Pilot transmission method and apparatus

Abstract

The present application discloses a pilot transmission method and apparatus. The method comprises: determining a first length; on the basis of the first length, determining a first sequence pair, wherein the first sequence pair comprises at least two sequences, and the length of each of the at least two sequences is the first length; on the basis of the first sequence pair, generating at least two pilot symbols; and outputting the at least two pilot symbols. According to the solution, when pilot symbols are generated, the length of the sequences used to generate the pilot symbols is taken into consideration, so that the pilot symbols can be generated on the basis of sequences having an appropriate length (i.e., the first length), thereby achieving the technical effect of balancing the overhead and effectiveness of channel estimation.

Description

A pilot transmission method and device

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to the Chinese patent application filed with the State Intellectual Property Office of China on November 3, 2023, with application number 202311458689.8 and application name “A pilot transmission method and device”, the entire contents of which are incorporated by reference into this application. Technical Field

[0003] The present application relates to the field of communication technology, and in particular to a pilot transmission method and device. Background Art

[0004] Pilot signals generated based on the Gold sequence have a low peak-to-average power ratio (PAPR), but their frequency domain flatness is poor. This means that some subcarriers may have low signal energy. When the receiver performs channel estimation, the signal-to-noise ratio (SNR) of these subcarriers is very low, resulting in poor channel estimation quality. Pilot signals generated based on the Zadoff-Chu (ZC) sequence have good frequency domain flatness, but their PAPR is high. This means that the pilot signal may be distorted after amplification by the power amplifier, making it difficult for the receiver to correctly interpret the pilot signal.

[0005] Pilot signals generated using Golay complementary sequence pairs can achieve both low PAPR and frequency domain flatness. However, the length of Golay complementary sequences (GCS) is limited. If the sequence length is too long, the generated pilot signals occupy a large number of channels that do not need to be estimated, increasing the channel estimation overhead. If the sequence length is too short, it cannot effectively estimate all the channels that need to be estimated, resulting in inaccurate channel estimation.

[0006] Therefore, how to select a Golay complementary sequence pair of appropriate length to generate a pilot signal while taking into account the overhead and effectiveness of channel estimation is a technical problem that needs to be solved urgently.

[0007] Summary of the Invention

[0008] The present application provides a pilot transmission method and apparatus, which can generate a pilot signal based on a sequence of appropriate length, thereby achieving the technical effect of balancing the overhead and effectiveness of channel estimation.

[0009] In a first aspect, a pilot transmission method is provided. The method can be performed by a first communication device. Unless otherwise specified, the "first communication device" in this application can refer to the first communication device itself (e.g., a network device, a terminal device), a component in the first communication device (e.g., a processor, a chip, or a chip system), or a logic module or software that can implement all or part of the functions of the first communication device. The method includes: determining a first length; determining a first sequence pair based on the first length; wherein the first sequence pair includes at least two sequences, each of the at least two sequences having a length of the first length; generating at least two pilot symbols based on the first sequence pair; and outputting the at least two pilot symbols.

[0010] When generating pilot symbols, the above scheme takes into account the length of the sequence used to generate pilot symbols, and can generate pilot symbols based on a sequence of appropriate length (i.e., the first length), so that the bandwidth occupied by the finally generated pilot symbol matches (e.g., is consistent with) the bandwidth of the channel to be estimated (e.g., the transmission bandwidth of the first data symbol), thereby ensuring that the receiving end of the pilot symbol can effectively estimate all channels that need to be estimated without increasing additional channel estimation overhead, that is, taking into account both the overhead and effectiveness of channel estimation.

[0011] In one possible design, the first sequence pair is a Golay complementary sequence pair.

[0012] In one possible design, the Golay complementary sequence is a binary Golay complementary sequence.

[0013] Compared with the quaternary Golay complementary sequence or the multi-element Golay complementary sequence, the binary Golay complementary sequence can lower the PAPR of the pilot signal.

[0014] In one possible design, first information can be received from a network device, where the first information indicates a first length; and the first length is determined based on the first information.

[0015] In this way, the complexity of determining the first length can be reduced.

[0016] In one possible design, the first information includes a factor set, and the factor set includes at least one of the first factor, the second factor, and / or the third factor. Accordingly, determining the first length based on the first information may include: determining the first length based on the factor set.

[0017] By adopting this method, the data volume of the first information can be reduced, thereby saving resource overhead.

[0018] In one possible design, the first factor, the second factor, the third factor, and the first length satisfy the following relationship: N = 2 a 10 b 26c ;

[0019] Wherein, N is the first length, a is the first factor, b is the second factor, c is the third factor, and a, b, and c are natural numbers.

[0020] Of course, the above relationship is only an example and is not limited to this. For example, N=2 a 10 b etc., which can take into account the bandwidth scheduling level of the 5G system.

[0021] In one possible design, the first length is related to the transmission bandwidth of the first data symbol, and the first data symbol and at least two pilot symbols are mapped to the same frequency domain resources. In other words, the first length can be determined based on the transmission bandwidth of the first data symbol.

[0022] In one possible design, the length corresponding to the transmission bandwidth and first parameter of the first data symbol can be determined based on the correspondence between the transmission bandwidth, parameters, and length of the data symbol, and the determined length is the first length; wherein the parameters include a roll-off factor and / or bandwidth extension, and the first parameter includes the roll-off factor and / or bandwidth extension factor used to generate the first data symbol.

[0023] By adopting this method, the network device does not need to indicate the first length, resource overhead can be reduced, and the implementation is simple.

[0024] In one possible design, the first length can be determined based on the transmission bandwidth of the first data symbol and a first parameter, where the first parameter includes a roll-off factor and / or a bandwidth expansion factor used to generate the first data symbol.

[0025] By adopting this method, the network device does not need to indicate the first length, which can reduce resource overhead.

[0026] In one possible design, determining the first length based on the transmission bandwidth of the first data symbol and the first parameter may include: determining the first length based on the transmission bandwidth of the first data symbol, the roll-off factor used to generate the first data symbol, the first coefficient afa, and the second coefficient; or determining the first length based on the transmission bandwidth of the first data symbol, the bandwidth expansion factor used to generate the first data symbol, the first coefficient afa, and the second coefficient. Wherein, the second coefficient is 2 a 10 b 26 c , a, b, c are natural numbers.

[0027] In one possible design, the first length is N and the transmission bandwidth of the first data symbol is M.

[0028] N is equal to 2 a 10 b 26c , where N is the largest integer less than or equal to M, and a, b, and c are natural numbers; or,

[0029] N is equal to 2 a 10 b , where N is the largest integer less than or equal to M, and a and b are natural numbers; or,

[0030] N is equal to 2 a , and N is the largest integer less than or equal to M, and a is a natural number.

[0031] In this way, it can be ensured that the first length meets the length requirement of the Golay complementary sequence pair while being as close to the transmission bandwidth as possible.

[0032] In one possible design, if N is less than M, each sequence in the first sequence pair is extended to a length equal to the transmission bandwidth to obtain an extended first sequence pair; and at least two pilot symbols are generated based on the extended first sequence pair.

[0033] For example, a discrete Fourier transformation (DFT) is performed on any sequence in the first sequence pair; and a cyclic extension is performed on any sequence after the DFT, so as to extend the length of any sequence after the DFT from N to M.

[0034] For example, before performing a DFT on any sequence in the first sequence pair, zeros are padded to any sequence, with the number of padded zeros being MN, to extend the length of any sequence from N to M. Padding any sequence with zeros includes one or more of the following: padding the beginning of any sequence with zeros; padding the end of any sequence with zeros; or padding zeros evenly between elements in any sequence. The above padding methods are merely examples and are not intended to be limiting.

[0035] With this design, each sequence in the first sequence pair can be extended to the same length as the transmission bandwidth, thereby ensuring that the finally generated pilot symbol can be used to effectively estimate all channels where the first data symbol is located.

[0036] In one possible design, the first length is N, and the transmission bandwidth of the first data symbol is M;

[0037] N is equal to 2 a 10 b 26 c , where N is the smallest integer greater than or equal to M, and a, b, and c are natural numbers; or,

[0038] N is equal to 2 a 10 b, where N is the smallest integer greater than or equal to M, and a and b are natural numbers; or,

[0039] N is equal to 2 a , and N is the smallest integer greater than or equal to M, and a is a natural number.

[0040] In this way, it can be ensured that the first length meets the length requirement of the Golay complementary sequence pair while being as close to the transmission bandwidth as possible.

[0041] In one possible design, if N is greater than M, each sequence in the first sequence pair is truncated to obtain a truncated first sequence pair; and at least two pilot symbols are generated based on the truncated first sequence pair.

[0042] With this design, each sequence in the first sequence pair can be truncated to the same length as the transmission bandwidth, thereby ensuring that the finally generated pilot symbol can be used to effectively estimate all channels where the first data symbol is located.

[0043] In one possible design, the filter used to generate each pilot symbol in the at least two pilot symbols is the same, and / or the bandwidth extension factor used to generate each pilot symbol in the at least two pilot symbols is the same.

[0044] In this way, pilot symbols with complementary properties can use the same spectrum expansion, and then can be generated or processed based on the same filter, providing support conditions for the receiving end to jointly process pilot symbols with complementary properties.

[0045] In one possible design, at least two pilot symbols are located within a time domain window (TDW); the filters used to generate the multiple pilot symbols within the TDW are the same, and / or the bandwidth extension factors used to generate the multiple pilot symbols within the TDW are the same.

[0046] In this way, the pilot symbols in the TDW can be generated or processed based on the same filter, providing support conditions for the receiving end to perform joint processing on the pilot symbols in the TDW.

[0047] In one possible design, the filter used to generate the pilot symbol is the same as the filter used to generate the first data symbol; and / or the bandwidth expansion factor used to generate the pilot symbol is the same as the bandwidth expansion factor used to generate the first data symbol.

[0048] In this way, pilot symbols and data symbols can be generated or processed based on the same filter without distinguishing between pilot symbols and data symbols, thereby enabling transparent transmission and reducing the complexity of signal processing.

[0049] In a second aspect, a pilot transmission method is provided, which can be performed by a second communication device. Unless otherwise specified, the "second communication device" in this application can refer to the second communication device itself (for example, a terminal device, a network device), or a component in the second communication device (for example, a processor, a chip, or a chip system, etc.), or a logic module or software that can implement all or part of the functions of the second communication device. The method includes: obtaining a signal to be decoded; wherein the signal to be decoded includes at least two pilot symbols, the at least two pilot symbols are generated based on a first sequence pair, the first sequence pair includes at least two sequences, and the length of each sequence in the at least two sequences is a first length; and performing channel estimation on the at least two pilot symbols.

[0050] In the above scheme, the pilot symbols received by the second communication device are generated based on the first sequence pair, so all channels where the data symbols are located can be effectively estimated without adding additional channel estimation overhead, thus taking into account both the overhead and effectiveness of channel estimation.

[0051] In one possible design, performing joint channel estimation on at least two pilot symbols may include performing joint channel estimation on at least two pilot symbols or performing joint processing on at least two pilot symbols.

[0052] In one possible design, the first sequence pair is a Golay complementary sequence pair.

[0053] In one possible design, the first sequence pair is a binary Golay complementary sequence pair.

[0054] In one possible design, the second communication device is a network device, and the second communication device can also send first information, where the first information indicates a first length.

[0055] In this way, the receiving end of the first information (such as the first communication device) can directly determine the first length based on the first information, thereby reducing the complexity of the first communication device in determining the first length.

[0056] In one possible design, the first information includes a factor set, and the factor set includes at least one of the first factor, the second factor, and / or the third factor.

[0057] In one possible design, the first factor, the second factor, the third factor, and the first length satisfy the following relationship: N = 2 a 10 b 26 c ;

[0058] Wherein, N is the first length, a is the first factor, b is the second factor, c is the third factor, and a, b, and c are natural numbers.

[0059] In one possible design, the first length is related to the transmission bandwidth of the first data symbol, and the first data symbol and at least two pilot symbols are mapped to the same frequency domain resources.

[0060] In one possible design, the length corresponding to the transmission bandwidth and first parameter of the first data symbol can be determined based on the correspondence between the transmission bandwidth, parameters, and length of the data symbol, and the determined length is the first length; wherein the parameters include a roll-off factor and / or bandwidth extension, and the first parameter includes the roll-off factor and / or bandwidth extension factor used to generate the first data symbol.

[0061] In one possible design, the first length can be determined based on the transmission bandwidth of the first data symbol and a first parameter, where the first parameter includes a roll-off factor and / or a bandwidth expansion factor used to generate the first data symbol.

[0062] In one possible design, determining the first length based on the transmission bandwidth of the first data symbol and the first parameter may include:

[0063] The first length is determined according to the transmission bandwidth of the first data symbol, the roll-off factor used to generate the first data symbol, the first coefficient afa, and the second coefficient; wherein the second coefficient is 2 a 10 b 26 c , a, b, c are natural numbers; or,

[0064] The first length is determined according to the transmission bandwidth of the first data symbol, the bandwidth expansion factor used to generate the first data symbol, the first coefficient afa, and the second coefficient; wherein the second coefficient is 2 a 10 b 26 c , a, b, c are natural numbers.

[0065] In one possible design, the first length is N, and the transmission bandwidth of the first data symbol is M;

[0066] N is equal to 2 a 10 b 26 c , where N is the largest integer less than or equal to M, and a, b, and c are natural numbers; or,

[0067] N is equal to 2 a 10 b , where N is the largest integer less than or equal to M, and a and b are natural numbers; or,

[0068] N is equal to 2 a , and N is the largest integer less than or equal to M, and a is a natural number.

[0069] In one possible design, the first length is N, and the transmission bandwidth of the first data symbol is M;

[0070] N is equal to 2 a 10 b 26 c , where N is the smallest integer greater than or equal to M, and a, b, and c are natural numbers; or,

[0071] N is equal to 2 a 10 b , where N is the smallest integer greater than or equal to M, and a and b are natural numbers; or,

[0072] N is equal to 2 a , and N is the smallest integer greater than or equal to M, and a is a natural number.

[0073] The beneficial effects of the above-mentioned design methods can refer to the beneficial effects of the corresponding designs in the first aspect, and will not be repeated here.

[0074] According to a third aspect, a communication device is provided, which includes a module, a unit, or a technical means for implementing the method described in the first aspect or any possible design of the first aspect.

[0075] Exemplarily, the apparatus may include:

[0076] a processing module, configured to determine a first length; determine a first sequence pair based on the first length; wherein the first sequence pair includes at least two sequences, and the length of each sequence in the at least two sequences is the first length; and generate at least two pilot symbols based on the first sequence pair;

[0077] The transceiver module is configured to output at least two pilot symbols.

[0078] In a fourth aspect, a communication device is provided, which includes a module, unit or technical means for implementing the method described in the second aspect or any possible design of the second aspect.

[0079] Exemplarily, the apparatus may include:

[0080] a transceiver module, configured to obtain a signal to be decoded; wherein the signal to be decoded includes at least two pilot symbols, the at least two pilot symbols are generated based on a first sequence pair, the first sequence pair includes at least two sequences, and the length of each sequence in the at least two sequences is the first length;

[0081] The processing module is configured to perform channel estimation on at least two pilot symbols.

[0082] In a fifth aspect, a communication device is provided, which includes a processor and an interface circuit, wherein the interface circuit is electrically coupled to the processor, and the processor causes the method described in the first aspect or any possible design of the first aspect to be executed through a logic circuit or execution code instructions, or causes the method described in the second aspect or any possible design of the second aspect to be executed.

[0083] In a sixth aspect, a computer-readable storage medium is provided, wherein a computer program or instruction is stored in the storage medium. When the computer program or instruction is executed, the method described in the first aspect or any possible design of the first aspect is executed, or the method described in the second aspect or any possible design of the second aspect is executed.

[0084] In the seventh aspect, a computer program product is provided, comprising instructions, which, when run on a computer, causes the method described in the first aspect or any possible design of the first aspect to be executed, or causes the method described in the second aspect or any possible design of the second aspect to be executed.

[0085] The specific designs and beneficial effects of the third to seventh aspects mentioned above can refer to the corresponding designs and beneficial effects in the first to second aspects. BRIEF DESCRIPTION OF THE DRAWINGS

[0086] FIG1 is a flowchart of processing a DFT-s-OFDM signal;

[0087] FIG2 is a schematic diagram of a communication system applicable to an embodiment of the present application;

[0088] FIG3 is a flowchart of a pilot transmission method provided in an embodiment of the present application;

[0089] FIG4 is an example diagram of frequency domain cyclic extension;

[0090] FIG5 is a flowchart of another pilot transmission method provided in an embodiment of the present application;

[0091] FIG6 is a schematic diagram of (joint) channel estimation;

[0092] FIG7 is a schematic structural diagram of a communication device provided in an embodiment of the present application;

[0093] FIG8 is a schematic structural diagram of another communication device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0094] To facilitate understanding of the technical solutions provided in the embodiments of the present application, some of the technical terms mentioned in the embodiments of the present application are explained and illustrated below.

[0095] (1) Single carrier and multi-carrier:

[0096] Single-carrier refers to convolving a roll-off filter with serially arranged transmission signals to form a transmission signal; multi-carrier refers to arranging transmission signals in parallel and forming a transmission signal through inverse fast Fourier transform (IFFT).

[0097] For example, the single-carrier waveform may be a single carrier-quadrature amplitude modulation (SC-QAM) waveform, and the multi-carrier waveform may be an orthogonal frequency division multiplexing (OFDM) waveform. Furthermore, the discrete Fourier transform-spread-orthogonal frequency division multiplexing (DFT-s-OFDM) waveform is almost equivalent to the traditional single-carrier waveform, but uses a multi-carrier implementation, making it easily compatible with OFDM. However, it is still essentially a single-carrier waveform.

[0098] FIG1 is a flow chart of signal processing of a transmitter of a network device or a terminal device when a DFT-s-OFDM waveform is used for communication between the network device and the terminal device.

[0099] As shown in Figure 1, the transmitter modulates the coded bit stream to obtain a modulated data sequence. The transmitter performs time domain resource mapping on the reference signal sequence and the modulated sequence (i.e., determines the time domain resources for each sequence, such as determining the OFDM symbol carrying each sequence). The reference signal sequence is, for example, at least one of a demodulation reference signal (DMRS) sequence, a phase tracking reference signal (PTRS) sequence, a tracking reference signal (TRS) sequence, or a channel state information-reference signal (CSI-RS) sequence. The transmitter performs transform domain coding on the sequence after time domain resource mapping (such as a discrete Fourier transformation (DFT) operation to transform it into the frequency domain); performs subcarrier mapping on the sequence after DFT (such as mapping it to a resource element (RE)); performs IFFT on the sequence after subcarrier mapping and superimposes a cyclic prefix (CP) to obtain a DFT-s-OFDM sequence.

[0100] The receiver performs the opposite process to the transmitter. For example, after obtaining the DFT-s-OFDM sequence, the receiver removes the superimposed CP in the sequence and performs operations such as DFT, subcarrier demapping, and IDFT to recover the reference signal sequence and the coded bit stream.

[0101] It is understandable that the relevant operations in Figure 1 are only an example. Optionally, other possible operations may also be included, such as frequency domain spectrum shaping, serial-to-parallel conversion, parallel-to-serial conversion, digital-to-analog-converter (DAC), power amplifier (PA), low noise amplifier (LNA), analog-to-digital converter (ADC), etc.

[0102] (2) PAPR:

[0103] Observed in the time domain, wireless signals are sinusoidal waves with varying amplitudes. The amplitude is not constant. The peak amplitude of a signal within one cycle is different from the peak amplitude of another cycle, so the average power and peak power in each cycle are different. Over a long period of time, peak power is the maximum instantaneous power with a certain probability of occurring, typically 0.01% (10^-4). The ratio of the peak power at this probability to the total average power of the system is the PAPR.

[0104] (3) Gray complementary sequence pair:

[0105] For two sequences of length n, a=(a0, a1, a2, ..., a n-1 ) and b=(b0,b1,b2,…,b n-1 ),set up:

[0106] If sequence a and sequence b meet the following requirements, then sequence a and sequence b form a Golay complementary sequence pair (or a pair of Golay complementary sequences), a is a Golay complementary sequence, and b is a Golay complementary sequence:

[0107] For any 0<j<n-1, G a (j)+G b (j) = 0, and when j = 0, G a (j)+G b (j) = 2n.

[0108] In other words, in a Gray complementary sequence pair, the sum of the autocorrelations of the two sequences is 0 when j is not 0, and is 2n when j is 0.

[0109] It is understood that for sequence a, in addition to sequence b, there may be other sequences that meet the above requirements as well as sequence a. For sequence b, in addition to sequence a, there may be other sequences that meet the above requirements as well as sequence b. Therefore, the number of Golay complementary sequences in a Golay complementary sequence pair can be two or more.

[0110] According to the types of elements contained in the Golay complementary sequence, the Golay complementary sequence can be divided into a binary Golay complementary sequence, a quaternary Golay complementary sequence, and a multi-element Golay complementary sequence.

[0111] (4) Roll-off factor: Also known as roll-off parameter, roll-off coefficient, etc. The roll-off factor is used to describe the slope of the filter edge. When transmitting a signal, a spectrum expansion roll-off filter can be used to expand the bandwidth occupied by the symbol to achieve spectrum expansion. After expansion, the bandwidth occupied by the symbol is 1 + α times the original bandwidth, so α is the roll-off factor. For example, if the original bandwidth is 10 MHz, after frequency domain spectral shaping (FDSS) with α = 0.2, the occupied bandwidth is 12 MHz.

[0112] (5) Bandwidth expansion factor: Also known as the expansion factor, bandwidth expansion coefficient, or extended bandwidth, it refers to the ratio of the bandwidth after extension (PRBs after extension) to the original bandwidth (PRBs before extension). The extended bandwidth includes both the original bandwidth and the extended portion. For example, if the original bandwidth is 100 REs and the spectrum spread roll-off filter is used to expand the bandwidth by 100 REs, the bandwidth after extension is 200 REs, and the bandwidth expansion factor is (100 + 100) / 100 = 200%.

[0113] When the filter used by the system matches the extended bandwidth, the roll-off factor and the bandwidth expansion factor have the following corresponding relationship: β = 1 + α. That is, when the system uses a filter with a roll-off factor of α, the corresponding extended bandwidth is β = 1 + α. However, in reality, the filter and the extended bandwidth do not necessarily match exactly, so other corresponding relationships are possible, such as β = 0.9 + α or β = 1.1 + α. That is, when the system uses a filter with a roll-off factor of α, the corresponding extended bandwidth is 0.9 + α or β = 1.1 + α.

[0114] (6) The term "multiple" in the embodiments of the present application refers to two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B may represent three situations: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship. In addition, it should be understood that although the terms "first", "second", etc. may be used to describe each object in the embodiments of the present invention, these objects should not be limited to these terms. These terms are only used to distinguish each object from each other.

[0115] The terms "including" and "having" and any variations thereof mentioned in the description of the embodiments of the present application are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but may optionally include other steps or units that are not listed, or may optionally include other steps or units that are inherent to these processes, methods, products or devices. It should be noted that in the embodiments of the present application, words such as "exemplary" or "for example" are used to indicate examples, illustrations or descriptions. 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.

[0116] Below, the technical solutions provided in the embodiments of the present application are explained and illustrated with reference to the accompanying drawings.

[0117] The technical solutions in the embodiments of the present application can be applied to various communication systems, such as fifth-generation (5G) mobile communication systems, such as new radio (NR) systems, sixth-generation (6G) mobile communication systems, universal mobile telecommunications systems (UMTS), wireless local area networks (WLAN), wireless fidelity (Wi-Fi) systems, and other communication systems that will evolve in the future.

[0118] The embodiments of the present application can be applied to the following scenarios: enhanced mobile broadband (eMBB), multi-site transmission (the same terminal device transmits signals to multiple sites), backhaul scenarios, wireless broadband to the home (WTTx), device to device (D2D), or other scenarios with high timing requirements or high transmission rate requirements.

[0119] For example, Figure 2 is a schematic diagram of a communication system applicable to an embodiment of the present application. As shown in Figure 2, the communication system may include one or more network devices and one or more terminal devices. The interface between the network device and the terminal device may be a Uu interface (or air interface), and data may be transmitted between the network device and the terminal device via air interface resources.

[0120] FIG2 exemplifies scenarios applicable to embodiments of the present application, namely, eMBB (shown by the solid line in FIG2 ), multi-site transmission (shown by the dashed line ① in FIG2 ), backhaul scenario (shown by the dashed line ② in FIG2 ), and D2D (shown by the dashed line ③ in FIG2 ). It should be understood that the four scenarios shown in FIG2 are merely examples and are not limited to these by embodiments of the present application.

[0121] The network device 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 base station in a sixth generation (6G) mobile communication system, a base station in a future mobile communication system, or an access node in a wireless fidelity (WiFi) system, etc.; it can also be a module or unit that performs some of the functions of a base station, for example, a centralized unit (CU) or a distributed unit (DU). The access network device can be a macro base station (such as 110a in Figure 2), a micro base station or an indoor station (such as 110b in Figure 2), a relay node or a donor node, etc. The embodiments of the present application do not limit the specific technology and specific device form adopted by the access network device. In the embodiments of the present application, a base station is used as an example of an access network device for description.

[0122] In one possible scenario, multiple RAN nodes collaborate to assist the terminal in achieving wireless access, and different RAN nodes respectively implement part of the functions of the base station. For example, the 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 separately, or they can be included in the same network element, such as a baseband unit (BBU). The RU can be included in a radio frequency device or radio frequency unit, such as a remote radio unit (RRU), an active antenna unit (AAU), or a remote radio head (RRH).

[0123] 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 radio access network (O-RAN or open RAN or 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 takes 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 can be implemented by a software module, a hardware module, or a combination of a software module and a hardware module.

[0124] Terminal devices may also be referred to as terminals, user equipment (UE), mobile stations, mobile terminals, etc. Terminal devices can be widely used in various scenarios, for example, 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. Terminal devices may be mobile phones, tablet computers, computers with wireless transceiver functions, wearable devices, vehicles, drones, helicopters, airplanes, ships, robots, robotic arms, smart home devices, etc. The embodiments of the present application do not limit the specific technology and specific device form adopted by the terminal devices.

[0125] Base stations and UEs can be fixed or mobile. They can be deployed on land, indoors or outdoors, handheld or vehicle-mounted; on water; or in the air on aircraft, balloons, and satellites. The embodiments of this application do not limit the application scenarios of base stations and UEs.

[0126] Communication between base stations and UEs, between base stations, and between UEs 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.

[0127] The communication system and scenarios described in the embodiments of the present application are intended to more clearly illustrate the technical solutions of the embodiments of the present application, and do not constitute a limitation on the technical solutions provided in the embodiments of the present application. A person skilled in the art will appreciate that, with the evolution of network architecture and the emergence of new scenarios, the technical solutions provided in the embodiments of the present application are equally applicable to similar technical problems.

[0128] In the embodiment of the present application, the waveform used for communication between the network device and the terminal device can be a single-carrier waveform or a multi-carrier waveform. In the embodiment of the present application, a DFT-s-OFDM waveform is used as an example for description.

[0129] Referring to Figure 3, a pilot transmission method is provided in an embodiment of the present application, which can be applied to the communication system shown in Figure 2. The method can be executed by a first communication device. Unless otherwise specified, the "first communication device" in this application can refer to the first communication device itself (for example, the network device or terminal device shown in Figure 2), or a component in the first communication device (for example, a processor, a chip, or a chip system, etc.), or a logic module or software that can implement all or part of the functions of the first communication device. The method includes:

[0130] S301, determining a first length;

[0131] There are many ways to determine the first length, including but not limited to the following:

[0132] Method 1: Receive first information from a network device, where the first information indicates a first length; and determine the first length according to the first information.

[0133] It can be understood that when the first communication device is a terminal device, the first communication device can receive the first information from the network device; when the first communication device is a network device, the first communication device can receive the first information from another network device.

[0134] In a possible implementation, the first information may directly indicate the first length, that is, the first information is the value of the first length, such as 512.

[0135] By adopting the above implementation manner, the complexity of determining the first length can be reduced.

[0136] In another possible implementation, the first information indirectly indicates the first length. For example, the first information includes a factor set, the factor set includes at least one of the first factor, the second factor, and / or the third factor; and the first communication device determines the first length based on the factor set.

[0137] For ease of description, this document uses N to represent the first length, a to represent the first factor, b to represent the second factor, and c to represent the third factor. The values ​​of a, b, and c are all natural numbers.

[0138] In some embodiments, the factor set includes a, b, c, and a, b, c and N satisfy the following relationship: N=2 a 10 b 26 c After receiving the first information, the first communication device can determine the first length according to a, b, and c, that is, 2 a 10 b 26 c .

[0139] In some embodiments, one or more factors among a, b, and c may be fixed values. In this case, the first information may only include the parts of a, b, and c other than the fixed values.

[0140] For example, if c is fixed to 0, the first information may only include a and b.

[0141] For example, if a is fixed to 1, the first information may only include c and b.

[0142] In some embodiments, when the value of any factor among a, b, and c is 0, the first information may not include the factor, or the factor does not exist.

[0143] For example, the factor set includes a, b, a, b and N satisfy the following relationship: N = 2 a 10 b Considering that in 5G communication systems, the bandwidth scheduling level is the resource block (RB) level, that is, 12 subcarriers form one RB, so the scheduling bandwidth is an integer multiple of 12. Therefore, c can be set to 0, or there are only two factors, a and b.

[0144] For example, the factor set includes a, a and N satisfy the following relationship: N = 2 a .

[0145] Of course, the above is only an example, and the actual implementation of the factor set is not limited to this.

[0146] By adopting the above implementation method, the data volume of the first information can be reduced, thereby saving resource overhead.

[0147] Mode 2: The first length is related to a transmission bandwidth of the first data symbol, wherein the first data symbol and at least two pilot symbols are mapped to the same frequency domain resource.

[0148] In some embodiments, the transmission bandwidth of the first data symbol may refer to the bandwidth before extension (PRBs before extension) or the bandwidth after extension (PRBs after extension), without limitation. For ease of description, the transmission bandwidth before extension is used as an example below.

[0149] For the convenience of description, M is used herein to represent the transmission bandwidth of the first data symbol.

[0150] It will be appreciated that in this embodiment of the present application, the first length is used to determine (or generate) the length of the first sequence pair (see S302). That is, the length of each sequence in the first sequence pair is the first length. The first sequence pair is used to generate pilot symbols (see S303), which are used for channel estimation. Therefore, when determining the first length, the bandwidth of the channel to be estimated (i.e., the transmission bandwidth of the first data symbol) can be referenced.

[0151] In a specific implementation, the transmission bandwidth of the first data symbol can be the frequency bandwidth occupied by the first data symbol (for example, 20 MHz), or the number of RBs occupied by the first data symbol (such as 100 RBs), or the number of subcarriers occupied by the first data symbol (for example, 1200 subcarriers), or the number of resource elements (RE) occupied by the first data symbol (for example, 1200 REs), and so on.

[0152] Method 2 can be implemented in many ways. The following are two possible examples:

[0153] 1) Determine a first length based on a correspondence between a transmission bandwidth, a parameter, and a length of a data symbol, wherein the parameter includes a roll-off factor and / or a bandwidth extension.

[0154] Specifically, based on the correspondence between the transmission bandwidth, parameters, and length of the data symbol, a length corresponding to the transmission bandwidth of the first data symbol and the first parameter is determined. The determined length is the first length. The first parameter includes a roll-off factor and / or a bandwidth expansion factor used to generate the first data symbol. For the roll-off factor and bandwidth expansion factor, please refer to the relevant definitions in the technical terminology section above and will not be repeated here.

[0155] Table 1 provides a specific example of the corresponding relationship. A row in Table 1 is a set of transmission bandwidths, roll-off factors, and lengths that correspond to each other.

[0156] Table 1

[0157] Of course, in practical applications, the corresponding relationship is not limited to the example given in Table 1.

[0158] For example, when the transmission bandwidth is 960 REs and the roll-off factor is 0.2, the length is not limited to 512; when the transmission bandwidth is 960 REs and the roll-off factor is 1, the length is not limited to 640.

[0159] For example, the corresponding relationship may include only some of the roll-off factors and lengths shown in Table 1; or, the corresponding relationship may also include other roll-off factors or lengths, such as 520, 676, 800, and 832 shown in Table 2. It is understood that the values ​​of the roll-off factors are not shown in Table 2.

[0160] Table 2

[0161] For example, the table may be in a form where each column is a set of transmission bandwidth, roll-off factor, and length that correspond to each other.

[0162] For example, the representation of the corresponding relationship is not limited to a table, and may also be an array, a text description, etc.

[0163] In a specific implementation, the above correspondence relationship may be specified by a protocol, or pre-configured in the first communication device, or notified to the first communication device by other devices (such as network devices), etc., and this application does not impose any restrictions.

[0164] Through the above implementation method, the first terminal device can quickly determine the first length based on the corresponding relationship, which can reduce the complexity of determining the first length while reducing transmission overhead.

[0165] 2) Determine the first length according to the transmission bandwidth of the first data symbol and a first parameter, wherein the first parameter includes a roll-off factor and / or a bandwidth extension factor used to generate the first data symbol.

[0166] In one possible implementation, the first length is: under the transmission bandwidth of the first data symbol and the constraints of the first parameter, the PAPR of the pilot symbol is less than the PAPR of the first data symbol, and the PAPR of the pilot symbol can reach the optimal (such as the lowest) length.

[0167] For example, the transmission bandwidth of the first data symbol is 100 RBs = 1200 REs, and the bandwidth expansion factor is 100% (or the roll-off factor is 0). The first data symbol is transmitted based on the Pi / 2-BPSK method. Then, in order to prevent the pilot symbol's PAPR from being higher than the first data symbol's PAPR, resulting in the pilot symbol's nonlinearity being greater than the data symbol and causing channel estimation loss, the pilot symbol's PAPR needs to be lower than the first data symbol's PAPR. Since the bandwidth expansion factor of the first data symbol is 100% (i.e., the first data symbol actually occupies 100 RBs), the pilot symbol's bandwidth expansion factor should be greater than or equal to 100% and less than or equal to 170% to ensure that the pilot symbol's PAPR is no higher than the first data symbol's PAPR. When the pilot symbol's bandwidth expansion factor is 150%, the pilot symbol's PAPR can be optimized (e.g., lowest). 170% and 150% are empirical parameters, and other possible values ​​exist.

[0168] In a specific implementation, the first coefficient afa can be determined based on the transmission bandwidth, roll-off factor and / or bandwidth expansion factor corresponding to the first data symbol, and then the optimal solution for the first length (i.e., the length of the pilot symbol that can achieve the lowest PAPR) can be solved based on the first coefficient afa.

[0169] The first coefficient afa is a coefficient used to optimize the PAPR (which may be referred to as a PAPR optimization coefficient). The first coefficient afa corresponds to the roll-off factor and / or bandwidth extension factor corresponding to the pilot symbol when the PAPR of the pilot symbol is optimal. This means that under the constraints of the transmission bandwidth of the first data symbol and the roll-off factor and / or bandwidth extension factor used to generate the first data symbol, the first length calculated based on the first coefficient can achieve the optimal PAPR for the pilot symbol.

[0170] Optionally, afa may be a proportional coefficient that may represent the ratio of the total bandwidth length of the pilot symbol after bandwidth expansion to the first length. In a specific implementation, the value of afa may be determined through data simulation. For example, when the bandwidth expansion factor is 100%, afa may be 1 / 2.

[0171] Exemplarily, the first length is determined based on the transmission bandwidth of the first data symbol, the first parameter, the first coefficient afa, and the second coefficient. The second coefficient is 2a10b26c. For example:

[0172] Determine the first length according to the transmission bandwidth of the first data symbol, the roll-off factor used to generate the first data symbol, the first coefficient afa, and the second coefficient; or,

[0173] The first length is determined according to the transmission bandwidth of the first data symbol, the bandwidth extension factor used to generate the first data symbol, the first coefficient afa, and the second coefficient.

[0174] In specific implementation, the first length can be calculated using the formula, for example: Length_GCS=min (a,b,c) (abs(Data_Num*Extend_BW*afa-2 a 10 b 26 c )); or, Length_GCS=min (a,b,c) (abs(Data_Num*(1+Roll_off)*afa-2 a 10 b 26 c )).

[0175] Wherein, abs represents the absolute value function (absolute value); Data_Num represents the transmission bandwidth of the first data symbol (for example, M in the above text); Extend_BW represents the bandwidth extension factor corresponding to the first data symbol; Roll_off represents the roll-off factor corresponding to the first data symbol. Num *(1+Roll off ) represents the total bandwidth length of the first data symbol after bandwidth extension.

[0176] The purpose of the above formula is to obtain a first length that can make the PAPR of the pilot symbol optimal (eg, lowest), and the first length is as close as possible to the total bandwidth length of the first data symbol after bandwidth expansion.

[0177] Based on the above formula, find a, b, and c that minimize the value of Length_GCS, and based on the obtained a, b, and c, get the first length 2 a 10 b 26 c .

[0178] The above design can make the PAPR of the data symbols reach the optimum (eg, the lowest).

[0179] In another possible implementation, the first length is: under the constraints of the transmission bandwidth of the first data symbol and the first parameter, the PAPR of the pilot symbol is less than the PAPR of the first data symbol, and the first length is equal to 2 a 10 b 26 c The maximum length of

[0180] In other words, the PAPR of the pilot symbol is not based on the pursuit of being optimal, but the PAPR of the pilot symbol only needs to be less than or equal to the PAPR of the first data symbol. In this case, the length that meets the requirement can be within a range, and the maximum length within the range is selected as the first length.

[0181] In a specific implementation, two afas, such as afa1 and afa2, may be determined based on the PAPR range, corresponding to two extreme values ​​of the PAPR range respectively, and then the value of the first length may be solved based on afa1 and afa.

[0182] Exemplarily, the first length (ie, N) satisfies the following conditions simultaneously:

[0183] 1) N = 2 a 10 b 26 c ;

[0184] 2)N≥abs(Data_Num*Extend_BW*afa1);

[0185] afa1 corresponds to the minimum PAPR of the pilot symbol, that is, under the constraints of the transmission bandwidth of the first data symbol and the bandwidth extension factor used to generate the first data symbol, the first length obtained based on afa1 can make the PAPR of the pilot symbol reach (such as the minimum).

[0186] 3)N≤abs(Data_Num*Extend_BW*afa2);

[0187] afa2 corresponds to the PAPR of the first data symbol, that is, under the constraints of the transmission bandwidth of the first data symbol and the bandwidth extension factor used to generate the first data symbol, the first length obtained based on afa2 can make the PAPR of the pilot symbol reach the PAPR of the first data symbol.

[0188] 4) Length GCS =min (a,b,c) (abs(Data Num *(1+Roll off )*afa-2 a 10 b 26 c ));

[0189] Among them, Data Num *(1+Roll off ) represents the total bandwidth length of the first data symbol after bandwidth extension, afa corresponds to the actual PAPR of the pilot symbol, Data Num *(1+Roll off)*afa represents the total bandwidth length of the pilot symbol after bandwidth extension.

[0190] The meaning of the above four formulas is to find the first length that can make the PAPR of the pilot symbol within a PAPR range, and the first length is as close as possible to the total bandwidth length of the first data symbol after bandwidth extension.

[0191] The above design can better support channel estimation in multi-antenna scenarios while satisfying the requirement that the PAPR of the pilot symbol is less than the PAPR of the first data symbol. This is because a longer first sequence pair provides more options for time-domain cyclic shifting for multiple antennas.

[0192] Through the above implementation method, the first terminal device can determine the first length based on the transmission bandwidth of the first data symbol and the first parameter, which can reduce transmission overhead.

[0193] It can be understood that the first length N and the transmission bandwidth M of the first data symbol determined in the embodiment of the present application may be the same or different.

[0194] In some embodiments, the first length N is greater than or equal to a transmission bandwidth M of the first data symbol.

[0195] For example, N is equal to 2 a 10 b 26 c , where N is the smallest integer greater than or equal to M, and a, b, and c are natural numbers; or,

[0196] For example, N is equal to 2 a 10 b , where N is the smallest integer greater than or equal to M, and a and b are natural numbers; or,

[0197] For example, N is equal to 2 a , and N is the smallest integer greater than or equal to M, and a is a natural number.

[0198] N equals 2 a 10 b 26 c , and N is the smallest integer greater than or equal to M. For example: M = 600 REs, the value range of the first length should be [0, 600]. In order to optimize the channel estimation, the length should be as long as possible. According to 2 a 10 b 26 c , the optional lengths around 600 are 512, 520, and 640, as shown in Table 3. Then the maximum value less than or equal to 600 can be selected. Based on this criterion, the first length is 520.

[0199] In some other embodiments, the first length N is less than or equal to the transmission bandwidth M of the first data symbol.

[0200] For example, N is equal to 2 a 10 b 26 c , where N is the largest integer less than or equal to M, and a, b, and c are natural numbers; or,

[0201] For example, N is equal to 2 a 10 b , where N is the largest integer less than or equal to M, and a and b are natural numbers; or,

[0202] For example, N is equal to 2 a , and N is the largest integer less than or equal to M, and a is a natural number.

[0203] N equals 2 a 10 b 26 c , and N is the largest integer less than or equal to M. For example: M = 600 REs, the value range of the first length should be [600, +∞]. In order to reduce the channel estimation overhead, the length should be as short as possible. According to 2 a 10 b 26 c , the optional lengths around 600 are 512, 520, and 640, as shown in Table 3. Then the minimum value greater than or equal to 600 can be selected. Based on this criterion, the first length is 640.

[0204] Table 3

[0205] S302, determining a first sequence pair according to the first length;

[0206] Determining the first sequence pair according to the first length may also be described as: generating the first sequence pair according to the first length.

[0207] Optionally, the first sequence pair is a Golay complementary sequence pair. Further, optionally, the first sequence pair is a binary Golay complementary sequence pair. The binary Golay complementary sequence can lower the PAPR of the ultimately generated pilot signal.

[0208] The first sequence pair includes at least two sequences, and the length of each sequence in the at least two sequences is the first length.

[0209] As an example, determining the first sequence pair according to the first length may be generating the first sequence pair based on an identity document (ID) of a user or a cell and the first length.

[0210] The following generates a length of 2 N1 (2N1 The first sequence pair (representing the first length) is taken as an example:

[0211] Step 1: Generate C init :

[0212] Among them, C init It is a random number related to the user (or cell) ID and is used to distinguish different users (or cells). Indicates the scrambling ID of the DMRS configured by the higher layer; n s Indicates the index of the time slot number in the frame; l indicates the OFDM symbol index in a time slot; Indicates the initial value offset of the DMRS ID (0 or 1); SCID is the scrambling ID, that is, the scrambling code for different IDs.

[0213] In the following, C init =10 as an example.

[0214] Step 2: C init Changing to binary form, we get the generating function:

[0215] Get a binary vector of length N1

[0216] x=dec2bin(0:2 N1 -1), x is The binary number matrix of ;

[0217] Generating function:

[0218] Step 3: Get the length Golay complementary sequence pair, taking a Golay complementary sequence pair including two Golay complementary sequences as an example: r(2n)=(-1).^f(x); r(2n+1)=(-1).^(f(x)+(x:,1)).

[0219] S303. Generate at least two pilot symbols based on the first sequence pair;

[0220] In one possible implementation, if the first length N (i.e., the length of the sequence in the first sequence pair) is less than the transmission bandwidth M, each sequence in the first sequence pair can be extended to the same length as the transmission bandwidth to obtain an extended first sequence pair; and then at least two pilot symbols are generated based on the extended first sequence pair.

[0221] As an example, the sequences in the first sequence pair can be extended in the frequency domain, that is, DFT is performed on any sequence in the first sequence pair; and cyclic extension is performed on any sequence after DFT to extend the length of any sequence after DFT from N to M.

[0222] As shown in Figure 4, the first sequence pair includes a sequence A of length N. First, DFT is performed on sequence A to obtain a frequency domain sequence a of length N; then, cyclic extension is performed on sequence a to obtain a frequency domain sequence a1 of length M. The cyclic extension process is as follows: the last value of the original sequence a, which is of length (MN) / 2, is copied to the front of sequence a, and the first value of the original sequence a, which is of length (MN) / 2, is copied to the back of sequence a, to obtain a frequency domain sequence a1 of length M: a1 = [a(N-(MN) / 2+1), a(N-(MN) / 2+2)…a(N), a(1)…a(N), a(1), a(2)…a(MN / 2)].

[0223] It can be understood that FIG4 is only an example, and the actual cyclic extension method is not limited thereto.

[0224] As another example, the sequences in the first sequence pair can be extended in the time domain, that is, before performing DFT on any sequence in the first sequence pair, zeros are padded in any sequence, and the number of padded zeros is MN, so as to extend the length of any sequence from N to M.

[0225] The position of the zero padding may be to fill zeros at the beginning of the sequence, or to fill zeros at the end of the sequence, or to fill zeros at equal intervals between elements in the sequence, etc., without limitation.

[0226] For example, for a sequence A of length N, A = [a(1), a(2)…a(N)], sequence A is padded with zeros to obtain a sequence a2 of length M: a2 = [0, 0, 0…0, a(1), a(2)…a(N)] or [a(1), a(2)…a(N), 0, 0…0] or [a(1), 0, a(2), 0…a(N-1), 0, a(N)], etc.

[0227] The first length in S302 is 2. N1 For example, after step 3 above, you can also perform step 4:

[0228] Step 4: If the final sequence length (ie, transmission bandwidth) is required For example, M=2 N1 *C N2 , where C N2 If is a positive integer, the following formula can be used to expand the sequence N2 times so that the length of the expanded sequence is 2 N1*C N2 : r′(2n)=a⊙(r(2n)+r(2n+1)) / 2+b⊙(r(2n)+r(2n+1)) / 2; r′(2n+1)=a⊙(r(2n)+r(2n+1)) / 2-b⊙(r(2n)+r(2n+1)) / 2;

[0229] Here, ⊙ is the Kronecker product, which refers to the operation of matrices of any size; for example, N2=10, a=[1-1-1-1-1-1-1-1-1], b=[1-1-1-1-1-1-1-1-1 1-1].

[0230] In another possible implementation, if the first length N (i.e., the length of the sequence in the first sequence pair) is greater than the transmission bandwidth M, each sequence in the first sequence pair may be truncated to obtain a truncated first sequence pair; and at least two pilot symbols are generated based on the truncated first sequence pair. Optionally, the length of the truncated sequence is M.

[0231] The truncation method can be to truncate the first (NM) elements of the sequence, or to truncate the last (NM) elements of the sequence, or to truncate (NM) elements from the sequence at equal intervals, etc., without limitation. For example, the first sequence pair includes a sequence A of length N, A = [a(1), a(2), a(3) ... a(N)]. The truncated sequence can be: a1 = [a((NM)+1), a((NM)+2), ... a(N)] or [a(1), a(2), ... a(M)] or [a(1), a(3), a(5) ... a(M)], etc.

[0232] S304. Output at least two pilot symbols.

[0233] Outputting at least two pilot symbols may refer to outputting N pilot symbols to a processing unit (such as an intermediate frequency), or may refer to sending at least two pilot symbols through a carrier, which is not limited in the embodiment of the present application.

[0234] In the above S301 to S304, the length of the sequence used to generate the pilot symbols (i.e., the first length) is taken into consideration when generating the pilot symbols, and a variety of implementation methods for determining the first length are provided. This allows the generation of pilot symbols based on sequence pairs of appropriate lengths, so that the bandwidth occupied by the generated pilot symbols matches (e.g., is consistent with) the bandwidth occupied by the data symbols, thereby ensuring that the receiving end can effectively estimate all channels that need to be estimated without increasing additional channel estimation overhead. Therefore, the technical effect of balancing the overhead and effectiveness of channel estimation can be achieved.

[0235] In one possible design, the pilot symbols with complementary properties use the same spectrum extension. Exemplarily, the filters used to generate each of the at least two pilot symbols are the same, and / or the bandwidth extension factors used to generate each of the at least two pilot symbols are the same.

[0236] In this way, pilot symbols with complementary properties can be generated or processed based on the same filter, providing support conditions for the receiving end to jointly process the pilot symbols with complementary properties.

[0237] In one possible design, pilot symbols within the same time domain window (TDW) use the same spectrum extension. A TDW is a time block used for (joint) pilot enhancement processing. In other words, the pilot symbol receiver (e.g., a second communication device) can perform (joint) channel estimation on the pilot symbols within the TDW. There is no uplink / downlink switching within the TDW, and / or symbol transmission within the TDW meets phase continuity and power continuity requirements.

[0238] Exemplarily, the at least two pilot symbols are located in the first TDW, the filters used to generate the multiple pilot symbols in the first TDW are the same, and / or the bandwidth extension factors used to generate the multiple pilot symbols in the first TDW are the same.

[0239] In this way, the pilot symbols in the TDW can be generated or processed based on the same filter, providing support conditions for the receiving end to perform joint processing on the pilot symbols in the TDW.

[0240] In one possible design, the pilot symbols and the data symbols use the same spectrum extension. Exemplarily, the filter used to generate the at least two pilot symbols is the same as the filter used to generate the first data symbol; and / or the bandwidth extension factor used to generate the at least two pilot symbols is the same as the bandwidth extension factor used to generate the first data symbol.

[0241] In this way, pilot symbols and data symbols can be generated or processed based on the same filter without distinguishing between pilot symbols and data symbols, thereby enabling transparent transmission and reducing the complexity of signal processing.

[0242] The pilot transmission method on the first communication device side is introduced above, and the pilot transmission method on the second communication device side is introduced below.

[0243] Referring to Figure 5, an embodiment of the present application also provides a pilot transmission method. The method can be performed by a second communication device. Unless otherwise specified, the "second communication device" in this application can refer to the second communication device itself (for example, the network device or terminal device shown in Figure 2), or a component in the second communication device (for example, a processor, a chip, or a chip system, etc.), or a logic module or software that can implement all or part of the functions of the second communication device. The method includes:

[0244] S501, obtaining a signal to be decoded;

[0245] The signal to be decoded includes at least two pilot symbols, which are generated based on a first sequence pair. The first sequence pair includes at least two sequences, and the length of each sequence in the at least two sequences is the first length.

[0246] Regarding the specific design of the first length, reference may be made to the relevant description in the embodiment shown in FIG3 above, which will not be repeated here.

[0247] S502: Perform channel estimation on at least two pilot symbols.

[0248] In some embodiments, the second communications device may perform channel estimation on each of the at least two pilot symbols separately.

[0249] In some other embodiments, the second communications device may perform (joint) channel estimation on at least two pilot symbols.

[0250] Exemplarily, referring to FIG6 , a specific implementation method for performing (joint) channel estimation on at least two pilot symbols may be as follows:

[0251] 1) The second communication device receives time-domain pilot symbols y1 and y2, which correspond to pilot symbols x1 and x2 that traveled through the channel to reach the receiver. The received signals can be expressed as: y1 = h⊙x1+n, y2 = h⊙x2+n, where ⊙ represents circular convolution and n is noise. The noise is subsequently ignored.

[0252] 2) Perform FFT on the time domain pilot symbols y1 and y2 to obtain the frequency domain received signal: Y1 = FFT(y1) = HX1; Y2 = FFT(y2) = HX2;

[0253] Where X1 is the frequency domain signal of pilot symbol #1, and X2 is the frequency domain signal of pilot symbol #2. Pilot symbols #1 and #2 are generated by a pair of complementary Golay sequences (the generation process may involve zero padding, replication, multiplication by a pulse shaping filter, and other operations).

[0254] 3) Multiply Y1 and Y2 by the conjugate of the known signals X1 and X2 and add them: X1*Y1+X2*Y1=X1*X1H+X2*X2H=AH;

[0255] Since X1 and X2 are generated by a Gray complementary sequence pair, for any subcarrier in the frequency domain, the following property holds: X1(n)*X1(n)+X2(n)*X2(n)=A(n);

[0256] Where n represents the frequency domain subcarrier index. Generally speaking, if there is no zero padding or duplication, multiplication by a pulse shaping filter, or other operations, for any n, A(n) = 2. However, considering that zero padding or duplication, multiplication by a pulse shaping filter, or other operations may have been performed, A(n) is not necessarily strictly equal to 2. Instead, the second communication device considers the frequency domain data to be multiplied by the same coefficient A. That is, for the data signal within the TDW, the frequency domain received signal is: Y3 = AHX3;

[0257] Therefore, AH obtained by multiplying Y1 and Y2 by the conjugate of the known signals X1 and X2 and adding them together can be used to equalize Y3 to obtain the transmitted data signal X3.

[0258] The above 1) to 3) are (joint) channel estimation processes performed based on one Golay complementary sequence pair. In practical applications, it is also possible to consider that there may be multiple Golay complementary pairs, and (joint) channel estimation is performed based on multiple Golay complementary sequence pairs.

[0259] In the above S501 to S502, the pilot symbols received by the second communication device are generated based on the first sequence pair, which can effectively estimate all channels that need to be estimated without increasing additional channel estimation overhead, thus taking into account both the overhead and effectiveness of channel estimation.

[0260] Optionally, the second communication device is a network device, and the first communication device may further send first information indicating the first length to another device, such as the first communication device. In this way, the first communication device may determine a sequence pair according to the length indicated by the second communication device, thereby generating a pilot symbol.

[0261] Optionally, the second communication device may also determine the first length. For example:

[0262] Method 1: receiving information from another network device and determining a first length based on the information;

[0263] Method 2: determining the first length according to the correspondence between the transmission bandwidth, parameters, and length of the data symbol;

[0264] Mode 3: Determine the first length according to the transmission bandwidth of the first data symbol and the first parameter.

[0265] For specific implementation, please refer to the relevant implementation method in the embodiment shown in Figure 3 above, and no further details will be given.

[0266] The method provided by the embodiment of the present application is described above in conjunction with the accompanying drawings, and the device provided by the embodiment of the present application is described below in conjunction with the accompanying drawings.

[0267] Based on the same technical concept, an embodiment of the present application provides a communication device 700, which can be, for example, a satellite, a base station, a terminal, or an access point, or a chip inside a satellite, a base station, a terminal, or an access point. The device 700 includes modules, units, or means corresponding to the method steps in the above method embodiments. The functions, units, or means can be implemented by software or hardware, or the corresponding software implementation can be executed by hardware.

[0268] Exemplarily, referring to FIG. 7 , an apparatus 700 may include a processing module 701 and a transceiver module 702 .

[0269] When the apparatus 700 is located in the first communication device:

[0270] The processing module 701 is configured to determine a first length; determine a first sequence pair based on the first length; wherein the first sequence pair includes at least two sequences, and the length of each sequence in the at least two sequences is the first length; and generate at least two pilot symbols based on the first sequence pair;

[0271] The transceiver module 702 is configured to output at least two pilot symbols.

[0272] When the apparatus 700 is located in the second communication device:

[0273] The transceiver module 702 is configured to obtain a signal to be decoded, wherein the signal to be decoded includes at least two pilot symbols, the at least two pilot symbols are generated based on a first sequence pair, the first sequence pair includes at least two sequences, and the length of each sequence in the at least two sequences is the first length;

[0274] The processing module 701 is configured to perform channel estimation on at least two pilot symbols.

[0275] It should be understood that all relevant contents of each step involved in the above method embodiment can be referred to the functional description of the corresponding functional module and will not be repeated here.

[0276] Based on the same technical concept, referring to FIG8 , an embodiment of the present application further provides a communication device 800, including:

[0277] At least one processor 801; and a communication interface 803 communicatively connected to the at least one processor 801; the at least one processor 801 executes instructions stored in the memory 802, so that the device performs the method steps in the above method embodiment through the communication interface 803.

[0278] Optionally, the memory 802 is located outside the device 800 .

[0279] Optionally, the apparatus 800 includes the memory 802, which is connected to the at least one processor 801 and stores instructions executable by the at least one processor 801. FIG8 uses dashed lines to indicate that the memory 802 is optional for the apparatus 800.

[0280] The processor 801 and the memory 802 may be coupled via an interface circuit or may be integrated together, which is not limited here.

[0281] The specific connection medium between the processor 801, memory 802, and communication interface 803 is not limited in the embodiments of the present application. In Figure 8, the processor 801, memory 802, and communication interface 803 are connected via bus 804. The bus is represented by a bold line in Figure 8. The connection between other components is only for illustrative purposes and is not intended to be limiting. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of illustration, Figure 8 only uses a single bold line, but this does not mean that there is only one bus or only one type of bus.

[0282] The specific connection medium between the processor 801, memory 802, and communication interface 803 is not limited in the embodiments of the present application. In Figure 8, the processor 801, memory 802, and communication interface 803 are connected via bus 804. The bus is represented by a bold line in Figure 8. The connection between other components is only for illustrative purposes and is not intended to be limiting. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of illustration, Figure 8 only uses a single bold line, but this does not mean that there is only one bus or only one type of bus.

[0283] It should be understood that the processors mentioned in the embodiments of the present application can be implemented by hardware or software. When implemented by hardware, the processor can be a logic circuit, an integrated circuit, etc. When implemented by software, the processor can be a general-purpose processor that is implemented by reading software code stored in a memory.

[0284] Exemplarily, the processor may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field programmable gate arrays (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor, etc.

[0285] It should be understood that the memory mentioned in the embodiments of the present application may be a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memories. Among them, the non-volatile memory may be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or a flash memory. The volatile memory may be a random access memory (RAM), which is used as an external cache. By way of example and not limitation, many forms of RAM are available, such as static random access memory (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDR SDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous link dynamic random access memory (SLDRAM), and direct RAM bus random access memory (DR RAM).

[0286] It should be noted that when the processor is a general-purpose processor, DSP, ASIC, FPGA or other programmable logic device, discrete gate or transistor logic device, discrete hardware component, the memory (storage module) can be integrated into the processor.

[0287] It should be noted that the memory described herein is intended to include, but not be limited to, these and any other suitable types of memory.

[0288] Based on the same technical concept, an embodiment of the present application further provides a computer-readable storage medium, including a program or instructions. When the program or instructions are run on a computer, the method in the above method embodiment is executed.

[0289] Based on the same technical concept, an embodiment of the present application further provides a computer program product, including instructions, which, when executed on a computer, enables the method in the above method embodiment to be executed.

[0290] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0291] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the present application. It should be understood that each flow and / or box in the flow chart and / or block diagram, as well as the combination of the flow chart and / or box in the flow chart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device produce a device for implementing the functions specified in one or more flow charts and / or one or more boxes in the block diagram.

[0292] These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce a product including an instruction device that implements the functions specified in one or more processes in the flowchart and / or one or more boxes in the block diagram.

[0293] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, so that the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in one or more processes in the flowchart and / or one or more boxes in the block diagram.

Claims

1. A pilot transmission method, characterized in that: include: determining a first length; Determine a first sequence pair according to the first length; wherein the first sequence pair includes at least two sequences, and the length of each sequence in the at least two sequences is the first length; generating at least two pilot symbols based on the first sequence pair; The at least two pilot symbols are output.

2. The method according to claim 1, characterized in that The first sequence pair is a Golay complementary sequence pair.

3. The method according to claim 1 or 2, characterized in that The determining of the first length comprises: receiving first information from a network device, wherein the first information indicates the first length; The first length is determined according to the first information.

4. The method according to claim 3, characterized in that The first information includes a factor set, and the factor set includes at least one of a first factor, a second factor and / or a third factor; The determining the first length according to the first information includes: The first length is determined according to the set of factors.

5. The method according to claim 4, characterized in that The first factor, the second factor, the third factor and the first length satisfy the following relationship: N=2 a 10 b 26 c ; Among them, N is the first length, a is the first factor, b is the second factor, c is the third factor, and a, b, and c are natural numbers.

6. The method according to claim 1 or 2, characterized in that: The first length is related to a transmission bandwidth of a first data symbol, and the first data symbol and the at least two pilot symbols are mapped on the same frequency domain resources.

7. The method according to claim 6, characterized in that The determining of the first length comprises: According to the correspondence between the transmission bandwidth, parameter, and length of the data symbol, the length corresponding to the transmission bandwidth and the first parameter of the first data symbol is determined, and the determined length is the first length; wherein the parameter includes a roll-off factor and / or a bandwidth extension, and the first parameter includes a roll-off factor and / or a bandwidth extension factor used to generate the first data symbol.

8. The method according to claim 6, characterized in that The determining of the first length comprises: The first length is determined according to a transmission bandwidth of the first data symbol and a first parameter, where the first parameter includes a roll-off factor and / or a bandwidth extension factor used to generate the first data symbol.

9. The method according to claim 8, characterized in that The determining the first length according to the transmission bandwidth of the first data symbol and the first parameter includes: The first length is determined according to the transmission bandwidth of the first data symbol, the roll-off factor used to generate the first data symbol, the first coefficient afa, and the second coefficient; wherein the second coefficient is 2 a 10 b 26 c , said a, said b, and said c are natural numbers; or, The first length is determined according to the transmission bandwidth of the first data symbol, the bandwidth extension factor used to generate the first data symbol, the first coefficient afa, and the second coefficient; wherein the second coefficient is 2 a 10 b 26 c , a, b, and c are natural numbers.

10. The method according to any one of claims 6 to 9, characterized in that: The first length is N, and the transmission bandwidth of the first data symbol is M; N is equal to 2 a 10 b 26 c , wherein N is a maximum integer less than or equal to M, and a, b, and c are natural numbers; or, N is equal to 2 a 10 b , and N is the largest integer less than or equal to M, and a and b are natural numbers; or, N is equal to 2 a , and N is a maximum integer less than or equal to M, and a is a natural number.

11. The method according to claim 10, characterized in that The generating at least two pilot symbols based on the first sequence pair comprises: If N is less than M, each sequence in the first sequence pair is extended to a length that is the same as the transmission bandwidth to obtain an extended first sequence pair; The at least two pilot symbols are generated based on the spread first sequence pair.

12. The method according to claim 11, characterized in that The step of extending each sequence in the first sequence pair to a length equal to the transmission bandwidth comprises: Performing a discrete Fourier transform (DFT) on any sequence in the first sequence pair; Cyclic extension is performed on any sequence after DFT, so as to extend the length of any sequence after DFT from the N to the M.

13. The method according to claim 11, characterized in that The step of extending each sequence in the first sequence pair to a length equal to the transmission bandwidth comprises: Before performing DFT on any sequence in the first sequence pair, zeros are padded in the any sequence, and the number of padded zeros is MN, so as to extend the length of the any sequence from the N to the M.

14. The method according to claim 11, characterized in that The filling of zeros in any of the sequences includes one or more of the following: Filling the header of any of the sequences with zeros; padding any of the sequences with zeros at the end; Zeros are filled evenly between the elements in any of the sequences.

15. The method according to any one of claims 6 to 9, characterized in that: The first length is N, and the transmission bandwidth of the first data symbol is M; N is equal to 2 a 10 b 26 c , and N is the smallest integer greater than or equal to M, and a, b, and c are natural numbers; or, N is equal to 2 a 10 b , and N is the smallest integer greater than or equal to M, and a and b are natural numbers; or, N is equal to 2 a , and N is the smallest integer greater than or equal to M, and a is a natural number.

16. The method according to claim 15, characterized in that The generating at least two pilot symbols based on the first sequence pair comprises: If N is greater than M, each sequence in the first sequence pair is truncated to obtain a truncated first sequence pair; The at least two pilot symbols are generated based on the truncated first sequence pair.

17. The method according to any one of claims 1 to 16, characterized in that: The filters used to generate each pilot symbol in the at least two pilot symbols are the same, and / or the bandwidth extension factors used to generate each pilot symbol in the at least two pilot symbols are the same.

18. The method according to any one of claims 1 to 17, characterized in that: The at least two pilot symbols are located in a time domain window TDW; the filters used to generate the multiple pilot symbols in the TDW are the same, and / or the bandwidth extension factors used to generate the multiple pilot symbols in the TDW are the same.

19. The method according to any one of claims 6 to 16, characterized in that: The filter used to generate the pilot symbol is the same as the filter used to generate the first data symbol; and / or the bandwidth extension factor used to generate the pilot symbol is the same as the bandwidth extension factor used to generate the first data symbol.

20. A pilot transmission method, characterized in that: include: Acquire a signal to be decoded; wherein the signal to be decoded includes at least two pilot symbols, the at least two pilot symbols are generated based on a first sequence pair, the first sequence pair includes at least two sequences, and the length of each sequence in the at least two sequences is a first length; Channel estimation is performed on the at least two pilot symbols.

21. The method of claim 20, wherein: The first sequence pair is a Golay complementary sequence pair.

22. The method according to claim 20 or 21, characterized in that Also includes: First information is sent, where the first information indicates the first length.

23. The method of claim 22, wherein: The first information includes a factor set, and the factor set includes at least one of a first factor, a second factor and / or a third factor.

24. The method of claim 23, wherein: The first factor, the second factor, the third factor and the first length satisfy the following relationship: N=2 a 10 b 26 c ; Among them, N is the first length, a is the first factor, b is the second factor, c is the third factor, and a, b, and c are natural numbers.

25. The method according to any one of claims 22 to 24, characterized in that The first length is related to a transmission bandwidth of a first data symbol, and the first data symbol and the at least two pilot symbols are mapped on the same frequency domain resources.

26. The method of claim 25, wherein: The method further comprises: According to the corresponding relationship between the transmission bandwidth, parameters, and length of the data symbol, the transmission of the first data symbol is determined. The bandwidth and the length corresponding to the first parameter are determined as the first length; wherein the parameter includes a roll-off factor and / or a bandwidth extension, and the first parameter includes a roll-off factor and / or a bandwidth extension factor used to generate the first data symbol.

27. The method of claim 25, wherein: The method further comprises: The first length is determined according to a transmission bandwidth of the first data symbol and a first parameter, where the first parameter includes a roll-off factor and / or a bandwidth extension factor used to generate the first data symbol.

28. The method of claim 27, wherein: The determining the first length according to the transmission bandwidth of the first data symbol and the first parameter includes: The first length is determined according to the transmission bandwidth of the first data symbol, the roll-off factor used to generate the first data symbol, the first coefficient afa, and the second coefficient; wherein the second coefficient is 2 a 10 b 26 c , said a, said b, and said c are natural numbers; or, The first length is determined according to the transmission bandwidth of the first data symbol, the bandwidth extension factor used to generate the first data symbol, the first coefficient afa, and the second coefficient; wherein the second coefficient is 2 a 10 b 26 c , a, b, and c are natural numbers.

29. The method according to any one of claims 25 to 28, characterized in that The first length is N, and the transmission bandwidth of the first data symbol is M; N is equal to 2 a 10 b 26 c , wherein N is a maximum integer less than or equal to M, and a, b, and c are natural numbers; or, N is equal to 2 a 10 b , and N is the largest integer less than or equal to M, and a and b are natural numbers; or, N is equal to 2 a , and N is a maximum integer less than or equal to M, and a is a natural number.

30. The method according to any one of claims 25 to 28, characterized in that The first length is N, and the transmission bandwidth of the first data symbol is M; N is equal to 2 a 10 b 26 c , and N is the smallest integer greater than or equal to M, and a, b, and c are natural numbers; or, N is equal to 2 a 10 b , and N is the smallest integer greater than or equal to M, and a and b are natural numbers; or, N is equal to 2 a , and N is the smallest integer greater than or equal to M, and a is a natural number.

31. A communication device, characterized in that: The method comprises a module for executing the method according to any one of claims 1 to 19, or comprises a module for executing the method according to any one of claims 20 to 30.

32. A communication device, characterized in that: The method comprises a processor and an interface circuit, wherein the interface circuit is electrically coupled to the processor, and the processor causes the method according to any one of claims 1 to 19 to be executed through a logic circuit or by executing a code instruction, or causes the method according to any one of claims 20 to 30 to be executed.

33. A computer-readable storage medium, characterized in that: The storage medium stores a computer program or instruction. When the computer program or instruction is executed, the method according to any one of claims 1 to 19 is executed, or the method according to any one of claims 20 to 30 is executed.

34. A computer program product, characterized in that The method comprises instructions which, when executed on a computer, cause the method according to any one of claims 1 to 19 to be executed, or cause the method according to any one of claims 20 to 30 to be executed.

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