Communication methods and communication apparatuses

Abstract

A communication method, comprising: a first communication apparatus generating synchronization information for downlink synchronization, and sending the synchronization information to a second communication apparatus, wherein the synchronization information comprises N first synchronization sequences, the synchronization information further comprises N first CPs and / or N first GIs, the N first synchronization sequences correspond to the N first CPs on a one-to-one basis, the N first synchronization sequences correspond to the N first GIs on a one-to-one basis, the lengths of any two first CPs among the N first CPs are different, the lengths of any two first GIs among the N first GIs are different, and N is an integer greater than 1. Thus, when the second communication apparatus performs downlink synchronization on the basis of the synchronization information, the impact of a timing drift can be avoided, so that the downlink synchronization detection performance is improved. In addition, since the lengths of the CP and / or the GI corresponding to each sequence are different, the impact of a secondary peak of detection can be reduced so as to improve the downlink synchronization detection performance.

Description

Communication method and communication apparatus

[0001] The present application claims priority from the Chinese patent application No. 202410468883.2 filed on April 17, 2024, and entitled "Communication method and communication apparatus", the content of which is incorporated herein by reference in its entirety. TECHNICAL FIELD

[0002] Embodiments of the present application relate to the field of communication technology, and more particularly, to a communication method and a communication apparatus. BACKGROUND

[0003] Compared with terrestrial communication, non-terrestrial communication network (NTN) communication has the characteristics of large coverage area and flexible networking, and can achieve seamless global network coverage. NTN network is not only a supplement to the current ground network, but also can be regarded as an independent communication system that provides global high-speed network access for users. NTN communication includes using unmanned aerial vehicles, high-altitude platforms, or satellites and other devices for networking to provide data transmission, voice communication and other services for terminals.

[0004] In the satellite communication scenario, the downlink signal has low signal-to-noise ratio, and the timing drift caused by the high-speed movement of the satellite can cause the terminal to be unable to use the periodically repeated downlink synchronization sequence for joint detection, resulting in downlink synchronization failure. Therefore, how to realize downlink synchronization in the scenario of low signal-to-noise ratio and / or large timing drift becomes a problem to be solved. SUMMARY

[0005] The present application provides a communication method to realize downlink synchronization in the scenario of low signal-to-noise ratio and / or large timing drift.

[0006] In the first aspect, a communication method is provided, which can be executed by a first communication apparatus. In the case of no special description, the "first communication apparatus" in the present application can refer to the first communication apparatus itself (for example, an access network device), a component (for example, a processor, a chip, or a chip system, etc.) in the first communication apparatus, or a logic module or software capable of realizing all or part of the functions of the first communication apparatus.

[0007] The method can include: generating synchronization information, the synchronization information being used for downlink synchronization, the synchronization information including N first synchronization sequences; and transmitting the synchronization information, wherein the synchronization information further includes N first cyclic prefixes (CPs) and / or N first guard intervals (GIs), the N first synchronization sequences corresponding to the N first CPs one by one, the N first synchronization sequences corresponding to the N first GIs one by one, lengths of any two of the N first CPs being different, lengths of any two of the N first GIs being different, and the N being an integer greater than 1. The downlink synchronization includes downlink time domain and / or frequency domain synchronization.

[0008] Based on the above technical solution, the synchronization information transmitted by the first communication device includes synchronization sequences that are continuously transmitted for N times in a time domain unit (such as a time slot, a frame, or a subframe, etc.), and the lengths of the CPs and / or GIs corresponding to each sequence are different. When the second communication device performs downlink synchronization based on the synchronization information, the influence of timing drift can be avoided, and the downlink synchronization detection performance can be improved. In addition, because the lengths of the CPs and / or GIs corresponding to each sequence are different, the influence of detection sub-peak can be reduced, and the downlink synchronization detection performance can be further improved.

[0009] For example, because the synchronization sequences are continuously transmitted for N times in the time domain, the second communication device can receive N synchronization sequences for downlink synchronization at a time. Thus, the situation that multiple repeatedly transmitted synchronization broadcast blocks (SSBs) cannot be jointly detected (for example, multiple repeatedly transmitted primary synchronization signals (PSSs) cannot be jointly detected) due to large timing drift, causing downlink synchronization failure, can be avoided.

[0010] For another example, because the lengths of the CPs and / or GIs corresponding to each sequence are different, the influence of detection sub-peak can be reduced, and the downlink synchronization detection performance can be improved.

[0011] In combination with the first aspect, in some implementations of the first aspect, the method further includes: transmitting first indication information, the first indication information being used for indicating that the first synchronization sequences correspond to first CPs and / or first GIs.

[0012] Based on the technical solution, the first communication device can indicate, by using the first indication information, that the first synchronization sequence corresponds to the first CP, the first GI, or the first CP and the first GI. If the first synchronization sequence corresponds to the first CP, the first CP can be regarded as a repeatedly transmitted signal, which can improve the signal anti-multipath performance and ensure the signal frequency domain orthogonality. If the first synchronization sequence corresponds to the first GI, the transmission energy can be saved. For example, the GI part can transmit zero, and the time and / or frequency domain resources corresponding to the GI can not carry signals.

[0013] In addition, it should be noted that the first synchronization sequence corresponding to the first CP and / or the first GI can be predefined by a protocol, and does not need to be indicated by using the first indication information, thereby reducing the signaling overhead.

[0014] In a second aspect, a communication method is provided. The method can be executed by a second communication device. In the absence of special description, the "second communication device" in the present application can refer to the second communication device itself (for example, a terminal device), a component (for example, a processor, a chip, or a chip system) in the second communication device, or a logic module or software capable of realizing all or part of the functions of the second communication device.

[0015] The method can include: receiving synchronization information, the synchronization information being used for downlink synchronization, and the synchronization information including N first synchronization sequences; and performing downlink synchronization based on the synchronization information, wherein the synchronization information further includes N first CPs and / or N first GIs, the N first synchronization sequences correspond to the N first CPs one by one, the N first synchronization sequences correspond to the N first GIs one by one, lengths of any two first CPs in the N first CPs are different, lengths of any two first GIs in the N first GIs are different, and N is an integer greater than 1.

[0016] In combination with the second aspect, in some implementations of the second aspect, the method further includes: receiving first indication information, the first indication information being used for indicating that the first synchronization sequence corresponds to the first CP and / or the first GI.

[0017] In combination with the first aspect or the second aspect, in some implementations of the first aspect or the second aspect, the synchronization information further includes M second synchronization sequences, the M second synchronization sequences correspond to M second CPs respectively, and / or the M second synchronization sequences correspond to M second GI lengths respectively, lengths of any two second CPs in the M second CPs are different, lengths of any two second GIs in the M second GIs are different, and M is an integer greater than 1.

[0018] In some implementations of the first aspect or the second aspect, the synchronization information further comprises a third synchronization sequence, the third synchronization sequence corresponding to a third CP, and / or the third GI.

[0019] In some implementations of the first aspect or the second aspect, one or more second synchronization sequences are arranged between two first synchronization sequences in time domain, i.e., the first synchronization sequence and the second synchronization sequence are cross-arranged.

[0020] In some implementations of the first aspect or the second aspect, the sum of lengths of first CPs corresponding to the m2 first synchronization sequences starting from the m1 first synchronization sequence is different from the sum of lengths of first CPs corresponding to the m4 first synchronization sequences starting from the m3 first synchronization sequence, where m1, m2, and m4 are positive integers, and m3 is a positive integer greater than or equal to the sum of m1 and m2.

[0021] Based on the above technical solution, the situation that several adjacent CPs are added together in the same way can be avoided, and the detection performance can be further improved by reducing the influence of secondary peaks.

[0022] In some implementations of the first aspect or the second aspect, the N first CPs satisfy any one of the following conditions: the lengths of the N first CPs increase in order from small to large; or the lengths of the N first CPs decrease in order from large to small; or the ratio of lengths of two adjacent first CPs in the N first CPs is a preset value; or the value of N and the length of each CP in the lengths of the N first CPs satisfy a first corresponding relationship.

[0023] The N first GIs satisfy any one of the following conditions: the lengths of the N first GIs increase in order from small to large; or the lengths of the N first GIs decrease in order from large to small; or the ratio of lengths of two adjacent first GIs in the N first GIs is a preset value; or the value of N and the length of each GI in the lengths of the N first GIs satisfy a second corresponding relationship.

[0024] In some implementations of the first aspect or the second aspect, the first corresponding relationship can be represented in a table form, for example, the first corresponding relationship comprises:

[0025] In the second row of the table, L1 and L2 represent lengths of the two first CPs corresponding to the two first synchronization sequences respectively when N is equal to 2; in the third row of the table, L1, L2 and L3 represent lengths of the three first CPs corresponding to the three first synchronization sequences respectively when N is equal to 3.

[0026] In combination with the first aspect or the second aspect, in some implementations of the first aspect or the second aspect, the second correspondence can be represented in the form of a table, for example, the second correspondence includes:

[0027] In the second row of the table, L1 and L2 represent lengths of the two first CPs corresponding to the two first synchronization sequences respectively when N is equal to 2; in the third row of the table, L1, L2 and L3 represent lengths of the three first CPs corresponding to the three first synchronization sequences respectively when N is equal to 3.

[0028] In combination with the first aspect or the second aspect, in some implementations of the first aspect or the second aspect, the first communication device and the second communication device can also transmit data and / or control information, for example, the first communication device transmits data and / or control information, and the second communication device receives data and / or control information.

[0029] Optionally, the synchronization information is carried in a first time unit, and the data and / or control information is carried in a second time unit, a length of an ith CP in the second time unit is the same as a length of the ith CP in the first time unit, and / or a length of an ith GI in the second time unit is the same as a length of the ith GI in the first time unit, where i is an integer from 1 to N.

[0030] Based on the above technical solution, the lengths of the CP and / or the GI in the first time unit in which the synchronization sequence is repeatedly transmitted can be the same as the lengths of the CP and / or the GI in the second time unit in which data is transmitted, that is, the lengths of the CP and / or the GI between symbols in the time unit in which the synchronization sequence is transmitted and the time unit in which data is transmitted are the same (it can also be understood that the position of the synchronization sequence in the first time unit is replaced by data, but the lengths of the CP and / or the GI remain unchanged). Keeping the lengths of the CP and / or the GI in each time slot the same reduces the processing complexity.

[0031] Optionally, the synchronization information is carried in a first time unit, the data and / or control information is carried in a second time unit, a length of a jth CP in the second time unit is different from a length of the jth CP in the first time unit; and / or, a length of a jth GI in the second time unit is different from a length of the jth GI in the first time unit; where j is at least one of 1 to N.

[0032] Based on the above technical solution, the length of the CP and / or GI in the first time unit in which the synchronization sequence is repeatedly transmitted can be different from the length of the CP and / or GI in the second time unit in which data is transmitted, that is, the time unit in which the synchronization sequence is transmitted and the time unit in which data is transmitted can have different CP and / or GI lengths between symbols. The CP and / or GI length of the data part remains unchanged according to the existing design, which can be compatible with the existing terminal flexibility and can better resist multipath effects.

[0033] Optionally, the synchronization information is carried in a first time unit and a first frequency domain unit, the data and / or control information is carried in the first time unit and a second frequency domain unit, a length of a kth CP in the second frequency domain unit is the same as a length of the kth CP in the first frequency domain unit; and / or, a length of a kth GI in the second frequency domain unit is the same as a length of the kth GI in the first frequency domain unit; where k is from 1 to N.

[0034] Based on the above technical solution, for the time unit in which the synchronization sequence is transmitted, the CP and / or GI lengths of the same frequency domain resource and different frequency domain transmission data are the same, that is, the CP and / or GI lengths are consistent with the synchronization sequence, which can avoid inter-subcarrier interference or non-orthogonal interference.

[0035] In combination with the first aspect or the second aspect, in some implementations of the first aspect or the second aspect, the synchronization information is carried in a first time unit (slot or subframe or frame), a total CP length in the first time unit is the same as a total CP length in a second time unit; or, a total GI length in the first time unit is the same as a total GI length in the second time unit, where the second time unit is used to carry data.

[0036] In some implementations of the first aspect or the second aspect, the synchronization information is carried in first information, and the first information further includes at least one of the following: a system information block 1 (SIB1), a system information block 19 (SIB19), a master information block (MIB), or a physical broadcast channel.

[0037] In some implementations of the first aspect or the second aspect, the synchronization information is a synchronization signal and PBCH block (SS / PBCH block), and the SS / PBCH block includes N primary synchronization signals (PSSs), one secondary synchronization signal (SSS), and one physical broadcast channel (PBCH).

[0038] In some implementations of the first aspect or the second aspect, the SS / PBCH block occupies 14 orthogonal frequency division multiplexing (OFDM) symbols in the time domain, and the N PSSs occupy the 1st to 11th OFDM symbols, and the PSSs include 11 first synchronization sequences. For example, the PSSs are composed of 11 first synchronization sequences, and it can be understood that each first synchronization sequence corresponds to one PSS, and the SS / PBCH block includes 11 PSSs.

[0039] Based on the above technical solutions, the synchronization information can be an enhancement of the SS / PBCH block, that is, the SS / PBCH block includes multiple PSSs.

[0040] In a third aspect, a communication apparatus is provided, and the apparatus is configured to execute the method provided in the first aspect. Specifically, the communication apparatus can include units and / or modules for executing the method provided in any of the implementations of the first aspect, such as a processing unit and an obtaining unit.

[0041] In an implementation form, the transceiving unit can be a transceiver, or an input / output interface; and the processing unit can be at least one processor. Optionally, the transceiver can be a transceiving circuit. Optionally, the input / output interface can be an input / output circuit.

[0042] In another implementation form, the transceiving unit can be an input / output interface, an interface circuit, an output circuit, an input circuit, a pin or related circuitry on the chip, chip system or circuit; and the processing unit can be at least one processor, a processing circuit or a logic circuit.

[0043] In a fourth aspect, a communication apparatus is provided, which is configured to execute the method provided in the second aspect. Specifically, the communication apparatus can include units and / or modules for performing the method provided in the second aspect, such as a processing unit and an obtaining unit.

[0044] In an implementation form, the transceiving unit can be a transceiver, or an input / output interface; and the processing unit can be at least one processor. Optionally, the transceiver can be a transceiving circuit. Optionally, the input / output interface can be an input / output circuit.

[0045] In another implementation form, the transceiving unit can be an input / output interface, an interface circuit, an output circuit, an input circuit, a pin or related circuitry on the chip, chip system or circuit; and the processing unit can be at least one processor, a processing circuit or a logic circuit.

[0046] In a fifth aspect, a processor is provided, which is configured to execute the method provided in any of the implementation forms of the first and second aspects.

[0047] For the sending and obtaining / receiving operations of the processor, if no special description is provided, or if it does not contradict with the actual role or inherent logic in the related description, it can be understood as the processor outputting and receiving, inputting, etc., or as the sending and receiving operations performed by the radio frequency circuit and the antenna, which are not limited in the present application.

[0048] In a sixth aspect, a computer readable storage medium is provided, which stores program codes for execution by an apparatus, and the program codes include codes for executing the method provided in any of the implementation forms of the first and second aspects.

[0049] In a seventh aspect, a computer program product containing instructions which, when the computer program product is executed on a computer, cause the computer to execute the method provided in any of the implementation forms of the first and second aspects.

[0050] In an eighth aspect, a chip is provided, and the chip includes one or more processors and a communication interface. The processor reads a computer program or instructions stored on a memory through the communication interface, and executes the method provided in any implementation manner of the first aspect and the second aspect.

[0051] Optionally, as an implementation manner, the chip further includes a memory, and the memory stores the computer program or instructions. The processor is configured to execute the computer program or instructions stored on the memory, and when the computer program or instructions are executed, the processor is configured to execute the method provided in any implementation manner of the first aspect and the second aspect.

[0052] In a ninth aspect, a communication system is provided, and the communication system includes the communication device of the third aspect and the communication device of the fourth aspect. BRIEF DESCRIPTION OF DRAWINGS

[0053] FIG. 1 is a schematic diagram of a network architecture to which embodiments of the present application are applicable.

[0054] FIG. 2 is a schematic diagram of an open radio access network (O-RAN) architecture.

[0055] FIG. 3 is a schematic diagram of a satellite communication scenario to which embodiments of the present application are applicable.

[0056] FIG. 4 is a schematic diagram of an air to ground (ATG) communication scenario to which embodiments of the present application are applicable.

[0057] FIG. 5 is a schematic diagram of a transmissive satellite architecture.

[0058] FIG. 6 is a schematic diagram of a non-transmissive satellite architecture.

[0059] FIG. 7 is a schematic diagram of an SSB resource structure.

[0060] FIG. 8 is a schematic diagram of repeated transmission of an SSB period.

[0061] FIG. 9 is a schematic flowchart of a communication method provided by embodiments of the present application.

[0062] FIG. 10 is a schematic diagram of synchronization information provided by embodiments of the present application.

[0063] FIG. 11 is another schematic diagram of synchronization information provided by embodiments of the present application.

[0064] FIG. 12 is yet another schematic diagram of synchronization information provided by embodiments of the present application.

[0065] FIG. 13 is yet another schematic diagram of synchronization information provided by embodiments of the present application.

[0066] FIG. 14 is another schematic diagram of synchronization information according to an embodiment of the present application.

[0067] FIG. 15 is a schematic diagram of an SSB resource structure according to an embodiment of the present application.

[0068] FIG. 16 is a schematic diagram of a relationship between a synchronization information CP length and a data CP length according to an embodiment of the present application.

[0069] FIG. 17 is another schematic diagram of a relationship between a synchronization information CP length and a data CP length according to an embodiment of the present application.

[0070] FIG. 18 is a schematic block diagram of a communication apparatus according to an embodiment of the present application.

[0071] FIG. 19 is another schematic diagram of a communication apparatus according to an embodiment of the present application. DETAILED DESCRIPTION

[0072] In order to facilitate understanding of the embodiments of the present application, the following points are first explained.

[0073] First, in the present application, "for indicating" can include direct indication and indirect indication. When it is described that certain indication information is for indicating A, it can include that the indication information directly indicates A or indirectly indicates A, and does not mean that A must be carried in the indication information.

[0074] The information indicated by the indication information is referred to as to-be-indicated information. In the implementation process, there are many ways to indicate the to-be-indicated information, for example, but not limited to, the to-be-indicated information can be directly indicated, such as the to-be-indicated information itself or an index of the to-be-indicated information. The to-be-indicated information can also be indirectly indicated by indicating other information, where the other information and the to-be-indicated information have an association relationship. The to-be-indicated information can also be only indicated in part, and the other part of the to-be-indicated information is known or agreed in advance. For example, the indication of a specific information can also be achieved by means of the arrangement order of each information agreed in advance (for example, a protocol stipulates), thereby reducing the indication overhead to a certain extent. At the same time, the common part of each information can be identified and uniformly indicated, so as to reduce the indication overhead caused by separately indicating the same information.

[0075] Second, "at least one" in the present application refers to one or more, and "multiple" refers to two or more. In addition, in the embodiments of the present application, "first", "second", and various numbers (for example, "#1", "#2", etc.) are only for the convenience of description and do not limit the scope of the embodiments of the present application. The size of the serial number of each process below does not mean the order of execution, and the execution order of each process should be determined according to its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application. It should be understood that the objects thus described can be interchanged under appropriate circumstances, so as to be able to describe solutions other than the embodiments of the present application. In addition, in the embodiments of the present application, "S910" and the like are only for the convenience of description and are not limited to the order of execution steps.

[0076] Third, in the embodiments of the present application, "exemplary" or "for example" is used to indicate an example, illustration or description. Any embodiment or design scheme described as "exemplary" or "for example" in the present application should not be interpreted as more preferred or more advantageous than other embodiments or design schemes. Rather, the use of "exemplary" or "for example" is intended to present the relevant concept in a specific manner.

[0077] Fourth, in the embodiments of the present application, "saving" can refer to saving in one or more memories. The one or more memories can be separately arranged or integrated in the encoder or decoder, processor, or communication device. The one or more memories can be partially separately arranged and partially integrated in the decoder, processor, or communication device. The type of memory can be any form of storage medium, which is not limited in the present application.

[0078] Fifth, in the embodiments of the present application, "protocol" can refer to a standard protocol in the communication field, which can include new radio (NR) protocol and related protocols applied in future communication systems, which is not limited in the present application.

[0079] Sixth, in the embodiments of the present application, "of", "corresponding", "corresponding" and "associated" can be used interchangeably at times. It should be pointed out that when the distinction is not emphasized, the meanings expressed are consistent.

[0080] Seventh, in the embodiments of the present application, "in the case of", "when", "if" can be used interchangeably at times. It should be pointed out that when the distinction is not emphasized, the meanings expressed are consistent.

[0081] Eighth, the term "and / or" in this document is only a description of the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B can represent the following three cases: A exists alone, A and B exist together, and B exists alone. In addition, the character " / " in this document generally represents an "or" relationship between the associated objects before and after it.

[0082] Ninth, in the embodiments of the present application, the names of messages and devices are only examples, and the names of messages and devices in the present application are not limited in any way as long as they can realize the corresponding functions.

[0083] The technical solutions in the present application will be described below with reference to the accompanying drawings.

[0084] The technical solutions of the present application can be applied to satellite communication systems, high altitude platform (HAPS) communication, unmanned aerial vehicle, etc. non-terrestrial network (NTN) systems, such as integrated communication and navigation (IcaN) systems, global navigation satellite systems (GNSS), and ultra-dense low-orbit satellite communication systems. The satellite communication system can be integrated with the traditional mobile communication system. For example, the mobile communication system can be a fourth generation (4th generation, 4G) communication system (for example, a long term evolution (long term evolution, LTE) system), a worldwide microwave access (worldwide interoperability for microwave access, WiMAX) communication system, a fifth generation (5th generation, 5G) communication system (for example, a new radio (new radio, NR) system), and a future mobile communication system, etc.

[0085] FIG. 1 shows a schematic diagram of a communication system to which the embodiments of the present application can be applied. The communication system includes at least one network device and at least one terminal. The terminal includes a mobile terminal on the ground, an unmanned aerial vehicle, etc. When the network device or the terminal moves rapidly, the transceiver will move relatively, resulting in Doppler shift and sampling point timing drift. The network device and the terminal are sometimes referred to as communication apparatuses, for example, the network device in FIG. 1 can be understood as a communication apparatus with base station function, and the terminal can be understood as a communication apparatus with terminal function.

[0086] It should be understood that FIG. 1 is a simple illustration of one communication scenario to which the present application can be applied, taking the communication between an access network device and a terminal device, and the communication between the access network device and a core network device as examples, and does not limit the present application to other scenarios in which the present application can be applied. It should also be understood that FIG. 1 is a simplified schematic diagram for ease of understanding, and other network devices or other terminal devices can also be included in the communication system, which are not shown in FIG. 1.

[0087] The terminal in the embodiments of the present application can also be referred to as a terminal device, a user equipment (UE), a mobile station, a mobile terminal, etc. The terminal can be widely applied to 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, automatic driving, remote medical treatment, smart power grid, smart furniture, smart office, smart wear, smart transportation, smart city, etc. The terminal can be a mobile phone, a tablet computer, a computer with wireless transceiver function, a wearable device, a vehicle, a drone, a helicopter, an airplane, a ship, a robot, a mechanical arm, a smart home device, etc. The terminal is usually provided with a communication module, circuit or chip for executing corresponding communication functions, and is also configured with program instructions for executing corresponding communication functions.

[0088] The network device in the embodiments of the present application can also be referred to as an access network device, a radio access network (RAN) entity or an access node, etc., and constitutes a part of the communication system to help the terminal to realize wireless access. The communication system can include multiple network devices, which can be nodes of the same type or nodes of different types.

[0089] In a possible scenario, the network device can be a base station, an evolved NodeB (eNodeB), an access point (AP), a transmission reception point (TRP), a next generation NodeB (gNB), a base station in a future mobile communication system, or an access node in a WiFi system, etc. The network device can be a macro base station, a micro base station or an indoor station, a relay node or a donor node, or a radio controller. Optionally, the network device can also be a server, a wearable device, a vehicle or a vehicle-mounted device, etc. For example, the access network device in vehicle to everything (V2X) technology can be a road side unit (RSU).

[0090] In another possible scenario, a plurality of network devices cooperate to assist a terminal to implement wireless access, and different network devices respectively implement part of the functions of a base station. For example, the network device can be a central unit (CU), a distributed unit (DU), a CU-control plane (CP), a CU-user plane (UP), or a radio unit (RU), etc. The CU and the DU can be separately arranged, or can be included in the same network element, such as a baseband unit (BBU). The CU node and the DU node split the protocol layers of the gNB, and the functions of part of the protocol layers are placed in the CU for centralized control, and the remaining part or all of the protocol layers are distributed in the DU and controlled by the CU.

[0091] The CU is deployed with the radio resource control (RRC) layer, the packet data convergence protocol (PDCP) layer, and the service data adaptation protocol (SDAP) layer in the protocol stack; and the DU is deployed with the radio link control (RLC) layer, the media access control (MAC) layer, and the physical layer (PHY) in the protocol stack.

[0092] Among them, the CU has the processing capability of RRC, PDCP and SDAP. The DU has the processing capability of RLC, MAC and PHY.

[0093] It should be understood that the above division (or segmentation) of functions is only an example and does not limit the CU and DU of the present application. That is, there can be other ways of dividing the functions between the CU and the DU, and the embodiments of the present application do not limit this.

[0094] The functions of the CU can be implemented by one entity or by different entities. For example, the functions of the CU can be further divided, for example, by separating the control plane (CP) and the user plane (UP), i.e., the control plane of the CU (CU-CP) and the user plane of the CU (CU-UP). The CU-CP and the CU-UP can be implemented by different functional entities, and the CU-CP and the CU-UP can be coupled with the DU to jointly complete the functions of the network device. The control plane of the CU (CU-CP) can further include a further divided architecture, i.e., the CU-CP is further divided into CU-CP1 and CU-CP2. The CU-CP1 includes various radio resource management functions, and the CU-CP2 includes only the RRC function and the PDCP-control (C) function (i.e., the basic function of the control plane signaling at the PDCP layer).

[0095] In one possible way, the CU-CP is responsible for the control plane function, mainly including RRC and PDCP-C. The PDCP-C is mainly responsible for the encryption and decryption of the control plane data, integrity protection, data transmission, etc. The CU-UP is responsible for the user plane function, mainly including SDAP and PDCP-user (U). The SDAP is mainly responsible for processing the data of the core network and mapping the data flow to the bearer. The PDCP-U is mainly responsible for the encryption and decryption of the data plane, integrity protection, header compression, sequence number maintenance, data transmission, etc. The CU-CP and the CU-UP are connected through an E1 interface. The CU-CP represents the gNB and is connected to the core network through an Ng interface. The CU-CP is connected to the DU through an F1-C (control plane). The CU-UP is connected to the DU through an F1-U (user plane). Of course, there is also a possible implementation that the PDCP-C is also in the CU-UP.

[0096] The CU (or CU-CP and CU-UP), DU or RU can also have different names in different systems, but those skilled in the art can understand their meanings. For example, the radio access network can also be an open radio access network (O-RAN) architecture. In the O-RAN system, the CU can also be referred to as an open CU (O-CU), the DU can also be referred to as an open DU (O-DU), the CU-CP can also be referred to as an open CU-CP (O-CU-CP), the CU-UP can also be referred to as an open CU-UP (O-CU-UP), and the RU can also be referred to as an O-RU. Any of the CUs (or CU-CP, CU-UP), DUs and RUs in this application can be implemented by a software module, a hardware module, or a combination of a software module and a hardware module.

[0097] For ease of understanding, the O-RAN architecture designed by the present application is briefly introduced in conjunction with FIG. 2. As can be seen from FIG. 2, the O-RAN architecture includes a first network element, a second network element, a third network element, an O-eNB, an O-CU-CP, an O-CU-UP, an O-DU, an O-RU and an O-cloud.

[0098] The above network elements (also referred to as nodes) can be connected to each other. For example, the first network element is connected to the O-cloud through an O2 interface, the first network element is connected to the third network element, the O-eNB, the O-CU-CP, the O-CU-UP, the O-DU and the O-RU through an O1 interface, the first network element is connected to the O-RU through an open front-haul M-Plane interface, the O-DU is connected to the O-RU through an open front-haul M-Plane interface and an open front-haul C / U / S-Plane interface, the third network element is connected to the O-eNB, the O-CU-CP, the O-CU-UP and the O-DU through an E2 interface, the O-CU-CP is connected to the O-DU through an F1-c interface, the O-CU-UP is connected to the O-DU through an F1-u interface, and the O-CU-CP is connected to the O-CU-UP through an E1 interface. For specific description of the interfaces shown in FIG. 2, please refer to the existing standard, which will not be described here.

[0099] As a possible example, the first network element can be a service management and orchestration framework (SMO), or a network element similar in function to the SMO, which is not limited.

[0100] One possible example, the second network unit can be a Non-RT RIC, or a network unit similar in function to a Non-RT RIC, without limitation.

[0101] One possible example, the third network unit can be a Near-RT RIC, or a network unit similar in function to a Near-RT RIC, without limitation.

[0102] O-RAN aims to realize an intelligent and open access network. The main feature of the O-RAN architecture is the separation of software and hardware, which realizes the virtualization of network functions and the standardization of hardware. In addition, O-RAN also introduces artificial intelligence (AI).

[0103] In the ORAN system, the CU can also be referred to as an O-CU (open CU), the DU can also be referred to as an O-DU, the CU-CP can also be referred to as an O-CU-CP, the CU-UP can also be referred to as an O-CU-UP, and the RU can also be referred to as an O-RU. In different systems, the CU (or CU-CP and CU-UP), DU or RU can also have different names, but those skilled in the art can understand their meanings. Any one of the CU (or CU-CP, CU-UP), DU and RU in this application can be realized by a software module, a hardware module, or a combination of a software module and a hardware module.

[0104] The communication system in the embodiments of the present application can also include a core network device, i.e., a device in the core network (CN) that provides service support for the terminal. At present, some examples of core network devices are: access and mobility management function (AMF) entities, session management function (SMF) entities, user plane function (UPF) entities, and the like, which are not listed one by one here. Among them, the AMF entity can be responsible for access management and mobility management of the terminal; the SMF entity can be responsible for session management, such as session establishment of a user; and the UPF entity can be a functional entity of the user plane, mainly responsible for connecting external networks. It should be noted that the entity in the present application can also be referred to as a network element or a functional entity, for example, the AMF entity can also be referred to as an AMF network element or an AMF functional entity, and for example, the SMF entity can also be referred to as an SMF network element or an SMF functional entity, and the like.

[0105] It should be understood that the above naming is only defined for the convenience of distinguishing different functions, and should not constitute any limitation on the present application. The present application does not exclude the possibility of using other names in 5G networks and future other networks. For example, in future mobile communication networks, part or all of the above network elements can continue to use the terms in 5G, or other names, etc.

[0106] As can be seen from the above, in the communication scenario shown in FIG. 1, when the network device or the terminal moves quickly, the transmitting end and the receiving end will move relatively, resulting in Doppler shift and sampling point timing drift.

[0107] As a possible implementation manner, if the network device and the terminal in FIG. 1 are devices in a satellite communication system, the above-mentioned relative motion of the transmitting end and the receiving end, the Doppler shift and the sampling point timing drift may occur. Therefore, the present application can also be applied to a satellite communication scenario. In order to facilitate understanding, the satellite communication scenario to which the present application scheme is applicable will be briefly introduced in combination with FIG. 3.

[0108] As shown in FIG. 3, the network device in the satellite communication scenario includes a satellite device and a gateway. The terminal includes an Internet of Things terminal, and can also be a terminal of other forms and performances, for example, a mobile phone terminal, a high-altitude aircraft, etc., which are not limited here. The link between the satellite and the user terminal is called a service link, and the link between the satellite and the gateway is called a feeder link. It should be understood that the satellite communication scenario shown in FIG. 3 is only an example, and does not constitute any limitation on the protection scope of the present application. For example, multiple satellites can be included in the satellite communication scenario, that is, the present application can be applied to a multi-satellite communication scenario.

[0109] As another possible implementation manner, if the network device and the terminal in FIG. 1 are devices in an air to ground (ATG) communication scenario, the above-mentioned relative motion of the transmitting end and the receiving end, the Doppler shift and the sampling point timing drift may occur. Therefore, the present application can also be applied to an ATG communication scenario. In order to facilitate understanding, the ATG communication scenario to which the present application scheme is applicable will be briefly introduced in combination with FIG. 4.

[0110] As shown in FIG. 4, the network device includes a ground base station, and the terminal includes a high-altitude aircraft, an on-board handheld terminal, etc. In this scenario, there is high-speed relative motion between the transmitting end and the receiving end.

[0111] It should be noted that the above-mentioned FIG. 3 and FIG. 4 are only examples, and do not constitute any limitation on the protection scope of the present application. The technical scheme provided by the present application can also be applied to other scenarios in which the transmitting end and the receiving end can move relatively, which will not be illustrated one by one here.

[0112] For the convenience of understanding the embodiments of the present application, some basic concepts involved in the present application are briefly described.

[0113] 1. Non-terrestrial networks (NTN): Compared with terrestrial communication, NTN communication has the characteristics of large coverage area, flexible networking, etc., and can achieve seamless global network coverage. NTN network is not only a supplement to the current ground network, but also can be regarded as an independent communication system that provides global high-speed network access for users. At present, research institutes, communication organizations and communication companies around the world are participating in the research of NTN communication technology and standard formulation, trying to build a unified communication network of sky, space and ground.

[0114] NTN communication includes networking by using unmanned aerial vehicles, high-altitude platforms or satellites, etc., to provide data transmission, voice communication and other services for UEs. The high-altitude platform device is generally 8-50 km away from the ground. According to the orbital height of the satellite, the satellite communication system can be divided into three types: geostationary earth orbit (GEO) satellite communication system, also known as synchronous orbit satellite system; medium earth orbit (MEO) satellite communication system and low earth orbit (LEO) satellite communication system. The orbital height of GEO satellite is 35786 km. Its main advantage is that it can remain relatively stationary on the ground and provide a large coverage area. However, GEO satellite communication also has obvious disadvantages:

[0115] 1) The GEO satellite orbit is far away from the earth, and the free space propagation loss is large, which causes the communication link budget to be tight. In order to increase the transmission / reception gain, a large-diameter antenna needs to be provided for the satellite;

[0116] 2) The communication transmission delay is large, which can reach about 500 ms round-trip delay, and cannot meet the demand of low-delay services;

[0117] 3) The GEO orbit resources are relatively tight, the launch cost is high, and the coverage cannot be provided for the two polar regions of the earth.

[0118] The orbit height of MEO satellite is in the range of 2000-35786 km, which has the advantage of global coverage with relatively small number of satellites, but the orbit height is higher than LEO, and the communication transmission delay is still larger than LEO. In view of the advantages and disadvantages of MEO satellite communication, MEO satellite is mainly applied to positioning and navigation. The orbit height of LEO satellite is in the range of 300-2000 km, and LEO satellite has the advantages of smaller data propagation delay, smaller transmission loss and lower launch cost than MEO and GEO. Therefore, LEO satellite communication has been paid more and more attention in recent years.

[0119] In the satellite communication scenario, the downlink signal has low signal-to-noise ratio, and the timing drift caused by the high-speed movement of the satellite causes the terminal to be unable to use the periodically repeated downlink synchronization sequence for joint detection.

[0120] 2, Satellite working mode: including transparent mode and non-transparent mode. Among them, the transparent mode is that the signal only performs frequency conversion, signal amplification and other processes on the satellite, and the satellite is transparent to the signal; the non-transparent mode is that the satellite has the function of the base station in the signal transmission process, and the UE can send signals to the 5G core network (CN) through the satellite.

[0121] Optionally, the transparent is also called as the pipe-bending forwarding transmission, that is, the signal only performs frequency conversion, signal amplification and other processes on the satellite, and the satellite is transparent to the signal, which is as if it does not exist. The non-transparent is also called as the regenerative (on-satellite access or processing) transmission, that is, the satellite has part or all of the base station function (such as the satellite corresponding to the complete base station or DU).

[0122] As an example but not limitation, the satellite communication system includes a transparent satellite architecture and a non-transparent satellite architecture. In the transparent satellite architecture, the satellite works in the transparent mode, and in the non-transparent satellite architecture, the satellite works in the non-transparent mode. For ease of understanding, the transparent satellite architecture and the non-transparent satellite architecture are briefly introduced in combination with FIG. 5 and FIG. 6. As shown in FIG. 5, the signal passes through the satellite and the NTN gateway in the transmission process of the UE and the gNB, but the signal only performs frequency conversion, signal amplification and other processes on the satellite, and the satellite is transparent to the signal. As shown in FIG. 5, the satellite and the NTN gateway in the transparent satellite architecture are equivalent to the remote radio unit (RRU). In addition, as shown in FIG. 6, the satellite has the function of the base station in the signal transmission process, and the UE can send signals to the 5G CN through the satellite.

[0123] 3、Synchronization signal and PBCH block (SS / PBCH block): The SS / PBCH block can be referred to as SSB. Specifically, as shown in FIG. 7, FIG. 7 is a schematic diagram of an SSB resource structure. As shown in FIG. 7, one SSB is composed of one primary synchronization signal (PSS) of an orthogonal frequency division multiplexing (OFDM) symbol, one secondary synchronization signal (SSS) of a symbol, and two symbols of a physical broadcast channel (PBCH). The positions of the PSS, the SSS, and the PBCH in the synchronization signal block are shown in FIG. 7, where the sequence length of the PSS / SSS is 127, and the PSS / SSS occupies 127 subcarriers (SCs) in the frequency domain, and the PBCH occupies 288 subcarriers in the frequency domain.

[0124] Exemplarily, the SSB is repeatedly transmitted in a time domain period, and the period of the SSB can be set to 5 milliseconds (ms), 10 ms, 20 ms, 40 ms, 80 ms, or 160 ms, and the like, and is generally set to a 20 ms period by default. As shown in FIG. 8, the SSB is repeated with a period of 20 ms. Wherein a plurality of SSBs form one synchronization broadcast block set, and four SSBs form one synchronization broadcast block set in FIG. 8 as an example. Each synchronization broadcast block set is completed in 5 ms, and each SSB in one 5 ms synchronization broadcast block corresponds to one beam direction, and the beam directions of the SSBs in one synchronization broadcast block set cover the entire cell. Each SSB contains the transmission of the PSS, the SSS, and the PBCH.

[0125] 4、PSS detection: When the terminal is powered on and enters the communication system, the terminal searches for the PSS, and the UE can be synchronized to the PSS period after detecting the PSS. As an example, when the terminal detects a single PSS, when the signal-to-noise ratio (SNR) ≥-4.8 decibels (dB), the PSS detection success rate ≥0.9 (considering the influence of channel fading, frequency offset, phase noise, noise, and the like).

[0126] The above briefly introduces the scenario to which the communication method provided by the embodiments of the present application can be applied, and introduces the basic concepts that can be involved in the embodiments of the present application, and introduces PSS detection in the basic concepts. It should be noted that in the NTN communication scenario, especially in the handset-direct satellite scenario, the signal-to-noise ratio of the received signal at the receiving end is lower. As an example, the downlink budget of the handset-direct satellite can be lower than -10 dB, and the PSS detection performance of a single SSB cannot meet the low signal-to-noise ratio requirement. In addition, another typical difference between the LEO satellite communication scenario and the ground communication is that the timing drift rate caused by the high-speed movement of the satellite is large, for example, up to 89 samples / s. When the SSB repetition period is 20 ms, the time length of 5 repetitions causes a drift of 7.12 samples, and at this time, due to the large timing drift, the SSBs (for example, the PSSs) transmitted multiple times cannot be jointly detected, causing downlink synchronization failure.

[0127] In summary, in the NTN scenario, the signal-to-noise ratio is low and the timing drift is large, and the periodically repeated PSS cannot be jointly detected, which can cause downlink synchronization failure.

[0128] The present application provides a communication method to achieve downlink synchronization in a scenario with low signal-to-noise ratio and / or large timing drift.

[0129] The technical solutions provided by the present application will be described in detail below with reference to the drawings. The embodiments of the present application can be applied in multiple different scenarios, including the scenario shown in FIG. 1, but are not limited to this scenario. For example, it can also be applied in 4G, 5G or future communication systems.

[0130] It should be understood that the embodiments shown below do not particularly limit the specific structure of the execution subject of the method provided by the embodiments of the present application, as long as the execution subject can communicate according to the method provided by the embodiments of the present application by running the program in which the code of the method provided by the embodiments of the present application is recorded. For example, the execution subject of the method provided by the embodiments of the present application can be a receiving end device or a sending end device, or a functional module in the receiving end device or the sending end device that can call and execute the program.

[0131] In the following, without loss of generality, the communication method provided by the embodiments of the present application is described in detail by taking the interaction between a first communication device and a second communication device as an example. The first communication device can be an access network device (or a CU or a DU in the access network device), or a network device in O-RAN (or a CU (such as O-CU (open CU)) in O-RAN or a DU (such as O-DU (open DU)) in O-RAN. The second communication device can be a terminal device, or a chip, circuit, etc. inside the terminal device. For ease of description, the first device is taken as a terminal device in the following description.

[0132] FIG. 9 is a schematic flowchart of a communication method provided by the present application, comprising the following steps:

[0133] S910, the first communication device generates synchronization information.

[0134] Specifically, the synchronization information is used for downlink synchronization. The downlink synchronization includes downlink time domain and / or frequency domain synchronization.

[0135] Optionally, the synchronization information includes but is not limited to a synchronization signal block. The synchronization signal block involved in this embodiment can be an enhancement of the SSB shown in FIG. 7, which can be referred to as an enhanced SSB.

[0136] Exemplarily, the synchronization information includes N first synchronization sequences, and further includes N first CPs and / or N first GIs. The N first synchronization sequences correspond to the N first CPs respectively, and / or the N first synchronization sequences correspond to the N first GIs respectively. For example, if the synchronization information includes N first CPs, the N first synchronization sequences correspond to the N first CPs one by one, and the first CP corresponding to each first synchronization sequence is located before the first synchronization sequence in the time domain; if the synchronization information includes N first GIs, the N first synchronization sequences correspond to the N first GIs one by one, and the first GI corresponding to each first synchronization sequence is located before the first synchronization sequence in the time domain; if the synchronization information includes N first CPs and N first GIs, the N first synchronization sequences correspond to the N first CPs and N first GIs one by one, and the first CP and the first GI corresponding to each first synchronization sequence are located before the first synchronization sequence in the time domain.

[0137] Wherein, the lengths of the N first CPs are different, that is, the lengths of any two first CPs in the N first CPs are different. Similarly, the lengths of the N first GIs are different, that is, the lengths of any two first GIs in the N first GIs are different. N is an integer greater than 1.

[0138] Optionally, in this embodiment, the lengths of at least two first CPs in the N first CPs are different, and the lengths of at least two first GIs in the N first GIs are different. For example, N is an integer greater than 3, the lengths of at least two first CPs in the N first CPs are different, and the lengths of at least two first GIs in the N first GIs are different.

[0139] From the above, in this embodiment, the N first synchronization sequences included in the synchronization information can correspond to N first CPs respectively; or, the N first synchronization sequences can correspond to N first GIs respectively; or, the N first synchronization sequences can correspond to N first CPs and N first GIs respectively. For the convenience of understanding, the correspondence between the synchronization sequence and the CP, and the correspondence between the synchronization sequence and the GI are described respectively below. For the case of the correspondence between the synchronization sequence and the CP and the GI, reference can be made to the following description (e.g., replacing the CP with the CP and the GI), and no longer be described in detail.

[0140] As a possible implementation, the synchronization information includes N first synchronization sequences, and the N first synchronization sequences correspond to N first CPs with different lengths.

[0141] In this implementation, it can be understood that the first synchronization sequence is repeated N times continuously in the time domain, and the CP length corresponding to each first synchronization sequence is different. As shown in FIG. 10, the synchronization sequence is repeated N times continuously in the time domain, and the CP length corresponding to each synchronization sequence is different, for example, the CP with the length of L1 corresponds to the first first synchronization sequence, the CP with the length of L2 corresponds to the second first synchronization sequence, and so on, where L1≠L2≠L3……≠LN.

[0142] Optionally, in order to reduce the influence of the secondary peak on the downlink synchronization detection performance, it is necessary to avoid the case that the lengths of some adjacent CPs are the same. For example, the sum of the lengths of the first CPs corresponding to the continuous m2 first synchronization sequences starting from the m1th first synchronization sequence is different from the sum of the lengths of the first CPs corresponding to the continuous m4 first synchronization sequences starting from the m3th first synchronization sequence, where m1, m2, and m4 are positive integers, and m3 is a positive integer greater than or equal to the sum of m1 and m2. For example, m2 is equal to m4, and as shown in FIG. 10, L1+L2≠L5+L6, or L1+L2+L3≠L5+L6+L7 is avoided.

[0143] As an example but not limitation, the lengths of the N first CPs corresponding to the N first synchronization sequences satisfy any one of the following relationships:

[0144] The lengths of the N first CPs increase in order from small to large (or in order from small to large) (for example, L1<L2<L3……<LN shown in FIG. 10); or,

[0145] The lengths of the N first CPs decrease in order from large to small (or in order from large to small) (for example, L1>L2>L3……>LN shown in FIG. 10); or,

[0146] The lengths of the N first CPs are disordered, and it is only required that the lengths of the CPs are different; or,

[0147] a ratio of lengths of two adjacent first CPs in the N first CPs is a preset value (e.g., L1:L2:L3…:LN=1:2:3…:N shown in FIG. 10); or

[0148] N is a value and each CP length in the N first CP lengths satisfies a first corresponding relationship. The first corresponding relationship can be referred to as a first mapping relationship.

[0149] Optionally, the first corresponding relationship can be in a form of a table. For example, the first corresponding relationship includes:

[0150] Table 1

[0151] In the table, L1 and L2 in the second row represent lengths of two first CPs corresponding to two first synchronization sequences respectively when N is equal to 2; L1, L2 and L3 in the third row represent lengths of three first CPs corresponding to three first synchronization sequences respectively when N is equal to 3. It should be understood that when N has different values, the lengths of the first CPs are also related to values of inverse fast Fourier transformation (IFFT) and subcarrier spacing (SCS).

[0152] Exemplarily, a synchronization sequence is repeated in time domain for N times, and lengths of N CPs corresponding to N synchronization sequences are exemplified as shown in Table 1a.

[0153] Table 1a

[0154] Optionally, the length of the CP can be 0. It can be understood that the length of the CP corresponding to the synchronization sequence #1 is 0, that is, no CP is placed in front of the synchronization sequence #1; or the length of the CP being 0 can be understood as that a previous synchronization sequence (e.g., synchronization sequence #2) of the synchronization sequence #1 can be regarded as the CP of the synchronization sequence #1 (because the synchronization sequences are repeated in time domain, the synchronization sequence #2 is the same as the synchronization sequence #1), that is, the length of the CP of the synchronization sequence #1 is the length of the synchronization sequence #2.

[0155] In Table 1a, the time unit of the length of the CP is a sampling interval, for example, the sampling interval is equal to 1 / (IFFT*SCS). Optionally, the time unit of the length of the CP can use other time units, for example, a time unit represented by Tc, Tc=1 / (Δf max ·N f ), Δf max = 480 × 10 3 Hz, N f= 4096. For example, Ts represents a time unit, Ts = 1 / (Δf ref · N f,ref ), Δf ref = 15·10 3 Hz, where Ts / Tc = 64. For example, the sampling interval time unit of the CP length used in Table 1a can be converted to Tc or Ts. For example, if the CP length is expressed by Tc or Ts, the CP length corresponding to the 15 KHz subcarrier spacing can be converted to the CP length corresponding to other subcarrier spacing by multiplying 2^ -u, where μ is related to the subcarrier spacing, i.e., the subcarrier spacing is 2 μ · 15 kHz. For example, when the CP length corresponding to the 15 KHz subcarrier spacing expressed by Tc time unit is 384*64*Tc, the CP length corresponding to other subcarrier spacing is 384*64*Tc*2^ -u, such as the CP length corresponding to the 30 KHz subcarrier spacing is 384*64*Tc*2^ -1 = 384*32*Tc. The conversion of the CP length described above is also applicable to the conversion of the GI length described below.

[0156] For example, the CP repeated 14 times is 0, 76, 26, 24, 22, 20, 18, 16, 14, 12, 10, 8, 6, 4. For example, the CP repeated 13 times is 0, 62, 26, 24, 22, 20, 18, 16, 14, 12, 10, 8, 6. The position of the CP 0 can also be changed to other positions. For example, the CP repeated 14 times is 76, 26, 24, 22, 20, 18, 16, 14, 12, 10, 8, 6, 4, 0. For example, the CP repeated 13 times is 62, 26, 24, 22, 20, 18, 16, 14, 12, 10, 8, 6, 0. More examples of the number of repetitions are shown in Table 1b.

[0157] Table 1b

[0158] It should be understood that the above Table 1a and Table 1b are only examples and do not constitute any limitation on the scope of protection of the present application. As can be seen from the above Table 1a and Table 1b, the length of the N CPs corresponding to the N synchronization sequences is exemplified under the constraint of a certain number of inverse fast Fourier transformation (IFFT) points and subcarrier spacing (SCS). For other IFFT point numbers and SCS values, the corresponding CP length can be converted based on a reference, where the reference can be the value shown in the above table.

[0159] For example, the CP length corresponding to other IFFT length and SCS satisfies the following relationship:

[0160] CP_length_new=(IFFT_new*SCS_new) / (IFFT_base*SCS_base) / (SCS_new / SCS_base)*CP_length,

[0161] wherein IFFT_base can be the length 256 corresponding to the data in the table, SCS_base can be the subcarrier spacing 15KHz corresponding to the table, IFFT_new represents the IFFT point number to be used (or the corresponding IFFT point number to be converted to), SCS_new represents the subcarrier spacing to be used (or the corresponding subcarrier spacing to be converted to), CP_length is the CP length in the table, and CP_length_new represents the CP length to be used (or the corresponding CP length to be converted to).

[0162] It should be noted that the above relationship is only an example and does not constitute any limitation on the protection scope of the present application. Other ways of determining the updated value based on the reference value are also within the protection scope of the present application. For example, the above relationship can also be expressed as: (IFFT_new*SCS_new) / (IFFT_base*SCS_base) / (2^μnew / 2^μold)*CP_length,

[0163] wherein 2^μnew is related to the subcarrier spacing, and SCS=15KHz*2^μnew.

[0164] For example, for IFFT_new=2048, SCS=120KHz, and the reference value is as described in Table 1, for the synchronization sequence time domain repetition number being 4, the calculated CP length to be used after conversion is [22 20 18 14]*8=[176 160 144 112].

[0165] Further, in this implementation manner, the synchronization information can further include M second synchronization sequences, the M second synchronization sequences correspond to M second CPs respectively, the lengths of the M second CPs are different from each other, and M is an integer greater than 1.

[0166] Exemplarily, as shown in FIG. 11, when the multiple synchronization sequences are repeated in time domain consecutively (such as synchronization sequence 1 and synchronization sequence 2 are repeated in time domain consecutively), the synchronization sequence 1 is repeated in time domain for N times (such as N=3 shown in FIG. 11), and the CP length corresponding to each synchronization sequence 1 is different, such as the CP length L1≠L2≠L3 shown in FIG. 11; the synchronization sequence 2 is repeated in time domain for M times (such as M=3 shown in FIG. 11), and the CP length corresponding to each synchronization sequence 2 is different, such as the CP length L4≠L5≠L6 shown in FIG. 11.

[0167] Optionally, when the multiple synchronization sequences are repeated in time domain consecutively, the length of the CP corresponding to different synchronization sequences can be different. For example, in the scenario shown in FIG. 11, L1≠L2≠L3≠L4≠L5≠L6.

[0168] Optionally, when the multiple synchronization sequences are repeated in time domain consecutively, the length of the CP corresponding to different synchronization sequences can be the same. For example, in the scenario shown in FIG. 11, L1≠L2≠L3, but L1=L6, L2=L5, and L3=L4.

[0169] As another possible implementation, the synchronization information includes N first synchronization sequences, and the length of the N first GIs corresponding to the N first synchronization sequences is different.

[0170] In this implementation, it can be understood that the first synchronization sequence is repeated in time domain for N times, and the length of the GI corresponding to each first synchronization sequence is different. As shown in FIG. 12, the synchronization sequence is repeated in time domain for N times, and the length of the GI corresponding to each synchronization sequence is different, such as L1≠L2≠L3……≠LN shown in FIG. 12.

[0171] Optionally, in order to reduce the influence of the secondary peak and improve the performance of downlink synchronization detection, the length of the first GI corresponding to the first synchronization sequence should be avoided to be the same when the length of the first GI corresponding to the first synchronization sequence is added. For example, the length of the first GI corresponding to the first synchronization sequence m1 to the first synchronization sequence m1+m2 is different from the length of the first GI corresponding to the first synchronization sequence m3 to the first synchronization sequence m3+m4, where m1, m2, and m4 are positive integers, and m3 is a positive integer greater than or equal to the sum of m1 and m2. For example, as shown in FIG. 12, L1+L2≠L5+L6, or L1+L2+L3≠L5+L6+L7 is avoided.

[0172] As an example but not limitation, the length of the N first GIs corresponding to the N first synchronization sequences satisfies any one of the following relationships:

[0173] The length of the N first GIs increases from small to large (or is sorted from small to large) (for example, L1<L2<L3……<LN shown in FIG. 12); or,

[0174] The lengths of the N first GIs decrease from large to small in turn (or are sorted from large to small) (for example, L1>L2>L3>…>LN as shown in FIG. 12); or

[0175] The lengths of the N first GIs are disordered, and it is only required that the lengths of the respective GIs are different; or

[0176] The ratio of the lengths of any two adjacent first GIs in the N first GIs is a preset value (for example, L1:L2:L3:…:LN=1:2:3:…:N as shown in FIG. 12); or

[0177] N is a value and each of the lengths of the N first GIs satisfies a second corresponding relationship. The first corresponding relationship can be referred to as a second mapping relationship.

[0178] Optionally, the second corresponding relationship can be in the form of a table. For example, the second corresponding relationship includes:

[0179] Table 2

[0180] In the table, L1’ and L2’ in the second row represent the lengths of two first GIs corresponding to two first synchronization sequences respectively in the case that the IFFT value X, the SCS value Y, and N equal to 2. L1’, L2’, and L3’ in the third row represent the lengths of three first GIs corresponding to three first synchronization sequences respectively in the case that the IFFT value X, the SCS value Y, and N equal to 3.

[0181] Exemplarily, the synchronization sequence is repeated N times in the time domain, and the lengths of the N GIs corresponding to the N synchronization sequences are exemplified as shown in Table 1a. The difference is that the lengths of the N first GIs are replaced by the lengths of the N first GIs in Table 1a, and the details are not repeated here.

[0182] Optionally, the GI can be 0. As shown in Table 1b, the difference is that the lengths of the N first GIs are replaced by the lengths of the N first GIs in Table 1b, and the details are not repeated here.

[0183] It should be understood that Table 1a and Table 1b are only examples and do not constitute any limitation on the protection scope of the present application. As shown in Table 1a and Table 1b, the lengths of the N GIs corresponding to the N synchronization sequences are exemplified under the limitation of a certain IFFT point number and subcarrier spacing (SCS). For other IFFT point numbers and SCS values, the corresponding GI lengths can be converted based on a reference, where the reference can be the values shown in the table.

[0184] For example, the GI length corresponding to other IFFT length and SCS satisfies the following relationship: GI_length_new = (IFFT_new*SCS_new) / (IFFT_base*SCS_base) / (SCS_new / SCS_base)*GI_length,

[0185] wherein, IFFT_base can be the length 256 corresponding to the data in the table, SCS_base can be the subcarrier spacing 15KHz corresponding to the table, IFFT_new represents the IFFT point number to be used (or the corresponding IFFT point number to be converted to), SCS_new represents the subcarrier spacing to be used (or the corresponding subcarrier spacing to be converted to), GI_length is the GI length in the table, and GI_length_new represents the GI length to be used (or the corresponding GI length to be converted to).

[0186] It should be noted that the above relationship is only an example and does not constitute any limitation on the protection scope of the present application. Other ways of determining the updated value based on the reference value are also within the protection scope of the present application. For example, the above relationship can also be expressed as: (IFFT_new*SCS_new) / (IFFT_base*SCS_base) / (2^μnew / 2^μold)*GI_length,

[0187] wherein, 2^μnew is related to the subcarrier spacing, and SCS=15KHz*2^μnew.

[0188] For example, for IFFT_new=2048, SCS=120KHz, and the reference value is as described in Table 1, for the synchronization sequence time domain repetition number being 4, the calculated GI length to be used after conversion is [22 20 18 14]*8=[176 160 144 112].

[0189] Further, in this implementation manner, the synchronization information can further include M second synchronization sequences, the M second synchronization sequences correspond to M second GIs respectively, the M second GIs have different lengths, and M is an integer greater than 1.

[0190] For example, as shown in FIG. 13, when the multiple synchronization sequences are repeated continuously in time domain (for example, synchronization sequence 1 and synchronization sequence 2 are repeated continuously in time domain), the synchronization sequence 1 is repeated N times (for example, N=3 in FIG. 13) in time domain, and the GI lengths corresponding to each synchronization sequence 1 are different, for example, the GI lengths L1≠L2≠L3 shown in FIG. 11; the synchronization sequence 2 is repeated M times (for example, M=3 in FIG. 13) in time domain, and the GI lengths corresponding to each synchronization sequence 2 are different, for example, the GI lengths L4≠L5≠L6 shown in FIG. 11.

[0191] Optionally, when the multiple synchronization sequences are repeated in time domain consecutively, the lengths of the GIs corresponding to different synchronization sequences can be different. For example, in the scenario shown in FIG. 11, L1≠L2≠L3≠L4≠L5≠L6.

[0192] Optionally, when the multiple synchronization sequences are repeated in time domain consecutively, the lengths of the GIs corresponding to different synchronization sequences can be the same. For example, in the scenario shown in FIG. 11, L1≠L2≠L3, but L1=L6, L2=L5, and L3=L4.

[0193] Optionally, the synchronization information can further include a third synchronization sequence, and the third synchronization sequence corresponds to a third CP and a third GI. In this embodiment, the synchronization information includes the synchronization sequences repeated in time domain consecutively, and in the case where the synchronization information includes multiple different synchronization sequences, there can be synchronization sequences not repeated. For example, the synchronization sequence 1 is repeated N1≥2 times, and the synchronization sequence 2 is repeated N2=1 time. That is, the synchronization sequence 2 is not repeated, and only the synchronization sequence 1 is repeated; or the synchronization sequence 1 is repeated N1=1 time, and the synchronization sequence 2 is repeated N2≥2 times, that is, the synchronization sequence 1 is not repeated, and only the synchronization sequence 2 is repeated.

[0194] Exemplarily, when the multiple synchronization sequences are repeated in time domain consecutively, the different synchronization sequences can be arranged in time domain in a cross manner. For example, the pth first synchronization sequence and the (p+1)th first synchronization sequence are separated by X second synchronization sequences, where p and X are positive integers, p+1 is less than or equal to N, and X is less than or equal to M. It can be understood that one or more second synchronization sequences are arranged between two first synchronization sequences consecutively in time domain.

[0195] Optionally, if the different synchronization sequences are arranged in time domain in a cross manner, the pattern of the different synchronization sequences can be indicated by protocol predefinition or by indication information. For example, the time domain starting position of the synchronization sequence 1 and / or the interval between two synchronization sequences 1 consecutively is indicated (or predefined); for another example, the time domain starting position of the synchronization sequence 2 and / or the interval between two synchronization sequences 2 consecutively is indicated (or predefined).

[0196] As shown in (a) of FIG. 14, the synchronization sequences can be arranged in a cross manner as synchronization sequence 1, synchronization sequence 2, synchronization sequence 1, synchronization sequence 2, synchronization sequence 1, and synchronization sequence 2.

[0197] As shown in (b) of FIG. 14, the synchronization sequences can be arranged in a cross manner as synchronization sequence 1, synchronization sequence 1, synchronization sequence 2, synchronization sequence 2, synchronization sequence 1, and synchronization sequence 2.

[0198] It should be understood that (a) and (b) in FIG. 14 are only examples and do not constitute any limitation on the scope of protection of the present application. The time-domain cross arrangement between different synchronization sequences can be various, which will not be described here.

[0199] By way of example but not limitation, the synchronization information further includes one secondary synchronization signal (SSS) and one physical broadcast channel (PBCH), wherein the synchronization information occupies 14 OFDM symbols, and the first to eleventh OFDM symbols carry 11 first synchronization sequences.

[0200] As shown in FIG. 15, the above-mentioned synchronization information is an enhanced design for SSB, especially for PSS in SSB. Each PSS occupies one symbol and is repeated 11 times, and the 11 PSS sequences correspond to 11 different CP and / or GI lengths. (For example, the 11 CPs can use the 11 lengths corresponding to N=11 in Table 1a; for another example, the 11 GIs can use the 11 lengths corresponding to N=11 in Table 1a; for another example, the 11 CPs and GIs can use the 11 lengths corresponding to N=11 in Table 1a), and the SSS and PBCH jointly occupy 3 symbols, i.e., the PSS, SSS, and PBCH jointly occupy 14 symbols.

[0201] For example, the PSS, SSS, and PBCH occupy 20 resource blocks (RBs) in the frequency domain, and the subcarriers (SCs) in the RBs are numbered from 0 to 239. The PSS is located on the middle 127 SCs of each symbol 0-10, and the SSS is located on the middle 127 SCs of symbol 12. The PBCH occupies all SCs of symbols 11 and 13, and the SCs of symbol 12 except for the SSS and the guard bands (8 and 9 SC guard bands are left on both sides of the SSS). Periodic repetition is performed in the manner of FIG. 15, and the receiving end can jointly detect and decode the multiple periodic repetitions of the SSS and PBCH.

[0202] In addition, if the synchronization information is an enhanced design for SSB, the pattern of the enhanced SSB can be different from the existing SSB pattern, for example, the enhanced SSB cannot be transmitted within the first 5 ms of each transmission period; for another example, the transmission period of the enhanced SSB can be greater than 20 ms, etc. It should be understood that in this embodiment, the transmission period of the synchronization information and the transmission time in each period are not limited, and the synchronization information includes multiple synchronization sequences transmitted in time domain repetition.

[0203] Further, after the first device generates the synchronization information, the first device can transmit the synchronization information to the second device, and the method flow shown in FIG. 9 further includes:

[0204] S920, the first device sends the synchronization information to the second device, and correspondingly, the second device receives the synchronization information from the first device.

[0205] By way of example and not limitation, the first device sends the number of repeated synchronization sequences and the corresponding CP / GI length to the second device, which can be at least one of broadcast information including system information block (SIB) 1, SIB 19, other system information (OSI), master information block (MIB), physical broadcast channel (PBCH) message, etc., broadcast or multicast by the first device to the second device.

[0206] The first device broadcasts or multicasts the above signaling to the second device can avoid scheduling different resources for different UEs to send the above signaling, saving signaling overhead of scheduling resources and reducing system scheduling complexity.

[0207] In addition, if it is sent in the radio resource control (RRC) connection establishment stage and subsequent communication process, the network device can carry the above signaling or indicate the above signaling / parameter value to the UE in the form of a table through at least one of RRC signaling (such as RRC setup message, RRC reconfiguration signaling (RRCReconfiguration), RRC resume signaling (RRCResume), etc.), downlink control information (DCI), group DCI, media access control (MAC) control element (CE), timing advance command (TAC), or unicast or multicast to the UE with data transmission or in a separately allocated physical downlink shared channel (PDSCH) bearer. The advantage of sending the above signaling to the UE individually or in groups is that the parameter value of each / each group of UEs can be flexibly controlled, and different parameter values can be configured to the UE according to the different positions or different areas where the UE is located to optimize system parameters and optimize UE communication performance / system communication performance. For example, different synchronization sequence repetition times and different CP / GI lengths can be configured to the UE according to different positions where the UE is located, and the configuration parameters of the synchronization sequence can be optimized for UEs in different positions to improve the resource utilization of system transmission.

[0208] As a possible implementation, the first communication device can send the first indication information to the second communication device to indicate, by the first indication information, that the synchronization sequences included in the synchronization information correspond to the CP and / or the GI. For example, the first indication information is used to indicate that each of the N first synchronization sequences corresponds to the first CP and / or the first GI.

[0209] As another possible implementation, the synchronization sequences included in the synchronization information can be predefined by a protocol or a technical standard or a technical specification, without the need for indication by the first indication information described above, thereby reducing signaling overhead.

[0210] Further, after the second communication device receives the synchronization information described above, the second communication device can perform downlink synchronization based on the synchronization information. Therefore, the method flow shown in FIG. 9 further includes:

[0211] S930, the second communication device performs downlink synchronization based on the synchronization information.

[0212] Specifically, in this embodiment, the synchronization information includes multiple synchronization sequences repeatedly transmitted in the time domain, and the second communication device can receive the multiple synchronization sequences for downlink synchronization at a time and perform downlink synchronization based on the multiple synchronization sequences.

[0213] As an example but not limitation, in the process of actually detecting the synchronization sequences by the second communication device in this embodiment, the second communication device can receive the synchronization information as a whole, for example, after the first communication device and the second communication device agree on the number of times of sending the synchronization sequences, the second communication device receives all the synchronization sequences and then performs detection; or,

[0214] In the process of actually detecting the synchronization sequences by the second communication device in this embodiment, the second communication device can stop detection after successfully detecting one or several synchronization sequences.

[0215] In the communication method shown in FIG. 9, the synchronization information sent by the first communication device includes synchronization sequences repeatedly transmitted in time domain units (such as time slots, frames, or subframes, etc.) in succession, and the lengths of the CP and / or the GI corresponding to each sequence are different. Therefore, when the second communication device performs downlink synchronization based on the synchronization information, the influence of timing drift can be avoided, and the downlink synchronization detection performance can be improved. In addition, since the lengths of the CP and / or the GI corresponding to each sequence are different, the influence of detection sub-peak can be reduced, and the downlink synchronization detection performance can be improved.

[0216] For example, due to the time-domain continuous repetition of the synchronization sequence for N times, the second communication device can receive N synchronization sequences for downlink synchronization in a single time. Thus, it can be avoided that the joint detection of the multiple times of repeated SSB (e.g., the joint detection of the multiple times of repeated PSS) cannot be performed due to large timing drift, resulting in downlink synchronization failure.

[0217] For example, due to the different CP and / or GI lengths corresponding to each sequence, the detection of the secondary peak can be reduced to improve the downlink synchronization detection performance.

[0218] For example, the length of the CP and / or GI in the time unit in which the synchronization sequence is transmitted is different from the length of the CP and / or GI in the time unit or frequency domain unit in which the data and / or control information is transmitted. For the convenience of description, the CP is taken as an example for description. The case of GI or CP and GI is similar to the CP, and is not described repeatedly.

[0219] For example, the control information carried in the time unit or frequency domain unit is taken as an example for description. The control information (or data and control information) carried in the time unit or frequency domain unit is similar to the data carried in the time unit or frequency domain unit, and is not described repeatedly. N data and N CP and / or N GI are carried in the time unit or frequency domain unit. The N data and the N CP correspond to each other one by one, and the CP corresponding to each data is located before the data in the time domain. The N data and the N GI correspond to each other one by one, and the GI corresponding to each data is located before the data in the time domain.

[0220] Possibility one:

[0221] The synchronization information is carried in a first time unit, and the data and / or control information is carried in a second time unit. The length of the ith CP in the second time unit is the same as the length of the ith CP in the first time unit, where i takes a value from 1 to N, and the second time unit is used to carry the data and / or control information. The time unit can be a slot, a subframe, or a frame. For example, the first time unit is slot #1, and the second time unit is slot #2. The slot #1 and the slot #2 can be two adjacent slots or non-adjacent slots in the time domain.

[0222] In the case shown in possibility one, the length of the CP in the time unit in which the repeated synchronization sequence is transmitted can be the same as the length of the CP in the time unit in which the data is transmitted (or the length of the CP of the symbol in which the repeated synchronization sequence is transmitted can be the same as the length of the CP of the symbol in which the data is transmitted), that is, the lengths of the CPs and GIs between the symbols in the slot in which the synchronization sequence is transmitted and the slot in which the data is transmitted are the same (for example, the position of the synchronization sequence in FIG. 10 is replaced by the position of the data). The CPs of the slots have the same length, and the processing complexity of the receiver is low.

[0223] As shown in FIG. 16, the first time unit is a time unit for transmitting a repeated synchronization sequence, and the second time unit is a time unit for transmitting data. The CP length in the first time unit is the same as the CP length in the second time unit. As shown in FIG. 16, L1 in the first time unit=L1 in the second time unit, L2 in the first time unit=L2 in the second time unit, L3 in the first time unit=L3 in the second time unit, and LN in the first time unit=LN in the second time unit.

[0224] Possibility II:

[0225] The synchronization information is carried in the first time unit, and the data and / or control information is carried in the second time unit. The length of the jth CP in the second time unit is different from the length of the jth CP in the first time unit, where j is at least one of 1 to N, and the second time unit is used to carry the data and / or control information.

[0226] In the case shown in Possibility II, the CP length in the time unit for transmitting a repeated synchronization sequence can be different from the CP length in the time unit for transmitting data (or the CP of a symbol for transmitting a repeated synchronization sequence can be different from the CP of a symbol for transmitting data), that is, the CP length of each symbol in the time unit for transmitting a synchronization sequence and the time unit for transmitting data can be different (it can also be understood that the CP in the time unit for transmitting data is completely different from or not completely the same as the CP length for transmitting a synchronization sequence in FIG. 10).

[0227] For example, the CP lengths in the time unit for transmitting data can be the same. For another example, the CP length in the time unit for transmitting data can be designed with reference to the design of the CP length in the prior art, and the CP in the time unit for transmitting data can be designed with reference to the prior art, which can better compatible with existing terminals.

[0228] As shown in FIG. 16, the first time unit is a time unit for transmitting a repeated synchronization sequence, and the second time unit is a time unit for transmitting data. At least one of the CP lengths L1, L2, …, LN in the first time unit is different from at least one of the CP lengths L1, L2, …, LN in the first time unit. For example, L1 in the first time unit≠L1 in the second time unit.

[0229] Possibility III:

[0230] The synchronization information is carried in the first time unit and the first frequency domain unit, and the data and / or control information is carried in the first time unit and the second frequency domain unit. The length of the kth CP in the second frequency domain unit is the same as the length of the kth CP in the first frequency domain unit, where k is 1 to N, and the second frequency domain unit is used to carry the data and / or control information.

[0231] In the case shown in possible three, for the time unit in which the synchronization sequence is transmitted, the CP length of the same frequency domain resource and different frequency domain resources transmitting data is the same, and non-orthogonal interference can be avoided. In addition, a frequency domain guard interval between the synchronization sequence and the data can be set between different frequency domain resources.

[0232] As shown in FIG. 17, the first frequency domain unit is a frequency domain unit in which the repeated synchronization sequence is transmitted, and the second frequency domain unit is a frequency domain unit in which the data is transmitted. The CP length in the first frequency domain unit and the CP length in the second frequency domain unit are the same, as shown in FIG. 17, L1 in the first frequency domain unit = L1 in the second frequency domain unit, L2 in the first frequency domain unit = L2 in the second frequency domain unit, L3 in the first frequency domain unit = L3 in the second frequency domain unit, and LN in the first frequency domain unit = LN in the second frequency domain unit.

[0233] Possible four:

[0234] The synchronization information is carried in the first time unit and the first frequency domain unit, and the data and / or control information is carried in the first time unit and the second frequency domain unit. The length of the k1th CP in the second frequency domain unit is different from the length of the k1th CP in the first frequency domain unit, where k1 takes at least one value from 1 to N, and the second frequency domain unit is used to carry the data and / or control information.

[0235] In the case shown in possible four, for the time unit in which the synchronization sequence is transmitted, the CP length of the same frequency domain resource and different frequency domain resources transmitting data is completely different or not completely the same. As shown in FIG. 17, the first frequency domain unit is a frequency domain unit in which the repeated synchronization sequence is transmitted, and the second frequency domain unit is a frequency domain unit in which the data is transmitted. The CP length in the first frequency domain unit and the CP length in the second frequency domain unit are different, as shown in FIG. 17, L1 in the first frequency domain unit ≠ L1 in the second frequency domain unit. In addition, a frequency domain guard interval between the synchronization sequence and the data can be set between different frequency domain resources.

[0236] For example, the CP length for transmitting the data can be designed with reference to the design of the CP length in the prior art, and the CP for transmitting the data can be designed with reference to the prior art, which can better compatible with the existing terminal.

[0237] It should be understood that the total length of the CP in the time unit in which the synchronization sequence is located is consistent with the total length of the CP in the time unit in which other data is located. Alternatively, the total length of the CP used by the symbol in which the repeated synchronization sequence is located is consistent with the total length of the CP used by the symbol in which the repeated synchronization sequence is not transmitted. For example, the synchronization information is carried in the first time unit, and the total CP length in the first time unit is the same as the total CP length in the second time unit, where the second time unit is used to carry the data.

[0238] It should be understood that the size of the sequence number of the above processes does not mean the order of execution, and the execution order of the processes should be determined according to their functions and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0239] It should also be understood that 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.

[0240] It should also be understood that in some of the above embodiments, the existing network architecture is mainly exemplified by devices, and it should be understood that the specific form of the device is not limited by the embodiments of the present application. For example, devices that can achieve the same function in the future are also applicable to the embodiments of the present application.

[0241] It can be understood that the methods and operations implemented by the devices (such as the first communication device and the second communication device) in the above various method embodiments can also be implemented by components (such as chips or circuits) that can be used for the devices.

[0242] It can also be understood that some optional features in various embodiments of the present application can not depend on other features in some scenarios, or can be combined with other features in some scenarios, and are not limited. In addition, simple modifications of the embodiments of the present application are also within the protection scope of the present application. For example, in the communication method shown in Figure 9, the first communication device is taken as an access network device, and the second communication device is taken as a terminal device, and the synchronization information is used for downlink synchronization. If the first communication device is a terminal device and the second communication device is an access network device, the above scheme can be extended to an uplink synchronization scenario, that is, the terminal device can send the above synchronization information (such as multiple repeated synchronization sequences) to the access network device, and the access network device detects the synchronization information to perform uplink synchronization. The description of the synchronization information can refer to the description of the synchronization information in Figure 9 above, and will not be repeated here.

[0243] The above describes the communication method provided by the embodiments of the present application in detail in combination with Figure 9. The above communication method is mainly introduced from the perspective of the first communication device and the second communication device. It can be understood that the first communication device and the second communication device contain corresponding hardware structures and / or software modules for executing various functions in order to achieve the above functions.

[0244] Those skilled in the art should clearly understand that units and algorithm steps of each example described in combination with the embodiments disclosed herein can be realized in the form of hardware or a combination of hardware and computer software. Whether a certain function is realized in the form of hardware or computer software driving hardware depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to realize the described functions for each specific application, but such implementation should not be considered beyond the scope of the present application.

[0245] The following describes the communication apparatus provided by the embodiments of the present application in combination with FIG. 18 and FIG. 19. It should be understood that the description of the apparatus embodiments corresponds to the description of the method embodiments, and therefore, the content not described in detail can be referred to the method embodiments described above, and some content will not be described again for the sake of brevity.

[0246] The embodiments of the present application can divide the functional modules of the sending end device or the receiving end device according to the method examples described above, for example, each functional module can be divided according to each function, or two or more functions can be integrated in one processing module. The integrated module can be realized in the form of hardware or software functional module. It should be noted that the division of the modules in the embodiments of the present application is illustrative, and is only a logical function division, and another division method can be used in actual implementation. The following will be described taking the example of dividing each functional module according to each function.

[0247] FIG. 18 is a schematic block diagram of the communication apparatus 10 provided by the embodiments of the present application. The communication apparatus 10 includes a transceiver module 11 and a processing module 12. The transceiver module 11 can realize corresponding communication functions, and the processing module 12 is used for data processing, or in other words, the transceiver module 11 is used for executing the operations related to receiving and sending, and the processing module 12 is used for executing the operations other than receiving and sending. The transceiver module 11 can also be referred to as a communication interface or a communication unit. The transceiver module 11 can include a receiving module and / or a sending module, the receiving module is used for executing the operations related to receiving, and the sending module is used for executing the operations related to sending.

[0248] Optionally, the communication apparatus 10 can also include a storage module 13, which can be used for storing computer programs or instructions and / or data, and the processing module 12 can read the computer programs or instructions and / or data in the storage module, so that the apparatus realizes the actions of the device in each of the foregoing method embodiments; the above modules can also be referred to as units, such as a transceiver unit, a processing unit, a storage unit, etc.

[0249] In one design, the communication apparatus 10 can correspond to the first communication apparatus in the method embodiments described above, or be a component (such as a chip) of the first communication apparatus.

[0250] The communication apparatus 10 can implement the steps or procedures corresponding to those performed by the first communication apparatus in the above method embodiments, wherein the transceiver module 11 can be configured to perform the transceiver-related operations of the first communication apparatus in the above method embodiments, and the processing module 12 can be configured to perform the processing-related operations of the first communication apparatus in the above method embodiments.

[0251] In a possible implementation, the processing module 12 is configured to generate synchronization information for downlink synchronization. The transceiver module 11 is configured to transmit the synchronization information, wherein the synchronization information comprises N first synchronization sequences, the N first synchronization sequences correspond to N first CPs respectively, and / or the N first synchronization sequences correspond to N first GIs respectively, any two of the N first CPs have different lengths, any two of the N first GIs have different lengths, and N is an integer greater than 1.

[0252] When the communication apparatus 10 is configured to perform the method in FIG. 9, the transceiver module 11 can be configured to perform the steps of transmitting information in the method, such as step S920, and the processing module 12 can be configured to perform the processing steps in the method, such as step S910.

[0253] It should be understood that the specific process of each unit performing the corresponding steps has been described in detail in the above method embodiments, and thus will not be described here for brevity.

[0254] In another design, the communication apparatus 10 can correspond to the second communication apparatus in the above method embodiments, or be a component (e.g., a chip) of the second communication apparatus.

[0255] The communication apparatus 10 can implement the steps or procedures corresponding to those performed by the second communication apparatus in the above method embodiments, wherein the transceiver module 11 can be configured to perform the transceiver-related operations of the second communication apparatus in the above method embodiments, and the processing module 12 can be configured to perform the processing-related operations of the second communication apparatus in the above method embodiments.

[0256] In a possible implementation, the transceiver module 11 is configured to receive synchronization information for downlink synchronization. The processing module 12 is configured to perform downlink synchronization based on the synchronization information, wherein the synchronization information comprises N first synchronization sequences, the N first synchronization sequences correspond to N first CPs respectively, and / or the N first synchronization sequences correspond to N first GIs respectively, any two of the N first CPs have different lengths, any two of the N first GIs have different lengths, and N is an integer greater than 1.

[0257] When the communication apparatus 10 is configured to perform the method in FIG. 9, the transceiver module 11 can be configured to perform the step of transceiving information in the method, such as step S920; and the processing module 12 can be configured to perform the processing step in the method, such as step S930.

[0258] It should be understood that the specific process of each module or unit performing the corresponding steps described above has been described in detail in the method embodiments described above, and for the sake of brevity, will not be repeated here.

[0259] It should also be understood that the communication apparatus 10 herein is embodied in the form of functional modules. The term "module" herein can refer to an application specific integrated circuit (ASIC), an electronic circuit, a processor (for example, a shared processor, a dedicated processor, or a group processor, etc.) and a memory for executing one or more software or firmware programs, a combination of logic circuitry and / or other suitable components that support the described functions. In an optional example, those skilled in the art can understand that the apparatus 10 can be embodied as the mobility management network element in the above embodiments, and can be configured to perform the processes and / or steps corresponding to the mobility management network element in the above method embodiments; or the apparatus 10 can be embodied as the terminal device in the above embodiments, and can be configured to perform the processes and / or steps corresponding to the terminal device in the above method embodiments, and for the sake of brevity, will not be repeated here.

[0260] The communication apparatus 10 of each of the above schemes has the function of performing the corresponding steps performed by the device (such as the first communication apparatus) in the above method. The function can be realized by hardware, or realized by hardware executing corresponding software. The hardware or software includes one or more modules corresponding to the above functions; for example, the transceiver module can be replaced by a transceiver (for example, the sending module in the transceiver module can be replaced by a transmitter, and the receiving module in the transceiver module can be replaced by a receiver), and other units, such as the processing module, can be replaced by a processor, which respectively performs the transceiving operations and related processing operations in each method embodiment.

[0261] In addition, the transceiver module 11 described above can also be a transceiver circuit (for example, which can include a receiving circuit and a sending circuit), and the processing module can be a processing circuit.

[0262] FIG. 19 is a schematic diagram of another communication apparatus 20 provided by the embodiments of the present application. The communication apparatus 20 includes a processor 21, which is configured to execute computer programs or instructions stored in a memory 22, or read data / signaling stored in the memory 22, to perform the methods in the above method embodiments. Optionally, the processor 21 is one or more.

[0263] Optionally, as shown in FIG. 19, the communication apparatus 20 further includes a transceiver 23 configured to receive and / or send signals. For example, the processor 21 is configured to control the transceiver 23 to receive and / or send signals. The transceiver 23 can include a receiver configured to receive signals and / or a transmitter configured to send signals. If the communication apparatus 20 is a chip, the transceiver 23 is an input / output interface of the chip, where the output corresponds to the sending and the input corresponds to the receiving.

[0264] Optionally, as shown in FIG. 19, the communication apparatus 20 further includes a memory 22 configured to store computer programs or instructions and / or data. The memory 22 can be integrated with the processor 21 or can be separately arranged. Optionally, the memory 22 is one or more.

[0265] As an option, the communication apparatus 20 is configured to implement operations performed by the first communication apparatus or the second communication apparatus in the above various method embodiments.

[0266] It should be understood that the processor mentioned in the embodiments of the present application can be a central processing unit (CPU), and can also be other general-purpose processors, digital signal processors (DSP), application specific integrated circuits (ASIC), field programmable gate arrays (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor.

[0267] It should also be understood that the memory referred to in the embodiments of the application can be a volatile memory and / or a non-volatile memory. Among them, the non-volatile memory can be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically EPROM (EEPROM) or a flash memory. The volatile memory can be a random access memory (RAM). For example, the RAM can be used as an external cache. As an example but not limitation, the RAM includes the following various forms: static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchlink DRAM (SLDRAM) and direct rambus RAM (DR RAM).

[0268] It should be noted that when the processor is a general processor, DSP, ASIC, FPGA or other programmable logic device, discrete gate or transistor logic device, discrete hardware component, the memory (storage module) can be integrated in the processor.

[0269] It should also be noted that the memory described herein is intended to include, but not limited to, these and any other suitable type of memory.

[0270] The embodiments of the application provide a chip system. The chip system (or also can be called processing system) includes a logic circuit and an input / output interface.

[0271] Among them, the logic circuit can be a processing circuit in the chip system. The logic circuit can be coupled to the storage unit, call the instructions in the storage unit, so that the chip system can realize the method and function of the embodiments of the application. The input / output interface can be an input / output circuit in the chip system, output the information processed by the chip system, or input the data or signaling information to be processed into the chip system for processing.

[0272] As a solution, the chip system is configured to implement operations performed by the first communication device or the second communication device in the above method embodiments.

[0273] For example, the logic circuit is configured to implement processing-related operations performed by the first communication device or the second communication device in the above method embodiments; and the input / output interface is configured to implement sending and / or receiving-related operations performed by the terminal device in the above method embodiments.

[0274] The embodiments of the present application further provide a computer readable storage medium, which stores computer instructions for implementing the method performed by the device in the above method embodiments.

[0275] For example, the computer program, when executed by a computer, enables the computer to implement the method performed by the first communication device or the second communication device in the above method embodiments.

[0276] The embodiments of the present application further provide a computer program product, which contains the computer program or instructions, and the computer program or instructions, when executed by a computer, implement the method performed by the first communication device or the second communication device in the above method embodiments.

[0277] The embodiments of the present application further provide a communication system, which includes the first communication device and the second communication device as described above.

[0278] The above description of the related content of any of the devices provided above and the beneficial effects can refer to the corresponding method embodiments provided above, and will not be described here again.

[0279] Those skilled in the art can understand that the units and algorithm steps of the examples described in combination with the embodiments disclosed herein can be realized by electronic hardware or a combination of computer software and electronic hardware. Whether the functions are realized in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the present application.

[0280] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the above-described system, device and unit can refer to the corresponding processes in the above method embodiments, which will not be described here again.

[0281] In several embodiments provided in the present application, it should be understood that the disclosed system, device and method can be implemented in other manners. For example, the described device embodiments are merely schematic. The division of the units is merely logical function division. There can be other division manners in actual implementation. For example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the displayed or discussed mutual couplings or direct couplings or communication connections can be indirect couplings or communication connections through some interfaces, devices or units, and can be in electrical, mechanical or other forms.

[0282] The units described as separate components can or can not be physically separate, and the components shown as units can or can not be physical units, i.e., can be located in one place, or can be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the embodiment.

[0283] In addition, each functional unit in the various embodiments of the present application can be integrated into a processing unit, or each unit can be a physically separate unit, or two or more units can be integrated into one unit.

[0284] If the functions are realized in the form of software function units and sold or used as independent products, they can be stored in a computer readable storage medium. Based on this understanding, the technical solutions of the present application can be embodied in the form of a software product, and the computer software product is stored in a storage medium, and includes a number of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present application. The aforementioned storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and various media that can store program codes.

[0285] The above is merely specific embodiments of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art can easily think of changes or replacements within the technical scope disclosed in the present application, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A communication method characterized by comprising: The method comprises: generating synchronization information, the synchronization information being used for downlink synchronization, the synchronization information comprising N first synchronization sequences; transmitting the synchronization information, wherein the synchronization information further comprises N first cyclic prefix (CP) and / or N first guard interval (GI), the N first synchronization sequences correspond to the N first CP one by one, and the N first synchronization sequences correspond to the N first GI one by one, any two of the N first CPs have different lengths, any two of the N first GIs have different lengths, and the N is an integer greater than 1.

2. The method of claim 1, wherein, The method further comprises: transmitting first indication information, the first indication information being used for indicating that each of the N first synchronization sequences corresponds to a first CP and / or a first GI.

3. The method according to claim 1 or 2, characterized in that, The method further comprises: transmitting data and / or control information, wherein the synchronization information is carried in a first time unit, the data and / or control information is carried in a second time unit, a length of an i-th CP in the second time unit is the same as a length of the i-th CP in the first time unit, and / or a length of an i-th GI in the second time unit is the same as a length of the i-th GI in the first time unit, i being an integer from 1 to N.

4. The method according to claim 1 or 2, characterized in that, The method further comprises: transmitting data and / or control information, wherein the synchronization information is carried in a first time unit, the data and / or control information is carried in a second time unit, a length of a j-th CP in the second time unit is different from a length of the j-th CP in the first time unit, and / or a length of a j-th GI in the second time unit is different from a length of the j-th GI in the first time unit, j being at least one of integers from 1 to N.

5. The method according to claim 1 or 2, characterized in that, The method further comprises: transmitting data and / or control information, wherein the synchronization information is carried in a first time unit and a first frequency domain unit, the data and / or control information is carried in a first time unit and a second frequency domain unit, a length of a k-th CP in the second frequency domain unit is the same as a length of the k-th CP in the first frequency domain unit, and / or a length of a k-th GI in the second frequency domain unit is the same as a length of the k-th GI in the first frequency domain unit, k being an integer from 1 to N.

6. A communication method characterized by comprising: The method comprises: receiving synchronization information, the synchronization information being used for downlink synchronization, the synchronization information comprising N first synchronization sequences; performing downlink synchronization based on the synchronization information, wherein the synchronization information further comprises N first cyclic prefix (CP) and / or N first guard interval (GI), the N first synchronization sequences correspond to the N first CP one by one, and the N first synchronization sequences correspond to the N first GI one by one, any two of the N first CPs have different lengths, any two of the N first GIs have different lengths, and the N is an integer greater than 1.

7. The method of claim 6, wherein, The method further comprises: receiving first indication information, the first indication information being used for indicating that each of the N first synchronization sequences corresponds to a first CP and / or a first GI.

8. The method according to claim 6 or 7, characterized in that, The method further comprises: receiving data and / or control information, wherein the synchronization information is carried in a first time unit, the data and / or control information is carried in a second time unit, a length of an i-th CP in the second time unit is the same as a length of the i-th CP in the first time unit, and / or a length of an i-th GI in the second time unit is the same as a length of the i-th GI in the first time unit, i being an integer from 1 to N.

9. The method according to claim 6 or 7, characterized in that, The method further comprises: receiving data and / or control information, wherein the synchronization information is carried in a first time unit, the data and / or control information is carried in a second time unit, a length of a j-th CP in the second time unit is different from a length of the j-th CP in the first time unit, and / or a length of a j-th GI in the second time unit is different from a length of the j-th GI in the first time unit, j being at least one of an integer from 1 to N.

10. The method of claim 6 or 7, wherein, The method further comprises: receiving data and / or control information, wherein the synchronization information is carried in a first time unit and a first frequency domain unit, the data and / or control information is carried in the first time unit and a second frequency domain unit, a length of a k-th CP in the second frequency domain unit is the same as a length of the k-th CP in the first frequency domain unit, and / or a length of a k-th GI in the second frequency domain unit is the same as a length of the k-th GI in the first frequency domain unit, k being an integer from 1 to N.

11. The method according to any one of claims 1 to 10, characterized in that, The synchronization information further comprises M second synchronization sequences, the M second synchronization sequences respectively correspond to M second CPs, and / or the M second synchronization sequences respectively correspond to M second GI lengths, wherein lengths of any two of the M second CPs are different, lengths of any two of the M second GIs are different, and the M is an integer greater than 1.

12. The method of claim 11, wherein, One or more of the second synchronization sequences are arranged between two of the first synchronization sequences in the time domain.

13. The method according to any one of claims 1 to 12, characterized in that, A sum of lengths of first CPs corresponding to consecutive m2 first synchronization sequences starting from an m1-th first synchronization sequence is different from a sum of lengths of first CPs corresponding to consecutive m4 first synchronization sequences starting from an m3-th first synchronization sequence, wherein m1, m2, and m4 are positive integers, and m3 is a positive integer greater than or equal to a sum of m1 and m2.

14. The method according to any one of claims 1 to 13, characterized in that, The N first CPs satisfy any one of the following conditions: lengths of the N first CPs increase in order from small to large; or lengths of the N first CPs decrease in order from large to small; or a ratio of lengths of two adjacent first CPs in the N first CPs is a preset value; or the N and lengths of the N first CPs satisfy a first correspondence relationship.

15. The method of claim 14, wherein, The first correspondence includes: In the table, L1 and L2 in the second row represent lengths of two first CPs corresponding to two first synchronization sequences respectively when N is equal to 2; and L1, L2, and L3 in the third row represent lengths of three first CPs corresponding to three first synchronization sequences respectively when N is equal to 3.

16. The method according to any one of claims 1 to 15, characterized in that, The N first GIs satisfy any one of the following conditions: lengths of the N first GIs increase in order from small to large; or, lengths of the N first GIs decrease in order from large to small; or, a ratio of lengths of two first GIs adjacent in the N first GIs is a preset value; or, a value of the N and each GI length in the lengths of the N first GIs satisfy a second corresponding relationship.

17. The method of claim 16, wherein, The second correspondence includes: In the table, L1' and L2' in the second row represent lengths of two first GIs corresponding to two first synchronization sequences respectively in a case where N is equal to 2; L1', L2' and L3' in the third row represent lengths of three first GIs corresponding to three first synchronization sequences respectively in a case where N is equal to 3.

18. The method of any one of claims 1 to 17, wherein, The synchronization information is a synchronization broadcast block (SS / PBCH block), the SS / PBCH block includes N primary synchronization signals (PSSs), one secondary synchronization signal (SSS) and one physical broadcast channel (PBCH), and the N PSSs are the N first synchronization sequences.

19. The method of claim 18, wherein, The SS / PBCH block occupies 14 orthogonal frequency division multiplexing (OFDM) symbols in a time domain, the N PSSs occupy the first to eleventh OFDM symbols, and the PSSs include eleven first synchronization sequences.

20. A communications device, characterized by comprise: one or more functional modules for performing the method of any one of claims 1 to 5 or 11 to 19, or one or more functional modules for performing the method of any one of claims 6 to 19.

21. A communications device, characterized by comprise: a processor configured to execute a computer program stored in a memory, so that the apparatus performs the method of any one of claims 1 to 5 or 11 to 19, or so that the apparatus performs the method of any one of claims 6 to 19.

22. A computer program product, characterised in that, The computer program product comprises instructions for performing the method of any one of claims 1 to 19.

23. A computer-readable storage medium, comprising: comprise: The computer readable storage medium stores a computer program or instructions; the computer program or instructions, when running on a computer, cause the computer to perform the method of any one of claims 1 to 19.

24. A chip, characterized by The chip is installed in a communication device, the chip comprises a processor and a communication interface, the processor reads a computer program or instructions through the communication interface and runs, so that the communication device performs the method of any one of claims 1 to 19. The chip is installed in a communication device, the chip comprises a processor and a communication interface, the processor reads a computer program or instructions through the communication interface and runs, so that the communication device performs the method of any one of claims 1 to 19.

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