Channel estimation method and apparatus, storage medium, terminal device, network device

Abstract

The application provides a channel estimation method and device, a storage medium, a terminal device and a network device. The channel estimation method comprises the following steps: obtaining an initial channel estimation sequence of each pilot point on a pilot symbol; calculating an equivalent time delay of a rectangular spectrum according to the initial channel estimation sequence, wherein the equivalent time delay is obtained by weighted summation of a time delay window length and a difference between a maximum multipath time delay and the time delay window length; constructing a weight matrix by using the equivalent time delay and subcarrier information on the pilot symbol; and calculating a channel estimation value of the pilot symbol according to the weight matrix and the initial channel estimation sequence. The application can reduce the operation amount of channel estimation and improve the accuracy of channel estimation.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of communication, in particular to a channel estimation method and device, storage medium, terminal device and network device. BACKGROUND

[0002] In a wireless communication environment, due to the reflection, scattering and other influences of buildings and ground on radio waves, the time of a transmitted signal reaching a receiver along different transmission paths is different, which causes the mobile channel to be dispersed in time, i.e. time delay spread. After a signal passes through a multipath time delay spread channel, frequency selective fading is formed, and frequency domain equalization based on a pilot needs to be performed. Therefore, the performance of channel estimation directly affects the performance of a receiver.

[0003] At present, a typical channel estimation method is linear minimum mean square error (LMMSE) channel estimation. The LMMSE channel estimation value is H LMMSE = WH LS , where W represents a weight matrix including a plurality of frequency domain correlation coefficients, and H LS is an initial channel estimation at a pilot position.

[0004] However, each time the weight matrix of LMMSE is constructed, a frequency domain correlation coefficient calculation and a matrix inversion operation are needed, and the matrix inversion operation has a large amount, which leads to a large amount of operation in the channel estimation process. In addition, the frequency domain correlation coefficient is determined by the power and time delay of a multipath channel, and the power and time delay of an actual channel are very difficult to estimate, thereby leading to low accuracy of channel estimation. SUMMARY

[0005] The present application provides a channel estimation method and device, storage medium, terminal device and network device, which can reduce the amount of operation of channel estimation and improve the accuracy of channel estimation.

[0006] In order to achieve the above-mentioned purpose, the present application provides the following technical solutions:

[0007] In a first aspect, a channel estimation method is provided, which includes: obtaining an initial channel estimation sequence of each pilot point on a pilot symbol; calculating an equivalent time delay of a rectangular spectrum according to the initial channel estimation sequence, the equivalent time delay being obtained by weighted summation of a time delay window length and a difference between a maximum multipath time delay and the time delay window length; constructing a weight matrix using the equivalent time delay and subcarrier information on the pilot symbol; and calculating a channel estimation value of the pilot symbol according to the weight matrix and the initial channel estimation sequence.

[0008] Optionally, the calculating the equivalent time delay according to the initial channel estimation sequence comprises: obtaining a signal-to-noise ratio, and calculating a weighting coefficient according to the signal-to-noise ratio, the greater the signal-to-noise ratio, the greater the weighting coefficient; and calculating a sum of the time delay window length and a product of the difference value and the weighting coefficient as the equivalent time delay.

[0009] Optionally, the weighting coefficient is calculated by using the following formula: wherein, α represents the weighting coefficient, max() represents a maximum value function, and SNR represents the signal-to-noise ratio.

[0010] Optionally, the constructing a weight matrix by using the equivalent time delay and subcarrier information on the pilot symbol comprises: calculating an autocorrelation frequency domain correlation coefficient by using the equivalent time delay and a distance between two pilot points on the pilot symbol to obtain an autocorrelation matrix; calculating a cross-correlation frequency domain correlation coefficient by using the equivalent time delay and a distance between a pilot point and a data point on the pilot symbol to obtain a cross-correlation matrix; constructing a first weight matrix by using the autocorrelation matrix, and constructing a second weight matrix by using the cross-correlation matrix, the first weight matrix being used for estimating a pilot point channel estimation value, and the second weight matrix being used for estimating a data point channel estimation value.

[0011] Optionally, the autocorrelation frequency domain correlation coefficient or the cross-correlation frequency domain correlation coefficient is calculated by using the following formula: wherein, R(Δk) represents the autocorrelation frequency domain correlation coefficient or the cross-correlation frequency domain correlation coefficient, sinc represents a sine function, Δk represents a distance between two pilot points on a subcarrier when R(Δk) is the autocorrelation frequency domain correlation coefficient, Δk represents a distance between a data point and a pilot point on a subcarrier when R(Δk) is the cross-correlation frequency domain correlation coefficient, and Δf represents a subcarrier interval. represents the equivalent time delay.

[0012] Optionally, the calculating the channel estimation value of the pilot symbol according to the weight matrix and the initial channel estimation sequence comprises: estimating the pilot point channel estimation value by using the first weight matrix and the initial channel estimation sequence; estimating the data point channel estimation value by using the second weight matrix and the pilot point channel estimation value; and combining the pilot point channel estimation value and the data point channel estimation value according to a frequency domain position of each pilot point and data point on the pilot symbol to obtain the channel estimation value.

[0013] Optionally, before constructing the weight matrix using the equivalent time delay and the subcarrier information on the pilot symbol, the method also includes: constructing a phase rotation factor using the equivalent time delay; rotating the phase of the initial channel estimation sequence using the phase rotation factor, and the rotated initial channel estimation sequence is used to calculate the channel estimation value.

[0014] Optionally, the phase rotation factor is constructed using the following formula: Among them, e jθ represents the phase rotation factor, k represents the frequency domain subcarrier index value, represents the equivalent time delay, and N is the number of Fourier transform points.

[0015] In the second aspect, the present application also discloses a channel estimation device, which includes: an acquisition module for acquiring an initial channel estimation sequence for each pilot point on the pilot symbol; an equivalent delay calculation module for calculating the equivalent delay of the rectangular spectrum based on the initial channel estimation sequence, wherein the equivalent delay is obtained by weighted summation of the delay window length and the difference between the maximum multipath delay and the delay window length; a weight matrix calculation module for constructing a weight matrix using the equivalent delay and the subcarrier information on the pilot symbol; and a channel estimation module for calculating the channel estimation value of the pilot symbol based on the weight matrix and the initial channel estimation sequence.

[0016] According to a third aspect, a computer-readable storage medium is provided, on which a computer program is stored. The computer program is executed by a processor to execute any one of the methods provided in the first aspect.

[0017] In a fourth aspect, a terminal device is provided, comprising a memory and a processor, wherein the memory stores a computer program that can be run on the processor, and the processor runs the computer program to execute any one of the methods provided in the first aspect.

[0018] In a fifth aspect, a network device is provided, comprising a memory and a processor, wherein the memory stores a computer program that can be run on the processor, and wherein the processor runs the computer program to execute any one of the methods provided in the first aspect.

[0019] In a sixth aspect, a computer program product is provided, on which a computer program is stored, and the computer program is executed by a processor to perform any one of the methods provided in the first aspect.

[0020] In a seventh aspect, an embodiment of the present application further provides a chip (or a data transmission device) on which a computer program is stored, and when the computer program is executed by the chip, the steps of the above method are implemented.

[0021] In an eighth aspect, the embodiments of the present application further provide a system chip applied to a terminal, the chip system comprising at least one processor and an interface circuit, the interface circuit and the at least one processor being interconnected through a line, and the at least one processor being configured to execute instructions to perform any of the methods provided in the first aspect.

[0022] Compared with the prior art, the technical scheme of the embodiments of the present application has the following beneficial effects:

[0023] In the technical scheme of the present application, the equivalent time delay of the rectangular spectrum is calculated according to the initial channel estimation sequence, the equivalent time delay being obtained by weighting the time delay window length and the difference between the maximum multipath time delay and the time delay window length, the weight matrix is constructed by using the equivalent time delay and the subcarrier information on the pilot symbol, and the channel estimation value of the pilot symbol is calculated according to the weight matrix and the initial channel estimation sequence. In the present application, the weight matrix is constructed by using the estimated equivalent time delay of the rectangular spectrum, which can ensure that the frequency domain correlation coefficients in the weight matrix are closer to the performance of the real channel, thereby ensuring the accuracy of the channel estimation. In addition, the correlation coefficients calculated by the rectangular spectrum are all real numbers, which greatly reduces the calculation amount of the channel estimation and improves the efficiency of the channel estimation.

[0024] Further, in the technical scheme of the present application, the signal-to-noise ratio is obtained, and the weighting coefficient is calculated according to the signal-to-noise ratio, the larger the signal-to-noise ratio, the larger the weighting coefficient; and the sum of the time delay window length and the product of the difference and the weighting coefficient is calculated as the equivalent time delay. In the present application, the equivalent time delay of the rectangular spectrum is adjusted by the signal-to-noise ratio, and the equivalent time delay can reflect the actual channel characteristics, thereby ensuring the accuracy of the subsequent channel estimation. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 is a flowchart of a channel estimation method provided by the embodiments of the present application;

[0026] Figure 2 is a flowchart of another channel estimation method provided by the embodiments of the present application;

[0027] Figure 3 is a structural schematic diagram of a channel estimation device provided by the embodiments of the present application;

[0028] Figure 4 is a schematic diagram of a specific application scenario provided by the embodiments of the present application;

[0029] Figure 5 is a hardware structural schematic diagram of a channel estimation device provided by the embodiments of the present application. DETAILED DESCRIPTION

[0030] The communication system to which the embodiments of the present application are applicable includes, but is not limited to, a Long Term Evolution (LTE) system, a 5th-Generation (5G) system, a New Radio (NR) system, and a future evolution system or a plurality of communication fusion systems. Among them, the 5G system can be a 5G system in a non-standalone (NSA) mode or a 5G system in a standalone (SA) mode. The technical solutions of the present application are also applicable to different network architectures, including but not limited to a relay network architecture, a dual-link architecture, a vehicle-to-anything (V2X) architecture, and the like.

[0031] The network device in the embodiments of the present application can also be referred to as an access network device, for example, a base station (BS) (also referred to as a base station device). The network device is a device deployed in a radio access network (RAN) to provide wireless communication functions. For example, in a second-generation (2G) network, devices providing base station functions include base transceiver stations (BTS), in a third-generation (3G) network, devices providing base station functions include NodeB, in a fourth-generation (4G) network, devices providing base station functions include evolved NodeB (eNB), in a wireless local area network (WLAN), devices providing base station functions include access points (AP), in NR, devices providing base station functions include next generation Node Base station (gNB), and continuously evolving NodeB (ng-eNB), wherein the gNB and the terminal device communicate with each other using NR technology, the ng-eNB and the terminal device communicate with each other using evolved universal terrestrial radio access (E-UTRA) technology, and the gNB and the ng-eNB are both connected to a 5G core network. The network device in the embodiments of the present application also includes devices providing base station functions in future new communication systems, etc.

[0032] The terminal equipment in the embodiments of the present application can refer to various forms of access terminals, user units, user stations, mobile stations, mobile stations (Mobile Station, MS), remote stations, remote terminals, mobile devices, user terminals, wireless communication devices, user agents or user devices. The terminal equipment can also be a cellular phone, a cordless phone, a Session Initiation Protocol (SIP) phone, a Wireless Local Loop (WLL) station, a Personal Digital Assistant (PDA), a handheld device with wireless communication function, a computing device or other processing device connected to a wireless modem, a vehicle-mounted device, a wearable device, a terminal equipment in a future 5G network or a terminal equipment in a future evolved Public Land Mobile Network (PLMN), etc. The embodiments of the present application are not limited thereto. The terminal equipment can also be referred to as user equipment (User Equipment, UE), terminal, etc.

[0033] As described in the background, a frequency domain correlation coefficient calculation and a matrix inversion operation are required once for constructing the weight matrix of LMMSE each time, and the matrix inversion operation has a large amount, resulting in a large amount of operation in the channel estimation process. In addition, the frequency domain correlation coefficient is determined by the power and delay of the multipath channel, and the power and delay of the actual channel are very difficult to estimate, thereby resulting in low accuracy of channel estimation.

[0034] The present application uses the estimated equivalent delay of the rectangular spectrum to construct the weight matrix, which can ensure that the frequency domain correlation coefficient in the weight matrix is closer to the performance of the real channel, thereby ensuring the accuracy of channel estimation. In addition, the correlation coefficient of the rectangular spectrum calculation is all real numbers, which greatly reduces the calculation amount of channel estimation and improves the efficiency of channel estimation.

[0035] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0036] Referring to Figure 1 The method provided by the present application comprises:

[0037] Step 101: obtaining pilot point channel estimation values of each pilot point on the pilot symbol;

[0038] Step 102: calculating the equivalent delay of the rectangular spectrum according to the initial channel estimation sequence, the equivalent delay being obtained by weighted summation of the delay window length and the difference between the maximum multipath delay and the delay window length;

[0039] Step 103: constructing a weight matrix by using the equivalent time delay and the subcarrier information on the pilot symbol;

[0040] Step 104: calculating the channel estimation value of the pilot symbol according to the weight matrix and the initial channel estimation sequence.

[0041] It should be noted that the serial numbers of the steps in the embodiment do not represent the limitation of the execution order of the steps.

[0042] It can be understood that, in a specific implementation, the channel estimation method can be realized in the form of a software program running in a processor integrated in a chip or a chip module. The method can also be realized in the form of software combined with hardware, and the present application does not make any limitation.

[0043] The channel estimation in the embodiment can be the estimation of an uplink channel or the estimation of a downlink channel.

[0044] For a receiver of a terminal device or a network device, a pilot symbol can be received, the pilot symbol including pilot points and data points, the pilot points and the data points being located on different subcarriers. Since the pilot points are agreed in advance by the terminal device and the network device, the pilot points can be received at correct positions, and the received pilot points and the original pilot points can be used to determine an initial channel estimation sequence of the pilot points.

[0045] In a specific implementation of step 101, the initial channel estimation sequence is calculated according to the received pilot signal and the transmitted pilot signal.

[0046] The specific implementation of calculating the channel estimation value of the pilot points by using the received pilot signal and the transmitted pilot signal can refer to the prior art, and the present application does not make any limitation.

[0047] In a specific implementation of step 102, the equivalent time delay of the rectangular spectrum can be calculated according to the initial channel estimation sequence.

[0048] Compared with the prior art of constructing a rectangular spectrum by using a maximum multipath time delay, the calculated frequency domain correlation coefficient is much smaller than the actual one, thereby causing a larger channel estimation error. The present application considers the actual channel energy distribution, constructs a weight matrix by using the estimated equivalent time delay of the rectangular spectrum, can ensure that the frequency domain correlation coefficient in the weight matrix is closer to the performance of the real channel, thereby ensuring the accuracy of the channel estimation; in addition, the correlation coefficient calculated by the rectangular spectrum is a real number, which greatly reduces the calculation amount of the channel estimation and improves the efficiency of the channel estimation.

[0049] In one embodiment, the initial channel estimation sequence is inverse Fourier transformed to obtain a time-domain channel estimation sequence. A first path threshold and an effective path threshold are calculated based on the time-domain channel estimation sequence, and a first path position, an effective path position index and a maximum multipath time delay are calculated based on the first path threshold and the effective path threshold. Further, a time delay window is calculated based on the effective path set. The time delay window can be selected according to specific conditions, for example, a time delay window accounting for 70% to 90% of the total energy.

[0050] In this embodiment, the equivalent time delay is obtained by weighted summation of the time delay window length and the difference between the maximum multipath time delay and the time delay window length. Specifically, the equivalent time delay is calculated using the following formula: wherein a is a weighting coefficient, W is the time delay window, T maxdelay is the maximum multipath time delay, is the equivalent time delay of the rectangular spectrum.

[0051] Specifically, the weighting coefficient is calculated using the following formula:

[0052]

[0053] wherein max() represents a maximum value function, and SNR represents a signal-to-noise ratio. When the signal-to-noise ratio SNR≤1, the equivalent time delay is the time delay window length:

[0054] In one embodiment, the equivalent time delay is used for gear division. If the gear divided by the currently calculated equivalent time delay is the same as the historical gear, the historical weight matrix is used.

[0055] Continuing to refer to Figure 1 In the specific implementation of step 103, a weight matrix W is constructed using the equivalent time delay and the subcarrier information on the pilot symbols. The weight matrix W is used for channel estimation.

[0056] Referring to Figure 2 The specific process of constructing the weight matrix is as follows:

[0057] Step 201: Calculate the autocorrelation frequency domain correlation coefficient using the equivalent time delay and the distance between every two pilot points on the pilot symbols to obtain an autocorrelation matrix R HH .

[0058] Specifically, the autocorrelation frequency domain correlation coefficient of every two pilot points is calculated using the following formula:

[0059] wherein sinc represents a sine function, Δk represents the distance between the subcarriers on which the two pilot points are located, for example, the difference between the subcarrier indexes; Δf represents the subcarrier spacing, represents the equivalent time delay. For example,

[0060] auto-correlation matrix R HH each element in the auto-correlation matrix R is an auto-correlation frequency domain correlation coefficient of each two pilot points.

[0061] Step 202: calculating cross-correlation frequency domain correlation coefficients by using the equivalent time delay and the distance between the pilot point and the data point on the subcarrier, to obtain a cross-correlation matrix R DH .

[0062] Specifically, the cross-correlation frequency domain correlation coefficients of the pilot point and the data point are calculated by using the following formula:

[0063] wherein, Δk represents the distance between the data point and the pilot point on the subcarrier.

[0064] cross-correlation matrix R DH each element in the cross-correlation matrix R is a cross-correlation frequency domain correlation coefficient of each pilot point and each data point.

[0065] Step 203: constructing a first weight matrix by using the auto-correlation matrix, and constructing a second weight matrix by using the cross-correlation matrix.

[0066] Specifically, the calculation formula of the first weight matrix W1 is as follows: wherein, R HH represents the auto-correlation matrix, and SNR represents the signal-to-noise ratio.

[0067] The calculation formula of the second weight matrix W2 is as follows: wherein, R HH represents the auto-correlation matrix, and R DH represents the cross-correlation matrix.

[0068] In the embodiment, the first weight matrix W1 can be used for channel estimation of the pilot point, and the second weight matrix W2 can be used for channel estimation of the data point.

[0069] Specifically, the order of the linear minimum mean square error (LMMSE) is adaptively selected according to the equivalent time delay, and the order of the LMMSE weight is smaller when the equivalent time delay is larger.

[0070] In one non-limiting embodiment, a phase rotation factor is constructed by using the equivalent time delay; the phase of an initial channel estimation sequence is rotated by using the phase rotation factor, and the rotated initial channel estimation sequence is used for calculating the channel estimation value.

[0071] Specifically, the phase rotation factor is constructed by using the following formula:

[0072] wherein, e jθdenotes a phase rotation factor, k denotes a frequency domain subcarrier index value, denotes the equivalent delay, N is a Fourier transform point number.

[0073] According to the phase rotation factor e jθ An initial channel estimation sequence H LS is subjected to phase rotation to obtain a phase-rotated sequence H' LS The phase-rotated sequence H' LS is multiplied by a first weight matrix W1 to obtain a pilot point channel estimation value H1' LMMSE =W1H' LS .

[0074] Correspondingly, the pilot point channel estimation value H1' LMMSE is multiplied by a second weight matrix W2 to obtain a data point channel estimation value H2' LMMSE =W2H1' LMMSE The pilot point channel estimation value H1' LMMSE and the data point channel estimation value H2' LMMSE are combined to obtain a channel estimation value H' LMMSE .

[0075] Further, the channel estimation value H' LMMSE is subjected to de-phase rotation by using a phase rotation factor e jθ to obtain a pilot symbol channel estimation value H LMMSE .

[0076] In the embodiment, the phase rotation factor is calculated according to the equivalent delay instead of half of the maximum delay, so that the power delay spectrum after shifting satisfies the energy symmetry. Therefore, by using the embodiment, the system can flexibly obtain the optimal weight coefficient, improve the channel estimation performance, and reduce the channel estimation calculation complexity.

[0077] Up to now, the channel estimation process has been completed, and the pilot symbol channel estimation value H LMMSE can be used for receiving subsequent signals.

[0078] For more specific implementation manners of the embodiment, refer to the foregoing embodiment, which will not be described here.

[0079] Please refer to Figure 3 , Figure 3 shows a channel estimation device 30, which can include:

[0080] The acquisition module 301 is configured to acquire an initial channel estimation sequence of each pilot point on a pilot symbol.

[0081] The equivalent delay calculation module 302 is configured to calculate an equivalent delay of the rectangular spectrum according to the initial channel estimation sequence, and the equivalent delay is obtained by weighted summation of the delay window length and the difference between the maximum multipath delay and the delay window length.

[0082] The weight matrix calculation module 303 is configured to construct a weight matrix by using the equivalent delay and the subcarrier information on the pilot symbol.

[0083] The channel estimation module 304 is configured to calculate the channel estimation value of the pilot symbol according to the weight matrix and the initial channel estimation sequence.

[0084] In specific implementation, the channel estimation device 30 can correspond to a chip with a channel estimation function in a terminal device, such as a System-On-a-Chip (SOC), a baseband chip, etc.; or a chip module including a chip with a channel estimation function in a terminal device; or a chip module with a data processing function, or a terminal device.

[0085] In specific implementation, the channel estimation device 30 can also correspond to a chip with a channel estimation function in a network device, such as an SOC, a baseband chip, etc.; or a chip module including a chip with a channel estimation function in a network device; or a chip module with a data processing function, or a network device.

[0086] For other related descriptions of the channel estimation device 30, refer to the related descriptions in Figure 1 or Figure 2 , which will not be described herein again.

[0087] Regarding the various modules / units contained in the various devices and products described in the above embodiments, they can be software modules / units, hardware modules / units, or partly software modules / units and partly hardware modules / units. For example, for various devices and products applied to or integrated into a chip, the various modules / units contained therein can all be implemented in the form of hardware such as circuits, or at least part of the modules / units can be implemented in the form of software programs, which run on the processor integrated inside the chip, and the remaining (if any) modules / units can be implemented in the form of hardware such as circuits; for various devices and products applied to or integrated into a chip module, the various modules / units contained therein can all be implemented in the form of hardware such as circuits, and different modules / units can be located in the same component of the chip module (such as a chip, circuit module, etc.) or in different components, or at least part of the modules / units can be implemented in the form of software programs. It is implemented in the form of a software program, which runs on the processor integrated inside the chip module, and the remaining (if any) modules / units can be implemented in the form of hardware such as circuits; for various devices and products applied to or integrated in the terminal equipment, the various modules / units contained therein can be implemented in the form of hardware such as circuits, and different modules / units can be located in the same component (for example, chip, circuit module, etc.) or different components in the terminal equipment, or, at least some modules / units can be implemented in the form of a software program, which runs on the processor integrated inside the terminal equipment, and the remaining (if any) modules / units can be implemented in the form of hardware such as circuits.

[0088] The present application also discloses a storage medium, which is a computer-readable storage medium having a computer program stored thereon. When the computer program is run, the computer program can execute Figures 1 to 3 The steps of the method shown in . The storage medium may include a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, etc. The storage medium may also include a non-volatile memory (non-volatile) or a non-transitory memory, etc.

[0089] like Figure 4 As shown, Figure 4 This figure shows a comparison of the present invention's solution with various existing channel estimation algorithms. Simulation conditions: Matlab 2020a, 80 resource blocks (RBs), and 30 kHz subcarrier spacing. The horizontal axis represents the signal-to-noise ratio (SNR), and the vertical axis represents the mean square error (MSE).

[0090] In particular, curve 1 represents the simulation result of the Fourier transform (FFT), and curve 2 represents the simulation result of the scheme of the present application. Figure 4 The simulation result of the rectangular spectrum length with the maximum multipath delay (Rect MaxDelay) and the simulation result of the exponential decay spectrum (Exp Delay) are also shown in the figure. As can be seen from the figure, the simulation result of the scheme of the present application is closest to the simulation result of the Fourier transform (FFT).

[0091] Please refer to Figure 5 The embodiment of the present application further provides a hardware structure schematic diagram of a communication device. The device comprises a processor 401, a memory 402 and a transceiver 403.

[0092] The processor 401 can be a general central processing unit (CPU), a microprocessor, an application-specific integrated circuit (ASIC), or one or more integrated circuits for controlling the execution of programs of the scheme of the present application. The processor 401 can also comprise a plurality of CPUs, and the processor 401 can be a single-CPU processor or a multi-CPU processor. The processor herein can refer to one or more devices, circuits or processing cores for processing data (for example, computer program instructions).

[0093] The memory 402 can be a ROM or other type of static storage device that can store static information and instructions, a RAM or other type of dynamic storage device that can store information and instructions, an electrically erasable programmable read-only memory (EEPROM), a compact disc read-only memory (CD-ROM) or other optical disk storage, an optical disk storage (including a compact disk, a laser disc, an optical disc, a digital versatile disc, a Blu-ray disc, etc.), a magnetic disk storage medium or other magnetic storage device, or any other medium that can be used to carry or store desired program codes in the form of instructions or data structures and can be accessed by a computer, and the embodiment of the present application does not make any limitation thereto. The memory 402 can exist independently (at this time, the memory 402 can be located outside the device or inside the device), or can be integrated with the processor 401. The memory 402 can contain computer program codes. The processor 401 is used to execute the computer program codes stored in the memory 402, so as to realize the method provided by the embodiment of the present application.

[0094] The processor 401, the memory 402 and the transceiver 403 are connected by a bus. The transceiver 403 is configured to communicate with other devices or communication networks. Optionally, the transceiver 403 can include a transmitter and a receiver. The device in the transceiver 403 for realizing the receiving function can be regarded as a receiver, and the receiver is configured to perform the steps of receiving in the embodiments of the present application. The device in the transceiver 403 for realizing the sending function can be regarded as a transmitter, and the transmitter is configured to perform the steps of sending in the embodiments of the present application.

[0095] It should be understood that the term "and / or" in this application is only used to describe the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B can represent the three cases of A alone, A and B together, and B alone. In addition, the character " / " in this application represents an "or" relationship between the front and rear associated objects.

[0096] The "multiple" appearing in the embodiments of the present application means two or more.

[0097] The first, second and the like appearing in the embodiments of the present application are only used for description and distinction of the described objects, and there is no order, nor does it represent a special limitation on the number of devices in the embodiments of the present application, which cannot constitute any limitation on the embodiments of the present application.

[0098] The "connection" appearing in the embodiments of the present application means direct connection or indirect connection and various connection modes to realize the communication between devices, which is not limited in the embodiments of the present application.

[0099] The above embodiments can be realized by software, hardware, firmware or any combination thereof, in whole or in part. When realized by software, the above embodiments can be realized in the form of a computer program product in whole or in part. The computer program product includes one or more computer instructions or computer programs. When the computer instructions or computer programs are loaded or executed on a computer, the processes or functions described in the embodiments of the present application are generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network or other programmable devices. The computer instructions can be stored in a computer readable storage medium or transmitted from one computer readable storage medium to another, for example, the computer instructions can be transmitted from one website, computer, server or data center to another website, computer, server or data center through wired or wireless mode.

[0100] It should be understood that in various embodiments of the present application, the size of the serial number of the above processes does not mean the order of execution, and the execution order of the processes should be determined according to its function and inherent logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0101] In several embodiments provided in the present application, it should be understood that the disclosed methods, devices and systems can be implemented in other manners. For example, the described device embodiments are merely illustrative; the division of the units is merely logical function division; and other division manners can be used in actual implementation; for example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the displayed or discussed mutual couplings or direct couplings or communication connections can be indirect couplings or communication connections through some interfaces, devices or units, and can be in electrical, mechanical or other forms.

[0102] The units described as separate components can or can not be physically separate, and the components shown as units can or can not be physical units, i.e., can be located in one place, or can be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purposes of the embodiments.

[0103] In addition, each functional unit in the various embodiments of the present application can be integrated in one processing unit, or each unit can be physically included separately, or two or more units can be integrated in one unit. The integrated unit can be implemented in the form of hardware, or in the form of hardware plus software function units.

[0104] The integrated unit implemented in the form of software function units can be stored in a computer readable storage medium. The software function unit stored in the storage medium includes a plurality of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute some steps of the methods described in the various embodiments of the present application.

[0105] Although the present application is disclosed as above, the present application is not limited thereto. Any person skilled in the art, without departing from the spirit and scope of the present application, can make various modifications and changes, and therefore the protection scope of the present application should be subject to the scope defined by the claims.

Claims

1. A method of channel estimation, characterized by, The method comprises the following steps: obtaining an initial channel estimation sequence of each pilot point on a pilot symbol; calculating an equivalent time delay of a rectangular spectrum according to the initial channel estimation sequence, the equivalent time delay being a weighted sum of a time delay window length and a difference between a maximum multipath time delay and the time delay window length; constructing a weight matrix by using the equivalent time delay and subcarrier information on the pilot symbol; calculating a channel estimation value of the pilot symbol according to the weight matrix and the initial channel estimation sequence; the step of calculating the equivalent time delay of the rectangular spectrum according to the initial channel estimation sequence comprises the following steps: obtaining a signal-to-noise ratio and calculating a weighting coefficient according to the signal-to-noise ratio, the larger the signal-to-noise ratio, the larger the weighting coefficient; calculating a sum of the time delay window length and a product of the difference and the weighting coefficient as the equivalent time delay; the step of constructing the weight matrix by using the equivalent time delay and the subcarrier information on the pilot symbol comprises the following steps: calculating an autocorrelation frequency domain correlation coefficient by using the equivalent time delay and a distance between each two pilot points on the pilot symbol to obtain an autocorrelation matrix; calculating a cross-correlation frequency domain correlation coefficient by using the equivalent time delay and a distance between a pilot point and a data point on the pilot symbol to obtain a cross-correlation matrix; constructing a first weight matrix by using the autocorrelation matrix and a second weight matrix by using the cross-correlation matrix, the first weight matrix being used for estimating a pilot point channel estimation value and the second weight matrix being used for estimating a data point channel estimation value.

2. The channel estimation method of claim 1, wherein, The weighting coefficient is calculated by using the following formula: ， wherein denotes the weighting factor, max() denotes the maximum function, and SNR denotes the signal-to-noise ratio.

3. The channel estimation method of claim 1, wherein The autocorrelation frequency domain correlation coefficient or the cross-correlation frequency domain correlation coefficient is calculated by using the following formula: ， wherein, denotes the autocorrelation frequency-domain correlation coefficient or the cross-correlation frequency-domain correlation coefficient, denotes the sinc function, where for the autocorrelation frequency-domain correlation coefficient, denotes the distance of the two pilot points in the subcarriers, where for the cross-correlation frequency-domain correlation coefficient, denotes the distance of the data point and the pilot point in the subcarriers, denotes the subcarrier spacing, denotes the equivalent time delay.

4. The channel estimation method of claim 1, wherein the step of calculating the channel estimation value of the pilot symbol according to the weight matrix and the initial channel estimation sequence comprises the following steps: estimating the pilot point channel estimation value by using the first weight matrix and the initial channel estimation sequence; estimating the data point channel estimation value by using the second weight matrix and the pilot point channel estimation value; combining the pilot point channel estimation value and the data point channel estimation value according to frequency domain positions of each pilot point and data point on the pilot symbol to obtain the channel estimation value.

5. The method for channel estimation according to claim 1, wherein, Before the step of constructing the weight matrix by using the equivalent time delay and the subcarrier information on the pilot symbol, the method further comprises the following steps: constructing a phase rotation factor by using the equivalent time delay; rotating a phase of the initial channel estimation sequence by using the phase rotation factor, and the rotated initial channel estimation sequence being used for calculating the channel estimation value.

6. The channel estimation method of claim 5, wherein, The phase rotation factor is constructed using the following equation: , wherein denotes a phase rotation factor, k denotes a frequency domain subcarrier index value, denotes the equivalent delay, N is the number of Fourier transform points.

7. A channel estimation apparatus characterized by comprising: The method comprises the following steps: an obtaining module, configured to obtain an initial channel estimation sequence of each pilot point on a pilot symbol; an equivalent time delay calculation module, configured to calculate an equivalent time delay of a rectangular spectrum according to the initial channel estimation sequence, the equivalent time delay being a weighted sum of a time delay window length and a difference between a maximum multipath time delay and the time delay window length; a weight matrix calculation module, configured to construct a weight matrix by using the equivalent time delay and subcarrier information on the pilot symbol; a channel estimation module, configured to calculate a channel estimation value of the pilot symbol according to the weight matrix and the initial channel estimation sequence; the step of calculating the equivalent time delay of the rectangular spectrum according to the initial channel estimation sequence comprises the following steps: the step of calculating the equivalent time delay of the rectangular spectrum according to the initial channel estimation sequence comprises the following steps: obtaining a signal-to-noise ratio and calculating a weighting coefficient according to the signal-to-noise ratio, the larger the signal-to-noise ratio, the larger the weighting coefficient; calculating a sum of the time delay window length and a product of the difference and the weighting coefficient as the equivalent time delay; the step of constructing the weight matrix by using the equivalent time delay and the subcarrier information on the pilot symbol comprises the following steps: calculating an autocorrelation frequency domain correlation coefficient by using the equivalent time delay and a distance between each two pilot points on the pilot symbol to obtain an autocorrelation matrix; calculating a cross-correlation frequency domain correlation coefficient by using the equivalent time delay and a distance between a pilot point and a data point on the pilot symbol to obtain a cross-correlation matrix; constructing a first weight matrix by using the autocorrelation matrix and a second weight matrix by using the cross-correlation matrix, the first weight matrix being used for estimating a pilot point channel estimation value and the second weight matrix being used for estimating a data point channel estimation value. The weighting coefficient is calculated by using the following formula: The autocorrelation frequency domain correlation coefficient or the cross-correlation frequency domain correlation coefficient is calculated by using the following formula: the step of calculating the channel estimation value of the pilot symbol according to the weight matrix and the initial channel estimation sequence comprises the following steps: estimating the pilot point channel estimation value by using the first weight matrix and the initial channel estimation sequence; estimating the data point channel estimation value by using the second weight matrix and the pilot point channel estimation value; combining the pilot point channel estimation value and the data point channel estimation value according to frequency domain positions of each pilot point and data point on the pilot symbol to obtain the channel estimation value. Before the step of constructing the weight matrix by using the equivalent time delay and the subcarrier information on the pilot symbol, the method further comprises the following steps: constructing a phase rotation factor by using the equivalent time delay; rotating a phase of the initial channel estimation sequence by using the phase rotation factor, and the rotated initial channel estimation sequence being used for calculating the channel estimation value. The equivalent delay calculation module is further configured to obtain a signal-to-noise ratio, and calculate a weighting coefficient according to the signal-to-noise ratio, wherein the greater the signal-to-noise ratio is, the greater the weighting coefficient is; and calculate a sum of the delay window length and a product of the difference value and the weighting coefficient as the equivalent delay. The weight matrix calculation module is further configured to calculate an autocorrelation frequency domain correlation coefficient by using the equivalent delay and a distance between every two pilot subcarriers on which pilot symbols are located, to obtain an autocorrelation matrix; and calculate a cross-correlation frequency domain correlation coefficient by using the equivalent delay and a distance between pilot subcarriers and data subcarriers on which pilot symbols and data symbols are located, to obtain a cross-correlation matrix. A first weight matrix is constructed by using the autocorrelation matrix, and a second weight matrix is constructed by using the cross-correlation matrix, wherein the first weight matrix is used to estimate a pilot point channel estimation value, and the second weight matrix is used to estimate a data point channel estimation value.

8. A computer readable storage medium having stored thereon a computer program, characterized in that, The computer program, when executed by a processor, performs the steps of the channel estimation method of any one of claims 1 to 6. 9.A terminal device, comprising a memory and a processor, wherein a computer program is stored on the memory and executable on the processor, and the computer program comprises the following steps of: The processor, when executing the computer program, performs the steps of the channel estimation method of any one of claims 1 to 6.

10. A network device comprising a memory and a processor, said memory having stored thereon a computer program operable to run on said processor, characterized in that, The processor, when executing the computer program, performs the steps of the channel estimation method of any one of claims 1 to 6. The processor, when executing the computer program, performs the steps of the channel estimation method of any one of claims 1 to 6.

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