, SSB is generally transmitted using a wide beam, while data is generally transmitted using a narrow beam. Therefore, the slot where the SSB is located cannot be used for data transmission. The time domain resource overhead of the slot level caused by SSB is as high as 25%. Even if the cell has no data transmission, SSB still needs to be transmitted to ensure basic public channel coverage, so that the base station cannot be continuously turned off, causing a lot of power consumption. For millimeter waves, due to the current device process constraints, the power consumption of the base station is mainly related to the duty cycle of the transmitted signal in the time domain (that is, the time domain overhead), and has little to do with the frequency domain resource size of the transmitted signal.

[0069] Obviously, the SSB coverage enhancement requirement and the low time domain overhead requirement of millimeter waves are contradictory: in order to enhance coverage, more and narrower beams must be used, and due to implementation constraints, different analog beams can only be transmitted on different time domain symbols, so the time domain overhead will inevitably increase, causing greater base station energy consumption.

[0070] A general millimeter wave base station has 4 or 8 digital channels, and each digital channel is associated with many analog channels / antenna arrays. For example, a base station with 8 digital channels will have 32 analog channels / antenna arrays. Figure 3As an example of four digital channels (TRX#1, TRX#2, TRX#3, TRX#4) in the figure, DAC represents an analog-to-digital conversion and digital-to-analog conversion module, PS represents a phase shifter, and PA represents a power amplifier. Assuming that the four digital channels are associated with a total of 2048 elements, and that each 2 elements are associated with an analog channel, there are 1024 analog channels, and each digital channel is associated with 256 analog channels. Under the existing time division multiplexing transmission scheme, the base station transmits one SSB beam, and all four digital channels and 1024 analog channels will participate in beamforming. The base station needs to transmit four different SSB beams, which are transmitted in four time domain positions (t1, t2, t3, and t4) in time division.

[0071] To solve the above-mentioned contradiction, the bandwidth of the SSB can be increased, the transmission power of the SSB can be increased (or the equivalent transmission code rate of the SSB can be reduced), and the coverage of the SSB can be increased. The corresponding SSB can also be referred to as a wideband SSB. In this way, the number of SSB beams that need to be transmitted in the time domain can be reduced, and the time domain overhead of the SSB can be reduced. For example, the current SSB occupies 20 RBs in the frequency domain, about 30 MHz. If the frequency domain width of the SSB is increased by 4 times, the coverage of a single SSB is increased by about 6 dB. Correspondingly, the beamforming gain requirement of the SSB can be reduced by 6 dB, that is, the beam width of the SSB can be increased by 4 times, the number of SSB beams can be reduced to 1 / 4 of the original, the symbol overhead can be reduced from 15% to 3.8%, and the time slot overhead can be reduced from 25% to 6.3%. Although the wideband SSB can reduce the time domain resource overhead of the SSB while ensuring that the coverage does not change substantially, this scheme causes the SSB beam to become wider, the SSB beam resolution to decrease, and further causes the congestion probability of the PRACH to increase.

[0072] As mentioned earlier, the PRACH transmission and the SSB are associated. If the SSB beam becomes wider and the number of SSB beams is reduced, one possible implementation is that the base station receives the PRACH beam also becomes wider, and increases the PRACH transmission bandwidth or transmission time to improve coverage. For a UE at the edge of a cell, the power is often limited. At this time, increasing the bandwidth cannot increase the power, so the coverage of the PRACH cannot be improved, thereby causing the access success rate of the UE to decrease. If the PRACH transmission time is increased, the UE needs to occupy more resources to transmit the PRACH, which not only increases the power consumption of the UE, but more importantly, increases the congestion probability of the PRACH transmission, which also reduces the access success rate of the UE.

[0073] Based on the transmission scheme of wideband SSB, another possible embodiment is proposed in the present application, which is the SSB transmission method of space division multiplexing (SDM), i.e., multiple SSB beams are transmitted simultaneously on the same time-frequency resource, so as to reduce the time domain overhead of SSB without reducing the resolution of SSB beam, and further reduce the power consumption of the base station.

[0074] The core of the present embodiment is to enable the SDM transmission of SSB. In order to realize the embodiment, a possible implementation architecture is that the base station supports multiple digital channels, each digital channel forms an SSB beam by using its associated analog channel and array, and multiple digital channels can form multiple SSB beams. Figure 4 is a possible base station implementation architecture provided by the present embodiment, which takes four digital channels to form four beams as an example.

[0075] Figure 5 is a flowchart of an initial access method provided by the present embodiment.

[0076] S510, the base station transmits M first common channels, M is an integer greater than 1.

[0077] The first common channel is a synchronization signal, or the first common channel includes a synchronization signal and a physical broadcast channel. The synchronization signal can carry a physical cell identifier, and the physical broadcast channel can carry part of the minimum system information (MSI) of the cell. The part of the MSI indicates the transmission configuration of the remaining minimum system information (RMSI) of the cell. The cell is a cell managed by the base station. The transmission configuration of the RMSI indicated by the part of the MSI can be the transmission configuration of the DCI scheduling the RMSI, for example, the part of the MSI indicates the time-frequency resource for scheduling the DCI of the RMSI. The part of the MSI carried by the above broadcast channel can also be called MIB, and the RMSI can also be called SIB1.

[0078] Without loss of generality, the first common channel is taken as an example to be described below.

[0079] Optionally, the base station transmits M SSBs through M different beams. The M beams correspond to the M SSBs one by one, that is, the base station transmits different SSBs in the M SSBs through different beams in the M beams. The first information in the SSB indicates a first index, wherein the different SSBs in the M SSBs indicate different values of the first index. The M first indexes correspond to the M beams one by one, or in other words, the values of the different first indexes in the M first indexes indicate different beams in the M beams. The above-mentioned M SSBs are transmitted on one SSB occasion, and the SSB occasion is one of N SSB occasions, and the N SSB occasions correspond to N time-frequency positions that are completely non-overlapping, for example, N time-domain positions that are completely non-overlapping, and N is an integer greater than 1.

[0080] Optionally, one SSB occasion corresponds to one time-frequency position for transmitting an SSB, and the time-frequency resources of the M SSBs transmitted on one SSB occasion are completely the same. Alternatively, the time-frequency resources of the M SSBs transmitted on one SSB occasion partially overlap, for example, the time-domain positions of the M SSBs are the same, and the frequency-domain positions partially overlap.

[0081] Optionally, the base station transmits SSBs according to a predefined SSB pattern. The predefined SSB pattern can include the time-frequency positions of N SSB occasions in the pattern and the number M of SSBs transmitted in each SSB occasion. The time-frequency positions of the N SSB occasions can be relative positions relative to a certain predefined SSB occasion, such as relative positions relative to SSB occasion #0 with the smallest index value in the N SSB occasions. The SSB pattern can be predefined by a protocol.

[0082] The N*M SSBs in the N SSB occasions included in the SSB pattern can be numbered uniformly. The N SSB occasions are numbered #0 to #(N-1), and the M SSBs in SSB occasion #n are numbered #M*n to #(M*n+M-1), that is, the value range of the first index is M*n to (M*n+M-1). At this time, the first index can also be referred to as SSB index.

[0083] The N*M SSBs included in the N SSB occasions in the SSB pattern can also be numbered in two levels. The first index is the number of the M SSBs in a certain SSB occasion, and the value range is 0~(M-1); the second index is the number of a certain SSB occasion in the N SSB occasions, and the value range is 0~(N-1). The first index can also be referred to as a beam index, the second index can also be referred to as an SSB occasion index, and the combination of the first index and the second index can be referred to as an SSB index.

[0084] Optionally, the base station transmits the corresponding M SSBs using at least M digital channels in 1 SSB occasion. That is, at least one digital channel is responsible for the digital signal processing of one SSB. Different SSBs are processed by different digital channels. Alternatively, different SSBs are associated with the same digital channel, but different mapping matrices are used. One possible implementation is that the base station uses M digital channels, and each digital channel is associated with an analog channel and an element to form an SSB beam, and each beam is used to transmit one SSB.

[0085] Optionally, the frequency domain resource of the first common channel is 20*M RBs.

[0086] S511, the UE detects the M SSBs to determine a target SSB.

[0087] The UE detects the SSBs on the N SSB occasions, specifically, detects the M SSBs on each SSB occasion. Optionally, for a certain potential SSB occasion, the UE determines the first index corresponding to the detected SSB through detection or decoding of the SSB, so as to know which beam the SSB corresponds to.

[0088] The UE can determine the value of the first index through the first information of the target SSB. The first information can be one of the following four cases.

[0089] (1) Demodulation reference signal (DMRS) related information of the PBCH. Specifically, the first information can be a sequence index of the DMRS or an initialization identification value of the DMRS sequence, that is, different first indexes correspond to different DMRS sequences or different DMRS sequence initialization identification values. Alternatively, the first information is an index of a resource element (RE) position of the DMRS or an index of an orthogonal cover code (OCC) of the DMRS, that is, different first indexes correspond to different RE position indexes of the DMRS or different OCC indexes of the DMRS. In this application, the DMRS of the PBCH can also be referred to as the DMRS of the SSB.

[0090] In this case, the UE needs to perform at least M times of DMRS blind detection on each SSB occasion, corresponding to the above-mentioned M first information values, such as using M sequences, using M RE positions, using M OCCs for DMRS detection, and the like.

[0091] (2) The first information can be a field A in the PBCH. Specifically, the field A can be an index field. The index field can indicate a target SSB in the M SSBs.

[0092] The index field can be decoupled from the SSB occasion index field and is an independent field, for example, the field has bits, indicating one SSB in the M SSBs on one SSB occasion, for example, indicating the target SSB. The index field can also be understood as indicating one transmission beam in the M SSB transmission beams, for example, indicating the target transmission beam. The index field can also be referred to as a beam index field. In this application, the symbol represents rounding up.

[0093] Alternatively, the index field can simultaneously indicate the SSB occasion index and the beam index within the SSB occasion, that is, the index field indicates the SSB index, for example, the index field has bits.

[0094] Alternatively, the field A in the PBCH indicates the beam index, and the field B in the PBCH indicates the SSB occasion index.

[0095] (3) The first information can be a certain parameter in the encoding, modulation or scrambling process of the PBCH. Specifically, the first information can be a certain encoding parameter of the PBCH, for example, the index of the scrambling matrix. Or, the first information can be a certain modulation parameter of the PBCH, for example, the modulation order or the constellation rotation angle. Or, the first information can be a certain scrambling parameter of the PBCH, for example, the scrambling sequence index of the PBCH or the initialization value of the scrambling sequence of the PBCH.

[0096] In this case, the UE needs to perform at least M times of PBCH reception on each SSB occasion, corresponding to the above-mentioned M values of the first information, such as using M scrambling matrices, M modulation orders or rotation angles, or M scrambling sequences for PBCH reception.

[0097] (4) The first information is a combination of at least two of the above-mentioned three kinds of information. Taking the combination of (1) and (2) as an example, when the values of "PBCH DMRS related information" are different and the values of field A in the PBCH are different, the values of the first index corresponding to different first indexes can be determined. When the values of the first index are determined by the DMRS of the PBCH and the field in the PBCH together, the UE can improve the detection performance through multi-user detection technology.

[0098] Specifically, when the UE performs blind detection on the SSB in the SSB occasion, it can not need to perform blind detection on the value of the SSB index, for example, the above-mentioned field A in the PBCH indicates the SSB index; or field A indicates the beam index, and field B indicates the SSB occasion index. It is also possible that the UE only needs to perform M times of blind detection, for example, the value of the SSB occasion index is indicated by field B in the PBCH, and different SSBs in one SSB occasion are implicitly indicated by the DMRS sequence. It is also possible that the UE needs to perform less than M times of blind detection, for example, part of the value of the beam index is indicated by field C in the PBCH, and the other part is implicitly indicated by the DMRS sequence, and the value of the SSB occasion index is indicated by field B in the PBCH. It is also possible that the UE needs to perform more than M times of blind detection, for example, part of the value of the SSB occasion index is indicated by field D of the PBCH, and the other part of the value of the SSB occasion index and the beam index are implicitly indicated by the DMRS sequence.

[0099] The target SSB can be the first SSB successfully detected by the UE, the SSB with the largest received signal power detected by the UE, or any SSB successfully detected by the UE with a received signal power greater than a preset threshold. After the UE detects the target SSB in the SSB occasion, the SSB occasion is recorded as the target SSB occasion, the receive beam of the UE receiving the target SSB is the target receive beam, the transmit beam of the base station transmitting the target SSB is the target transmit beam, and the first index indicated by the target SSB is the target first index.

[0100] In S520, the base station transmits M second common channels corresponding to the M SSBs.

[0101] The beams used to transmit the M second common channels are the same as the beams used to transmit the M first common channels. Specifically, the beam used to transmit the mth second common channel of the M second common channels is the same as the beam used to transmit the mth first common channel of the M first common channels, where m is a positive integer less than or equal to M. Alternatively, the contents transmitted by the M second common channels are the same, that is, the contents transmitted by the mth first common channel and the mth second common channel are exactly the same, where m1 and m2 are positive integers less than or equal to M, and m1 is not equal to m2.

[0102] The second common channel is used to carry system information other than the system information carried in the first common channel, and this part of the system information together with the system information carried in the first common channel constitutes the basic system information of the cell. For example, the second common channel carries the RMSI described in S510. The second common channel can be a PDCCH scheduling a SIB1, a PDSCH carrying a SIB1, or a PDSCH carrying a SIB1 and a PDCCH scheduling the PDSCH.

[0103] When the first common channel is a synchronization signal, the second common channel can include a PBCH and a PDSCH carrying a SIB1, or a PBCH, a PDSCH carrying a SIB1, and a PDCCH scheduling the PDSCH.

[0104] For convenience of description, SIB1 is used instead of the second common channel in the following description.

[0105] In S521, the UE receives a target SIB1 corresponding to the target SSB. The beam used to receive the target SIB1 is the same as the beam used to receive the target SSB.

[0106] The base station can configure multiple SIB1 transmission locations for SIB1, which can also be referred to as SIB1 occasions. A SIB1 occasion can be a PDCCH monitoring occasion, which can also be referred to as a PDCCH transmission location, for monitoring a PDCCH scheduling SIB1. A SIB1 occasion can also be a PDSCH transmission location for carrying SIB1.

[0107] Optionally, 1 SSB occasion corresponds to 1 SIB1 occasion, and each SIB1 occasion corresponds to a specific time-frequency resource, and there are M SIB1 transmissions on this time-frequency resource, and the used transmission beams correspond to the transmission beams of the M SSBs respectively. Alternatively, 1 SSB occasion corresponds to M SIB1 occasions, that is, each SIB1 corresponds to different time-frequency resources; and the M SIB1 occasions correspond to the M beams used to transmit the M SSBs one by one, that is, the transmission beams of the M SIB1s are also different. In the present application, the time-frequency resources are different, which can mean that the time-domain resources are different but the frequency-domain resources are the same, or the frequency-domain resources are different but the time-domain resources are the same, or both the time-domain resources and the frequency-domain resources are different.

[0108] • SIB1 is DCI scheduled scenario

[0109] In one case, N SSB occasions correspond to N PDCCH transmission locations one by one, and the N PDCCH transmission locations do not overlap. The N PDCCH transmission locations here are the multiple PDCCH transmission locations configured by the base station for SIB1. At each PDCCH transmission location, the base station transmits the same PDCCH using M transmission beams, and the M transmission beams are the same as the transmission beams of the M SSBs in the corresponding SSB occasion. Correspondingly, after the UE detects a target SSB in 1 SSB occasion, the UE uses a target reception beam to detect a PDCCH at the PDCCH transmission location corresponding to the SSB occasion. If the PDCCH is detected, the UE further receives a PDSCH carrying SIB1 on the indicated time-frequency resource using the target reception beam according to the indication of the PDCCH.

[0110] In another case, N*M SSBs are one-to-one corresponding to N*M PDCCH transmission locations, and the N*M PDCCH transmission locations do not overlap. The N*M PDCCH transmission locations here are the multiple PDCCH transmission locations configured by the base station for SIB1 above. At each PDCCH transmission location, the base station transmits PDCCH using a target transmission beam. Correspondingly, after detecting the target SSB, the UE uses the target reception beam to detect the PDCCH. If the PDCCH is detected, the UE further receives the PDSCH carrying SIB1 according to the indication of the PDCCH, using the target reception beam on the indicated time-frequency resource.

[0111] • SIB1 is a non-DCI scheduling scenario, i.e., SIB1 is directly broadcasted.

[0112] The base station can transmit SIB1 on N SIB1 occasions, and the N SIB1 occasions are one-to-one corresponding to N SSB occasions. Each SIB1 occasion corresponds to a time-frequency location, and M times of SIB1 are transmitted at each time-frequency location, and the contents of the M times of SIB1 are the same. After detecting the target SSB, the UE uses the target reception beam to detect SIB1 on the SIB1 occasion corresponding to the target SSB occasion.

[0113] The base station can also transmit SIB1 on N*M SIB1 occasions, and the N*M SIB1 occasions are one-to-one corresponding to N*M SSBs. Each SIB1 occasion corresponds to a time-frequency location, and SIB1 is transmitted once at each time-frequency location. After detecting the target SSB, the UE uses the target reception beam to detect SIB1 on the SIB1 occasion corresponding to the target SSB.

[0114] S530, optionally, the base station transmits M groups of paging channels corresponding to M SSBs.

[0115] The paging channel in the present application can refer to the PDCCH scheduling the paging message, can also refer to the PDSCH carrying the paging message, and can also include the PDCCH scheduling the paging message and the PDSCH carrying the paging message.

[0116] It can be understood that the base station determines whether to send the paging channel to the UE according to whether there is data to be sent to the UE. Therefore, the base station selects one or more from each of the above-mentioned M groups of paging channels to transmit as needed. That is, the base station transmits at most S paging channels in each group of paging channels, and the time-frequency resources of the s-th paging channel in each group of paging channels can be the same, where S is a positive integer and s is a positive integer less than or equal to S. The base station transmits the same transmit beam as the transmit beam used by the base station to transmit the m-th SSB in the M SSBs in the m-th group of paging channels in the M groups of paging channels, and m is a positive integer less than or equal to M. Since the base station does not know the specific location of the UE in the cell, it is necessary to use the M beams to transmit the paging channel to a certain UE. Therefore, the paging messages transmitted in different groups of the M groups of paging channels are the same, that is, the paging messages transmitted by the m1-th group of paging channels and the m2-th group of paging channels are exactly the same. Different paging channels in a group of paging channels can correspond to different UEs or groups of UEs, respectively.

[0117] S531, optionally, the UE receives the target paging channel using the target receiving beam.

[0118] The above-mentioned M SSBs correspond one-to-one to the M groups of paging channels. A group of paging channels corresponding to a target SSB contains the above-mentioned target paging channel sent to the UE. Each of the M groups of paging channels contains S paging channels, and the time-frequency resources of the s-th paging channel in each group of paging channels can be the same, where S is a positive integer and s is a positive integer less than or equal to S. For example, the time-frequency resources of the s-th paging channel in the m1-th group and the s-th paging channel in the m2-th group are the same, where m1 and m2 are positive integers less than or equal to M, and m1 is not equal to m2. The M groups of paging channels are transmitted in a space-division manner, which can reduce the occupation of time-frequency resources by the paging channel, thereby improving the transmission efficiency of the paging channel. In this application, when a group of channels contains only one channel, the group of channels can also be referred to as a channel.

[0119] The M groups of paging channels can also be transmitted in a time-division or frequency-division manner, that is, the time-frequency resources of the s-th paging channel in each group of paging channels are different. For example, the time-frequency resources of the s-th paging channel in the m1-th group and the s-th paging channel in the m2-th group are different.

[0120] After detecting the target SSB, the UE receives the target paging channel using the target receiving beam in the group of paging channels corresponding to the target SSB.

[0121] S540, optionally, the UE transmits a target PRACH, and the beam used by the UE to transmit the target PRACH is the same as the beam used by the UE to receive the target SSB.

[0122] S550, the base station receives M groups of PRACHs corresponding to the M SSBs respectively.

[0123] The beams used by the base station to receive the M groups of PRACHs are the same as the beams used by the base station to transmit the M SSBs. Specifically, the beam used by the base station to receive the mth group of PRACHs in the M groups of PRACHs is the same as the beam used by the base station to transmit the mth SSB in the M SSBs, where m is a positive integer less than or equal to M. The target PRACH transmitted by the UE to the base station is included in the group of PRACHs corresponding to the target SSB. Each of the M groups of PRACHs includes L PRACHs, where L is a positive integer. A PRACH can be defined as a PRACH preamble on a time-frequency resource. PRACHs on different time-frequency resources or different preambles on the same time-frequency resource can correspond to different PRACHs. When L is equal to 1, a group of PRACHs can be referred to simply as a PRACH. The time-frequency resources of the kth PRACH in each of the M groups of PRACHs can be the same, where k is a positive integer less than or equal to L. For example, the time-frequency resources of the kth PRACH in the mth group of PRACHs and the kth PRACH in the n th group of PRACHs are the same, where m and n are positive integers less than or equal to M and m is not equal to n. The M groups of PRACHs are transmitted in a space-division manner, which can reduce the occupation of time-frequency resources by PRACHs and thus improve the transmission efficiency of PRACHs.

[0124] The M groups of PRACHs can also be transmitted in a time-division, frequency-division, or code-division manner, i.e., the time-frequency resources of the s th PRACH in each group of PRACHs are different, or the PRACH preambles used are different, or the scrambling codes used are different. For example, the time-frequency resources of the s th PRACH in the mth group of PRACHs and the s th PRACH in the n th group of PRACHs are different.

[0125] The UE determines the target PRACH in the group of PRACHs corresponding to the target SSB and then transmits the target PRACH using the same beam as that used to receive the target SSB. Since the base station cannot know in advance whether the UE will transmit a PRACH and which PRACH will be transmitted, the base station needs to detect all possible PRACHs, i.e., receive the M groups of PRACHs corresponding to the M SSBs. Here, the reception of PRACHs by the base station can also be referred to as the detection of PRACHs by the base station to confirm whether a PRACH has been transmitted by a UE on the corresponding time-frequency resource.

[0126] Further, the base station can transmit the RAR using the same beam as receiving the target PRACH, and the UE can receive the RAR using the same beam as receiving the target SSB, so as to improve the transmission performance of the RAR. The UE can also transmit the Msg3 using the same beam as receiving the target SSB, and the base station can receive the Msg3 using the same beam as receiving the target PRACH, so as to improve the transmission performance of the Msg3. The base station can also transmit the Msg4 using the same beam as receiving the target PRACH, and the UE can receive the Msg4 using the same beam as receiving the target SSB, so as to improve the transmission performance of the Msg4.

[0127] It can be understood that, in order to implement the functions in the above embodiments, the base station and the terminal include the hardware structure and / or software module corresponding to each function. Those skilled in the art should easily realize that, in combination with the units and method steps of each example described in the embodiments disclosed in the present application, the present application can be realized in the form of hardware or a combination of hardware and computer software. Whether a certain function is implemented in hardware or computer software driven hardware depends on the specific application scenario and design constraints of the technical solution.

[0128] Figure 6 and Figure 7 The structural schematic diagram of a possible communication apparatus provided in the embodiments of the present application is shown. The communication apparatus can be used to implement the functions of the UE or the base station in the above method embodiments, and thus can also achieve the beneficial effects possessed by the above method embodiments. In the embodiments of the present application, the communication apparatus can be one of the terminals 120a-120j as shown in Figure 1 , or can be the base station 110a or 110b as shown in Figure 1 , or can be a module (such as a chip) applied to a terminal or a base station.

[0129] As shown in Figure 6 , the communication apparatus 600 includes a processing unit 610 and a transceiver unit 620. The communication apparatus 600 is used to implement the functions of the UE or the base station in the method embodiments shown in Figure 5 .

[0130] When the communication apparatus 600 is used to implement the functions of the UE in the method embodiments shown in Figure 5 , the transceiver unit 620 can be used to detect M first common channels, and also used to receive a target second common channel corresponding to a target first common channel using a target spatial domain filtering parameter, and used to transmit a target PRACH using the target spatial domain filtering parameter; the processing unit 610 is used to determine the target first common channel detected.

[0131] When the communication apparatus 600 is used to implement the functions of the base station in the method embodiments shown in Figure 5In the method embodiment shown, the base station functions as follows: the transceiver unit 620 is used to transmit M first common channels, to transmit M second common channels corresponding one-to-one with the M first common channels, and to receive M sets of PRACH corresponding one-to-one with the M first common channels.

[0132] For a more detailed description of the processing unit 610 and the transceiver unit 620, please refer to [reference needed]. Figure 5 The relevant descriptions in the method embodiments shown.

[0133] like Figure 7 As shown, the communication device 700 includes a processor 710 and an interface circuit 720. The processor 710 and the interface circuit 720 are coupled to each other. It is understood that the interface circuit 720 can be a transceiver or an input / output interface. Optionally, the communication device 700 may also include a memory 730 for storing instructions executed by the processor 710, or storing input data required by the processor 710 to execute instructions, or storing data generated after the processor 710 executes instructions.

[0134] When the communication device 700 is used to implement Figure 5 In the method shown, the processor 710 is used to implement the functions of the processing unit 610, and the interface circuit 720 is used to implement the functions of the transceiver unit 620.

[0135] When the aforementioned communication device is a chip applied to a terminal, the terminal chip implements the functions of the terminal in the above method embodiments. The terminal chip receives information from other modules (such as radio frequency modules or antennas) in the terminal, which is information sent to the terminal by the base station; or, the terminal chip sends information to other modules (such as radio frequency modules or antennas) in the terminal, which is information sent to the base station by the terminal.

[0136] When the aforementioned communication device is a module applied to a base station, the base station module implements the functions of the base station in the above method embodiments. The base station module receives information from other modules (such as radio frequency modules or antennas) in the base station, information sent by the terminal to the base station; or, the base station module sends information to other modules (such as radio frequency modules or antennas) in the base station, information sent by the base station to the terminal. Here, the base station module can be the baseband chip of the base station, or a DU (Digital Unit) or other modules. The DU can be a DU under an Open Radio Access Network (O-RAN) architecture.

[0137] It is to be understood that the processor in the embodiments of the present application can be a central processing unit (CPU), and can also be other general-purpose processors, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, transistor logic devices, hardware components or any combination thereof. The general-purpose processor can be a microprocessor or any conventional processor.

[0138] The method steps in the embodiments of the present application can be implemented in hardware, or in software instructions executable by a processor. The software instructions can be composed of corresponding software modules, which can be stored in a random access memory, a flash memory, a read-only memory, a programmable read-only memory, an erasable programmable read-only memory, an electrically erasable programmable read-only memory, a register, a hard disk, a mobile hard disk, a CD-ROM or any other form of storage medium well known in the art. An exemplary storage medium is coupled to the processor, so that the processor can read information from, and write information to, the storage medium. The storage medium can also be a component of the processor. The processor and the storage medium can be located in an ASIC. In addition, the ASIC can be located in a base station or a terminal. The processor and the storage medium can also exist as discrete components in the base station or the terminal.

[0139] In the above embodiments, all or part of the embodiments can be implemented by software, hardware, firmware or any combination thereof. When implemented by software, all or part of the embodiments can be implemented in the form of a computer program product. The computer program product includes one or more computer programs or instructions. When the computer programs or instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of the present application are performed. The computer can be a general purpose computer, a special purpose computer, a computer network, a network device, a user equipment or other programmable apparatus. The computer programs or 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 programs or instructions can be transferred from one website site, computer, server or data center to another website site, computer, server or data center through wired or wireless manner. The computer readable storage medium can be any available medium accessible by a computer or a data storage device such as a server, data center and the like integrated with one or more available media. The available media can be a magnetic medium, such as a floppy disk, a hard disk, a magnetic tape; an optical medium, such as a digital video disc; and a semiconductor medium, such as a solid state disk. The computer readable storage medium can be a volatile or non-volatile storage medium, or can include both volatile and non-volatile storage media.

[0140] In various embodiments of the present application, the terms and / or descriptions of different embodiments are consistent and can be referred to each other if there is no special description and logical conflict, and the technical features in different embodiments can be combined to form new embodiments according to their inherent logical relationship.

[0141] In the present application, "at least one" means one or more, and "multiple" means two or more. The association relationship between the associated objects is described, which means that there can be three kinds of relationships, for example, A and / or B, which can represent the following cases: A exists alone, A and B exist together, and B exists alone, where A and B can be singular or plural. In the textual description of the present application, the character " / ", generally represents that the associated objects before and after are in an "or" relationship; in the formula of the present application, the character " / ", represents that the associated objects before and after are in a "division" relationship.

[0142] It can be understood that the various numbers involved in the embodiments of the present application are only distinguished for convenience of description, and are not used to limit the scope of the embodiments of the present application. The size of the serial number of the above processes does not mean the execution order, and the execution order of the processes should be determined according to its function and inherent logic.

Claims

1. An initial access method, characterized in that, Executed by a terminal or a module within a terminal, including: M first common channels are detected to determine the target first common channel. The first common channel includes a synchronization signal and a physical broadcast channel. The physical broadcast channel carries a partial minimum system information (MSI) of the cell. The partial MSI indicates the transmission configuration of the remaining minimum system information (RMSI) of the cell. The time-frequency resources of the M first common channels are completely identical, and M is an integer greater than 1. The target spatial filtering parameters are used to receive the target second common channel corresponding to the target first common channel, the target second common channel carries the RMSI, and the target spatial filtering parameters are the spatial filtering parameters used when receiving the target first common channel; The target physical random access channel (PRACH) is transmitted using the target spatial filtering parameters. Among them, the M first common channels correspond one-to-one with the M second common channels, the M second common channels include the target second common channel, and the M second common channels have the same time and frequency resources.

2. The method according to claim 1, characterized in that, The method further includes: The target first index corresponding to the target first common channel is determined based on the first information of the target first common channel, wherein the values ​​of the first index indicated by different first common channels among the M first common channels are different.

3. The method according to claim 2, characterized in that, The first information is at least one of the following: Information related to the demodulation reference signal (DMRS) of the first common channel; The index field in the first public channel; and, The parameters in the channel coding, modulation, or scrambling process of the first common channel.

4. The method according to claim 3, characterized in that, The DMRS-related information is one of the following: The sequence index of the DMRS; the initialization identifier value of the DMRS sequence; the index of the resource particle position of the DMRS; or, the index of the orthogonal mask of the DMRS.

5. The method according to claim 3 or 4, characterized in that, The index field indicates the target first common channel among the M first common channels.

6. The method according to any one of claims 1 to 4, characterized in that, The M first common channels correspond one-to-one with the M groups of PRACHs. The group of PRACHs corresponding to the target first common channel includes the target PRACH. Each group of PRACHs in the M groups contains L PRACHs. The k-th PRACH in each group of the M groups has the same time-frequency resources, where L is a positive integer and k is a positive integer less than or equal to L.

7. The method according to any one of claims 1 to 4, characterized in that, The method further includes: Receive the target paging channel using the target spatial filtering parameters.

8. The method according to claim 7, characterized in that, The M first common channels correspond one-to-one with the M groups of paging channels. The group of paging channels corresponding to the target first common channel includes the target paging channel. Each of the M groups of paging channels contains S paging channels. The time-frequency resources of the s-th paging channel in each of the M groups of paging channels are the same, where S is a positive integer and s is a positive integer less than or equal to S.

9. An initial access method, characterized in that, Performed by a network device or a module within a network device, including: M first common channels are transmitted, wherein the first common channels include a synchronization signal and a physical broadcast channel, the physical broadcast channel carries a partial minimum system information (MSI) of the cell, the partial MSI indicates the transmission configuration of the remaining minimum system information (RMSI) of the cell, and the time-frequency resources of the M first common channels are completely identical, where M is an integer greater than 1; M second common channels are transmitted, each corresponding to one of the M first common channels. The spatial filtering parameters used to transmit the M second common channels are the same as those used to transmit the M first common channels. The time-frequency resources of the M second common channels are the same. Receive M groups of Physical Random Access Channels (PRACHs) that correspond one-to-one with the M first common channels. The spatial filtering parameters used in receiving the m-th PRACH in the M groups of PRACHs are the same as those used in sending the m-th first common channel in the M groups of first common channels, where m is a positive integer less than or equal to M.

10. The method according to claim 9, characterized in that, The first information of the first common channel indicates the first index, wherein the values ​​of the first index indicated by different first common channels among the M first common channels are different.

11. The method according to claim 10, characterized in that, The first information is at least one of the following: Information related to the demodulation reference signal (DMRS) of the first common channel; The index field in the first public channel; and, The parameters in the channel coding, modulation, or scrambling process of the first common channel.

12. The method according to claim 11, characterized in that, The DMRS-related information is one of the following: The sequence index of the DMRS; the initialization identifier value of the DMRS sequence; the index of the resource particle position of the DMRS; or, the index of the orthogonal mask of the DMRS.

13. The method according to claim 11 or 12, characterized in that, The index field indicates the target first common channel among the M first common channels.

14. The method according to any one of claims 9 to 12, characterized in that, Each of the M groups of PRACH contains L PRACHs, and the k-th PRACH in each of the M groups of PRACH has the same time-frequency resources, where L is a positive integer and k is a positive integer less than or equal to L.

15. The method according to any one of claims 9 to 12, characterized in that, The method further includes: M sets of paging channels are transmitted, each corresponding to one of the M first common channels. The spatial filtering parameters used in transmitting the m-th paging channel in the M sets of paging channels are the same as those used in transmitting the m-th first common channel in the M sets of first common channels, where m is a positive integer less than or equal to M.

16. The method according to claim 15, characterized in that, Each of the M paging channels contains at most S paging channels. The s-th paging channel in each of the M paging channels has the same time-frequency resources, where S is a positive integer and s is a positive integer less than or equal to S.

17. A communication device, characterized in that, The processor includes a processor for performing the method as described in any one of claims 1 to 8; or, the processor is configured to perform the method as described in any one of claims 9 to 16.

18. A communication device, characterized in that, The device includes a processor and an interface circuit. The interface circuit is used to receive signals from other communication devices besides the communication device and transmit them to the processor, or to send signals from the processor to other communication devices besides the communication device. The processor is used to implement the method as described in any one of claims 1 to 8, or to implement the method as described in any one of claims 9 to 16, through logic circuits or execution code instructions.

19. A computer-readable storage medium storing computer instructions, characterized in that, When the computer instructions are executed by the communication device, the communication device performs the method as described in any one of claims 1 to 8, or performs the method as described in any one of claims 9 to 16.

20. A computer program product, characterized in that, The computer program product includes a computer program that, when run by a communication device, causes the communication device to perform the method as described in any one of claims 1 to 8, or to perform the method as described in any one of claims 9 to 16.

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