6g intelligent reflecting surface assisted network cell search method and device

Abstract

The application discloses a 6G intelligent reflecting surface assisted network cell search method and device, relates to the field of wireless communication networks, and particularly relates to a synchronization device; first, for the communication scenario composed of a base station, a terminal and an IRS, three ways are adopted to expand the SSB number to match the base station IRS joint beam quantity; then, when the IRS is dynamically opened / closed, the base station re-determines the SSB number of one-time beam scanning according to the beam scanning requirement, and updates the signaling content of the base station IRS joint broadcast according to the SSB number expansion; on this basis, the base station and IRS joint broadcast process during SSB transmission is carried out; finally, when the terminal performs cell search, the terminal detects SSBs on predefined frequency points according to a default period, and if the terminal is configured to receive multiple predefined directions, detection is performed in each receiving predefined direction in a polling mode; under different SSB number expansion methods, corresponding SIB1 and OSI are parsed according to the SSB reception. The application realizes user discovery of the best base station IRS joint beam.

Description

Technical Field

[0001] This invention relates to the field of wireless communication networks, and particularly to synchronization devices, specifically a 6G intelligent reflector-assisted network cell search method and device. Background Technology

[0002] Intelligent Reflecting Surface (IRS): A new type of network element composed of a large number of low-cost passive units (may also be configured with a small number of active units with transceiver functions, or add a power amplifier to all passive units). Each unit (or combination of multiple units) can independently adjust the amplitude and / or phase of the incident signal and reflect / transmit it to achieve beamforming.

[0003] 5G / B5G base stations control one or more IRSs (Incoming Reception Controllers) via wireless / wired communication to jointly provide uplink and downlink wireless communication for user terminals. The base station is configured with one or more antennas and sets one or more base station beam pre-directions for base station beamforming. The IRS sets one or more predefined reflection predefined directions, and the terminal sets one or more predefined reception directions. The base station and IRS together can form a base station-IRS joint beam, which is a combination of the base station beam predefined directions and the IRS reflection predefined directions, such as... Figure 1 As shown.

[0004] The number of combined beams formed by IRS and base stations far exceeds the current network, and the number of configurable SSBs is insufficient (maximum 8 for low frequency and 64 for high frequency). For example, assuming a base station is configured with 8 predefined beam directions and 4 IRSs are deployed to assist the base station's transmission, with each IRS configured with 2 predefined reflection directions, the number of beams that the base station and IRS may form reaches 8 (base station only) + 8 × 4 × 2 (base station and IRS combined) = 72. In scenarios with dense IRS deployment, the number of beams will be even greater.

[0005] Therefore, the current NR cell search process cannot meet the needs of the IRS-assisted network. The existing process only supports users to discover and access the optimal beam pre-direction of the base station, and lacks a method for scanning and discovering the joint beam of the base station IRS. Users cannot discover the optimal IRS and the predefined direction of IRS reflection. Moreover, the dynamic opening / closing of the IRS will affect the required SSB (Synchronization Signal) and PBCH (Synchronization Signal and PBCH block) configuration. The current network lacks the corresponding process to dynamically configure the number of SSBs and the joint scanning process of the base station IRS. At the same time, there is a lack of signaling to support the above processes.

[0006] Concept Explanation:

[0007] SSB: Composed of three parts: primary synchronization signal, secondary synchronization signal and physical broadcast channel, it is broadcast by the base station and used for terminal downlink synchronization and cell search.

[0008] Demodulation Reference Signal (DMRS): Used for correlation demodulation of the channel. The SSB number or part of the SSB number is carried in the SSB through cyclic shift.

[0009] Physical Broadcast Channel (PBCH): A part of the SSB, carrying system information such as cell ID and used in the cell search process;

[0010] Master Information Block (MIB): Carried by PBCH, it contains important cell information and is also used to indicate SIB1;

[0011] System Information Block 1 (SIB1): Used to carry key information required for terminal access to the cell, such as random access parameters;

[0012] Other System Information (OSI): refers to system messages other than SIB1;

[0013] Physical Random Access Channel (PRACH): Used to send access requests;

[0014] ACK / NACK: Acknowledgment / Negative message;

[0015] Base station beam predefined direction set: Multiple beamforming configurations pre-set on the base station side. When the base station communicates with the terminal, the base station implements one (or more) of these beamforming configurations.

[0016] IRS reflection predefined direction set: multiple IRS passive beamforming configurations pre-set on the IRS side, one (or more) of the IRS passive beamforming configurations are implemented when the IRS-assisted base station communicates with the terminal;

[0017] The correspondence between IRS and base station beam predefined directions is stored on the base station side, indicating which base station beam predefined directions each IRS and its reflection predefined direction are allowed to form a base station-IRS joint beam with;

[0018] Service beam set: Stored on the base station side, it consists of all implementable base station beams, IRS joint beams, and predefined directions of base station beams that can be implemented individually (without IRS joint beams);

[0019] IRS non-reflection: A state in which the base station schedules the IRS, and all IRS units are turned off;

[0020] Explicit SSB extension period: an SSB number extension method in which SSBs in multiple SSB periods are used for one beam scan. The base station needs to inform the terminal (1) how many SSBs in total have been combined; (2) which period of the received SSB is in the extension period.

[0021] Implicit SSB Extended Period: A method for extending the number of SSBs, in which SSBs within multiple SSB periods are used for one beam scan, and the terminal does not need to know the relevant information about the SSB extended period. Summary of the Invention

[0022] To address the aforementioned issues, this invention proposes a 6G intelligent reflector-assisted network cell search method and device, which improves upon the existing NR cell search process and enables users to discover the optimal base station IRS joint beam.

[0023] The specific steps of the 6G intelligent reflector-assisted network cell search method are as follows:

[0024] Step 1: In a communication scenario consisting of a base station, a terminal, and an IRS, the cell search process of NR cannot meet the number of SSBs required by the IRS auxiliary network. Expand the number of SSBs to match the number of joint beams of the base station and the IRS.

[0025] The method for expanding the number of SSBs is one of the following methods:

[0026] a) Increase the number of SSB number bits: reserve and dynamically schedule the number of bits jointly carried by DMRS and PBCH, supporting a maximum number of SSBs less than 2, which is a power of the number of bits to be scheduled.

[0027] b) Explicit SSB extension period: Define the SSB extension period, and let the SSBs in multiple SSB periods be used for one beam scan; The base station determines and informs the terminal of at least one of the following: (1) the number of periods of the joint SSB; (2) the period in which the received SSB is in the extension period;

[0028] c) Implicit SSB extension period: Define the SSB extension period. SSBs within multiple SSB periods are used for one beam scan. The base station determines at least one of the following information: (1) the number of periods of the joint SSB; (2) which period of the transmitted SSB is in the extension period. The terminal is not explicitly informed. The SSBs in the extension period are configured to correspond to different PRACH configurations by modifying system messages (MIB, SIB1, OSI, etc.).

[0029] Step 2: Dynamically enable / disable the IRS. The base station re-determines the number of SSBs for a beam scan based on the beam scan requirements, and updates the signaling content jointly broadcast by the base station and the IRS according to the SSB number expansion method.

[0030] When an IRS controlled by the base station is added, deleted, or rescheduled, the base station determines the number of SSBs required for one beam scan based on the new number of IRSs and the scheduling status. The number of SSBs is determined by (1) the number of IRSs currently enabled, (2) the number of IRS reflection predefined directions, (3) the number of base station beam predefined directions, (4) the combination logic of base station beam predefined directions and IRS reflection predefined directions, and (5) the number of SSBs allocated to each base station IRS joint beam and base station beam.

[0031] For different SSB number expansion methods, the following different signaling update methods are used respectively:

[0032] a) Increase the number of SSB number bits: Update the SSB map in the SIB1 / OSI information. This signaling is used to indicate the SSB scheduling status within a period. The SSB map consists of N bits. When M SSBs are called, M bits in the SSB map are 1 and the rest are 0, and N is always greater than M.

[0033] b) Explicit SSB extension cycle: Update at least one of the following signaling for information: (1) how many cycles of SSB have been combined; the signaling used includes: (i) enumeration form: the base station side and the terminal side predetermine the number of possible combinations and indicate which configuration is it through the SSB / SIB1 / OSI bearer field; (ii) direct indication: the SSB / SIB1 / OSI bearer information directly indicates the number of combinations.

[0034] For the period in which the SSB received in the extended period is in the extended period, the signaling used is direct indication. The relationship between the number of bits in the information field used for indication and the maximum number of combinations is: the number of bits in 2 raised to the power of the maximum number of combinations.

[0035] c) Implicit SSB extension cycle: Based on the new number of SSBs, the base station updates the correspondence between each SSB and PRACH within the extension cycle, and updates the PRACH configuration signaling in each system message (MIB, SIB1, OSI, etc.) that needs to be sent to the terminal.

[0036] Step 3: Based on the determined number of SSBs and the signaling content that the base station and IRS need to broadcast jointly, determine and implement the joint broadcasting process of the base station and IRS when sending SSBs.

[0037] The specific process is as follows:

[0038] Step 1: Configure the correspondence between the IRS in the cell and the predefined direction of the base station beam, that is, which base station beam predefined directions each IRS and its reflection predefined direction are allowed to form a joint beam with;

[0039] A certain reflection predefined direction of an IRS can also form a joint beam with multiple base station beam predefined directions; multiple IRS reflection predefined directions can also be set to simultaneously form a joint beam with a base station beam predefined direction.

[0040] Step 2: Determine all possible serving beam sets for the cell, that is, all possible beam forms formed by the base station beam predefined direction alone or by the base station beam predefined direction combined with the IRS reflection predefined direction.

[0041] Step 3: Based on the determined number of SSBs and the signaling content that the base station and IRS need to broadcast together, establish the correspondence between SSBs and service beams. The correspondence requires that each service beam corresponds to at least one SSB.

[0042] Step 4: Based on the correspondence, when the base station transmits a certain SSB, the base station and IRS implement the service beam corresponding to that SSB. When the base station transmits the SIB1 and OSI corresponding to that SSB, it also implements the service beam corresponding to that SSB, thus realizing joint broadcasting by the base station and IRS.

[0043] In particular, IRS behavior can take into account the propagation delay from the base station to the IRS, that is, lag the transmission delay from one base station to the IRS to achieve stricter timing alignment.

[0044] Step 4: When the terminal performs cell search, it detects SSBs on the predefined frequency points according to the default period, parses the SSB number and other bearer information, and receives the SIB1 and OSI corresponding to the SSB.

[0045] If the terminal is configured with multiple predefined reception directions, the terminal performs detection in each predefined reception direction through polling. Under the three SSB number expansion methods, the terminal continues to perform the following behaviors:

[0046] a) Increase the number of SSB number bits: The terminal determines the SSB with the strongest received signal strength within the reception period by measurement, and parses the SSB number and other SSB bearer information. The terminal then has two options for behavior:

[0047] Option 1: The terminal continues to receive the SIB1 and OSI corresponding to the SSB based on the information currently parsed by the SSB bearer;

[0048] Option 2: After the terminal learns the base station's beam scan cycle and SSB arrangement, it measures all SSBs within the beam scan cycle to determine the strongest SSB. The terminal continues to receive the SIB1 and OSI corresponding to the strongest SSB based on the information carried by the strongest SSB. If the terminal is configured with multiple predefined receiving directions, the terminal performs the above operation in each predefined receiving direction by polling.

[0049] b) Explicit SSB extension period: The terminal determines the SSB with the strongest signal strength received within the reception period by measurement, and parses (1) how many SSBs were combined, (2) which period of the received SSB is in the extension period, (3) the SSB number, (4) and other SSB bearer information. The terminal then has two options for its behavior:

[0050] Option 1: The terminal continues to receive the SIB1 and OSI corresponding to the SSB based on the information currently parsed by the SSB bearer;

[0051] Option 2: After the terminal learns the base station's beam scan cycle and SSB arrangement, it measures all SSBs within the beam scan cycle to determine the strongest SSB. The terminal continues to receive the SIB1 and OSI corresponding to the strongest SSB based on the information carried by the strongest SSB. If the terminal is configured with multiple predefined receiving directions, the terminal performs the above operation in each predefined receiving direction by polling.

[0052] c) Implicit SSB extended period: The terminal determines the SSB with the strongest signal strength received within the reception period by measurement, and parses (1) the SSB number (2) and other SSB bearer information. The terminal continues to receive the SIB1 and OSI corresponding to the SSB based on the currently parsed SSB bearer information.

[0053] The 6G intelligent reflector-assisted network cell search device includes:

[0054] The first determining module is used to determine the number of SSBs in a single scan and to determine the signaling content of the joint broadcast by the base station and IRS based on the SSB number expansion method.

[0055] The second determining module is used to determine the joint broadcast process of the base station and IRS when the SSB is sent, based on the number of SSBs and the signaling content that the base station and IRS need to broadcast together.

[0056] Network-side device: includes a memory, a processor, and a computer program stored in the memory and executable on the processor; when the processor executes the program, it implements the steps of the cell search method described above;

[0057] Intelligent reflective surface device: includes a memory, a processor, and a computer program stored in the memory and executable on the processor; when the processor executes the program, it implements the steps of the cell search method described above;

[0058] Terminal device: includes a memory, a processor, and a computer program stored in the memory and executable on the processor; when the processor executes the program, it implements the steps of the cell search method as described above.

[0059] The advantages of this invention are:

[0060] 1. The present invention provides a 6G intelligent reflector-assisted network cell search method and device, which solves the problem that the number of SSBs required for a single scan of a cell search in an IRS-assisted network exceeds the maximum number of SSBs specified by the current network, resulting in the inability to match SSBs with the serving beam;

[0061] 2. The present invention provides a 6G intelligent reflector-assisted network cell search method and device, which fills the gap in the existing process for scanning and discovering the base station IRS joint beam, and for users to discover the best IRS and IRS reflection predefined direction. It realizes the terminal to discover the best base station and IRS joint service beam, that is, the best combination of base station beam predefined direction, IRS, and IRS reflection predefined direction.

[0062] 3. The present invention provides a 6G intelligent reflector-assisted network cell search method and device, which solves the problem that the existing network lacks a method for dynamically configuring the number of SSBs and the joint scanning process of the base station and IRS when the IRS is dynamically turned on / off. When the IRS is dynamically scheduled, the base station and IRS reconfigure the relevant cell search.

[0063] 4. The present invention provides a 6G intelligent reflector-assisted network cell search method and device, and designs related signaling to support the proposed 6G intelligent reflector-assisted network cell search method;

[0064] 5. The present invention provides a 6G intelligent reflector-assisted network cell search method and device, which utilizes IRS technology to improve the base station SSB transmission performance and cell coverage capability, especially in urban blind spots, back streets and alleys and other scenarios. Attached Figure Description

[0065] Figure 1 This is a schematic diagram of the existing 6G smart reflector-assisted network cell search system structure;

[0066] Figure 2 This is a flowchart of a 6G intelligent reflector-assisted network cell search method according to the present invention;

[0067] Figure 3 This is a structural diagram of a communication system for 6G intelligent reflector-assisted network cell search according to the present invention;

[0068] Figure 4 This is a schematic diagram of the first determining module of the 6G intelligent reflector-assisted network cell search device of the present invention;

[0069] Figure 5 This is a schematic diagram of the second determining module of the 6G intelligent reflector-assisted network cell search device of the present invention;

[0070] Figure 6 This is a schematic diagram of the third determining module of the 6G intelligent reflector-assisted network cell search device of the present invention;

[0071] Figure 7 This is a schematic diagram of the network side equipment of the 6G intelligent reflective surface assisted network cell search device of the present invention;

[0072] Figure 8 This is a schematic diagram of the intelligent reflector device of the 6G intelligent reflector-assisted network cell search device of the present invention;

[0073] Figure 9 This is a schematic diagram of the terminal device of the 6G intelligent reflective surface assisted network cell search device of the present invention. Detailed Implementation

[0074] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

[0075] The 6G intelligent reflector-assisted network cell search method, such as Figure 2 As shown, the specific steps are as follows:

[0076] Step 1: In a communication scenario consisting of a base station, a terminal, and an IRS, the cell search process of NR cannot meet the number of SSBs required by the IRS auxiliary network. Expand the number of SSBs to match the number of joint beams of the base station and the IRS.

[0077] The SSB number expansion method mainly addresses the problem that the number of SSBs cannot match the number of joint beams of the base station and IRS. The following methods can be used to expand the number of SSBs within a single beam scan of the base station and IRS:

[0078] a) Increase the number of SSB numbering bits: By reserving and dynamically scheduling the number of bits jointly carried by DMRS and PBCH, the maximum number of SSBs supported is less than 2, which is a power of the number of bits to be scheduled; for example: reserve 5 bits, and schedule 4 bits when it is necessary to label 15 SSBs.

[0079] b) Explicit SSB extension period: Define the SSB extension period, and use the SSBs in multiple SSB periods for one beam scan; Compared with the prior art, the base station needs to determine and inform the terminal of at least one of the following information in the cell search process: (1) the number of periods of the joint SSB; (2) which period of the received SSB in the extension period.

[0080] c) Implicit SSB extension period: Same as method b) SSBs in multiple SSB periods are used for one beam scan. Compared to method b), two additional pieces of information (i.e., (1) how many SSBs in total periods are combined; (2) which period of the received SSB in the extension period) are only known on the base station side. By modifying system messages (MIB, SIB1, OSI, etc.), the SSBs in the extension period are uniformly mapped to PRACH resources to achieve the reporting of the best combined beam.

[0081] Step 2: Dynamically enable / disable the IRS, reconfigure the number of SSBs for a single beam scan at the base station, and update the signaling content jointly broadcast by the base station and the IRS according to the SSB number expansion method.

[0082] When an IRS controlled by the base station is added, deleted, or rescheduled, the base station determines the number of SSBs required for one beam scan based on the new number of IRSs and the scheduling status. The number of SSBs is determined by at least one of the following: (1) the number of IRSs that are enabled, (2) the number of IRS reflection predefined directions, (3) the number of base station beam predefined directions, (4) the combination logic of base station beam predefined directions and IRS reflection predefined directions, and (5) the number of SSBs allocated to each base station IRS joint beam and base station beam.

[0083] For example: A base station has the following configuration:

[0084] (1) The number of IRSs is 3; (2) Each IRS has 2 reflection pre-directions; (3) The number of base station beam predefined directions is 4; (4) The combination logic of base station beam predefined directions and IRS reflection predefined directions is as follows: base station beam predefined directions #1, #2, and #3 can form a joint beam with the two reflection pre-directions of IRS #1, #2, and #3 respectively, and base station beam predefined directions #1, #2, and #3 can also serve users independently. Base station beam predefined direction #4 does not form a joint beam with the IRS; (5) Each base station IRS joint beam and base station beam is allocated 2 SSBs. At this time, the number of SSBs required for cell search is:

[0085] (4 (number of base station beams that can serve users individually) + 3 × 1 × 2 (number of base station IRS combined beams)) × 2 (number of SSBs per beam) = 20.

[0086] In the example above, if the base station beam predefined directions #1, #2, and #3 cannot serve users individually, then the number of SSBs required for cell search is:

[0087] (1 (number of base station beams that can serve users individually) + 3 × 1 × 2 (number of base station IRS combined beams)) × 2 (number of SSBs per beam) = 14.

[0088] When the number of SSBs is reconfigured, the signaling, including system messages broadcast by the base station, also needs to be updated. For different SSB number expansion methods, the following different signaling update methods apply:

[0089] a) Increase the number of SSB number bits: It is necessary to update the SSB map (bit map) in the SIB1 / OSI information. This signaling is used to indicate the SSB scheduling status within a period. The SSB map consists of N bits. When M SSBs are called, M bits in the SSB map are 1 and the rest are 0, and N is always greater than M.

[0090] b) Explicit SSB extension cycle: The base station needs to inform the terminal of at least one of the following information in the cell search process: (1) The SSBs of several cycles have been combined;

[0091] The signaling used includes: (i) enumeration form: the base station side and the terminal side predetermine the number of possible combinations, such as: {2, 4, 8, 16}, and indicate which configuration is used through the SSB / SIB1 / OSI bearer field, such as "11" representing the number of combinations as 16; (ii) direct indication: the SSB / SIB1 / OSI bearer information directly indicates the number of combinations; for example, when the number of combinations is 16, the information carried is the binary form of the number of combinations minus one: "001111". At this time, the range of the number of combinations that this information field can indicate is 2 ("000001") to 64 ("111111"). When the information field is "000000", it means that SSB cycle combination is not performed. The number of bits in the information field is agreed upon in advance by the base station side and the terminal side according to the requirements.

[0092] For the SSB received in information (2) within the extended period, the signaling used is direct indication. The relationship between the number of bits in the information field used for indication and the number of periods of the joint SSB is: the power of the number of bits of 2 is greater than or equal to the number of periods of the joint SSB.

[0093] c) Implicit SSB extension period: at least one of the following two additional pieces of information: (1) how many SSBs were combined; (2) in which period of the received SSB was updated at the base station, and the base station updated the correspondence between each SSB and PRACH resources in the extension period based on the new number of SSBs, and updated the PRACH configuration signaling in each system message (MIB, SIB1, OSI, etc.) that needs to be sent to the terminal.

[0094] Step 3: Based on the determined number of SSBs and the signaling content that the base station and IRS need to broadcast jointly, determine and implement the joint broadcasting process of the base station and IRS when sending SSBs.

[0095] Design the base station and IRS joint broadcast process and define the relevant signaling and configuration procedures to improve SSB transmission performance and enable users to discover the best base station and IRS joint beam. The base station determines the number of SSBs in a single scan during cell search and the broadcast signaling content based on the above method, and then determines the base station and IRS behavior when sending SSBs.

[0096] The specific process is as follows:

[0097] Step 1: Configure the correspondence between the IRS in the cell and the predefined direction of the base station beam, that is, which base station beam predefined directions each IRS and its reflection predefined direction are allowed to form a joint beam with;

[0098] For example: A base station has four pre-defined beam directions #1, #2, #3, and #4, and three IRSs #1, #2, and #3 are enabled. Each IRS has two pre-defined reflection directions. Here, the base station's pre-defined beam directions #1, #2, and #3 are configured to form a joint beam with the two pre-defined reflection directions of IRSs #1, #2, and #3, respectively. Base station pre-defined beam directions #1, #2, and #3 can also serve users independently. Base station pre-defined beam direction #4 does not form a joint beam with any IRS. The correspondence between IRSs and base station pre-defined beam directions within the cell in this example is shown in the table below:

[0099] Table 1

[0100]

[0101] Note: A certain reflection predefined direction of an IRS can also form a joint beam with multiple base station beam predefined directions. For example, base station beam predefined directions #1 and #2 can be set to form a joint beam with the two reflection predefined directions of IRS #1.

[0102] Note: The reflection predefined directions of multiple IRSs can also be set to form a joint beam with a base station beam predefined direction at the same time. For example, the base station beam predefined direction #1 can be set to be implemented simultaneously with the reflection predefined direction #1 of IRS #1 plus the reflection predefined direction #2 of IRS #1 to form a joint beam.

[0103] Step 2: Determine all possible serving beam sets for the cell, i.e., all possible beam forms formed by the base station alone or by the base station in conjunction with the IRS.

[0104] Continuing with the example from step one, all possible service beams for this instance are listed in the table below:

[0105] Table 2

[0106]

[0107]

[0108] Note: No reflection means that the IRS is temporarily shut down all units. In this invention, "IRS off" means a long-term off state.

[0109] Step 3: Based on the determined number of SSBs and the signaling content that the base station and IRS need to broadcast together, establish the correspondence between SSBs and service beams. The correspondence requires that each service beam corresponds to at least one SSB.

[0110] Continuing with the examples in steps one and two, if each serving beam requires two SSBs, the possible correspondence between an SSB and a serving beam is shown in the table below:

[0111] Table 3

[0112]

[0113]

[0114] Step 4: Based on the correspondence, when the base station transmits a certain SSB, the base station and IRS implement the service beam corresponding to that SSB. When the base station transmits the SIB1 and OSI corresponding to that SSB, it also implements the service beam corresponding to that SSB, thus realizing joint broadcasting by the base station and IRS.

[0115] In particular, IRS behavior can take into account the propagation delay from the base station to the IRS, that is, lag the transmission delay from one base station to the IRS to achieve stricter timing alignment.

[0116] Step 4: When the terminal performs cell search, it detects SSBs on predefined frequency points according to the default period. If the terminal is configured with multiple predefined reception directions, the terminal performs detection in each predefined reception direction through polling. Under the three SSB number expansion methods, the terminal continues to perform the following behaviors:

[0117] a) Increase the number of SSB number bits: The terminal determines the SSB with the strongest received signal strength within the reception period by measurement, and parses the SSB number and other SSB bearer information. The terminal then has two options for behavior:

[0118] Option 1: The terminal continues to receive the SIB1 and OSI corresponding to the SSB based on the information currently parsed by the SSB bearer;

[0119] Option 2: After the terminal learns the base station's beam scanning period and SSB arrangement, it measures all SSBs within the SSB extension period to determine the strongest SSB. The terminal continues to receive the SIB1 and OSI corresponding to the strongest SSB based on the information carried by the strongest SSB. If the terminal is configured with multiple predefined receiving directions, the terminal performs the above operation in each predefined receiving direction by polling.

[0120] b) Explicit SSB extension period: The terminal determines the SSB with the strongest signal strength received within the reception period by measurement, and parses (1) how many SSBs were combined, (2) which period of the received SSB is in the extension period, (3) the SSB number, (4) and other SSB bearer information. The terminal then has two options for its behavior:

[0121] Option 1: The terminal continues to receive the SIB1 and OSI corresponding to the SSB based on the information currently parsed by the SSB bearer;

[0122] Option 2: After the terminal learns the base station's beam scanning period and SSB arrangement, it measures all SSBs within the SSB extension period to determine the strongest SSB. The terminal continues to receive the SIB1 and OSI corresponding to the strongest SSB based on the information carried by the strongest SSB. If the terminal is configured with multiple predefined receiving directions, the terminal performs the above operation in each predefined receiving direction by polling.

[0123] c) Implicit SSB extended period: The terminal determines the SSB with the strongest signal strength received within the reception period by measurement, and parses (1) the SSB number (2) and other SSB bearer information. The terminal continues to receive the SIB1 and OSI corresponding to the SSB based on the currently parsed SSB bearer information.

[0124] The 6G intelligent reflector-assisted network cell search device, such as Figure 3 As shown, it includes: a first determining module and a second determining module connected in sequence, the second determining module being connected to both the network-side device and the intelligent reflective surface device; wherein, the network-side device communicates with the terminal device via SSB, and the terminal device is connected to the third determining module.

[0125] First module to be determined: such as Figure 4 As shown, the number of SSBs in a single scan is determined, and the signaling content of the joint broadcast by the base station and IRS is determined based on the SSB number expansion method.

[0126] Second determination module: such as Figure 5 As shown, this is used to determine the joint broadcast process of the base station and IRS when the SSB is sent, based on the number of SSBs and the signaling content that the base station and IRS need to broadcast together.

[0127] The third determining module: such as Figure 6 As shown, it is used to determine the subsequent SSB, SIB1 and OSI reception process based on the SSB with the strongest signal strength and its bearer information within the reception period determined by measurement;

[0128] Network-side devices: such as Figure 7 As shown, it includes a transceiver, a memory, a processor, and a computer program stored in the memory and executable on the processor; when the processor executes the program, it implements the steps of the cell search method described above.

[0129] Intelligent reflective surface devices: such as Figure 8 As shown, it includes a cell array, a memory, a processor, and a computer program stored in the memory and executable on the processor; when the processor executes the program, it implements the steps of the cell search method described above.

[0130] Terminal equipment: such as Figure 9As shown, it includes a transceiver, a memory, a processor, and a computer program stored in the memory and executable on the processor; when the processor executes the program, it implements the steps of the cell search method described above.

Claims

1. A 6G intelligent reflecting surface assisted network cell search method, characterized in that, The specific steps are as follows: First, the cell search process for NR cannot meet the number of SSBs required by the IRS auxiliary network. Different methods are used to expand the number of SSBs to match the number of base stations and IRS joint beams. The different SSB number expansion methods adopt the following approach: increasing the number of SSB number bits; reserving and dynamically scheduling the number of bits jointly carried by DMRS and PBCH; and supporting a maximum number of SSBs less than 2, which is a power of the number of bits to be scheduled. Alternatively, the following can be used: Explicit SSB extension period: Define the SSB extension period, and use the SSBs in multiple SSB periods for one beam scan; The base station determines and informs the terminal of at least one of the following: (1) the number of periods of the joint SSB; (2) the period in which the received SSB is in the extension period; Alternatively, the following can be used: Implicit SSB extension period: Define the SSB extension period, and use the SSBs in multiple SSB periods for one beam scan; The base station determines at least one of the following information: (1) the number of periods of the joint SSB; (2) which period of the transmitted SSB in the extension period, without explicitly informing the terminal, and by modifying the system message, the SSBs in the extension period are uniformly mapped to the PRACH resource. Then, the signaling content of the joint broadcast by the base station and IRS is updated according to the SSB number expansion method; Next, determine and implement the joint broadcast procedure between the base station and the IRS when the SSB is transmitted; The joint broadcast process is as follows: Step 1: Configure the correspondence between the IRS in the cell and the predefined direction of the base station beam, that is, which base station beam predefined directions each IRS and its reflection predefined direction are allowed to form a joint beam with; Step 2: Determine all possible serving beam sets for the cell, i.e., all possible beam forms formed by the base station beam predefined direction alone or by the base station beam predefined direction combined with the IRS reflection predefined direction; Step 3: Based on the determined number of SSBs and the signaling content that the base station and IRS need to broadcast together, establish the correspondence between SSBs and service beams. The correspondence requires that each service beam corresponds to at least one SSB. Step 4: Based on the correspondence, when the base station transmits a certain SSB, the base station and IRS implement the service beam corresponding to that SSB. When the base station transmits the SIB1 and OSI corresponding to that SSB, it also implements the service beam corresponding to that SSB, thereby realizing joint broadcasting by the base station and IRS. Finally, when performing cell search, the terminal detects SSBs on predefined frequency points according to the default period, parses the SSB number and other bearer information, and receives the SIB1 and OSI corresponding to the SSB.

2. The 6G intelligent reflecting surface assisted network cell search method of claim 1, wherein, When an IRS controlled by the base station is added, deleted, or rescheduled, the base station determines the number of SSBs required for one beam scan based on the new number of IRSs and the scheduling status.

3. The 6G intelligent surface-assisted network cell search method of claim 2, wherein, The number of SSBs is determined by at least one of the following: (1) the number of IRSs that are enabled, (2) the number of IRS reflection predefined directions, (3) the number of base station beam predefined directions, (4) the combination logic of base station beam predefined directions and IRS reflection predefined directions, and (5) the number of SSBs allocated to each base station IRS joint beam and base station beam.

4. The 6G intelligent surface-assisted network cell search method of claim 1, wherein, The increase in the number of SSB number bits to expand the number of SSBs corresponds to the following update signaling: Update the SSB map in the SIB1 / OSI information. This signaling is used to indicate the SSB scheduling status within a period. The SSB map consists of N bits. When M SSBs are called, M bits in the SSB map are 1 and the rest are 0, and N is always greater than M.

5. The 6G intelligent surface-assisted network cell search method of claim 1, wherein, The aforementioned explicit SSB extension cycle, which expands the number of SSBs, corresponds to updating at least one of the following signaling: Regarding the information: (1) Several cycles of SSB were combined; the signaling used included: (i) enumeration: the base station side and the terminal side predetermine the number of possible combinations and indicate which configuration is it through the SSB / SIB1 / OSI bearer field; (ii) direct indication: the SSB / SIB1 / OSI bearer information directly indicates the number of combinations; For the SSB received in information (2) within the extended period, the signaling used is direct indication. The relationship between the number of bits in the information field used for indication and the number of periods of the joint SSB is: the power of the number of bits of 2 is greater than or equal to the number of periods of the joint SSB.

6. The 6G intelligent reflecting surface assisted network cell search method of claim 1, wherein, The implicit SSB expansion cycle, which expands the number of SSBs, corresponds to the following update signaling: Based on the new number of SSBs, the base station updates the correspondence between each SSB and PRACH resources within the extension period, and updates the PRACH configuration signaling in each system message that needs to be sent to the terminal.

7. The 6G intelligent reflecting surface assisted network cell search method of claim 1, wherein, In the first step, a certain predefined reflection direction of the IRS can form a joint beam with multiple predefined beam directions of the base station beams; Multiple IRSs can also be configured to simultaneously form a joint beam with a base station beam predefined direction.

8. The 6G intelligent reflector-assisted network cell search method as described in claim 1, characterized in that, Regarding a) increasing the number of SSB number bits: The terminal determines the SSB with the strongest received signal strength within the reception period by measurement, and parses the SSB number and other SSB bearer information. The subsequent behavior has two options: Option 1: The terminal continues to receive the SIB1 and OSI corresponding to the SSB based on the information currently parsed by the SSB bearer; Option 2: After the terminal learns the base station's beam scanning period and SSB arrangement, it measures all SSBs within the SSB extension period to determine the strongest SSB. The terminal then continues to receive the SIB1 and OSI corresponding to the strongest SSB based on the information carried by that SSB. If the terminal is configured with multiple predefined receiving directions, the terminal operates in each predefined receiving direction by polling.

9. The 6G intelligent reflector-assisted network cell search method as described in claim 1, characterized in that, For b) explicit SSB extension period: The terminal determines the SSB with the strongest signal strength received within the reception period by measurement, and parses at least one of the following information: (1) how many SSBs were combined in total, (2) which period of the received SSB is in the extension period, (3) the SSB number, (4) and other SSB bearer information. The subsequent behavior has two options: Option 1: The terminal continues to receive the SIB1 and OSI corresponding to the SSB based on the information currently parsed by the SSB bearer; Option 2: After the terminal learns the base station's beam scanning period and SSB arrangement, it measures all SSBs within the SSB extension period to determine the strongest SSB. The terminal then continues to receive the SIB1 and OSI corresponding to the strongest SSB based on the information carried by that SSB. If the terminal is configured with multiple predefined receiving directions, the terminal operates in each predefined receiving direction by polling.

10. The 6G intelligent reflector-assisted network cell search method as described in claim 1, characterized in that, For c) Implicit SSB extended period: The terminal determines the SSB with the strongest signal strength received within the reception period by measurement, and parses (1) the SSB number (2) and other SSB bearer information. The terminal continues to receive the SIB1 and OSI corresponding to the SSB based on the currently parsed SSB bearer information.

11. A 6G intelligent reflective surface-assisted network cell search device, characterized in that, include: Transceiver, memory, processor, and computer program stored in the memory and executable on the processor; When the processor executes the program, it implements the steps of the cell search method according to any one of claims 1-10.

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