Synchronization signal transmission method, apparatus and system

Abstract

Embodiments of the present application provide a synchronization signal transmission method, an apparatus and a system, used for improving the synchronization signal transmission quality. The method comprises: on the basis of the correspondence between precoders and subsequence groups, precoding a plurality of subsequences comprised in a synchronization sequence, wherein a first subsequence among the plurality of subsequences is precoded by using a precoder corresponding to a subsequence group where the first subsequence is located; and sending a synchronization signal, wherein the synchronization signal comprises the plurality of precoded subsequences.

Description

Synchronization signal transmission method, device and system

[0001] This application claims priority to the Chinese patent application filed with the State Intellectual Property Office on November 14, 2023, with application number 202311524555.1 and application name “Method, device and system for transmitting synchronization signals”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of communication technology, and in particular to a method, device, and system for transmitting a synchronization signal. Background Art

[0003] Precoding technology is commonly used in multiple-input, multiple-output (MIMO) systems. At the transmitter, a precoder can be used to optimize the spatial characteristics of the transmitted signal, thereby eliminating interference between users.

[0004] In existing transmission solutions, a base station uses a precoder to send a signal only after sending a synchronization signal to a user equipment (UE), which results in the transmission quality of the synchronization signal being unable to be guaranteed.

[0005] Summary of the Invention

[0006] The embodiments of the present application provide a method, device, and system for transmitting a synchronization signal, which are used to improve the transmission quality of the synchronization signal.

[0007] To achieve the above objectives, the embodiments of the present application adopt the following technical solutions:

[0008] In a first aspect, a method for transmitting a synchronization signal is provided. The apparatus performing the method may be a network device, or a module employed in the network device, such as a chip or chip system. The method comprises: precoding multiple subsequences included in a synchronization sequence based on a correspondence between precoders and subsequence groups; wherein a first subsequence among the multiple subsequences is precoded using a precoder corresponding to the subsequence group to which the first subsequence belongs; and transmitting a synchronization signal including the precoded multiple subsequences.

[0009] In the synchronization signal transmission method provided in the embodiment of the present application, the network device can precode the subsequences according to the subsequence grouping, thereby introducing a precoder to improve the transmission quality of the synchronization signal, thereby enabling the terminal device to achieve downlink synchronization faster and more accurately. In addition, the broadband terminal device can receive a complete synchronization signal including multiple precoded subsequences, and the narrowband terminal device can receive a partial synchronization signal including one or more precoded subsequences. For broadband terminal devices and narrowband terminal devices, the embodiment of the present application can adopt the same synchronization signal transmission structure, thereby reducing the complexity of the cellular network system design and achieving the technical effect of saving time and frequency resources.

[0010] In conjunction with the first aspect above, in one possible implementation, the total length of the subsequences included in the subsequence group is an integer multiple of a first preset value. The first preset value in this solution may be the number of subcarriers included in the minimum PRG, so that this solution is compatible with parameter settings in existing precoding technologies.

[0011] In conjunction with the first aspect above, in one possible implementation, the total length of the subsequences included in the subsequence group is an integer multiple of a second preset value, where the total length of the subsequences included in the subsequence group is obtained by padding. The second preset value in this solution can be less than or equal to the first preset value. In other words, this solution can overcome the minimum PRG limitation in existing precoding technologies.

[0012] In combination with the first aspect above, in a possible implementation, the correspondence between the precoder and the subsequence grouping includes: the precoders corresponding to each M subsequence groupings constitute the same precoder set, and the precoder set includes M different precoders, M is a positive integer, 1<M<K, K represents the number of subsequence groups, and K is a positive integer. In this solution, the network device uses multiple precoders, and can select a precoder with better reception performance for subsequent network devices to transmit signals to terminal devices. The embodiment of the present application does not impose any restrictions on the order of the precoders corresponding to each M subsequence groupings. The order of the precoders corresponding to each M subsequence groupings can be the same or different.

[0013] In conjunction with the first aspect above, in one possible implementation, the precoders corresponding to each of the M subsequence groups constitute the same precoder set, including: the precoders corresponding to each of the M subsequence groups are the same. In this solution, the order of the precoders corresponding to each of the M subsequence groups can be the same.

[0014] In combination with the first aspect above, in a possible implementation, the precoders corresponding to every M subsequence groups constitute the same precoder set, including: the index value of the precoder is the remainder obtained by dividing the index value of the subsequence group by M.

[0015] With reference to the first aspect above, in a possible implementation, the correspondence between the precoder and the subsequence grouping includes: the precoders corresponding to each subsequence grouping are different from each other.

[0016] In combination with the first aspect above, in a possible implementation, the precoder corresponding to any subsequence group corresponds to one codeword from K codewords selected from the precoding matrix, where K represents the number of subsequence groups and is a positive integer.

[0017] In conjunction with the first aspect above, in one possible implementation, K is less than or equal to N, where N represents the number of antennas and is a positive integer, and the K codewords are mutually orthogonal. This solution can achieve diversity gain through multi-antenna design.

[0018] In combination with the above first aspect, in a possible implementation, K is greater than N, N represents the number of antennas, and N is a positive integer. The K codewords include N mutually orthogonal codewords, and the mutual correlation between the K codewords is minimized.

[0019] In conjunction with the first aspect above, in one possible implementation, the method further includes: receiving first information, the first information carrying an index of a first precoder and / or an index of a first subsequence group; the first subsequence group corresponds to the first precoder, and the first precoder is used for signal precoding. In this solution, the terminal device can select a first precoder with better reception performance and feed it back to the network device, so that the network device can subsequently use the first precoder when transmitting signals to the terminal device to improve transmission quality.

[0020] In conjunction with the first aspect, in one possible implementation, the number of subsequences included in the synchronization sequence is equal to the length of each subsequence included in the synchronization sequence. In this solution, the subsequences have good ambiguity function performance. Specifically, the correlation value of the sequence has low sidelobes at locations corresponding to erroneous delays and / or Doppler frequency offsets.

[0021] With reference to the first aspect above, in a possible implementation, the subsequence included in the synchronization sequence is a longest linear shift register sequence or a multi-phase sequence.

[0022] In conjunction with the first aspect above, in a possible implementation, the first subsequence included in the synchronization sequence is a polyphase sequence; and the general term of the first subsequence satisfies the following formula:

[0023] Wherein, a, b, c, d, p, q are constants; n=1, 2, ..., N, N represents the length of the first subsequence, and N is a positive integer; k=1, 2, ..., K, K represents the number of subsequences included in the synchronization sequence, and K is a positive integer.

[0024] In conjunction with the first aspect above, in one possible implementation, each subsequence included in the synchronization sequence occupies the same time domain resources, or each subsequence included in the synchronization sequence occupies the same frequency domain resources. When each subsequence included in the synchronization sequence occupies the same frequency domain resources, for terminal devices, especially second-type terminal devices, the synchronization sequence may not be restricted by bandwidth, so that the synchronization sequence can include more subsequences, or the synchronization sequence can carry more information.

[0025] In a second aspect, a method for transmitting a synchronization signal is provided. The apparatus for performing the method for transmitting a synchronization signal may be a terminal device, or may be a module applied to the terminal device, such as a chip or a chip system. The method for transmitting a synchronization signal includes: when the terminal device is a first type of terminal device, receiving a synchronization signal, the synchronization signal including multiple precoded subsequences; performing downlink synchronization according to the synchronization signal; or, when the terminal device is a second type of terminal device, receiving one or more precoded subsequences in the synchronization signal; performing downlink synchronization according to one or more precoded subsequences in the synchronization signal; wherein the bandwidth of the signal received by the first type of terminal device is wider than the bandwidth of the signal received by the second type of terminal device.

[0026] In combination with the above second aspect, in a possible implementation manner, the total length of the subsequences included in the subsequence group is an integer multiple of the first preset value.

[0027] In combination with the above second aspect, in a possible implementation manner, the total length of the subsequences included in the subsequence group is an integer multiple of the second preset value, wherein the total length of the subsequences included in the subsequence group is obtained by padding extension.

[0028] In combination with the above-mentioned second aspect, in one possible implementation manner, the correspondence between the precoder and the subsequence group includes: the precoders corresponding to every M subsequence groups constitute the same precoder set, and the precoder set includes M different precoders, M is a positive integer, 1<M<K, K represents the number of subsequence groups, and K is a positive integer.

[0029] In combination with the second aspect above, in a possible implementation, the precoders corresponding to each M subsequence groupings constitute the same precoder set, including: the precoders corresponding to each M subsequence groupings are the same.

[0030] In combination with the above second aspect, in a possible implementation, the precoders corresponding to every M subsequence groups constitute the same precoder set, including: the index value of the precoder is the remainder obtained by dividing the index value of the subsequence group by M.

[0031] In combination with the second aspect above, in a possible implementation manner, the correspondence between the precoder and the subsequence grouping includes: the precoders corresponding to each subsequence grouping are different from each other.

[0032] In combination with the above second aspect, in a possible implementation, the precoder corresponding to any subsequence group corresponds to one codeword from K codewords selected from the precoding matrix, where K represents the number of subsequence groups and is a positive integer.

[0033] In combination with the above second aspect, in a possible implementation, K is less than or equal to N, where N represents the number of antennas, and N is a positive integer, and the K codewords are mutually orthogonal.

[0034] In combination with the above second aspect, in a possible implementation, K is greater than N, N represents the number of antennas, and N is a positive integer. The K codewords include N mutually orthogonal codewords, and the mutual correlation between the K codewords is minimized.

[0035] In combination with the above-mentioned second aspect, in a possible implementation, the method also includes: sending first information, which carries the index of the first precoder and / or the index of the first subsequence group; the first subsequence group corresponds to the first precoder, and the first precoder is used for signal precoding.

[0036] In combination with the second aspect above, in a possible implementation manner, the number of subsequences included in the synchronization sequence is the same as the length of each subsequence included in the synchronization sequence.

[0037] In conjunction with the second aspect above, in a possible implementation, the first subsequence included in the synchronization sequence is a polyphase sequence; and the general term of the first subsequence satisfies the following formula:

[0038] Wherein, a, b, c, d, p, q are constants; n=1, 2, ..., N, N represents the length of the first subsequence, and N is a positive integer; k=1, 2, ..., K, K represents the number of subsequences included in the synchronization sequence, and K is a positive integer.

[0039] In combination with the above second aspect, in a possible implementation manner, each subsequence included in the synchronization sequence occupies the same time domain resources, or each subsequence included in the synchronization sequence occupies the same frequency domain resources.

[0040] In a third aspect, a communication device is provided for implementing the above method. The communication device includes modules, units, or means corresponding to the above method. The modules, units, or means can be implemented in hardware, software, or by hardware executing corresponding software implementations. The hardware or software includes one or more modules or units corresponding to the above functions.

[0041] In conjunction with the third aspect above, in one possible implementation, the communication device includes: a precoding module and a transceiver module. The precoding module is configured to precode multiple subsequences included in a synchronization sequence based on a correspondence between precoders and subsequence groups; wherein a first subsequence among the multiple subsequences is precoded using a precoder corresponding to the subsequence group to which the first subsequence belongs; and the transceiver module is configured to transmit a synchronization signal, wherein the synchronization signal includes the precoded multiple subsequences.

[0042] In combination with the third aspect above, in a possible implementation manner, the total length of the subsequences included in the subsequence group is an integer multiple of a first preset value.

[0043] In combination with the third aspect above, in a possible implementation, the total length of the subsequences included in the subsequence group is an integer multiple of a second preset value, wherein the total length of the subsequences included in the subsequence group is obtained by padding extension.

[0044] In combination with the above-mentioned third aspect, in one possible implementation manner, the correspondence between the precoder and the subsequence group includes: the precoders corresponding to every M subsequence groups constitute the same precoder set, and the precoder set includes M different precoders, M is a positive integer, 1<M<K, K represents the number of subsequence groups, and K is a positive integer.

[0045] In combination with the third aspect above, in a possible implementation, the precoders corresponding to each M subsequence groupings constitute the same precoder set, including: the precoders corresponding to each M subsequence groupings are the same.

[0046] In combination with the third aspect above, in a possible implementation, the precoders corresponding to every M subsequence groups constitute the same precoder set, including: the index value of the precoder is the remainder obtained by dividing the index value of the subsequence group by M.

[0047] In combination with the third aspect above, in a possible implementation manner, the correspondence between the precoder and the subsequence grouping includes: the precoders corresponding to each subsequence grouping are different.

[0048] In combination with the third aspect above, in a possible implementation, the precoder corresponding to any subsequence group corresponds to one codeword from K codewords selected from the precoding matrix, where K represents the number of subsequence groups and is a positive integer.

[0049] In combination with the third aspect above, in a possible implementation, K is less than or equal to N, where N represents the number of antennas, and N is a positive integer, and the K codewords are mutually orthogonal.

[0050] In combination with the third aspect above, in a possible implementation, K is greater than N, where N represents the number of antennas and is a positive integer. The K codewords include N mutually orthogonal codewords, and the cross-correlation between the K codewords is minimized.

[0051] In combination with the above-mentioned third aspect, in one possible implementation, the transceiver module is further used to receive first information, which carries the index of the first precoder and / or the index of the first subsequence group; the first subsequence group corresponds to the first precoder, and the first precoder is used for signal precoding.

[0052] In combination with the third aspect above, in a possible implementation manner, the number of subsequences included in the synchronization sequence is the same as the length of each subsequence included in the synchronization sequence.

[0053] In conjunction with the third aspect, in a possible implementation, the first subsequence included in the synchronization sequence is a polyphase sequence; and the general term of the first subsequence satisfies the following formula:

[0054] Wherein, a, b, c, d, p, q are constants; n=1, 2, ..., N, N represents the length of the first subsequence, and N is a positive integer; k=1, 2, ..., K, K represents the number of subsequences included in the synchronization sequence, and K is a positive integer.

[0055] In combination with the third aspect above, in a possible implementation manner, each subsequence included in the synchronization sequence occupies the same time domain resources, or each subsequence included in the synchronization sequence occupies the same frequency domain resources.

[0056] In a fourth aspect, a communication device is provided for implementing the above method. The communication device includes modules, units, or means corresponding to the above method. The modules, units, or means can be implemented in hardware, software, or by hardware executing corresponding software implementations. The hardware or software includes one or more modules or units corresponding to the above functions.

[0057] In conjunction with the fourth aspect above, in one possible implementation, the communication device includes: a transceiver module and a synchronization module. When the communication device is a first type of communication device, the transceiver module is configured to receive a synchronization signal, where the synchronization signal includes multiple precoded subsequences; and the synchronization module is configured to perform downlink synchronization based on the synchronization signal. Alternatively, when the communication device is a second type of communication device, the transceiver module is configured to receive one or more precoded subsequences in the synchronization signal; and the synchronization module is configured to perform downlink synchronization based on one or more precoded subsequences in the synchronization signal. The bandwidth of the signal received by the first type of communication device is wider than the bandwidth of the signal received by the second type of communication device.

[0058] In combination with the fourth aspect above, in a possible implementation manner, the total length of the subsequences included in the subsequence group is an integer multiple of a first preset value.

[0059] In combination with the fourth aspect above, in a possible implementation, the total length of the subsequences included in the subsequence group is an integer multiple of a second preset value, wherein the total length of the subsequences included in the subsequence group is obtained by padding extension.

[0060] In combination with the fourth aspect above, in one possible implementation, the correspondence between the precoder and the subsequence group includes: the precoders corresponding to every M subsequence groups constitute the same precoder set, and the precoder set includes M different precoders, where M is a positive integer, 1<M<K, K represents the number of subsequence groups, and K is a positive integer.

[0061] In combination with the fourth aspect above, in a possible implementation manner, the precoders corresponding to each M subsequence groupings constitute the same precoder set, including: the precoders corresponding to each M subsequence groupings are the same.

[0062] In combination with the fourth aspect above, in a possible implementation, the precoders corresponding to every M subsequence groups constitute the same precoder set, including: the index value of the precoder is the remainder obtained by dividing the index value of the subsequence group by M.

[0063] With reference to the fourth aspect above, in a possible implementation, the correspondence between the precoder and the subsequence grouping includes: the precoders corresponding to each subsequence grouping are different from each other.

[0064] In combination with the fourth aspect above, in a possible implementation, the precoder corresponding to any subsequence group corresponds to one codeword from K codewords selected from the precoding matrix, where K represents the number of subsequence groups and is a positive integer.

[0065] In combination with the fourth aspect above, in a possible implementation, K is less than or equal to N, where N represents the number of antennas, and N is a positive integer, and the K codewords are mutually orthogonal.

[0066] In combination with the fourth aspect above, in a possible implementation, K is greater than N, where N represents the number of antennas and is a positive integer. The K codewords include N mutually orthogonal codewords, and the cross-correlation between the K codewords is minimized.

[0067] In combination with the above-mentioned fourth aspect, in a possible implementation method, the transceiver module is also used to send first information, where the first information carries the index of the first precoder and / or the index of the first subsequence group; the first subsequence group corresponds to the first precoder, and the first precoder is used for signal precoding.

[0068] In combination with the fourth aspect above, in a possible implementation manner, the number of subsequences included in the synchronization sequence is the same as the length of each subsequence included in the synchronization sequence.

[0069] In conjunction with the fourth aspect, in a possible implementation, the first subsequence included in the synchronization sequence is a polyphase sequence; and the general term of the first subsequence satisfies the following formula:

[0070] Wherein, a, b, c, d, p, q are constants; n=1, 2, ..., N, N represents the length of the first subsequence, and N is a positive integer; k=1, 2, ..., K, K represents the number of subsequences included in the synchronization sequence, and K is a positive integer.

[0071] In combination with the fourth aspect above, in a possible implementation manner, each subsequence included in the synchronization sequence occupies the same time domain resources, or each subsequence included in the synchronization sequence occupies the same frequency domain resources.

[0072] In a fifth aspect, a communication device is provided, comprising: a processor; the processor is configured to be coupled to a memory, and after reading computer instructions stored in the memory, execute the method described in the first or second aspect above according to the instructions.

[0073] In combination with the fifth aspect above, in a possible implementation, the communication device further includes a memory; the memory is used to store computer instructions.

[0074] In conjunction with the fifth aspect, in one possible implementation, the communication device further includes a communication interface; the communication interface is used for the communication device to communicate with other devices. Exemplarily, the communication interface can be a transceiver, an input / output interface, an interface circuit, an output circuit, an input circuit, a pin, or related circuits.

[0075] In conjunction with the fifth aspect above, in one possible implementation, the communication device may be a chip or a chip system. When the communication device is a chip system, the communication device may be composed of a chip or may include a chip and other discrete devices.

[0076] In conjunction with the fifth aspect, in one possible implementation, when the communication device is a chip or a chip system, the communication interface may be an input / output interface, an interface circuit, an output circuit, an input circuit, a pin, or related circuits on the chip or chip system. The processor may also be embodied as a processing circuit or a logic circuit.

[0077] In a sixth aspect, a communication system is provided, comprising: a network device that executes the method described in the first aspect above, and a terminal device that executes the method described in the second aspect above.

[0078] In a seventh aspect, a computer-readable storage medium is provided, in which instructions are stored. When the computer-readable storage medium is run on a computer, the computer can execute the method described in the first or second aspect above.

[0079] In an eighth aspect, a computer program product comprising instructions is provided, which, when executed on a computer, enables the computer to execute the method described in any one of the first or second aspects above.

[0080] Among them, the technical effects brought about by any possible implementation method of the second to eighth aspects can be referred to the technical effects brought about by the above-mentioned first aspect or different implementation methods of the first aspect, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0081] FIG1 is a schematic diagram of the architecture of a communication system provided in an embodiment of the present application;

[0082] FIG2 is a first structural diagram of a communication device provided in an embodiment of the present application;

[0083] FIG3 is a flowchart of a synchronization signal transmission method provided in an embodiment of the present application;

[0084] FIG4 is a schematic diagram of a correspondence relationship between a precoder and subsequence groups provided in an embodiment of the present application;

[0085] FIG5A is a schematic diagram of the correspondence between another precoder and subsequence grouping according to an embodiment of the present application;

[0086] FIG5B is a schematic diagram of a correspondence between another precoder and subsequence grouping according to an embodiment of the present application;

[0087] FIG6 is a second structural diagram of a communication device provided in an embodiment of the present application;

[0088] FIG7 is a third structural diagram of the communication device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0089] In order to facilitate understanding of the technical solutions of the embodiments of the present application, a brief introduction to the relevant technologies or terms of the present application is first given as follows.

[0090] First, the application scenarios of sequences.

[0091] A sequence can be an ordered set of numbers or elements. In different scenarios, specific sequences can leverage their structure and properties to achieve specific functions. The following describes the application scenarios and functions of sequences.

[0092] In a communication system, a terminal device needs to access the network after powering on. However, the terminal device does not have prior knowledge of the network and cannot properly receive information from network devices. Therefore, the terminal device first needs to perform a network search and determine information such as timing information and the frequency resources used by the network. To enable the terminal device to obtain this information, the network device can periodically send a synchronization signal carried on a synchronization channel to the terminal device. The synchronization signal can be generated based on a predefined sequence or one of multiple sequences, and the sequence included in the synchronization signal is referred to as the synchronization sequence. Accordingly, the terminal device can search for the synchronization signal at multiple preset frequency points based on the predefined synchronization sequence or any received synchronization sequence. Once the terminal device has found the synchronization signal, it has successfully found the network. The terminal device can then perform time synchronization, as well as frequency offset estimation and compensation, to subsequently receive system broadcast information and other signals. It can be seen that the sequence plays a vital role in the initial synchronization process. Furthermore, the sequence detection performance, as well as its ability to resist frequency offset, interference, and noise, determines whether the terminal device can successfully access the network and the speed at which it can do so. The sequence detection performance can be characterized by sequence correlation.

[0093] Since the above-mentioned synchronization signal is sent by the network device to the terminal device, the above-mentioned synchronization signal can also be called a downlink synchronization signal, and the above-mentioned synchronization process can also be called uplink synchronization. In addition to downlink synchronization, the sequence can also be applied to uplink synchronization. Specifically, after obtaining the information required to access the network, the terminal device can attempt to communicate with the network device to notify the network device of its existence and cooperate with the network device to complete the subsequent access process. Similar to downlink synchronization, the terminal device can send an uplink synchronization signal on a reserved random access resource. The uplink synchronization signal may include an uplink synchronization sequence. Accordingly, the network device will detect the uplink synchronization signal on each reserved random access resource to know whether there is a terminal device requesting to access the network. While detecting the uplink synchronization signal, the network device will also estimate the uplink timing advance parameter and send the estimation result to the terminal device. The terminal device can adjust the timing of its own uplink transmission based on the estimation result, so that the uplink transmission of multiple terminal devices can achieve synchronization at the frame, subframe, time slot or symbol level. It can be seen that the sequence detection performance, as well as the ability to resist frequency offset, interference and noise, also determines the uplink random access request detection performance and the uplink timing advance parameter estimation performance.

[0094] In addition to synchronization, sequences can also be used in multiple access systems. For example, code division multiple access (CDMA) can use sequences as spreading codes, with different terminal devices using different spreading codes. Because spreading codes can be orthogonal, a network device using the spreading code of a particular terminal device during reception can eliminate the influence of information from other terminal devices, thereby successfully receiving information from that specific terminal device. Similarly, in resource reuse and information transmission scenarios, such as pilot multiplexing, sequences can be used as a means of code division. As can be seen, sequence correlation can affect the performance of multiple access systems.

[0095] Sequences can also be used in the design of low peak-to-average power ratio (PAPR) signals. For communication systems that use orthogonal frequency division multiplexing (OFDM) or similar frequency-domain modulation as waveforms, one important factor to consider is the PAPR of the signal, particularly uplink signals, including the PAPR of uplink random access signals and / or uplink pilot signals. In such communication systems, the characteristics of specific sequences can be utilized to design low PAPR signals.

[0096] In future communication systems, such as sixth-generation (6G) mobile communication systems, the integration of communication and perception will be a key new feature. In research on the integration of perception and communication, sequence can influence the implementation and performance of perception functions. Specifically, during wireless transmission, signals experience delays due to transmission distance and frequency offsets, known as Doppler shifts, due to the relative motion between the transmitter and receiver. The target to be detected can transmit a specific sequence known to both the transmitter and receiver. Accordingly, the receiver can detect the delay and Doppler shift of the received specific sequence transmitted through the channel relative to the specific sequence, thereby calculating the distance and velocity information of the target to be detected. To achieve good perception performance, the specific sequence must have good ambiguity function performance. Specifically, the correlation value of the specific sequence has a peak at locations corresponding to the correct delay and / or Doppler shift, and has low sidelobes at locations corresponding to incorrect delay and / or Doppler shifts.

[0097] In addition to the aforementioned application scenarios, sequences are also widely used in communication systems for scrambling, encryption, and codebook generation in precoding. In summary, future research on sequences will focus on achieving superior performance in solving classic problems while also proposing novel sequence designs and expanding into new application scenarios. Because existing systems have numerous and complex definitions of sequences and lack a systematic definition method, there is an urgent need to develop systematic, multi-functional sequence generation methods for future communication systems that are applicable to a wide range of scenarios.

[0098] Second, the existing synchronization signal transmission method.

[0099] In one possible implementation, the synchronization signal including the PSS and SSS may be sent in a synchronization signal and physical broadcast channel block (synchronization signal and PBCH block, SSB).

[0100] In LTE networks, the PSS or SSS transmission period can be 5 milliseconds (ms), and the PBCH transmission period can be 10 ms. The PSS includes a synchronization sequence of length 63, and the SSS includes two synchronization sequences of length 31. The PBCH can occupy 6 resource blocks (RBs).

[0101] In an NR network, the period of SSB transmission for initial access may be 20 ms. The synchronization sequence included in the PSS may be a maximum linear shift register sequence of length 127, and the synchronization sequence included in the SSS may be a Gold sequence of length 127. The maximum linear shift register sequence (maximum length linear shift register sequence) may also be referred to as an m-sequence.

[0102] PSS and SSS can occupy 12 RBs each, and PBCH can occupy 20 RBs. In NR networks, SSBs can include PSS, SSS, and PBCH.

[0103] The PSS or SSS sent by the base station to the UE includes a synchronization sequence. As described in the background technology, the base station uses a precoder to send signals only after sending the synchronization signal including the PSS and / or SSS to the UE. This results in the transmission quality of the synchronization signal not being guaranteed.

[0104] In order to ensure the transmission quality of the synchronization signal, in an embodiment of the present application, the network device may precode multiple subsequences according to subsequence grouping, thereby improving the transmission quality of the synchronization signal by introducing precoding in advance.

[0105] The technical solutions in the embodiments of the present application will be described below in conjunction with the drawings in the embodiments of the present application. Among them, in the description of the present application, unless otherwise specified, " / " indicates that the objects associated before and after are in an "or" relationship, for example, A / B can represent A or B; "and / or" in the present application is only a description of the associated relationship of associated objects, indicating that there can be three relationships, for example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone, where A and B can be singular or plural. In addition, in the description of the present application, unless otherwise specified, "multiple" refers to two or more than two. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, or c can represent: a, b, c, ab, ac, bc, or abc, where a, b, c can be single or multiple. In addition, in order to facilitate the clear description of the technical solutions of the embodiments of the present application, in the embodiments of the present application, words such as "first" and "second" are used to distinguish between identical or similar items with substantially the same functions and effects. Those skilled in the art will understand that words such as "first" and "second" do not limit the quantity and execution order, and words such as "first" and "second" do not necessarily limit differences. At the same time, in the embodiments of the present application, words such as "exemplary" or "for example" are used to indicate examples, illustrations or explanations. Any embodiment or design described as "exemplary" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or design schemes. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a concrete way for easy understanding.

[0106] Figure 1 is a schematic diagram of the architecture of a communication system 1000 used in an embodiment of the present application. As shown in Figure 1 , the communication system includes a radio access network 100 and a core network 200. Optionally, the communication system 1000 may also include the Internet 300. The radio access network 100 may include at least one radio access network device (such as 110a and 110b in Figure 1 ) and at least one terminal device (such as 120a-120j in Figure 1 ). The terminal device is wirelessly connected to the radio access network device, and the radio access network device is wirelessly or wiredly connected to the core network. The core network device and the radio access network device may be independent and distinct physical devices, or the functions of the core network device and the logical functions of the radio access network device may be integrated into the same physical device, or a single physical device may integrate some of the functions of the core network device and some of the functions of the radio access network device. Terminal devices and radio access network devices may be connected to each other via wired or wireless means. FIG1 is only a schematic diagram. The communication system may further include other network devices, such as wireless relay devices and wireless backhaul devices, which are not shown in FIG1 .

[0107] Radio access network equipment is the access device that terminal devices use to access the communication system wirelessly. Radio access network equipment can be a base station, an evolved NodeB (eNodeB), a transmission reception point (TRP), a next-generation NodeB (gNB) in a fifth-generation (5G) mobile communication system, a next-generation base station in a 6G mobile communication system, a base station in a future mobile communication system, or an access node in a WiFi system. In another possible scenario, multiple radio access network (RAN) nodes collaborate to assist the terminal in achieving wireless access, with different RAN nodes implementing part of the base station's functions. For example, a RAN node can be a centralized unit (CU), a distributed unit (DU), a CU-control plane (CP), a CU-user plane (UP), or a radio unit (RU). The CU and DU can be set up separately, or they can be included in the same network element, such as the baseband unit (BBU). The RU may be included in a radio frequency device or a radio frequency unit, for example, in a remote radio unit (RRU), an active antenna unit (AAU) or a remote radio head (RRH).

[0108] In different systems, CU (or CU-CP and CU-UP), DU or RU may also have different names, but those skilled in the art can understand their meanings. For example, in an open RAN (ORAN) system, CU may also be called O-CU (open CU), DU may also be called O-DU, CU-CP may also be called O-CU-CP, CU-UP may also be called O-CU-UP, and RU may also be called O-RU. For the convenience of description, this application uses CU, CU-CP, CU-UP, DU and RU as examples for description. Any unit of CU (or CU-CP, CU-UP), DU and RU in this application may be implemented by a software module, a hardware module, or a combination of a software module and a hardware module. The embodiments of the present application may be implemented by a DU or a RU.

[0109] The wireless access network device can be a macro base station (such as 110a in Figure 1), a micro base station or an indoor station (such as 110b in Figure 1), a relay node, a donor node, etc. The embodiments of this application do not limit the specific technology and device form used by the wireless access network device. For ease of description, the following description uses a base station as an example of a wireless access network device.

[0110] A terminal device is a device with wireless transceiver capabilities that can send signals to a base station or receive signals from a base station. A terminal device may also be referred to as a terminal, user equipment (UE), mobile station, mobile terminal device, etc. Terminal devices can be widely used in various scenarios, such as device-to-device (D2D), vehicle-to-everything (V2X) communication, machine-type communication (MTC), Internet of Things (IoT), virtual reality, augmented reality, industrial control, autonomous driving, telemedicine, smart grid, smart furniture, smart office, smart wearable, smart transportation, smart city, etc. A terminal device may be a mobile phone, tablet computer, computer with wireless transceiver capabilities, wearable device, vehicle, drone, helicopter, airplane, ship, robot, robotic arm, smart home device, etc. The embodiments of this application do not limit the specific technology and specific device form adopted by the terminal device.

[0111] Base stations and terminal devices can be fixed or mobile. They can be deployed on land, indoors or outdoors, handheld or vehicle-mounted; on water; or on aircraft, balloons, and satellites. The embodiments of this application do not limit the application scenarios of base stations and terminal devices.

[0112] The roles of base stations and terminal devices can be relative. For example, the helicopter or drone 120i in Figure 1 can be configured as a mobile base station. For terminal devices 120j accessing the wireless access network 100 via 120i, terminal device 120i is a base station. However, for base station 110a, 120i is a terminal device, meaning that communication between 110a and 120i occurs via a wireless air interface protocol. Of course, communication between 110a and 120i can also occur via a base station-to-base station interface protocol. In this case, 120i is also a base station relative to 110a. Therefore, base stations and terminal devices can be collectively referred to as communication devices. 110a and 110b in Figure 1 can be referred to as communication devices with base station functionality, and 120a-120j in Figure 1 can be referred to as communication devices with terminal functionality.

[0113] Communication between base stations and terminal devices, between base stations, and between terminal devices can be carried out through authorized spectrum, unauthorized spectrum, or both; communication can be carried out through spectrum below 6 gigahertz (GHz), spectrum above 6 GHz, or spectrum below 6 GHz and spectrum above 6 GHz. The embodiments of the present application do not limit the spectrum resources used for wireless communication.

[0114] Functions such as synchronization, channel estimation, and perception can be achieved between the base station and the terminal device through sequences. In the embodiment of the present application, the synchronization signal sent by the base station to the terminal device may include a synchronization sequence. Accordingly, the terminal device can achieve downlink synchronization based on the partial or complete synchronization signal received from the base station. Synchronization can be understood as the process of establishing time synchronization and / or frequency synchronization between the base station and the terminal device. Specifically, the transmitting end can send a specific sequence, namely the synchronization sequence. The receiving end can detect this specific sequence. Afterwards, the receiving end can adjust its own timing according to the time of the detected specific sequence, and / or the receiving end can adjust its own carrier frequency according to the frequency of the detected specific sequence. Alternatively, the receiving end can then notify the transmitting end to adjust the timing and / or carrier frequency. For the downlink, the transmitting end can be the base station and the receiving end can be the terminal device. For the uplink, the transmitting end can be the terminal device and the receiving end can be the base station.

[0115] In the embodiments of the present application, the functions of the base station may also be performed by a module (such as a chip) in the base station, or by a control subsystem that includes the base station functions. The control subsystem that includes the base station functions here may be a control center in the above-mentioned application scenarios such as smart grid, industrial control, smart transportation, and smart city. The functions of the terminal device may also be performed by a module (such as a chip or a modem) in the terminal device, or by a device that includes the terminal device functions.

[0116] In this application, a base station sends downlink signals or downlink information to a terminal device, and the downlink information is carried on a downlink channel; the terminal device sends uplink signals or uplink information to the base station, and the uplink information is carried on an uplink channel. In order to communicate with the base station, the terminal device needs to establish a wireless connection with the cell controlled by the base station. The cell with which the terminal device has established a wireless connection is called the serving cell of the terminal device. When the terminal device communicates with the serving cell, it will also be interfered with by signals from neighboring cells.

[0117] Exemplarily, the network device 110 provided in the embodiment of the present application may be 110a or 110b in FIG. 1 , and the terminal device 120 provided in the embodiment of the present application may be any one of 120a - 120j in FIG. 1 .

[0118] Optionally, the relevant functions of the terminal device or network device in the embodiments of the present application can be implemented by a single device, or by multiple devices, or by one or more functional modules within a single device, and the embodiments of the present application do not specifically limit this. It is understood that the above functions can be network elements in hardware devices, software functions running on dedicated hardware, a combination of hardware and software, or virtualized functions instantiated on a platform (e.g., a cloud platform).

[0119] For example, the relevant functions of the terminal device or network device in the embodiment of the present application can be implemented by the communication device 20 in Figure 2.

[0120] Figure 2 is a schematic diagram of the structure of a communication device 20 provided in an embodiment of the present application. The communication device 20 includes one or more processors 201, a communication circuit 202, and at least one communication interface (Figure 2 is merely an example of a communication interface 204 and a processor 201), and may optionally include a memory 203.

[0121] The processor 201 may be a CPU, a microprocessor, an application-specific integrated circuit (ASIC), or one or more integrated circuits for controlling the execution of the program of the present application.

[0122] The communication line 202 may include pathways for connecting different components.

[0123] Communication interface 204 can be a transceiver module for communicating with other devices or communication networks, such as Ethernet, RAN, WLAN, etc. For example, the transceiver module can be a device such as a transceiver or a transceiver. Alternatively, communication interface 204 can be a transceiver circuit located within processor 201, used to implement signal input and output to the processor.

[0124] The memory 203 may be a device having a storage function. For example, it may be a read-only memory (ROM) or other types of static storage devices that can store static information and instructions, a random access memory (RAM) or other types of dynamic storage devices that can store information and instructions, or an electrically erasable programmable read-only memory (EEPROM), a compact disc read-only memory (CD-ROM) or other optical disc storage, optical disc storage (including compact discs, laser discs, optical discs, digital versatile discs, Blu-ray discs, etc.), a magnetic disk storage medium or other magnetic storage device, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and can be accessed by a computer, but is not limited thereto. The memory may exist independently and be connected to the processor via the communication line 202. The memory may also be integrated with the processor.

[0125] The memory 203 is used to store computer-executable instructions for executing the solution of the present application, and the execution is controlled by the processor 201. The processor 201 is used to execute the computer-executable instructions stored in the memory 203, thereby implementing the synchronization signal transmission method provided in the embodiment of the present application.

[0126] Alternatively, in an embodiment of the present application, the processor 201 may also perform processing-related functions in the synchronization signal transmission method provided in the following embodiments of the present application, and the communication interface 204 is responsible for communicating with other devices or communication networks, which is not specifically limited in the embodiments of the present application.

[0127] The computer-executable instructions in the embodiments of the present application may also be referred to as application code, which is not specifically limited in the embodiments of the present application.

[0128] In a specific implementation, as an embodiment, the processor 201 may include one or more CPUs, such as CPU0 and CPU1 in FIG. 2 .

[0129] In a specific implementation, as an embodiment, the communication device 20 may include multiple processors, such as processor 201 and processor 207 in Figure 2. Each of these processors may be a single-core (single-CPU) processor or a multi-core (multi-CPU) processor. The processor here may refer to one or more devices, circuits, and / or processing cores for processing data (e.g., computer program instructions).

[0130] In a specific implementation, as an embodiment, the communication apparatus 20 may further include an output device 205 and an input device 206. The output device 205 communicates with the processor 201 and may display information in a variety of ways.

[0131] The communication device 20 can be a general-purpose device or a dedicated device. For example, the communication device 20 can be a desktop computer, a portable computer, a network server, a personal digital assistant (PDA), a mobile phone, a tablet computer, a wireless terminal device, an in-vehicle terminal device, an embedded device, or a device having a similar structure to that shown in FIG2 . The embodiments of the present application do not limit the type of the communication device 20.

[0132] The following will describe in detail the synchronization signal transmission method provided in the embodiment of the present application with reference to FIG1 and FIG2 .

[0133] As shown in FIG3 , a synchronization signal transmission method provided in an embodiment of the present application includes the following steps:

[0134] Step S301: The network device precodes a plurality of subsequences included in a synchronization sequence according to a correspondence between precoders and subsequence groups.

[0135] The first subsequence among the multiple subsequences is precoded using a precoder corresponding to the subsequence group to which the first subsequence belongs.

[0136] For example, the synchronization sequence in the embodiment of the present application may be a PSS sequence or an SSS sequence. The subsequence group in the embodiment of the present application may be a part of a synchronization sequence included in the PSS or SSS.

[0137] The multiple subsequences in the embodiment of the present application may constitute a synchronization sequence included in a synchronization signal in an existing synchronization signal transmission method. In the embodiment of the present application, each subsequence may be mapped to multiple subcarriers of OFDM in the frequency domain.

[0138] Optionally, the number of subsequences included in the synchronization sequence is the same as the length of each subsequence included in the synchronization sequence. In this solution, the synchronization sequence can be equally divided into K subsequences, that is, the number of subsequences included in the synchronization signal can be represented as K. The length of the subsequence can be represented as N. For example, K = N = 11. Simulation results show that in this solution, the subsequences have good ambiguity function performance. Specifically, the correlation value of the sequence has lower sidelobes corresponding to erroneous delay and / or Doppler frequency offset.

[0139] In the embodiment of the present application, the values ​​of K and N may also be different. In addition, the lengths of the multiple subsequences included in the synchronization signal may also be different, that is, the synchronization sequence may be divided into K subsequences, and the lengths of at least two subsequences in the K subsequences are different. This embodiment of the present application does not impose any limitation on this.

[0140] Optionally, the subsequence included in the synchronization signal is a longest linear shift register sequence or a multi-phase sequence.

[0141] Optionally, the first subsequence included in the synchronization signal is a multi-phase sequence; the general term of the first subsequence satisfies the following formula (1):

[0142] Where a, b, c, d, p, and q are constants; n = 1, 2, ..., N, where N represents the length of the first subsequence and is a positive integer; k = 1, 2, ..., K, where K represents the number of subsequences included in the synchronization signal and is a positive integer. In particular, if p = 3 and q = 2, then the above formula (1) can be expressed as formula (2):

[0143] Optionally, each subsequence included in the synchronization sequence occupies the same time domain resources, or each subsequence included in the synchronization sequence occupies the same frequency domain resources. In this scheme, the multiple subsequences included in the synchronization sequence can be mapped to multiple consecutive subcarriers of OFDM. Alternatively, the multiple subsequences included in the synchronization sequence can be mapped to multiple consecutive OFDM symbols, and each subsequence can be mapped to multiple consecutive subcarriers of OFDM. The embodiments of the present application do not impose any restrictions on this. When each subsequence included in the synchronization sequence occupies the same frequency domain resources, for terminal devices, especially the second type of terminal devices, the synchronization sequence may not be limited by bandwidth, so that the synchronization sequence can include more subsequences, or the synchronization sequence can carry more information.

[0144] Optionally, the total length of the subsequences contained in the subsequence group is an integer multiple of the first preset value. The first preset value in the embodiment of the present application can be the number of subcarriers contained in the minimum precoding resource block group (PRG), so that the scheme can be compatible with the parameter settings in the existing precoding technology. Assuming that the minimum PRG is two RBs, since each RB contains 12 subcarriers in the frequency domain, the first preset value can be 24.

[0145] Assuming that the synchronization sequence includes 12 subsequences of 12 bits in length, the 12 subsequences can be divided into 2 subsequence groups, each of which includes 6 subsequences of 12 bits in length, that is, the length of each subsequence group is 72 bits, which is 3 times 24. Alternatively, the 12 subsequences can be divided into 3 subsequence groups, each of which includes 4 subsequences of 12 bits in length, that is, the length of each subsequence group is 48 bits, which is 2 times 24. Alternatively, the 12 subsequences can be divided into 6 subsequence groups, each of which includes 2 subsequences of 12 bits in length, that is, the length of each subsequence group is 24 bits, which is 1 times 24.

[0146] Optionally, the total length of the subsequences contained in the subsequence group is an integer multiple of a second preset value, wherein the total length of the subsequences contained in the subsequence group is obtained by padding. This embodiment of the present application does not impose any restrictions on the padding method. The second preset value in this embodiment of the present application can be less than or equal to the first preset value. In other words, this solution can overcome the minimum PRG limitation in existing precoding technologies. The second preset value can be, for example, 12 or 24. The following description uses the second preset value of 12 as an example.

[0147] Optionally, the total length of the subsequences contained in the subsequence group may not be an integer multiple of the second preset value. Assuming that the synchronization sequence includes 11 subsequences with a length of 11 bits, then the 11 subsequences can be divided into 11 subsequence groups, each of which can include 1 subsequence with a length of 11 bits, that is, the length of each subsequence group is 11 bits, which is not an integer multiple of 12. Alternatively, the 11 subsequences can be divided into 11 subsequence groups, and the length of each subsequence group can be extended to 12 by padding, such as padding with 0 or cycling padding.

[0148] For example, the synchronization sequence may include six subsequences, each of which may be six bits long. The first subsequence group may include one subsequence with a length of six bits; the second subsequence group may include two subsequences with a length of 12 bits; and the third subsequence group may include three subsequences with a length of 18 bits. Since the lengths of the first and third subsequences are 6 and 18, respectively, which are not integer multiples of 12, the lengths of the first and third subsequences may be extended to 12 and 24, respectively. Alternatively, the subsequences may be grouped according to integer multiples of 12, for example, two subsequences may be grouped together, and the length of each subsequence group may be 12 bits.

[0149] In the embodiment of the present application, one subsequence group may correspond to one encoder.

[0150] Optionally, the correspondence between the precoders and the subsequence groups includes: the precoders corresponding to each M subsequence groups constitute the same precoder set, and the precoder set includes M different precoders, M is a positive integer, 1<M<K, K represents the number of subsequence groups, and K is a positive integer. In this solution, the network device uses multiple precoders, and can select a precoder with better reception performance for subsequent network devices to transmit signals to terminal devices. The embodiment of the present application does not impose any restrictions on the order of the precoders corresponding to each M subsequence group. The order of the precoders corresponding to each M subsequence group can be the same or different.

[0151] For example, assuming that the subsequence is divided into 11 subsequence groups, the precoder set consisting of the precoders corresponding to every three subsequence groups can be {precoder 1, precoder 2, precoder 3}. Different precoder indices indicate different precoders. The precoders corresponding to the remaining two subsequence groups can be any two of precoder 1, precoder 2, or precoder 3.

[0152] Optionally, the precoders corresponding to each M subsequence groups constitute the same precoder set, including: the precoders corresponding to each M subsequence groups are the same. In this scheme, the order of the precoders corresponding to each M subsequence group can be the same. Exemplarily, assuming that the subsequence is divided into 9 subsequence groups, K=9, M=3, then the 1st, 2nd, and 3rd subsequence groups can correspond to precoder 2, precoder 3, and precoder 1, respectively; the 4th, 5th, and 6th subsequence groups can also correspond to precoder 2, precoder 3, and precoder 1, respectively; the 7th, 8th, and 9th subsequence groups can also correspond to precoder 2, precoder 3, and precoder 1, respectively.

[0153] Optionally, the precoders corresponding to every M subsequence groups constitute the same precoder set, including: the precoder index value is the remainder obtained by dividing the subsequence group index value by M. Exemplarily, assuming that the subsequence is divided into 11 subsequence groups, K=11, and M=3, then the 1st, 4th, 7th, and 10th subsequence groups can correspond to precoder 1; the 2nd, 5th, 8th, and 11th subsequence groups can correspond to precoder 2; and the 3rd, 6th, and 9th subsequence groups can correspond to precoder 3.

[0154] Exemplarily, Figure 4 is a schematic diagram of the correspondence between a precoder and a subsequence group. The synchronization sequence may include 11 subsequences of 11 bits in length. The 11 subsequences may be divided into 11 subsequence groups, each of which may include 1 subsequence of 11 bits in length. Each subsequence or each subsequence group may be carried on 11 consecutive subcarriers, and each subsequence or each subsequence group corresponds to a precoder. Specifically, the 1st, 4th, 7th and 10th subsequences may correspond to precoder 1; the 2nd, 5th, 8th and 11th subsequences may correspond to precoder 2; and the 3rd, 6th and 9th subsequences may correspond to precoder 3. The subsequences in Figure 4 may be PSS subsequences or SSS subsequences.

[0155] Optionally, the correspondence between the precoders and the subsequence groups includes: the precoders corresponding to each subsequence group are different.

[0156] In conjunction with Figure 4, Figure 5A is a schematic diagram of the correspondence between another precoder and subsequence grouping. Among them, the synchronization sequence may include 11 subsequences with a length of 11 bits. The 11 subsequences can be divided into 11 subsequence groups, each of which may include 1 subsequence with a length of 11 bits. Each subsequence or each subsequence group may be carried on 11 consecutive subcarriers, and each subsequence or each subsequence group corresponds to a precoder. Unlike Figure 4, in Figure 5A, the i-th subsequence may correspond to precoder i, i = 1, 2, ..., 11. The subsequence in Figure 5A may be a PSS subsequence or an SSS subsequence.

[0157] In conjunction with Figure 5A, Figure 5B is a schematic diagram of another correspondence between precoders and subsequence groups. Similar to Figure 5A, the precoders corresponding to each subsequence group are different. Specifically, in Figure 5B, the i-th subsequence can correspond to precoder i, i = 1, 2, ..., 5. Different from Figure 5A, the subsequences are grouped differently in Figure 5B. Specifically, the first subsequence group can include subsequence 1 and subsequence 2; the second subsequence group can include subsequence 3 and subsequence 4; the third subsequence group can include subsequence 5 and subsequence 6; the fourth subsequence group can include subsequence 7 and subsequence 8; the fifth subsequence group can include subsequence 9 and subsequence 10; and the sixth subsequence group can include subsequence 11. The subsequences in Figure 5B can be PSS subsequences or SSS subsequences.

[0158] It should be noted that Figure 5B only shows an example of grouping 11 subsequences. In fact, other grouping methods can also be used, and the embodiments of the present application do not impose any restrictions on this. For example, the fifth subsequence group can include subsequence 9, subsequence 10, and subsequence 11, and the sixth subsequence group does not exist. In addition, the correspondence between the precoder and the subsequence group in Figure 5B can also adopt the correspondence between the precoder and the subsequence group in Figure 4. That is, the first and fourth subsequence groups can correspond to precoder 1; the second and fifth subsequence groups can correspond to precoder 2; and the third and sixth subsequence groups can correspond to precoder 3; the embodiments of the present application do not impose any restrictions on this.

[0159] Optionally, the precoder corresponding to any subsequence group corresponds to one codeword from K codewords selected from the precoding matrix, where K represents the number of subsequence groups and is a positive integer.

[0160] In the embodiment of the present application, one precoder may correspond to one codeword, or the precoder and the codeword may have a one-to-one correspondence, or one precoder may be associated with one codeword.

[0161] Optionally, K is less than or equal to N, where N represents the number of antennas and is a positive integer, and the K codewords are mutually orthogonal. This solution can achieve diversity gain through the design of multiple antennas.

[0162] Exemplarily, when K=3 and N=4, precoder 6, precoder 8, and precoder 9 may be selected.

[0163] Optionally, K is greater than N, where N represents the number of antennas and is a positive integer. The K codewords include N mutually orthogonal codewords, and the mutual correlation between the K codewords is minimum.

[0164] Exemplarily, when K=6 and N=4, encoder 0, precoder 1, precoder 2, precoder 3, precoder 20, and precoder 22 may be selected.

[0165] Step S302: The network device sends a synchronization signal to the terminal device, wherein the synchronization signal includes a plurality of precoded subsequences.

[0166] Optionally, the synchronization signal transmission method provided in an embodiment of the present application further includes: the terminal device sending first information to the network device. The first information carries the index of the first precoder and / or the index of the first subsequence group; the first subsequence group corresponds to the first precoder, and the first precoder is used for signal precoding. Accordingly, the network device receives the first information from the terminal device. In this solution, the terminal device can select a first precoder with better reception performance and feed it back to the network device, so that the network device can subsequently use the first precoder to improve transmission quality when transmitting signals to the terminal device.

[0167] Specifically, the first precoder is used by the network device to precode the signal sent to the terminal device.

[0168] Exemplarily, the first precoder may be used by the network device to precode a random access response (RAR) and / or message (MSG) 4 sent to the terminal device.

[0169] When the terminal device is a first type of terminal device, the following step S303 is performed:

[0170] Step S303: The terminal device receives a synchronization signal from the network device and performs downlink synchronization according to the synchronization signal.

[0171] Alternatively, when the terminal device is a second type of terminal device, the following step S304 is performed:

[0172] Step S304: The terminal device receives one or more precoded subsequences in a synchronization signal from the network device, and performs downlink synchronization according to the one or more precoded subsequences in the synchronization signal.

[0173] The bandwidth of the signal received by the first type of terminal device is wider than the bandwidth of the signal received by the second type of terminal device.

[0174] Exemplarily, the first type of terminal device in the embodiment of the present application may be a broadband terminal device, and the second type of terminal device in the embodiment of the present application may be a narrowband terminal device, such as a narrowband Internet of Things (NB-IoT) terminal device.

[0175] In the synchronization signal transmission method provided in the embodiment of the present application, the network device can precode the subsequences according to the subsequence grouping, thereby introducing a precoder to improve the transmission quality of the synchronization signal, thereby enabling the terminal device to achieve downlink synchronization faster and more accurately. In addition, the broadband terminal device can receive a complete synchronization signal including multiple precoded subsequences, and the narrowband terminal device can receive a partial synchronization signal including one or more precoded subsequences. For broadband terminal devices and narrowband terminal devices, the embodiment of the present application can adopt the same synchronization signal transmission structure, thereby reducing the complexity of the cellular network system design and achieving the technical effect of saving time and frequency resources.

[0176] It can be understood that in the above embodiments, the methods and / or steps implemented by the network device can also be implemented by components (such as chips or circuits) that can be used for the network device or an apparatus including the network device; the methods and / or steps implemented by the terminal device can also be implemented by components (such as chips or circuits) that can be used for the terminal device or an apparatus including the terminal device.

[0177] It is understandable that, in order to implement the above functions, the network device or terminal device includes a hardware structure and / or software module that performs the corresponding functions. Those skilled in the art should easily realize that, in combination with the units and algorithm steps of each example described in the embodiments disclosed herein, the present application can be implemented in the form of hardware or a combination of hardware and computer software. Whether a function is executed in a hardware or computer software-driven hardware manner depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0178] In the embodiment of the present application, the network device or terminal device can be divided into functional modules according to the above method embodiment. For example, each functional module can be divided according to each function, or two or more functions can be integrated into one processing module. The above integrated modules can be implemented in the form of hardware or in the form of software functional modules. It should be noted that the division of modules in the embodiment of the present application is schematic and is only a logical functional division. In actual implementation, there may be other division methods.

[0179] For example, the network device in the embodiment of the present application can be implemented in the form of a communication device 600 shown in Figure 6. The communication device 600 may include a precoding module 601 and a transceiver module 602. The communication device 600 is used to implement the functions of the network device in the method embodiments shown in Figures 3 to 5B above.

[0180] Exemplarily, when the communication device 600 is used to implement the functions of the network device in the method embodiment shown in Figure 3: the precoding module 601 is used to precode multiple subsequences included in the synchronization sequence according to the correspondence between the precoder and the subsequence grouping; the transceiver module 602 sends a synchronization signal.

[0181] For a more detailed description of the above-mentioned precoding module 601 and transceiver module 602, reference may be made to the relevant descriptions in the method embodiments shown in FIG. 3 to FIG. 5B .

[0182] For another example, the terminal device in the embodiment of the present application can be implemented in the form of a communication device 700 shown in Figure 7. The communication device 700 may include a transceiver module 701 and a synchronization module 702. The communication device 700 is used to implement the functions of the terminal device in the method embodiments shown in Figures 3 to 5B above.

[0183] Exemplarily, when the communication device 700 is used to implement the functions of the terminal device in the method embodiment shown in Figure 3: when the terminal device is a first type of terminal device, the transceiver module 701 is used to receive a synchronization signal; the synchronization module 702 is used to perform downlink synchronization according to the synchronization signal; or, when the terminal device is a second type of terminal device, the transceiver module 701 is used to receive one or more precoded subsequences in the synchronization signal; the synchronization module 702 is used to perform downlink synchronization according to one or more precoded subsequences in the synchronization signal.

[0184] For a more detailed description of the above-mentioned transceiver module 701 and synchronization module 702, reference may be made to the relevant descriptions in the method embodiments shown in FIG. 3 to FIG. 5B .

[0185] In this embodiment, the communication device 600 or the communication device 700 may be presented in the form of various functional modules in an integrated manner. The "module" here may refer to a specific ASIC, circuit, processor and memory that executes one or more software or firmware programs, integrated logic circuit, and / or other devices that can provide the above functions.

[0186] In a simple embodiment, those skilled in the art may appreciate that the communication device 600 may take the form of the communication device 20 shown in FIG. 2 .

[0187] For example, the processor 201 and / or the processor 207 in the communication device 20 shown in FIG2 can call the computer-executable instructions stored in the memory 203 to enable the communication device 20 to execute the synchronization signal transmission method in the above-mentioned method embodiment. Specifically, part of the functions / implementation process of the precoding module 601 in FIG6 can be implemented by the processor 201 and / or the processor 207 in the communication device 20 shown in FIG2 calling the computer-executable instructions stored in the memory 203; part of the functions / implementation process of the transceiver module 602 in FIG6 can be implemented by a communication module connected via the communication interface 204 in FIG2.

[0188] In a simple embodiment, those skilled in the art may appreciate that the communication device 700 may take the form of the communication device 20 shown in FIG. 2 .

[0189] For example, the processor 201 and / or the processor 207 in the communication device 20 shown in FIG2 can call the computer-executable instructions stored in the memory 203 to enable the communication device 20 to execute the synchronization signal transmission method in the above-mentioned method embodiment. Specifically, part of the functions / implementation process of the transceiver module 701 in FIG7 can be implemented by a communication module connected via the communication interface 204 in FIG2. Part of the functions / implementation process of the synchronization module 702 in FIG7 can be implemented by the processor 201 and / or the processor 207 in the communication device 20 shown in FIG2 calling the computer-executable instructions stored in the memory 203.

[0190] Since the communication device 600 and the communication device 700 provided in this embodiment can execute the above-mentioned method for transmitting a synchronization signal, the technical effects that can be obtained can refer to the above-mentioned method embodiments and will not be repeated here.

[0191] It should be noted that one or more of the above modules or units can be implemented by software, hardware, or a combination of the two. When any of the above modules or units is implemented by software, the software exists in the form of computer program instructions and is stored in a memory, and a processor can be used to execute the program instructions and implement the above method flow. The processor can be built into an SoC (system on chip) or an ASIC, or it can be an independent semiconductor chip. In addition to the core used to execute software instructions to perform calculations or processing within the processor, it can further include necessary hardware accelerators, such as a field programmable gate array (FPGA), a PLD (programmable logic device), or a logic circuit that implements dedicated logic operations.

[0192] When the above modules or units are implemented in hardware, the hardware can be any one or any combination of a CPU, a microprocessor, a digital signal processing (DSP) chip, a microcontroller unit (MCU), an artificial intelligence processor, an ASIC, a SoC, an FPGA, a PLD, a dedicated digital circuit, a hardware accelerator or a non-integrated discrete device, which can run the necessary software or not rely on the software to execute the above method flow.

[0193] Optionally, an embodiment of the present application further provides a chip system, comprising: at least one processor and an interface, wherein the at least one processor is coupled to a memory via the interface, and when the at least one processor executes a computer program or instruction in the memory, the method in any of the above method embodiments is executed. In one possible implementation, the communication device also includes a memory. Optionally, the chip system can be composed of a chip, or can include a chip and other discrete devices, which is not specifically limited in the embodiment of the present application.

[0194] In the above embodiments, all or part of the embodiments may be implemented by software, hardware, firmware, or any combination thereof. When implemented using a software program, all or part of the embodiments may be implemented in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of the present application are generated. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions may be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via a wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) method. The computer-readable storage medium may be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more media integrated therein. The available medium may be a magnetic medium (eg, a floppy disk, a hard disk, a magnetic tape), an optical medium (eg, a DVD), or a semiconductor medium (eg, a solid state disk (SSD)).

[0195] Although the present application is described herein in conjunction with various embodiments, in the process of implementing the claimed application, those skilled in the art can understand and implement other changes to the disclosed embodiments by reviewing the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other components or steps, and "a" or "an" does not exclude multiple situations. A single processor or other unit can implement several functions listed in the claims. Certain measures are recorded in different dependent claims, but this does not mean that these measures cannot be combined to produce good results.

[0196] Although the present application has been described with reference to specific features and embodiments thereof, it is apparent that various modifications and combinations may be made thereto without departing from the spirit and scope of the present application. Accordingly, this specification and the drawings are merely illustrative of the present application as defined by the appended claims and are deemed to cover any and all modifications, variations, combinations or equivalents within the scope of the present application. Obviously, those skilled in the art may make various modifications and variations to the present application without departing from the spirit and scope of the present application. Thus, the present application is intended to include such modifications and variations as fall within the scope of the claims of the present application and their equivalents.

Claims

1. A method for transmitting a synchronization signal, characterized in that: The method comprises: Precoding a plurality of subsequences included in a synchronization sequence according to a correspondence between a precoder and a subsequence group; wherein a first subsequence among the plurality of subsequences is precoded using a precoder corresponding to a subsequence group in which the first subsequence is located; A synchronization signal is sent, where the synchronization signal includes the multiple precoded subsequences.

2. The method according to claim 1, characterized in that: The total length of the subsequences contained in the subsequence group is an integer multiple of a first preset value.

3. The method according to claim 1, characterized in that: The total length of the subsequences contained in the subsequence group is an integer multiple of a second preset value, wherein the total length of the subsequences contained in the subsequence group is obtained by padding extension.

4. The method according to any one of claims 1 to 3, characterized in that: The correspondence between the precoders and the subsequence groups includes: the precoders corresponding to every M subsequence groups constitute the same precoder set, and the precoder set includes M different precoders, M is a positive integer, 1<M<K, K represents the number of subsequence groups, and K is a positive integer.

5. The method according to claim 4, characterized in that The precoders corresponding to each M subsequence groupings constitute the same precoder set, including: the precoders corresponding to each M subsequence groupings are the same.

6. The method according to any one of claims 1 to 3, characterized in that: The correspondence between the precoders and the subsequence groups includes: the precoders corresponding to each subsequence group are different from each other.

7. The method according to claim 6, characterized in that The precoder corresponding to any subsequence group corresponds to one codeword among K codewords selected from the precoding matrix, where K represents the number of subsequence groups and is a positive integer.

8. The method according to claim 7, characterized in that K is less than or equal to N, where N represents the number of antennas and is a positive integer, and the K codewords are orthogonal to each other.

9. The method according to claim 7, characterized in that: K is greater than N, where N represents the number of antennas and is a positive integer. The K codewords include N mutually orthogonal codewords, and the mutual correlation between the K codewords is minimal.

10. The method according to any one of claims 1 to 9, characterized in that: The method further comprises: First information is received, where the first information carries an index of a first precoder and / or an index of a first subsequence grouping; the first subsequence grouping corresponds to the first precoder, and the first precoder is used for signal precoding.

11. The method according to any one of claims 1 to 10, characterized in that: The number of subsequences included in the synchronization sequence is the same as the length of each subsequence included in the synchronization sequence.

12. The method according to claim 11, characterized in that The first subsequence included in the synchronization sequence is a multi-phase sequence; the general term of the first subsequence satisfies the following formula: Among them, a, b, c, d, p, q are constants; n=1, 2, ..., N, N represents the length of the first subsequence, and N is a positive integer; k=1, 2, ..., K, K represents the number of subsequences included in the synchronization sequence, and K is a positive integer.

13. The method according to claim 11 or 12, characterized in that: Each subsequence included in the synchronization sequence occupies the same time domain resources, or each subsequence included in the synchronization sequence occupies the same frequency domain resources.

14. A method for transmitting a synchronization signal, characterized in that: Applied to terminal equipment, including: In the case where the terminal device is a terminal device of the first type, receiving a synchronization signal, the synchronization signal including a plurality of precoded subsequences; performing downlink synchronization according to the synchronization signal; or, In the case where the terminal device is a terminal device of the second type, receiving one or more precoded subsequences in the synchronization signal; performing downlink synchronization according to the one or more precoded subsequences in the synchronization signal; Among them, the encoded subsequence is obtained by precoding multiple subsequences included in the synchronization sequence according to the correspondence between the precoder and the subsequence grouping, and the bandwidth of the signal received by the first type of terminal device is wider than the bandwidth of the signal received by the second type of terminal device.

15. The method according to claim 14, characterized in that The total length of the subsequences contained in the subsequence group is an integer multiple of a first preset value.

16. The method according to claim 14, characterized in that The total length of the subsequences contained in the subsequence group is an integer multiple of a second preset value, wherein the total length of the subsequences contained in the subsequence group is obtained by padding extension.

17. The method according to any one of claims 14 to 16, characterized in that: The correspondence between the precoders and the subsequence groups includes: the precoders corresponding to every M subsequence groups constitute the same precoder set, and the precoder set includes M different precoders, M is a positive integer, 1<M<K, K represents the number of subsequence groups, and K is a positive integer.

18. The method according to claim 17, characterized in that The precoders corresponding to each M subsequence groupings constitute the same precoder set, including: the precoders corresponding to each M subsequence groupings are the same.

19. The method according to any one of claims 14 to 16, characterized in that: The correspondence between the precoders and the subsequence groups includes: the precoders corresponding to each subsequence group are different from each other.

20. The method according to claim 19, characterized in that The precoder corresponding to any subsequence group corresponds to one codeword among K codewords selected from the precoding matrix, where K represents the number of subsequence groups and is a positive integer.

21. The method according to claim 20, characterized in that K is less than or equal to N, where N represents the number of antennas and is a positive integer, and the K codewords are orthogonal to each other.

22. The method according to claim 20, characterized in that K is greater than N, where N represents the number of antennas and is a positive integer. The K codewords include N mutually orthogonal codewords, and the mutual correlation between the K codewords is minimal.

23. The method according to any one of claims 14 to 22, characterized in that: The method further comprises: Sending first information, where the first information carries an index of a first precoder and / or an index of a first subsequence group; the first subsequence group corresponds to the first precoder, and the first precoder is used for signal precoding.

24. The method according to any one of claims 14 to 23, characterized in that: The number of subsequences included in the synchronization sequence is the same as the length of each subsequence included in the synchronization sequence.

25. The method according to claim 24, characterized in that The first subsequence included in the synchronization sequence is a multi-phase sequence; the general term of the first subsequence satisfies the following formula: Among them, a, b, c, d, p, q are constants; n=1, 2, ..., N, N represents the length of the first subsequence, and N is a positive integer; k=1, 2, ..., K, K represents the number of subsequences included in the synchronization sequence, and K is a positive integer.

26. The method according to claim 24 or 25, characterized in that Each subsequence included in the synchronization sequence occupies the same time domain resources, or each subsequence included in the synchronization sequence occupies the same frequency domain resources.

27. A communication device, characterized in that: The communication device comprises: a precoding module and a transceiver module; The precoding module is used to precode multiple subsequences included in the synchronization sequence according to the corresponding relationship between the precoder and the subsequence group; wherein: the first subsequence among the multiple subsequences is precoded using the precoder corresponding to the subsequence group where the first subsequence is located; The transceiver module is used to send a synchronization signal, where the synchronization signal includes the multiple precoded subsequences.

28. The communication device according to claim 27, characterized in that The total length of the subsequences contained in the subsequence group is an integer multiple of a first preset value.

29. The communication device according to claim 27, characterized in that The total length of the subsequences contained in the subsequence group is an integer multiple of a second preset value, wherein the total length of the subsequences contained in the subsequence group is obtained by padding extension.

30. The communication device according to any one of claims 27 to 29, characterized in that: The correspondence between the precoders and the subsequence groups includes: the precoders corresponding to every M subsequence groups constitute the same precoder set, and the precoder set includes M different precoders, M is a positive integer, 1<M<K, K represents the number of subsequence groups, and K is a positive integer.

31. The communication device according to claim 30, characterized in that: The precoders corresponding to each M subsequence groupings constitute the same precoder set, including: the precoders corresponding to each M subsequence groupings are the same.

32. The communication device according to any one of claims 27 to 29, characterized in that: The correspondence between the precoders and the subsequence groups includes: the precoders corresponding to each subsequence group are different from each other.

33. The communication device according to claim 32, characterized in that: The precoder corresponding to any subsequence group corresponds to one codeword among K codewords selected from the precoding matrix, where K represents the number of subsequence groups and is a positive integer.

34. The communication device according to claim 33, characterized in that K is less than or equal to N, where N represents the number of antennas and is a positive integer, and the K codewords are orthogonal to each other.

35. The communication device according to claim 33, characterized in that K is greater than N, where N represents the number of antennas and is a positive integer. The K codewords include N mutually orthogonal codewords, and the mutual correlation between the K codewords is minimal.

36. The communication device according to any one of claims 27 to 35, characterized in that: The transceiver module is further used to receive first information, where the first information carries an index of a first precoder and / or an index of a first subsequence group; the first subsequence group corresponds to the first precoder, and the first precoder is used for signal precoding.

37. The communication device according to any one of claims 27 to 36, characterized in that: The number of subsequences included in the synchronization sequence is the same as the length of each subsequence included in the synchronization sequence.

38. The communication device according to claim 37, characterized in that: The first subsequence included in the synchronization sequence is a multi-phase sequence; the general term of the first subsequence satisfies the following formula: Among them, a, b, c, d, p, q are constants; n=1, 2, ..., N, N represents the length of the first subsequence, and N is a positive integer; k=1, 2, ..., K, K represents the number of subsequences included in the synchronization sequence, and K is a positive integer.

39. The communication device according to claim 37 or 38, characterized in that: Each subsequence included in the synchronization sequence occupies the same time domain resources, or each subsequence included in the synchronization sequence occupies the same frequency domain resources.

40. A communication device, characterized in that: The communication device comprises: a transceiver module and a synchronization module; In the case where the communication device is a communication device of the first type, the transceiver module is used to receive a synchronization signal, where the synchronization signal includes a plurality of precoded subsequences; the synchronization module is used to perform downlink synchronization according to the synchronization signal; or In the case where the communication device is a communication device of the second type, the transceiver module is used to receive one or more precoded subsequences in the synchronization signal; the synchronization module is used to perform downlink synchronization according to one or more precoded subsequences in the synchronization signal; The encoded subsequence is obtained by precoding multiple subsequences included in the synchronization sequence according to the correspondence between the precoder and the subsequence grouping, and the bandwidth of the signal received by the first type of communication device is wider than the bandwidth of the signal received by the second type of communication device.

41. The communication device according to claim 40, characterized in that The total length of the subsequences contained in the subsequence group is an integer multiple of a first preset value.

42. The communication device according to claim 40, characterized in that The total length of the subsequences contained in the subsequence group is an integer multiple of a second preset value, wherein the total length of the subsequences contained in the subsequence group is obtained by padding extension.

43. The communication device according to any one of claims 40 to 42, characterized in that: The correspondence between the precoders and the subsequence groups includes: the precoders corresponding to every M subsequence groups constitute the same precoder set, and the precoder set includes M different precoders, M is a positive integer, 1<M<K, K represents the number of subsequence groups, and K is a positive integer.

44. The communication device according to claim 43, characterized in that The precoders corresponding to each M subsequence groupings constitute the same precoder set, including: the precoders corresponding to each M subsequence groupings are the same.

45. The communication device according to any one of claims 40 to 42, characterized in that: The correspondence between the precoders and the subsequence groups includes: the precoders corresponding to each subsequence group are different from each other.

46. ​​The communication device according to claim 45, characterized in that The precoder corresponding to any subsequence group corresponds to one codeword among K codewords selected from the precoding matrix, where K represents the number of subsequence groups and is a positive integer.

47. The communication device according to claim 46, characterized in that K is less than or equal to N, where N represents the number of antennas and is a positive integer, and the K codewords are orthogonal to each other.

48. The communication device according to claim 46, characterized in that K is greater than N, where N represents the number of antennas and is a positive integer. The K codewords include N mutually orthogonal codewords, and the mutual correlation between the K codewords is minimal.

49. The communication device according to any one of claims 40 to 48, characterized in that: The transceiver module is further used to send first information, where the first information carries an index of a first precoder and / or an index of a first subsequence group; the first subsequence group corresponds to the first precoder, and the first precoder is used for signal precoding.

50. The communication device according to any one of claims 40 to 49, characterized in that: The number of subsequences included in the synchronization sequence is the same as the length of each subsequence included in the synchronization sequence.

51. The communication device according to claim 50, characterized in that The first subsequence included in the synchronization sequence is a multi-phase sequence; the general term of the first subsequence satisfies the following formula: Among them, a, b, c, d, p, q are constants; n=1, 2, ..., N, N represents the length of the first subsequence, and N is a positive integer; k=1, 2, ..., K, K represents the number of subsequences included in the synchronization sequence, and K is a positive integer.

52. The communication device according to claim 50 or 51, characterized in that: Each subsequence included in the synchronization sequence occupies the same time domain resources, or each subsequence included in the synchronization sequence occupies the same frequency domain resources.

53. A communication device, characterized in that: The communication device includes: a module or unit for implementing the method according to any one of claims 1 to 13; or a module or unit for implementing the method according to any one of claims 14 to 26.

54. A communication device, characterized in that: include: A memory and a processor coupled to the memory, the memory being used to store a program, and the processor being used to execute the program stored in the memory; when the communication device is running, the processor runs the program, so that the communication device executes the method described in any one of claims 1 to 13; or, the communication device executes the method described in any one of claims 14 to 26.

55. A communication system, characterized in that: The communication system includes a network device and a terminal device; wherein the network device is used to execute the method according to any one of claims 1-13, and the terminal device is used to execute the method according to any one of claims 14-26.

56. A computer-readable storage medium, characterized in that A computer program is stored thereon, which, when executed by a computer, enables the computer to execute the method described in any one of claims 1 to 13; or, when executed by a computer, enables the computer to execute the method described in any one of claims 14 to 26.

57. A computer program product, characterized in that The computer program product comprises computer instructions, and when the computer instructions are executed on a computer, the computer is caused to execute the method according to any one of claims 1 to 13, or the computer is caused to execute the method according to any one of claims 14 to 26.

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