OFDM signal processing method, transmission system and device

Abstract

The present disclosure provides an OFDM signal processing method, a transmission system, and a device, for use in effectively reducing a peak to average power ratio of OFDM signals. The method comprises: determining the frequency of an OFDM modulation symbol, wherein the OFDM modulation symbol is obtained by performing digital modulation on an OFDM signal; on the basis of a frequency domain function and the frequency of the OFDM modulation symbol, determining a frequency domain function value corresponding to the frequency of the OFDM modulation symbol, wherein the frequency domain function is obtained by performing linear combination on the basis of a linear function and trigonometric functions of different frequencies; on the basis of the frequency domain function value corresponding to the OFDM modulation symbol, determining a coding matrix corresponding to the OFDM signal; and using the coding matrix corresponding to the OFDM signal to process the OFDM signal, so as to obtain a target OFDM signal conforming to a change rule of the frequency domain function.

Description

OFDM signal processing method, transmission system and equipment Technical Field

[0001] The present disclosure relates to the field of wireless communication technology, and in particular to an OFDM signal processing method, transmission system, and device. Background Art

[0002] Orthogonal Frequency Division Multiplexing (OFDM) is a multicarrier modulation technology that divides a carrier into several mutually orthogonal subcarriers to overcome frequency-selective fading and narrowband interference. However, in an OFDM system, the superposition of subcarriers can cause the signal's peak power to be much greater than its average power, resulting in a high PAPR (Peak to Average Power Ratio). Due to power constraints in certain scenarios, a high PAPR can cause out-of-band radiation and in-band distortion in nonlinear transmission channels, leading to signal distortion and increased system bit error rate (BER), reducing the performance of OFDM communication systems.

[0003] Currently, methods for suppressing the peak-to-average ratio (PAR) of OFDM systems include limiting, coding, and probabilistic methods. However, limiting introduces clipping noise, which increases the system's bit error rate and reduces system performance. Coding methods do not distort the signal, but are computationally complex and generate a lot of redundant data. Probabilistic methods are simple and intuitive, but they are computationally intensive and require the transmission of sideband information, increasing the difficulty and cost of system implementation.

[0004] Summary of the Invention

[0005] The present disclosure provides an OFDM signal processing method, transmission system and device, which are used to effectively reduce the PAPR of OFDM signals and improve the communication performance and perception performance of the OFDM system through a simple implementation and probabilistic method without the need to transmit sideband information.

[0006] In a first aspect, an embodiment of the present disclosure provides an OFDM signal processing method, the method comprising:

[0007] Determining a frequency of an OFDM modulation symbol, wherein the OFDM modulation symbol is obtained by digitally modulating an OFDM signal;

[0008] Determining a frequency domain function value corresponding to the frequency of the OFDM modulation symbol based on the frequency domain function and the frequency of the OFDM modulation symbol, wherein the frequency domain function is obtained by linearly combining a linear function and trigonometric functions of different frequencies;

[0009] Determining a coding matrix corresponding to the OFDM signal according to a frequency domain function value corresponding to the OFDM modulation symbol;

[0010] The OFDM signal is processed using a coding matrix corresponding to the OFDM signal to obtain a target OFDM signal that conforms to the variation law of the frequency domain function.

[0011] The OFDM signal processing method provided in this embodiment uses a linear combination of a linear function and trigonometric functions of different frequencies to construct a frequency domain function, uses the frequency domain function values ​​corresponding to the frequencies of the OFDM modulation symbols to construct a coding matrix, and uses the coding matrix to process the entire OFDM signal so that the processed target OFDM signal conforms to the variation pattern of the frequency domain function. The frequency domain function is formed by a linear combination of a linear function and trigonometric functions of different frequencies, which can make the variation pattern of the OFDM signal spectrum meet the requirements of low PAPR. Therefore, by implementing a simple probabilistic method that does not require the transmission of sideband information, the PAPR of OFDM can be effectively reduced, thereby improving not only the communication performance of the OFDM system but also the perception performance.

[0012] As an optional implementation manner, determining the frequency of the OFDM modulation symbol includes:

[0013] Determining a starting frequency, a frequency step value, and an ending frequency of the OFDM modulation symbol according to the bandwidth of the OFDM modulation symbol and a first preset parameter;

[0014] The frequency of the OFDM modulation symbol is determined according to the starting frequency, the frequency step value and the ending frequency.

[0015] As an optional implementation manner, the first preset parameter includes a roll-off factor, a target symbol length, and a first parameter, where the target symbol length is used to represent the length of the OFDM modulation symbol after being processed by the coding matrix;

[0016] Determining a start frequency, a frequency step value, and an end frequency of the OFDM modulation symbol according to the bandwidth of the OFDM modulation symbol and a first preset parameter includes:

[0017] Determining a start frequency and an end frequency according to a bandwidth, a roll-off factor, and a target symbol length of the OFDM modulation symbol;

[0018] A frequency step value is determined according to the bandwidth, roll-off factor and first parameter of the OFDM modulation symbol.

[0019] As an optional implementation manner, determining the frequency domain function value corresponding to the frequency of the OFDM modulation symbol based on the frequency domain function and the frequency of the OFDM modulation symbol includes:

[0020] Determining a first threshold and a second threshold according to the bandwidth and the roll-off factor of the OFDM modulation symbol;

[0021] When the absolute value of the frequency of the OFDM modulation symbol is greater than a first threshold and less than a second threshold, a frequency domain function value corresponding to the frequency of the OFDM modulation symbol is determined based on the frequency domain function and the frequency of the OFDM modulation symbol.

[0022] As an optional implementation manner, the frequency domain function is determined in the following manner:

[0023] According to the respective weights of the linear function and the trigonometric functions of different frequencies, a weighted sum is performed on the linear function and the trigonometric functions of different frequencies to obtain the frequency domain function.

[0024] As an optional implementation manner, the slope of the linear function changes with changes in the bandwidth and roll-off coefficient of the OFDM signal.

[0025] As an optional implementation, the linear function is determined in the following manner:

[0026] Determining a slope according to a bandwidth and a roll-off factor of the OFDM modulation symbol, wherein the slope decreases as the bandwidth and the roll-off factor increase;

[0027] Determining linear function variables according to the bandwidth, roll-off factor, and frequency of the OFDM modulation symbol;

[0028] The first-order linear function is determined according to the slope and the linear function variable.

[0029] As an optional implementation,

[0030] The phases of the trigonometric functions of different frequencies vary with the roll-off factor of the OFDM signal; and / or,

[0031] The amplitude of the trigonometric function increases as the number of the trigonometric functions increases.

[0032] As an optional implementation, the trigonometric function is determined as follows:

[0033] Determining the phase of the trigonometric function according to the roll-off coefficient of the OFDM signal;

[0034] Determining trigonometric function variables based on the bandwidth, roll-off factor, and frequency of the OFDM modulation symbol;

[0035] The trigonometric function is determined based on the phase and the trigonometric function variable.

[0036] As an optional implementation, the frequency domain function is expressed by the following formula: x=Bw·(1+α)-abs(f);

[0037] Among them, C(k) represents the frequency domain function, a0 represents the weight of a linear function, K1 represents the number of sinusoidal functions of different frequencies, and a i represents the weight of the i-th sine function, b i represents the amplitude of the i-th sine function, K2 represents the number of cosine functions of different frequencies, c i represents the weight of the i-th cosine function, d i represents the amplitude of the i-th cosine function, Bw represents the bandwidth of the OFDM modulation symbol, α represents the roll-off coefficient of the OFDM modulation symbol, f represents the frequency of the OFDM modulation symbol, and abs(*) is the absolute value function.

[0038] As an optional implementation, the b i As i increases, b increases. i is an odd number; and / or,

[0039] The d i As i increases, the d i An odd number.

[0040] As an optional implementation manner, determining the coding matrix corresponding to the OFDM signal according to the frequency domain function value corresponding to the OFDM modulation symbol includes:

[0041] Determine the frequency domain function value corresponding to the OFDM modulation symbol as a coding matrix coefficient;

[0042] The coding matrix corresponding to the OFDM signal is determined according to the product value of the coding matrix coefficient corresponding to the OFDM modulation symbol and the phase factor.

[0043] As an optional implementation,

[0044] The phase factor changes in an exponential function as the second preset parameter of the OFDM modulation symbol changes;

[0045] The second preset parameters include a target symbol length and an expansion coefficient, and the target symbol length is used to represent the length of the OFDM modulation symbol after being processed by the coding matrix.

[0046] As an optional implementation manner, the processing of the OFDM signal using the coding matrix corresponding to the OFDM signal to obtain a target OFDM signal that conforms to the frequency domain function change law includes:

[0047] The coding matrix corresponding to the OFDM signal is multiplied by the OFDM signal to obtain a target OFDM signal that conforms to the variation law of the frequency domain function.

[0048] In a second aspect, an embodiment of the present disclosure provides a method for determining a coding matrix, wherein the method includes:

[0049] Determining a frequency of an OFDM modulation symbol, wherein the OFDM modulation symbol is obtained by digitally modulating an OFDM signal;

[0050] Determining a frequency domain function value corresponding to the frequency of the OFDM modulation symbol based on the frequency domain function and the frequency of the OFDM modulation symbol, wherein the frequency domain function is obtained by linearly combining a linear function and trigonometric functions of different frequencies;

[0051] A coding matrix corresponding to the OFDM signal is determined according to a frequency domain function value corresponding to the OFDM modulation symbol.

[0052] As an optional implementation manner, determining the frequency of the OFDM modulation symbol includes:

[0053] Determining a starting frequency, a frequency step value, and an ending frequency of the OFDM modulation symbol according to the bandwidth of the OFDM modulation symbol and a first preset parameter;

[0054] The frequency of the OFDM modulation symbol is determined according to the starting frequency, the frequency step value and the ending frequency.

[0055] As an optional implementation manner, the first preset parameter includes a roll-off factor, a target symbol length, and a first parameter, where the target symbol length is used to represent the length of the OFDM modulation symbol after being processed by the coding matrix;

[0056] Determining a start frequency, a frequency step value, and an end frequency of the OFDM modulation symbol according to the bandwidth of the OFDM modulation symbol and a first preset parameter includes:

[0057] Determining a start frequency and an end frequency according to a bandwidth, a roll-off factor, and a target symbol length of the OFDM modulation symbol;

[0058] A frequency step value is determined according to the bandwidth, roll-off factor and first parameter of the OFDM modulation symbol.

[0059] As an optional implementation manner, determining the frequency domain function value corresponding to the frequency of the OFDM modulation symbol based on the frequency domain function and the frequency of the OFDM modulation symbol includes:

[0060] Determining a first threshold and a second threshold according to the bandwidth and the roll-off factor of the OFDM modulation symbol;

[0061] When the absolute value of the frequency of the OFDM modulation symbol is greater than a first threshold and less than a second threshold, a frequency domain function value corresponding to the frequency of the OFDM modulation symbol is determined based on the frequency domain function and the frequency of the OFDM modulation symbol.

[0062] As an optional implementation manner, the frequency domain function is determined in the following manner:

[0063] According to the respective weights of the linear function and the trigonometric functions of different frequencies, a weighted sum is performed on the linear function and the trigonometric functions of different frequencies to obtain the frequency domain function.

[0064] As an optional implementation manner, the slope of the linear function changes with changes in the bandwidth and roll-off coefficient of the OFDM signal.

[0065] As an optional implementation, the linear function is determined in the following manner:

[0066] Determining a slope according to a bandwidth and a roll-off factor of the OFDM modulation symbol, wherein the slope decreases as the bandwidth and the roll-off factor increase;

[0067] Determining linear function variables according to the bandwidth, roll-off factor, and frequency of the OFDM modulation symbol;

[0068] The first-order linear function is determined according to the slope and the linear function variable.

[0069] As an optional implementation,

[0070] The phases of the trigonometric functions of different frequencies vary with the roll-off factor of the OFDM signal; and / or,

[0071] The amplitude of the trigonometric function increases as the number of the trigonometric functions increases.

[0072] As an optional implementation, the trigonometric function is determined as follows:

[0073] Determining the phase of the trigonometric function according to the roll-off coefficient of the OFDM signal;

[0074] Determining trigonometric function variables based on the bandwidth, roll-off factor, and frequency of the OFDM modulation symbol;

[0075] The trigonometric function is determined based on the phase and the trigonometric function variable.

[0076] As an optional implementation, the frequency domain function is expressed by the following formula: x=Bw·(1+α)-abs(f);

[0077] Among them, C(k) represents the frequency domain function, a0 represents the weight of a linear function, K1 represents the number of sinusoidal functions of different frequencies, and a i represents the weight of the i-th sine function, b i represents the amplitude of the i-th sine function, K2 represents the number of cosine functions of different frequencies, c i represents the weight of the i-th cosine function, d i represents the amplitude of the i-th cosine function, Bw represents the bandwidth of the OFDM modulation symbol, α represents the roll-off coefficient of the OFDM modulation symbol, f represents the frequency of the OFDM modulation symbol, and abs(*) is the absolute value function.

[0078] As an optional implementation, the b i As i increases, b increases. i is an odd number; and / or,

[0079] The d i As i increases, the d i An odd number.

[0080] As an optional implementation manner, determining the coding matrix corresponding to the OFDM signal according to the frequency domain function value corresponding to the OFDM modulation symbol includes:

[0081] Determine the frequency domain function value corresponding to the OFDM modulation symbol as a coding matrix coefficient;

[0082] The coding matrix corresponding to the OFDM signal is determined according to the product value of the coding matrix coefficient corresponding to the OFDM modulation symbol and the phase factor.

[0083] As an optional implementation,

[0084] The phase factor changes in an exponential function as the second preset parameter of the OFDM modulation symbol changes;

[0085] The second preset parameters include a target symbol length and an expansion coefficient, and the target symbol length is used to represent the length of the OFDM modulation symbol after being processed by the coding matrix.

[0086] In a third aspect, an embodiment of the present disclosure provides a method for determining an inverse coding matrix, the method comprising:

[0087] Obtain a coding matrix determined by the method according to any one of the second aspects; perform inversion processing on the coding matrix to determine an inverse coding matrix.

[0088] In a fourth aspect, an embodiment of the present disclosure provides an OFDM signal transmission method, the method comprising:

[0089] Determine a target OFDM signal according to the method as described in any one of the first aspects; and send the target OFDM signal.

[0090] In a fifth aspect, an embodiment of the present disclosure provides an OFDM signal receiving method, the method comprising:

[0091] Receiving a target OFDM signal determined by the method according to any one of the first aspects, wherein the target OFDM signal is obtained by processing using a coding matrix corresponding to the OFDM signal;

[0092] The target OFDM signal is processed according to an inverse coding matrix to obtain an OFDM signal; wherein the inverse coding matrix is ​​obtained by inverting the coding matrix corresponding to the OFDM signal.

[0093] In a sixth aspect, an embodiment of the present disclosure provides an OFDM signal system, including a network device and a terminal:

[0094] A network device, configured to determine a target OFDM signal according to the method according to any one of the first aspects, and send the target OFDM signal to a terminal, wherein the target OFDM signal is obtained by processing using a coding matrix corresponding to the OFDM signal;

[0095] The terminal is configured to process a target OFDM signal according to an inverse coding matrix to obtain an OFDM signal, wherein the inverse coding matrix is ​​obtained by inverting a coding matrix corresponding to the OFDM signal.

[0096] In a seventh aspect, an embodiment of the present disclosure provides a network device, including a processor and a memory, wherein the memory is used to store a program executable by the processor, and the processor is used to read the program in the memory and perform the following steps:

[0097] Determining a frequency of an OFDM modulation symbol, wherein the OFDM modulation symbol is obtained by digitally modulating an OFDM signal;

[0098] Determining a frequency domain function value corresponding to the frequency of the OFDM modulation symbol based on the frequency domain function and the frequency of the OFDM modulation symbol, wherein the frequency domain function is obtained by linearly combining a linear function and trigonometric functions of different frequencies;

[0099] Determining a coding matrix corresponding to the OFDM signal according to a frequency domain function value corresponding to the OFDM modulation symbol;

[0100] The OFDM signal is processed using a coding matrix corresponding to the OFDM signal to obtain a target OFDM signal that conforms to the variation law of the frequency domain function.

[0101] As an optional implementation, the processor is specifically configured to execute:

[0102] Determining a starting frequency, a frequency step value, and an ending frequency of the OFDM modulation symbol according to the bandwidth of the OFDM modulation symbol and a first preset parameter;

[0103] The frequency of the OFDM modulation symbol is determined according to the starting frequency, the frequency step value and the ending frequency.

[0104] As an optional implementation manner, the first preset parameter includes a roll-off factor, a target symbol length, and a first parameter, where the target symbol length is used to represent the length of the OFDM modulation symbol after being processed by the coding matrix; and the processor is specifically configured to execute:

[0105] Determining a start frequency and an end frequency according to a bandwidth, a roll-off factor, and a target symbol length of the OFDM modulation symbol;

[0106] A frequency step value is determined according to the bandwidth, roll-off factor and first parameter of the OFDM modulation symbol.

[0107] As an optional implementation, the processor is specifically configured to execute:

[0108] Determining a first threshold and a second threshold according to the bandwidth and the roll-off factor of the OFDM modulation symbol;

[0109] When the absolute value of the frequency of the OFDM modulation symbol is greater than a first threshold and less than a second threshold, a frequency domain function value corresponding to the frequency of the OFDM modulation symbol is determined based on the frequency domain function and the frequency of the OFDM modulation symbol.

[0110] As an optional implementation manner, the processor is specifically configured to determine the frequency domain function in the following manner:

[0111] According to the respective weights of the linear function and the trigonometric functions of different frequencies, a weighted sum is performed on the linear function and the trigonometric functions of different frequencies to obtain the frequency domain function.

[0112] As an optional implementation manner, the slope of the linear function changes with changes in the bandwidth and roll-off coefficient of the OFDM signal.

[0113] As an optional implementation manner, the processor is specifically configured to determine the linear function in the following manner:

[0114] Determining a slope according to a bandwidth and a roll-off factor of the OFDM modulation symbol, wherein the slope decreases as the bandwidth and the roll-off factor increase;

[0115] Determining linear function variables according to the bandwidth, roll-off factor, and frequency of the OFDM modulation symbol;

[0116] The first-order linear function is determined according to the slope and the linear function variable.

[0117] As an optional implementation,

[0118] The phases of the trigonometric functions of different frequencies vary with the roll-off factor of the OFDM signal; and / or,

[0119] The amplitude of the trigonometric function increases as the number of the trigonometric functions increases.

[0120] As an optional implementation, the processor is specifically configured to determine the trigonometric function in the following manner:

[0121] Determining the phase of the trigonometric function according to the roll-off coefficient of the OFDM signal;

[0122] Determining trigonometric function variables based on the bandwidth, roll-off factor, and frequency of the OFDM modulation symbol;

[0123] The trigonometric function is determined based on the phase and the trigonometric function variable.

[0124] As an optional implementation manner, the processor is specifically configured to express the frequency domain function by the following formula:

[0125] x=Bw·(1+α)-abs(f);

[0126] Among them, C(k) represents the frequency domain function, a0 represents the weight of a linear function, K1 represents the number of sinusoidal functions of different frequencies, and a i represents the weight of the i-th sine function, b i represents the amplitude of the i-th sine function, K2 represents the number of cosine functions of different frequencies, c i represents the weight of the i-th cosine function, d irepresents the amplitude of the i-th cosine function, Bw represents the bandwidth of the OFDM modulation symbol, α represents the roll-off coefficient of the OFDM modulation symbol, f represents the frequency of the OFDM modulation symbol, and abs(*) is the absolute value function.

[0127] As an optional implementation, the b i As i increases, b increases. i is an odd number; and / or,

[0128] The d i As i increases, the d i An odd number.

[0129] As an optional implementation manner, the processor is specifically configured to:

[0130] Determine the frequency domain function value corresponding to the OFDM modulation symbol as a coding matrix coefficient;

[0131] The coding matrix corresponding to the OFDM signal is determined according to the product value of the coding matrix coefficient corresponding to the OFDM modulation symbol and the phase factor.

[0132] As an optional implementation,

[0133] The phase factor changes in an exponential function as the second preset parameter of the OFDM modulation symbol changes;

[0134] The second preset parameters include a target symbol length and an expansion coefficient, and the target symbol length is used to represent the length of the OFDM modulation symbol after being processed by the coding matrix.

[0135] As an optional implementation manner, the processor is specifically configured to:

[0136] The coding matrix corresponding to the OFDM signal is multiplied by the OFDM signal to obtain a target OFDM signal that conforms to the variation law of the frequency domain function.

[0137] In an eighth aspect, an embodiment of the present disclosure further provides an OFDM signal processing device, the device comprising:

[0138] A frequency determination module, configured to determine a frequency of an OFDM modulation symbol, wherein the OFDM modulation symbol is obtained by digitally modulating an OFDM signal;

[0139] a frequency domain function module, configured to determine a frequency domain function value corresponding to the frequency of the OFDM modulation symbol based on a frequency domain function and the frequency of the OFDM modulation symbol, wherein the frequency domain function is obtained by linearly combining a linear function and trigonometric functions of different frequencies;

[0140] A coding matrix module, configured to determine a coding matrix corresponding to the OFDM signal according to a frequency domain function value corresponding to the OFDM modulation symbol;

[0141] The peak-to-average ratio reduction module is used to process the OFDM signal using the coding matrix corresponding to the OFDM signal to obtain a target OFDM signal that conforms to the change law of the frequency domain function.

[0142] As an optional implementation manner, the frequency determination module is specifically configured to:

[0143] Determining a starting frequency, a frequency step value, and an ending frequency of the OFDM modulation symbol according to the bandwidth of the OFDM modulation symbol and a first preset parameter;

[0144] The frequency of the OFDM modulation symbol is determined according to the starting frequency, the frequency step value and the ending frequency.

[0145] As an optional implementation manner, the first preset parameter includes a roll-off factor, a target symbol length, and a first parameter, the target symbol length being used to represent the length of the OFDM modulation symbol after being processed by the coding matrix; the frequency determination module is specifically configured to:

[0146] Determining a start frequency and an end frequency according to a bandwidth, a roll-off factor, and a target symbol length of the OFDM modulation symbol;

[0147] A frequency step value is determined according to the bandwidth, roll-off factor and first parameter of the OFDM modulation symbol.

[0148] As an optional implementation manner, the frequency domain function module is specifically used to:

[0149] Determining a first threshold and a second threshold according to the bandwidth and the roll-off factor of the OFDM modulation symbol;

[0150] When the absolute value of the frequency of the OFDM modulation symbol is greater than a first threshold and less than a second threshold, a frequency domain function value corresponding to the frequency of the OFDM modulation symbol is determined based on the frequency domain function and the frequency of the OFDM modulation symbol.

[0151] As an optional implementation manner, the frequency domain function module specifically determines the frequency domain function in the following manner:

[0152] According to the respective weights of the linear function and the trigonometric functions of different frequencies, a weighted sum is performed on the linear function and the trigonometric functions of different frequencies to obtain the frequency domain function.

[0153] As an optional implementation manner, the slope of the linear function changes with changes in the bandwidth and roll-off coefficient of the OFDM signal.

[0154] As an optional implementation manner, the frequency domain function module specifically determines the linear function in the following manner:

[0155] Determining a slope according to a bandwidth and a roll-off factor of the OFDM modulation symbol, wherein the slope decreases as the bandwidth and the roll-off factor increase;

[0156] Determining linear function variables according to the bandwidth, roll-off factor, and frequency of the OFDM modulation symbol;

[0157] The first-order linear function is determined according to the slope and the linear function variable.

[0158] As an optional implementation,

[0159] The phases of the trigonometric functions of different frequencies vary with the roll-off factor of the OFDM signal; and / or,

[0160] The amplitude of the trigonometric function increases as the number of the trigonometric functions increases.

[0161] As an optional implementation manner, the frequency domain function module specifically determines the trigonometric function in the following manner:

[0162] Determining the phase of the trigonometric function according to the roll-off coefficient of the OFDM signal;

[0163] Determining trigonometric function variables based on the bandwidth, roll-off factor, and frequency of the OFDM modulation symbol;

[0164] The trigonometric function is determined based on the phase and the trigonometric function variable.

[0165] As an optional implementation manner, the frequency domain function module is specifically configured to express the frequency domain function by the following formula: x=Bw·(1+α)-abs(f);

[0166] Among them, C(k) represents the frequency domain function, a0 represents the weight of a linear function, K1 represents the number of sinusoidal functions of different frequencies, and a i represents the weight of the i-th sine function, b i represents the amplitude of the i-th sine function, K2 represents the number of cosine functions of different frequencies, c i represents the weight of the i-th cosine function, d irepresents the amplitude of the i-th cosine function, Bw represents the bandwidth of the OFDM modulation symbol, α represents the roll-off coefficient of the OFDM modulation symbol, f represents the frequency of the OFDM modulation symbol, and abs(*) is the absolute value function.

[0167] As an optional implementation, the b i As i increases, b increases. i is an odd number; and / or,

[0168] The d i As i increases, the d i An odd number.

[0169] As an optional implementation, the encoding matrix module is specifically configured to:

[0170] Determine the frequency domain function value corresponding to the OFDM modulation symbol as a coding matrix coefficient;

[0171] The coding matrix corresponding to the OFDM signal is determined according to the product value of the coding matrix coefficient corresponding to the OFDM modulation symbol and the phase factor.

[0172] As an optional implementation,

[0173] The phase factor changes in an exponential function as the second preset parameter of the OFDM modulation symbol changes;

[0174] The second preset parameters include a target symbol length and an expansion coefficient, and the target symbol length is used to represent the length of the OFDM modulation symbol after being processed by the coding matrix.

[0175] As an optional implementation, the peak-to-average power ratio reduction module is specifically used to:

[0176] The coding matrix corresponding to the OFDM signal is multiplied by the OFDM signal to obtain a target OFDM signal that conforms to the variation law of the frequency domain function.

[0177] In a ninth aspect, an embodiment of the present disclosure further provides a computer storage medium on which a computer program is stored, which, when executed by a processor, is used to implement the steps of the method described in the first aspect above.

[0178] In a tenth aspect, the present disclosure provides a computer program product, comprising: a computer program code, which, when executed on a computer, enables the computer to execute the method described in any one of the first aspects.

[0179] These and other aspects of the present disclosure will become more readily apparent from the following description of the embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0180] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0181] FIG1 is a flowchart of an implementation method of an OFDM signal processing method provided by an embodiment of the present disclosure;

[0182] FIG2A-FIG2B are flowcharts of determining a coding matrix according to an embodiment of the present disclosure;

[0183] FIG3 is a schematic diagram of a process for solving an inverse coding matrix provided by an embodiment of the present disclosure;

[0184] 4A-4B are flowcharts of a specific implementation of an OFDM signal processing method provided by an embodiment of the present disclosure;

[0185] FIG5 is a schematic diagram showing a CCDF performance comparison between an original OFDM signal and an OFDM signal processed by a coding matrix according to an embodiment of the present disclosure;

[0186] FIG6 is a flowchart of a method for determining a coding matrix according to an embodiment of the present disclosure;

[0187] FIG7 is a flowchart of an implementation method for determining an inverse coding matrix provided by an embodiment of the present disclosure;

[0188] FIG8 is a flowchart of an implementation method for transmitting an OFDM signal provided by an embodiment of the present disclosure;

[0189] FIG9 is a flowchart of an implementation method for receiving an OFDM signal provided by an embodiment of the present disclosure;

[0190] FIG10 is a schematic diagram of an OFDM signal system provided by an embodiment of the present disclosure;

[0191] FIG11 is a schematic diagram of a network device provided by an embodiment of the present disclosure;

[0192] FIG12 is a schematic diagram of a terminal provided in an embodiment of the present disclosure;

[0193] FIG13 is a schematic diagram of an OFDM signal processing device provided by an embodiment of the present disclosure. DETAILED DESCRIPTION

[0194] To make the objectives, technical solutions, and advantages of the present disclosure more clear, the present disclosure will be further described in detail below with reference to the accompanying drawings. It is apparent that the embodiments described are only a portion of the embodiments of the present disclosure, rather than all of them. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present disclosure without creative effort are intended to fall within the scope of protection of the present disclosure.

[0195] In the embodiments of the present disclosure, the term "and / or" describes the association relationship between associated objects, indicating that three possible relationships exist. For example, A and / or B can represent three situations: A exists alone, A and B exist simultaneously, and B exists alone. The character " / " generally indicates that the associated objects are in an "or" relationship.

[0196] The application scenarios described in the embodiments of the present disclosure are intended to more clearly illustrate the technical solutions of the embodiments of the present disclosure and do not constitute a limitation on the technical solutions provided by the embodiments of the present disclosure. Persons skilled in the art will appreciate that, as new application scenarios emerge, the technical solutions provided by the embodiments of the present disclosure will also be applicable to similar technical problems. In the description of the present disclosure, unless otherwise specified, "multiple" means two or more.

[0197] Before introducing the OFDM signal processing method provided by the embodiment of the present disclosure, for ease of understanding, the technical background of the embodiment of the present disclosure is first introduced in detail below.

[0198] Orthogonal Frequency Division Multiplexing (OFDM) is a multi-carrier modulation technology that divides a carrier into several mutually orthogonal subcarriers to overcome frequency-selective fading and narrowband interference. Therefore, as the communication signal of 5G NR (5G New Radio, a global 5G standard based on a new air interface design of OFDM), OFDM has more options for time slots, subcarriers, etc. that can be included in each subframe, so that it can not only support different communication scenarios, but also effectively support different perception scenarios. However, in the OFDM system, the superposition of subcarriers will cause the peak power of the signal to be much greater than its average power, that is, a high PAPR (Peak to Average Power Ratio). Due to power limitations in some scenarios, the high PAPR causes out-of-band radiation and in-band distortion in nonlinear transmission channels, resulting in signal distortion, increasing the system bit error rate, and reducing the performance of the OFDM communication system.

[0199] Methods for suppressing the peak-to-average ratio (PAPR) of OFDM systems primarily include pre-distortion, coding, and probabilistic methods. Pre-distortion methods, such as limiting and companding, primarily reduce the PAPR by performing nonlinear transformations on the signal before it enters the power amplifier, bringing its peak within the amplifier's linear dynamic range. Coding methods utilize different codes to generate different code groups, ultimately selecting the code group with the lowest PAPR for symbol transmission. Probabilistic methods, such as linear transformation (LT), selective mapping (SLM), partial transmission sequence (PTS), and iteratively flipping the partial transmission sequence (IPTS), reduce the probability of large peaks by performing other signal processing. The technologies for reducing the peak-to-average ratio of OFDM signals include the limiting method. Although the technology is simple, it introduces limiting noise, which increases the system bit error rate and reduces system performance. The coding technologies include the block coding method, which does not distort the signal, but the calculation is more complex and generates more redundant data. The probabilistic technologies mainly include the selective mapping method SLM and the partial transmission sequence PTS. Among them, the SLM technology and the PTS technology are simple and intuitive, but the calculation is large and the sideband information needs to be transmitted, which increases the difficulty and cost of system implementation.

[0200] The present disclosure provides a method for OFDM signal processing, which utilizes the basic idea of ​​a probabilistic method to construct a frequency domain function by linearly combining a linear function and trigonometric functions of different frequencies, constructs a coding matrix using the frequency domain function values ​​corresponding to the frequencies of OFDM modulation symbols, and processes the entire OFDM signal using the coding matrix, so that the processed target OFDM signal conforms to the variation pattern of the frequency domain function. Since the frequency domain function constructed by the present disclosure is composed of a linear combination of a linear function and trigonometric functions of different frequencies, and the linear combination of the linear function and trigonometric functions of different frequencies can make the variation pattern of the OFDM signal spectrum meet the requirements of low PAPR, therefore, by implementing a simple probabilistic method that does not require the transmission of sideband information, the PAPR of OFDM can be effectively reduced, thereby improving not only the communication performance of the OFDM system but also the perception performance.

[0201] The present disclosure provides an OFDM signal processing method. The core concept is to design a PAPR-reducing coding matrix, construct a frequency domain function by linearly combining a frequency-related linear function and trigonometric functions of different frequencies, determine the frequency domain function value of each OFDM modulation symbol based on the constructed frequency domain function, and construct a coding matrix based on the frequency domain function value, thereby processing the OFDM signal using the PAPR-reducing coding matrix. The PAPR-reducing coding matrix is ​​simple to implement and does not require the transmission of sideband information. It can effectively reduce the PAPR of broadband OFDM, thereby improving not only the communication performance of the OFDM system but also the perception performance.

[0202] As shown in Figure 1, an embodiment of the present disclosure provides an OFDM signal processing method that can be applied to network devices, such as gNBs, macro base stations, micro base stations, CUs (centralized units), or DUs (distributed units) in 5G. The specific implementation process of the method is as follows:

[0203] Step 100: Determine the frequency of an OFDM modulation symbol, where the OFDM modulation symbol is obtained by digitally modulating an OFDM signal.

[0204] In the implementation, an OFDM signal is received and digitally modulated, such as QPSK (Quadrature Phase Shift Keying), to obtain the corresponding OFDM modulation symbol. At the same time, the total length S of the OFDM modulation symbol and the total transmission time T of the OFDM modulation symbol are obtained. Then, the transmission time of each OFDM modulation symbol is The bandwidth of OFDM modulation symbols is

[0205] Optionally, a first preset parameter may also be set, the first preset parameter including a roll-off coefficient α, a target symbol length N and a first parameter M, wherein the target symbol length is used to represent the length of the OFDM modulation symbol after being processed by the coding matrix.

[0206] Optionally, a second preset parameter may also be set, where the second preset parameter includes a target symbol length N and an expansion coefficient L.

[0207] In some embodiments, the present embodiment determines the frequency of the OFDM modulation symbol by:

[0208] According to the bandwidth of the OFDM modulation symbol and the first preset parameter, the starting frequency, frequency step value and ending frequency of the OFDM modulation symbol are determined; according to the starting frequency, frequency step value and ending frequency, the frequency of the OFDM modulation symbol is determined.

[0209] In some embodiments, the first preset parameters include a roll-off factor, a target symbol length, and a first parameter; the starting frequency and the ending frequency are determined based on the bandwidth, roll-off factor, and target symbol length of the OFDM modulation symbol; and the frequency step value is determined based on the bandwidth, roll-off factor, and the first parameter of the OFDM modulation symbol.

[0210] Optionally, the starting frequency is determined by the following formula:

[0211] In formula (1), f begin represents the starting frequency, Bw represents the bandwidth of the OFDM modulation symbol, α represents the roll-off factor of the OFDM modulation symbol, and N represents the target symbol length.

[0212] The stop frequency is determined by the following formula:

[0213] In formula (2), f finish represents the stop frequency, Bw represents the bandwidth of the OFDM modulation symbol, α represents the roll-off factor of the OFDM modulation symbol, and N represents the target symbol length.

[0214] The frequency step value is determined by the following formula:

[0215] In formula (3), Δf represents the frequency step value, Bw represents the bandwidth of the OFDM modulation symbol, α represents the roll-off coefficient of the OFDM modulation symbol, and M represents the first parameter, such as M=64.

[0216] Step 101: Determine a frequency domain function value corresponding to the frequency of the OFDM modulation symbol based on a frequency domain function and the frequency of the OFDM modulation symbol, wherein the frequency domain function is obtained by linearly combining a linear function and trigonometric functions of different frequencies.

[0217] Optionally, the trigonometric functions of different frequencies in this embodiment include but are not limited to: sine functions of different frequencies, or cosine functions of different frequencies, or a combination of sine functions of different frequencies and cosine functions of different frequencies.

[0218] Optionally, the trigonometric functions of different frequencies include but are not limited to trigonometric functions of different harmonics, which is not specifically limited in this embodiment.

[0219] In some embodiments, the relationship between the frequency of the OFDM modulation symbol and the first threshold and the second threshold may be determined first, and the frequency domain function value may be determined according to different determination results. The specific determination process is as follows:

[0220] Determining a first threshold and a second threshold according to the bandwidth and the roll-off factor of the OFDM modulation symbol;

[0221] When the absolute value of the frequency of the OFDM modulation symbol is greater than a first threshold and less than a second threshold, a frequency domain function value corresponding to the frequency of the OFDM modulation symbol is determined based on the frequency domain function and the frequency of the OFDM modulation symbol.

[0222] In implementation, the first threshold value T1 and the second threshold value T2 are determined by the following formula: T1 = Bw*(1-α); T2 = Bw*(1+α); Formula (4);

[0223] In formula (4), Bw represents the bandwidth of the OFDM modulation symbol, α represents the roll-off coefficient of the OFDM modulation symbol, T1 represents the first threshold, and T2 represents the second threshold.

[0224] Optionally, when the absolute value of the frequency of the OFDM modulation symbol is less than or equal to a first threshold, determining that the frequency domain function value corresponding to the frequency of the OFDM modulation symbol is 1; or,

[0225] When the absolute value of the frequency of the OFDM modulation symbol is greater than or equal to a second threshold, it is determined that the frequency domain function value corresponding to the frequency of the OFDM modulation symbol is 0.

[0226] In implementation, let the frequency domain function be C(k), then if abs(f)≤Bw*(1-α), then C(k)=1;

[0227] If abs(f) ≥ Bw*(1+α), then C(k) = 0. Here, abs(f) represents the absolute value of the frequency of the OFDM modulation symbol, Bw represents the bandwidth of the OFDM modulation symbol, α represents the roll-off factor of the OFDM modulation symbol, and abs(*) is the absolute value function.

[0228] In some embodiments, the frequency domain function is determined as follows:

[0229] According to the respective weights of the linear function and the sine functions of different frequencies, a weighted sum is performed on the linear function and the sine functions of different frequencies to obtain the frequency domain function.

[0230] In some embodiments, the slope of the linear function varies with the bandwidth and roll-off factor of the OFDM signal.

[0231] In some embodiments, the linear function is determined as follows:

[0232] Determining a slope according to a bandwidth and a roll-off factor of the OFDM modulation symbol, wherein the slope decreases as the bandwidth and the roll-off factor increase;

[0233] Determining linear function variables according to the bandwidth, roll-off factor, and frequency of the OFDM modulation symbol;

[0234] The first-order linear function is determined according to the slope and the linear function variable.

[0235] In practice, a linear function can be expressed as the following formula:

[0236] In formula (5), C1(k) represents a linear function, a0 represents the weight of the linear function, Bw represents the bandwidth of the OFDM modulation symbol, α represents the roll-off coefficient of the OFDM modulation symbol, f represents the frequency of the OFDM modulation symbol, and abs(*) is an absolute value function.

[0237] In some embodiments, the phases of the trigonometric functions at different frequencies vary as a roll-off factor of the OFDM signal varies.

[0238] In some embodiments, the amplitude of the trigonometric function increases as the number of the trigonometric functions increases. Optionally, when the trigonometric functions of different frequencies include sine functions of different frequencies, the amplitude of the sine function increases as the number of the sine functions increases; when the trigonometric functions of different frequencies include cosine functions of different frequencies, the amplitude of the cosine function increases as the number of the cosine functions increases; when the trigonometric functions of different frequencies include a combination of sine functions of different frequencies and cosine functions of different frequencies, the amplitude of the sine function increases as the number of the sine functions increases, and the amplitude of the cosine function increases as the number of the cosine functions increases.

[0239] In some embodiments, the trigonometric function is determined as follows:

[0240] Determining the phase of the trigonometric function according to the roll-off coefficient of the OFDM signal;

[0241] Determining trigonometric function variables based on the bandwidth, roll-off factor, and frequency of the OFDM modulation symbol;

[0242] The trigonometric function is determined based on the phase and the trigonometric function variable.

[0243] In practice, trigonometric functions of different frequencies can be expressed by the following formula:

[0244] In formula (6), C2(k) represents trigonometric functions of different frequencies, K1 represents the number of sinusoidal functions of different frequencies, and a i represents the weight of the i-th sine function, b i represents the amplitude of the i-th sine function, K2 represents the number of cosine functions of different frequencies, ci represents the weight of the i-th cosine function, d i represents the amplitude of the i-th cosine function, Bw represents the bandwidth of the OFDM modulation symbol, α represents the roll-off coefficient of the OFDM modulation symbol, f represents the frequency of the OFDM modulation symbol, and abs(*) is the absolute value function. i ≥0, c i ≥0.

[0245] In some embodiments, the frequency domain function is expressed by the following formula:

[0246] Among them, C(k) represents the frequency domain function, a0 represents the weight of a linear function, K1 represents the number of sinusoidal functions of different frequencies, and a i represents the weight of the i-th sine function, b i represents the amplitude of the i-th sine function, K2 represents the number of cosine functions of different frequencies, c i represents the weight of the i-th cosine function, d i represents the amplitude of the i-th cosine function, Bw represents the bandwidth of the OFDM modulation symbol, α represents the roll-off coefficient of the OFDM modulation symbol, f represents the frequency of the OFDM modulation symbol, and abs(*) is the absolute value function.

[0247] In some embodiments, the b i As i increases, b increases. i is an odd number. For example, b i The values ​​are as follows: b1=1, b2=3, b3=5, and so on. i An integer or a decimal.

[0248] In some embodiments, the d i As i increases, the d i is an odd number. For example, d i The values ​​are as follows: d1 = 1, d2 = 3, d3 = 5, and so on. i An integer or a decimal.

[0249] Step 102: Determine a coding matrix corresponding to the OFDM signal according to a frequency domain function value corresponding to the OFDM modulation symbol;

[0250] In some embodiments, the encoding matrix is ​​determined as follows:

[0251] Determine the frequency domain function value corresponding to the OFDM modulation symbol as a coding matrix coefficient;

[0252] The coding matrix corresponding to the OFDM signal is determined according to the product value of the coding matrix coefficient corresponding to the OFDM modulation symbol and the phase factor.

[0253] In some embodiments, the phase factor changes exponentially with the change of a second preset parameter of the OFDM modulation symbol; the second preset parameter includes a target symbol length and an expansion coefficient, and the target symbol length is used to represent the length of the OFDM modulation symbol after being processed by the coding matrix.

[0254] Optionally, the phase factor is expressed as follows:

[0255] In formula (8), pha represents the phase factor, n=1,2,…,N;m=1,2,…,N+2L-1,that is, m represents an integer between 1 and N+2L-1; N represents the target symbol length, L represents the expansion coefficient; exp(*) is the exponential function; □ is the matrix corresponding numerical multiplication operator.

[0256] In implementation, the encoding matrix is ​​expressed by the following formula:

[0257] In formula (9), P(n,m) represents the coding matrix, C(k) represents the frequency domain function corresponding to the OFDM modulation symbol, n=1,2,…,N;m=1,2,…,N+2L-1,that is, m represents an integer between 1 and N+2L-1; N represents the target symbol length, L represents the expansion coefficient; exp(*) is the exponential function; □ is the matrix corresponding numerical multiplication operator.

[0258] Step 103: Process the OFDM signal using the coding matrix corresponding to the OFDM signal to obtain a target OFDM signal that conforms to the frequency domain function variation rule.

[0259] In some embodiments, the OFDM signal is processed using a coding matrix in the following manner:

[0260] The coding matrix corresponding to the OFDM signal is multiplied by the OFDM signal to obtain a target OFDM signal that conforms to the variation law of the frequency domain function.

[0261] As shown in FIG. 2A and FIG. 2B , this embodiment further provides a process for determining a coding matrix, and the specific implementation steps are as follows:

[0262] Step 200: Initialization settings;

[0263] Set the length of the input OFDM modulation symbol to S, the time of all OFDM modulation symbols to T, and the time of each OFDM modulation symbol to The bandwidth of all OFDM modulation symbols is The roll-off coefficient is α, the expansion coefficient is L, and the length of the input OFDM modulation symbol after being processed by the coding matrix for reducing PAPR is N.

[0264] Step 201: Determine the starting frequency f of the OFDM modulation symbol begin , frequency step value Δf and end frequency f finish ;

[0265] Among them, the starting frequency f begin , frequency step value Δf and end frequency f finish The expressions are:

[0266] f begin represents the starting frequency, Bw represents the bandwidth of the OFDM modulation symbol, α represents the roll-off factor of the OFDM modulation symbol, and N represents the target symbol length.

[0267] f finish represents the stop frequency, Bw represents the bandwidth of the OFDM modulation symbol, α represents the roll-off factor of the OFDM modulation symbol, and N represents the target symbol length.

[0268] Δf represents a frequency step value, Bw represents a bandwidth of an OFDM modulation symbol, α represents a roll-off coefficient of an OFDM modulation symbol, and M represents a first parameter, such as M=64.

[0269] Step 202: Set the OFDM modulation symbol counter k=1 and the frequency f=f begin ;

[0270] Among them, starting from the first OFDM modulation symbol, the starting frequency is used as the frequency of the first OFDM modulation symbol, and the frequency domain function value corresponding to the frequency of each OFDM is calculated through the following steps until the end of the last OFDM modulation symbol, and the ending frequency is used as the frequency of the last OFDM modulation symbol.

[0271] Step 203: If the absolute value of the frequency of the OFDM modulation symbol is less than or equal to the first threshold, the frequency domain function value corresponding to the frequency of the OFDM modulation symbol is 1;

[0272] In implementation, the first threshold T1 = Bw*(1-α); if abs(f)≤Bw*(1-α), then the frequency domain function C(k) = 1; abs(f) represents the absolute value of the frequency of the OFDM modulation symbol, Bw represents the bandwidth of the OFDM modulation symbol, and α represents the roll-off coefficient of the OFDM modulation symbol.

[0273] Step 204: If the absolute value of the frequency of the OFDM modulation symbol is greater than the first threshold and less than the second threshold, determine a corresponding frequency domain function value based on the frequency domain function and the frequency;

[0274] Optionally, this embodiment provides an example of a frequency domain function, as shown below:

[0275] If Bw*(1-α)<abs(f)<Bw*(1+α), the frequency domain function C(k) is expressed as follows:

[0276] Where x = Bw (1 + α) - abs(f); a0 represents the linear function combination coefficient, a1 represents the fundamental sinusoidal function combination coefficient, a2 represents the third harmonic sinusoidal function combination coefficient, and a2 represents the fifth harmonic sinusoidal function combination coefficient. abs(f) represents the absolute value of the OFDM modulation symbol frequency, Bw represents the bandwidth of the OFDM modulation symbol, and α represents the roll-off factor of the OFDM modulation symbol.

[0277] Step 205: If the absolute value of the frequency of the OFDM modulation symbol is greater than or equal to the second threshold, the frequency domain function value corresponding to the frequency of the OFDM modulation symbol is 0;

[0278] In implementation, if abs(f)>Bw*(1+α), then the frequency domain function C(k)=0; wherein abs(f) represents the absolute value of the frequency of the OFDM modulation symbol, Bw represents the bandwidth of the OFDM modulation symbol, and α represents the roll-off coefficient of the OFDM modulation symbol.

[0279] Step 206: Determine the counter If yes, execute step S207; otherwise, k=k+1, f=f+Δf, execute step S203;

[0280] Step 207: Use the frequency domain function value as the coding matrix coefficient, and multiply the coding matrix coefficient by the phase factor to obtain the coding matrix.

[0281] Among them, the coding matrix P for reducing PAPR is formed based on the frequency domain function C(k) multiplied by the phase factor. The calculation expression of P is as follows:

[0282] in, n=1,2,…,N;m=1,2,…,N+2L-1;N represents the target symbol length, L represents the expansion coefficient; exp(*) represents the exponential function; □ represents the matrix corresponding numerical multiplication operator.

[0283] In some embodiments, the present disclosure further provides a process for processing the target OFDM signal after receiving the target OFDM signal, which is specifically as follows:

[0284] Performing an inverse processing on the coding matrix corresponding to the OFDM signal to obtain an inverse coding matrix;

[0285] The target OFDM signal is processed using the inverse coding matrix to obtain the OFDM signal.

[0286] In implementation, if the transmitting end reduces the PAPR of the OFDM signal through the coding matrix of this embodiment, the receiving end needs to restore the original OFDM signal through the inverse coding matrix of the coding matrix. As shown in FIG3 , this embodiment provides a process for solving the inverse coding matrix. The inverse coding matrix can be obtained through the following steps:

[0287] Step 300: Perform singular value SVD matrix decomposition on the encoding matrix P to obtain a singular value matrix;

[0288] Among them, the calculation expression of the singular value SVD matrix decomposition is: [A, B, D] = svd(P); svd(*) represents the singular value SVD matrix decomposition function; B represents the singular value; A represents the left singular vector; D represents the right singular vector.

[0289] Step 301: Obtain a diagonal matrix Q based on the singular value matrix B;

[0290] The calculation expression of the diagonal matrix Q is: Q = diag(B); diag(*) is the function for generating the diagonal matrix;

[0291] Step 302: perform a reciprocal operation on the diagonal matrix Q.

[0292] The calculation expression of the reciprocal operation is: Q = 1. / Q;

[0293] Step 303: Calculate the inverse coding matrix P based on the left singular vector A, the right singular vector D and the diagonal matrix Q. -1 ;

[0294] Among them, the inverse coding matrix P -1 The calculation expression is: P -1 =(D□Q')·A'; (*)' is a matrix transposition operator.

[0295] Optionally, the OFDM signals provided by the embodiments of the present disclosure include but are not limited to signals obtained by performing OFDM processing on signals such as PDSCH (Physical Downlink Shared Channel), PDCCH (Physical Downlink Control Channel), and PBCH (Physical Broadcast Channel).

[0296] The OFDM signal processing method provided by this disclosure can be applied to any wireless communication system using OFDM technology. As shown in Figures 4A-4B, the OFDM signal processing method is applied to the 5G NR downlink as an example. The specific implementation process of the OFDM signal processing method is as follows:

[0297] Step 400: On the 5G NR base station side, the downlink signal is digitally modulated to obtain an OFDM signal x_data.

[0298] In practice, the downlink PDSCH / PDCCH / PBCH undergoes cyclic redundancy check (CRC), code block segmentation, channel coding, rate matching, scrambling, symbol modulation, and DMRS (Demodulation Reference Signal) symbol processing to form the signal x_data (i.e., OFDM signal).

[0299] Step 401: The OFDM signal x_data is processed by a coding matrix to obtain a first signal s_data;

[0300] The coding calculation expression is as follows: s_data=x_data*P; P represents the coding matrix of this embodiment.

[0301] Step 402: The first signal s_data is processed and transmitted from the antenna to the terminal;

[0302] In implementation, the first signal s_data is processed by IFFT (Inverse Fast Fourier Transform), CP (Cyclic Prefix) and DAC (Digital to Analog Converter), and then RF processed before being transmitted from the antenna.

[0303] Step 403: At the terminal, the first intermediate signal s_data received from the antenna is processed to obtain a second signal r_data;

[0304] In implementation, the first signal s_data received from the antenna is processed by radio frequency, ADC (Analog-to-Digital Converter), pre-compensation for frequency offset, CP removal, FFT (Fast Fourier Transform), timing synchronization detection, and frequency synchronization to form the second signal r_data;

[0305] Step 404: The second signal r_data is processed by inverse matrix decoding of this embodiment to obtain a third signal r1_data;

[0306] The decoding calculation expression is as follows: r1_data=r_data*P -1 ;P -1 represents the inverse encoding matrix.

[0307] Step 405: The third signal r1_data is subjected to correlation processing to obtain an original OFDM signal.

[0308] During implementation, the third signal r1_data is processed through phase compensation, soft demodulation, descrambling, rate matching, decoding, code block concatenation, and CRC to form PDSCH / PDCCH / PBCH data information.

[0309] As shown in FIG5 , this embodiment provides a CCDF (Complementary Cumulative Distribution Function) performance comparison diagram of an original OFDM signal and an OFDM signal obtained by coding matrix processing. The original OFDM signal adopts QPSK modulation, the subcarrier spacing is 120 kHz, and the OFDM signal has 256 subcarriers. The method for determining the coding matrix in this embodiment is applied to practice. As can be seen from the figure, the coding matrix in this embodiment has a significant improvement on the PAPR performance of the OFDM signal. When the CCDF is 10 -3 When , the coding matrix in this embodiment improves the PAPR suppression capability by 4 dB compared with the original OFDM signal.

[0310] The PAPR-reducing coding matrix design provided in this embodiment uses a linear combination of a linear frequency function and trigonometric functions at different frequencies to construct a frequency domain function. Based on this constructed frequency domain function, a frequency domain function is generated using the starting and cutoff frequencies of the wideband OFDM signal, as well as the frequency step value. Finally, the different frequency domain function values ​​are multiplied by a phase factor to form the PAPR-reducing coding matrix. The PAPR-reducing inverse coding matrix is ​​obtained by performing singular value SVD matrix decomposition on the PAPR-reducing coding matrix, then processing the singular value matrix to obtain a diagonal matrix and performing reciprocal operations to obtain the PAPR-reducing inverse coding matrix. This method can reduce complexity and computational complexity.

[0311] The PAPR reduction coding matrix of this embodiment is applied to a wideband OFDM communication system. The transmitting end (e.g., a base station) uses the PAPR reduction coding matrix to reduce the OFDM signal's PAPR, while the receiving end (e.g., a terminal) uses the inverse PAPR reduction coding matrix to restore the original signal. This PAPR reduction coding matrix is ​​simple to implement and does not require the transmission of sideband information. It can effectively reduce the PAPR of wideband OFDM, thereby improving both OFDM communication performance and perception performance.

[0312] In this embodiment, the method for processing OFDM signals through a coding matrix is ​​to directly multiply the OFDM signal by the coding matrix to obtain the target OFDM signal; the method for obtaining the OFDM signal is to directly multiply the target OFDM signal by the inverse coding matrix to obtain the OFDM signal. This method for processing OFDM signals through the coding matrix is ​​simple and easy to implement, and can be effectively applied to broadband OFDM communication systems to reduce costs.

[0313] Based on the same inventive concept, an embodiment of the present disclosure also provides a method for determining a coding matrix. The principle of solving the problem by the method for determining a coding matrix is ​​similar to that of the OFDM signal processing method. Therefore, the implementation of the network device can refer to the implementation of the method, and the repeated parts will not be repeated.

[0314] As shown in FIG6 , the specific implementation process of the method for determining the encoding matrix is ​​as follows:

[0315] Step 600: Determine the frequency of an OFDM modulation symbol, where the OFDM modulation symbol is obtained by digitally modulating an OFDM signal.

[0316] Step 601: Determine a frequency domain function value corresponding to the frequency of the OFDM modulation symbol based on a frequency domain function and the frequency of the OFDM modulation symbol, wherein the frequency domain function is obtained by linearly combining a linear function and trigonometric functions of different frequencies.

[0317] Step 602: Determine a coding matrix corresponding to the OFDM signal according to a frequency domain function value corresponding to the OFDM modulation symbol.

[0318] As an optional implementation manner, determining the frequency of the OFDM modulation symbol includes:

[0319] Determining a starting frequency, a frequency step value, and an ending frequency of the OFDM modulation symbol according to the bandwidth of the OFDM modulation symbol and a first preset parameter;

[0320] The frequency of the OFDM modulation symbol is determined according to the starting frequency, the frequency step value and the ending frequency.

[0321] As an optional implementation manner, the first preset parameter includes a roll-off factor, a target symbol length, and a first parameter, where the target symbol length is used to represent the length of the OFDM modulation symbol after being processed by the coding matrix;

[0322] Determining a start frequency, a frequency step value, and an end frequency of the OFDM modulation symbol according to the bandwidth of the OFDM modulation symbol and a first preset parameter includes:

[0323] Determining a start frequency and an end frequency according to a bandwidth, a roll-off factor, and a target symbol length of the OFDM modulation symbol;

[0324] A frequency step value is determined according to the bandwidth, roll-off factor and first parameter of the OFDM modulation symbol.

[0325] As an optional implementation manner, determining the frequency domain function value corresponding to the frequency of the OFDM modulation symbol based on the frequency domain function and the frequency of the OFDM modulation symbol includes:

[0326] Determining a first threshold and a second threshold according to the bandwidth and the roll-off factor of the OFDM modulation symbol;

[0327] When the absolute value of the frequency of the OFDM modulation symbol is greater than a first threshold and less than a second threshold, a frequency domain function value corresponding to the frequency of the OFDM modulation symbol is determined based on the frequency domain function and the frequency of the OFDM modulation symbol.

[0328] As an optional implementation manner, the frequency domain function is determined in the following manner:

[0329] According to the respective weights of the linear function and the trigonometric functions of different frequencies, a weighted sum is performed on the linear function and the trigonometric functions of different frequencies to obtain the frequency domain function.

[0330] As an optional implementation manner, the slope of the linear function changes with changes in the bandwidth and roll-off coefficient of the OFDM signal.

[0331] As an optional implementation, the linear function is determined in the following manner:

[0332] Determining a slope according to a bandwidth and a roll-off factor of the OFDM modulation symbol, wherein the slope decreases as the bandwidth and the roll-off factor increase;

[0333] Determining linear function variables according to the bandwidth, roll-off factor, and frequency of the OFDM modulation symbol;

[0334] The first-order linear function is determined according to the slope and the linear function variable.

[0335] As an optional implementation,

[0336] The phases of the trigonometric functions of different frequencies vary with the roll-off factor of the OFDM signal; and / or,

[0337] The amplitude of the trigonometric function increases as the number of the trigonometric functions increases.

[0338] As an optional implementation, the trigonometric function is determined as follows:

[0339] Determining the phase of the trigonometric function according to the roll-off coefficient of the OFDM signal;

[0340] Determining trigonometric function variables based on the bandwidth, roll-off factor, and frequency of the OFDM modulation symbol;

[0341] The trigonometric function is determined based on the phase and the trigonometric function variable.

[0342] As an optional implementation, the frequency domain function is expressed by the following formula: x=Bw·(1+α)-abs(f);

[0343] Among them, C(k) represents the frequency domain function, a0 represents the weight of a linear function, K1 represents the number of sinusoidal functions of different frequencies, and a i represents the weight of the i-th sine function, b i represents the amplitude of the i-th sine function, K2 represents the number of cosine functions of different frequencies, c i represents the weight of the i-th cosine function, d i represents the amplitude of the i-th cosine function, Bw represents the bandwidth of the OFDM modulation symbol, α represents the roll-off coefficient of the OFDM modulation symbol, f represents the frequency of the OFDM modulation symbol, and abs(*) is the absolute value function.

[0344] As an optional implementation, the b i As i increases, b increases.i is an odd number; and / or,

[0345] The d i As i increases, the d i An odd number.

[0346] As an optional implementation manner, determining the coding matrix corresponding to the OFDM signal according to the frequency domain function value corresponding to the OFDM modulation symbol includes:

[0347] Determine the frequency domain function value corresponding to the OFDM modulation symbol as a coding matrix coefficient;

[0348] The coding matrix corresponding to the OFDM signal is determined according to the product value of the coding matrix coefficient corresponding to the OFDM modulation symbol and the phase factor.

[0349] As an optional implementation,

[0350] The phase factor changes in an exponential function as the second preset parameter of the OFDM modulation symbol changes;

[0351] The second preset parameters include a target symbol length and an expansion coefficient, and the target symbol length is used to represent the length of the OFDM modulation symbol after being processed by the coding matrix.

[0352] Based on the same inventive concept, the embodiment of the present disclosure further provides a method for determining an inverse coding matrix, as shown in FIG7 . The specific implementation process of the method is as follows:

[0353] Step 700: Obtain a coding matrix;

[0354] The encoding matrix is ​​determined by the following steps:

[0355] Determining a frequency of an OFDM modulation symbol, wherein the OFDM modulation symbol is obtained by digitally modulating an OFDM signal;

[0356] Determining a frequency domain function value corresponding to the frequency of the OFDM modulation symbol based on the frequency domain function and the frequency of the OFDM modulation symbol, wherein the frequency domain function is obtained by linearly combining a linear function and trigonometric functions of different frequencies;

[0357] A coding matrix corresponding to the OFDM signal is determined according to a frequency domain function value corresponding to the OFDM modulation symbol.

[0358] Step 701: Perform inversion processing on the encoding matrix to determine an inverse encoding matrix.

[0359] Based on the same inventive concept, the embodiment of the present disclosure further provides an OFDM signal transmission method, as shown in FIG8 . The specific implementation process of the method is as follows:

[0360] Step 800: Determine the frequency of an OFDM modulation symbol, where the OFDM modulation symbol is obtained by digitally modulating an OFDM signal.

[0361] Step 801: Determine a frequency domain function value corresponding to the frequency of the OFDM modulation symbol based on a frequency domain function and the frequency of the OFDM modulation symbol, wherein the frequency domain function is obtained by linearly combining a linear function and trigonometric functions of different frequencies.

[0362] Step 802: Determine a coding matrix corresponding to the OFDM signal according to a frequency domain function value corresponding to the OFDM modulation symbol;

[0363] Step 803: Process the OFDM signal using the coding matrix corresponding to the OFDM signal to obtain a target OFDM signal that conforms to the frequency domain function variation rule;

[0364] Step 804: Send the target OFDM signal.

[0365] Based on the same inventive concept, the embodiment of the present disclosure further provides an OFDM signal receiving method, as shown in FIG9 . The specific implementation process of the method is as follows:

[0366] Step 900: Receive a target OFDM signal, where the target OFDM signal is obtained by processing using a coding matrix corresponding to the OFDM signal;

[0367] Step 901: Process the target OFDM signal according to an inverse coding matrix to obtain an OFDM signal; wherein the inverse coding matrix is ​​obtained by inverting the coding matrix corresponding to the OFDM signal.

[0368] Based on the same inventive concept, an embodiment of the present disclosure further provides an OFDM signal system, as shown in FIG10 , including a transmitting device 1000 and a receiving device 1001:

[0369] Transmitting device 1000 is configured to determine a frequency of an OFDM modulation symbol, where the OFDM modulation symbol is obtained by digitally modulating an OFDM signal; determine a frequency domain function value corresponding to the frequency of the OFDM modulation symbol based on a frequency domain function and the frequency of the OFDM modulation symbol, where the frequency domain function is obtained by linearly combining a linear function and trigonometric functions of different frequencies; determine a coding matrix corresponding to the OFDM signal based on the frequency domain function value corresponding to the OFDM modulation symbol; process the OFDM signal using the coding matrix corresponding to the OFDM signal to obtain a target OFDM signal that conforms to a variation pattern of the frequency domain function, and transmit the target OFDM signal;

[0370] The receiving device 1001 is used to receive a target OFDM signal and process the target OFDM signal according to an inverse coding matrix to obtain an OFDM signal, wherein the inverse coding matrix is ​​obtained by inverting the coding matrix corresponding to the OFDM signal.

[0371] It should be noted that the devices in the present disclosure include but are not limited to sending devices and receiving devices. Optionally, the sending device includes a network device and the receiving device includes a terminal. Alternatively, the sending device includes a terminal and the receiving device includes a network device.

[0372] Based on the same inventive concept, the embodiment of the present disclosure also provides a network device. Since the network device is the network device in the method in the embodiment of the present disclosure, and the principle of solving the problem by the network device is similar to that of the method, the implementation of the network device can refer to the implementation of the method, and the repeated parts will not be repeated.

[0373] As shown in FIG11 , the network device includes a processor 1100 and a memory 1101. The memory 1101 is used to store a program executable by the processor 1100. The processor 1100 is used to read the program in the memory 1101 and perform the following steps:

[0374] Determining a frequency of an OFDM modulation symbol, wherein the OFDM modulation symbol is obtained by digitally modulating an OFDM signal;

[0375] Determining a frequency domain function value corresponding to the frequency of the OFDM modulation symbol based on the frequency domain function and the frequency of the OFDM modulation symbol, wherein the frequency domain function is obtained by linearly combining a linear function and trigonometric functions of different frequencies;

[0376] Determining a coding matrix corresponding to the OFDM signal according to a frequency domain function value corresponding to the OFDM modulation symbol;

[0377] The OFDM signal is processed using a coding matrix corresponding to the OFDM signal to obtain a target OFDM signal that conforms to the variation law of the frequency domain function.

[0378] As an optional implementation manner, the processor 1100 is specifically configured to execute:

[0379] Determining a starting frequency, a frequency step value, and an ending frequency of the OFDM modulation symbol according to the bandwidth of the OFDM modulation symbol and a first preset parameter;

[0380] The frequency of the OFDM modulation symbol is determined according to the starting frequency, the frequency step value and the ending frequency.

[0381] As an optional implementation manner, the first preset parameter includes a roll-off factor, a target symbol length, and a first parameter, where the target symbol length is used to represent the length of the OFDM modulation symbol after being processed by the coding matrix; the processor 1100 is specifically configured to execute:

[0382] Determining a start frequency and an end frequency according to a bandwidth, a roll-off factor, and a target symbol length of the OFDM modulation symbol;

[0383] A frequency step value is determined according to the bandwidth, roll-off factor and first parameter of the OFDM modulation symbol.

[0384] As an optional implementation manner, the processor 1100 is specifically configured to execute:

[0385] Determining a first threshold and a second threshold according to the bandwidth and the roll-off factor of the OFDM modulation symbol;

[0386] When the absolute value of the frequency of the OFDM modulation symbol is greater than a first threshold and less than a second threshold, a frequency domain function value corresponding to the frequency of the OFDM modulation symbol is determined based on the frequency domain function and the frequency of the OFDM modulation symbol.

[0387] As an optional implementation manner, the processor 1100 is specifically configured to determine the frequency domain function in the following manner:

[0388] According to the respective weights of the linear function and the trigonometric functions of different frequencies, a weighted sum is performed on the linear function and the trigonometric functions of different frequencies to obtain the frequency domain function.

[0389] As an optional implementation manner, the slope of the linear function changes with changes in the bandwidth and roll-off coefficient of the OFDM signal.

[0390] As an optional implementation manner, the processor 1100 is specifically configured to determine the linear function in the following manner:

[0391] Determining a slope according to a bandwidth and a roll-off factor of the OFDM modulation symbol, wherein the slope decreases as the bandwidth and the roll-off factor increase;

[0392] Determining linear function variables according to the bandwidth, roll-off factor, and frequency of the OFDM modulation symbol;

[0393] The first-order linear function is determined according to the slope and the linear function variable.

[0394] As an optional implementation,

[0395] The phases of the trigonometric functions of different frequencies vary with the roll-off factor of the OFDM signal; and / or,

[0396] The amplitude of the trigonometric function increases as the number of the trigonometric functions increases.

[0397] As an optional implementation, the processor 1100 is specifically configured to determine the trigonometric function in the following manner:

[0398] Determining the phase of the trigonometric function according to the roll-off coefficient of the OFDM signal;

[0399] Determining trigonometric function variables based on the bandwidth, roll-off factor, and frequency of the OFDM modulation symbol;

[0400] The trigonometric function is determined based on the phase and the trigonometric function variable.

[0401] As an optional implementation manner, the processor 1100 is specifically configured to express the frequency domain function by the following formula: x=Bw·(1+α)-abs(f);

[0402] Among them, C(k) represents the frequency domain function, a0 represents the weight of a linear function, K1 represents the number of sinusoidal functions of different frequencies, and a i represents the weight of the i-th sine function, b i represents the amplitude of the i-th sine function, K2 represents the number of cosine functions of different frequencies, c i represents the weight of the i-th cosine function, d i represents the amplitude of the i-th cosine function, Bw represents the bandwidth of the OFDM modulation symbol, α represents the roll-off coefficient of the OFDM modulation symbol, f represents the frequency of the OFDM modulation symbol, and abs(*) is the absolute value function.

[0403] As an optional implementation, the b i As i increases, b increases. i is an odd number; and / or,

[0404] The d i As i increases, the d i An odd number.

[0405] As an optional implementation manner, the processor 1100 is specifically configured to:

[0406] Determine the frequency domain function value corresponding to the OFDM modulation symbol as a coding matrix coefficient;

[0407] The coding matrix corresponding to the OFDM signal is determined according to the product value of the coding matrix coefficient corresponding to the OFDM modulation symbol and the phase factor.

[0408] As an optional implementation,

[0409] The phase factor changes in an exponential function as the second preset parameter of the OFDM modulation symbol changes;

[0410] The second preset parameters include a target symbol length and an expansion coefficient, and the target symbol length is used to represent the length of the OFDM modulation symbol after being processed by the coding matrix.

[0411] As an optional implementation manner, the processor 1100 is specifically configured to:

[0412] The coding matrix corresponding to the OFDM signal is multiplied by the OFDM signal to obtain a target OFDM signal that conforms to the variation law of the frequency domain function.

[0413] Based on the same inventive concept, an embodiment of the present disclosure further provides a terminal, as shown in FIG12 , which includes a processor 1200 and a memory 1201. The memory 1201 is configured to store a program executable by the processor 1200. The processor 1200 is configured to read the program in the memory 1201 and execute the following steps:

[0414] receiving a target OFDM signal, wherein the target OFDM signal is obtained by processing using a coding matrix corresponding to the OFDM signal;

[0415] The target OFDM signal is processed according to an inverse coding matrix to obtain an OFDM signal; wherein the inverse coding matrix is ​​obtained by inverting the coding matrix corresponding to the OFDM signal.

[0416] Based on the same inventive concept, the embodiment of the present disclosure also provides an OFDM signal processing device. Since the device is the device in the method in the embodiment of the present disclosure, and the principle of solving the problem by the device is similar to that of the method, the implementation of the device can refer to the implementation of the method, and the repeated parts will not be repeated.

[0417] As shown in FIG13 , the device includes:

[0418] A frequency determination module 1300 is configured to determine a frequency of an OFDM modulation symbol, where the OFDM modulation symbol is obtained by digitally modulating an OFDM signal;

[0419] A frequency domain function module 1301 is configured to determine a frequency domain function value corresponding to the frequency of the OFDM modulation symbol based on a frequency domain function and the frequency of the OFDM modulation symbol, wherein the frequency domain function is obtained by linearly combining a linear function and trigonometric functions of different frequencies;

[0420] The coding matrix module 1302 is configured to determine a coding matrix corresponding to the OFDM signal according to a frequency domain function value corresponding to the OFDM modulation symbol;

[0421] The peak-to-average ratio reduction module 1303 is configured to process the OFDM signal using a coding matrix corresponding to the OFDM signal to obtain a target OFDM signal that conforms to the variation law of the frequency domain function.

[0422] As an optional implementation manner, the frequency determination module 1300 is specifically configured to:

[0423] Determining a starting frequency, a frequency step value, and an ending frequency of the OFDM modulation symbol according to the bandwidth of the OFDM modulation symbol and a first preset parameter;

[0424] The frequency of the OFDM modulation symbol is determined according to the starting frequency, the frequency step value and the ending frequency.

[0425] As an optional implementation manner, the first preset parameter includes a roll-off factor, a target symbol length, and a first parameter, where the target symbol length is used to represent the length of the OFDM modulation symbol after being processed by the coding matrix; the frequency determination module 1300 is specifically configured to:

[0426] Determining a start frequency and an end frequency according to a bandwidth, a roll-off factor, and a target symbol length of the OFDM modulation symbol;

[0427] A frequency step value is determined according to the bandwidth, roll-off factor and first parameter of the OFDM modulation symbol.

[0428] As an optional implementation manner, the frequency domain function module 1301 is specifically configured to:

[0429] Determining a first threshold and a second threshold according to the bandwidth and the roll-off factor of the OFDM modulation symbol;

[0430] When the absolute value of the frequency of the OFDM modulation symbol is greater than a first threshold and less than a second threshold, a frequency domain function value corresponding to the frequency of the OFDM modulation symbol is determined based on the frequency domain function and the frequency of the OFDM modulation symbol.

[0431] As an optional implementation manner, the frequency domain function module 1301 specifically determines the frequency domain function in the following manner:

[0432] According to the respective weights of the linear function and the trigonometric functions of different frequencies, a weighted sum is performed on the linear function and the trigonometric functions of different frequencies to obtain the frequency domain function.

[0433] As an optional implementation manner, the slope of the linear function changes with changes in the bandwidth and roll-off coefficient of the OFDM signal.

[0434] As an optional implementation manner, the frequency domain function module 1301 specifically determines the linear function in the following manner:

[0435] Determining a slope according to a bandwidth and a roll-off factor of the OFDM modulation symbol, wherein the slope decreases as the bandwidth and the roll-off factor increase;

[0436] Determining linear function variables according to the bandwidth, roll-off factor, and frequency of the OFDM modulation symbol;

[0437] The first-order linear function is determined according to the slope and the linear function variable.

[0438] As an optional implementation,

[0439] The phases of the trigonometric functions of different frequencies vary with the roll-off factor of the OFDM signal; and / or,

[0440] The amplitude of the trigonometric function increases as the number of the trigonometric functions increases.

[0441] As an optional implementation manner, the frequency domain function module 1301 specifically determines the trigonometric function in the following manner:

[0442] Determining the phase of the trigonometric function according to the roll-off coefficient of the OFDM signal;

[0443] Determining trigonometric function variables based on the bandwidth, roll-off factor, and frequency of the OFDM modulation symbol;

[0444] The trigonometric function is determined based on the phase and the trigonometric function variable.

[0445] As an optional implementation manner, the frequency domain function module 1301 is specifically configured to express the frequency domain function by the following formula: x=Bw·(1+α)-abs(f);

[0446] Among them, C(k) represents the frequency domain function, a0 represents the weight of a linear function, K1 represents the number of sinusoidal functions of different frequencies, and a i represents the weight of the i-th sine function, b i represents the amplitude of the i-th sine function, K2 represents the number of cosine functions of different frequencies, c i represents the weight of the i-th cosine function, d i represents the amplitude of the i-th cosine function, Bw represents the bandwidth of the OFDM modulation symbol, α represents the roll-off coefficient of the OFDM modulation symbol, f represents the frequency of the OFDM modulation symbol, and abs(*) is the absolute value function.

[0447] As an optional implementation, the b i As i increases, b increases. i is an odd number; and / or,

[0448] The d i As i increases, the d i An odd number.

[0449] As an optional implementation, the encoding matrix module 1302 is specifically configured to:

[0450] Determine the frequency domain function value corresponding to the OFDM modulation symbol as a coding matrix coefficient;

[0451] The coding matrix corresponding to the OFDM signal is determined according to the product value of the coding matrix coefficient corresponding to the OFDM modulation symbol and the phase factor.

[0452] As an optional implementation,

[0453] The phase factor changes in an exponential function as the second preset parameter of the OFDM modulation symbol changes;

[0454] The second preset parameters include a target symbol length and an expansion coefficient, and the target symbol length is used to represent the length of the OFDM modulation symbol after being processed by the coding matrix.

[0455] As an optional implementation, the peak-to-average power ratio reduction module 1303 is specifically configured to:

[0456] The coding matrix corresponding to the OFDM signal is multiplied by the OFDM signal to obtain a target OFDM signal that conforms to the variation law of the frequency domain function.

[0457] Based on the same inventive concept, embodiments of the present disclosure provide a computer storage medium comprising computer program code. When the computer program code is executed on a computer, the computer executes any of the OFDM signal processing methods discussed above. Because the principles underlying the problems solved by the computer storage medium are similar to those of the OFDM signal processing methods, the implementation of the computer storage medium can be referenced to the implementation of the methods, and any repetitions are omitted.

[0458] In a specific implementation process, computer storage media may include: Universal Serial Bus Flash Drive (USB), mobile hard disk, Read-Only Memory (ROM), Random Access Memory (RAM), magnetic disk or optical disk, and other storage media that can store program code.

[0459] Based on the same inventive concept, embodiments of the present disclosure further provide a computer program product, comprising: computer program code, which, when executed on a computer, causes the computer to perform any of the OFDM signal processing methods discussed above. Because the principles underlying the problems solved by the computer program products are similar to those of the OFDM signal processing methods, the implementation of the computer program products can be referenced to the implementation of the methods, and any repetitions will not be repeated.

[0460] The computer program product can employ any combination of one or more readable media. The readable medium can be a readable signal medium or a readable storage medium. The readable storage medium can be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or component, or any combination thereof. More specific examples (non-exhaustive list) of readable storage media include: an electrical connection with one or more wires, a portable disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof.

[0461] Those skilled in the art will appreciate that the embodiments of the present disclosure may be provided as methods, systems, or computer program products. Therefore, the present disclosure may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Furthermore, the present disclosure may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage and optical storage, etc.) containing computer-usable program code.

[0462] The present disclosure is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present disclosure. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart 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 processes in the flowchart and / or one or more boxes in the block diagram.

[0463] 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 manufactured 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.

[0464] 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.

[0465] Obviously, those skilled in the art may make various changes and modifications to the present disclosure without departing from the spirit and scope of the present disclosure. Thus, if these modifications and variations of the present disclosure fall within the scope of the claims of the present disclosure and their equivalents, the present disclosure is intended to include these modifications and variations.

Claims

1. A method for processing OFDM signals, in, The method includes: Determine a frequency of an OFDM modulation symbol, where the OFDM modulation symbol is obtained by digitally modulating an OFDM signal; Determine, based on the frequency domain function and the frequency of the OFDM modulation symbol, a frequency domain function value corresponding to the frequency of the OFDM modulation symbol, wherein the frequency domain function is obtained by linearly combining a linear function and trigonometric functions of different frequencies; Determining a coding matrix corresponding to the OFDM signal according to a frequency domain function value corresponding to the OFDM modulation symbol; The OFDM signal is processed using a coding matrix corresponding to the OFDM signal to obtain a target OFDM signal that conforms to the variation law of the frequency domain function.

2. The method according to claim 1, in, The determining the frequency of the OFDM modulation symbol comprises: Determine the starting frequency, frequency step value and ending frequency of the OFDM modulation symbol according to the bandwidth of the OFDM modulation symbol and the first preset parameter; The frequency of the OFDM modulation symbol is determined according to the starting frequency, the frequency step value and the ending frequency.

3. The method according to claim 2, in, The first preset parameter includes a roll-off factor, a target symbol length and a first parameter, wherein the target symbol length is used to represent the length of the OFDM modulation symbol after being processed by the coding matrix; Determining the starting frequency, the frequency step value, and the ending frequency of the OFDM modulation symbol according to the bandwidth of the OFDM modulation symbol and the first preset parameter, including: Determine a starting frequency and an ending frequency according to a bandwidth, a roll-off factor, and a target symbol length of the OFDM modulation symbol; A frequency step value is determined according to the bandwidth, the roll-off factor and the first parameter of the OFDM modulation symbol.

4. The method according to claim 1, in, The determining, based on the frequency domain function and the frequency of the OFDM modulation symbol, a frequency domain function value corresponding to the frequency of the OFDM modulation symbol comprises: Determining a first threshold and a second threshold according to the bandwidth and the roll-off factor of the OFDM modulation symbol; When the absolute value of the frequency of the OFDM modulation symbol is greater than the first threshold and less than the second threshold, a frequency domain function value corresponding to the frequency of the OFDM modulation symbol is determined based on the frequency domain function and the frequency of the OFDM modulation symbol.

5. The method according to claim 1, in, The frequency domain function is determined as follows: According to the respective weights of the linear function and the trigonometric functions of different frequencies, a weighted sum is performed on the linear function and the trigonometric functions of different frequencies to obtain the frequency domain function.

6. The method according to claim 1, in, The slope of the linear function changes with the bandwidth and roll-off factor of the OFDM signal.

7. The method according to claim 1, in, The linear function is determined as follows: Determining a slope according to a bandwidth and a roll-off factor of the OFDM modulation symbol, wherein the slope decreases as the bandwidth and the roll-off factor increase; Determining linear function variables according to the bandwidth, roll-off factor and frequency of the OFDM modulation symbol; The first-order linear function is determined according to the slope and the linear function variable.

8. The method according to claim 1, in, The phase of the trigonometric function of different frequencies changes with the roll-off factor of the OFDM signal; and / or, The amplitude of the trigonometric function increases as the number of the trigonometric functions increases.

9. The method according to claim 1, in, The trigonometric functions are determined as follows: Determining the phase of the trigonometric function according to the roll-off factor of the OFDM signal; Determining trigonometric function variables according to the bandwidth, roll-off factor and frequency of the OFDM modulation symbol; The trigonometric function is determined based on the phase and the trigonometric function variable.

10. The method according to claim 1, in, The frequency domain function is expressed by the following formula: x = Bw·(1+α)-abs(f); Among them, C(k) represents the frequency domain function, a 0 represents the weight of a linear function, K1 represents the number of sinusoidal functions of different frequencies, a i represents the weight of the i-th sine function, b i represents the amplitude of the i-th sine function, K2 represents the number of cosine functions with different frequencies, c i represents the weight of the i-th cosine function, d i represents the amplitude of the i-th cosine function, Bw represents the bandwidth of the OFDM modulation symbol, α represents the roll-off coefficient of the OFDM modulation symbol, f represents the frequency of the OFDM modulation symbol, and abs(*) is the absolute value function.

11. The method according to claim 10, in, The b i As i increases, b increases. i is an odd number; and / or, The d i As i increases, the d i Is an odd number.

12. The method according to claim 1, in, The determining, according to the frequency domain function value corresponding to the OFDM modulation symbol, a coding matrix corresponding to the OFDM signal comprises: Determine the frequency domain function value corresponding to the OFDM modulation symbol as a coding matrix coefficient; The coding matrix corresponding to the OFDM signal is determined according to the product value of the coding matrix coefficient corresponding to the OFDM modulation symbol and the phase factor.

13. The method according to claim 12, in, The phase factor changes in an exponential function as the second preset parameter of the OFDM modulation symbol changes; The second preset parameters include a target symbol length and an expansion factor, and the target symbol length is used to represent the length of the OFDM modulation symbol after being processed by the coding matrix.

14. The method according to claim 1, in, The using the coding matrix corresponding to the OFDM signal to process the OFDM signal to obtain a target OFDM signal that conforms to the frequency domain function variation law includes: The coding matrix corresponding to the OFDM signal is multiplied by the OFDM signal to obtain a target OFDM signal that conforms to the variation law of the frequency domain function.

15. A method for determining a coding matrix, in, The method includes: Determine a frequency of an OFDM modulation symbol, where the OFDM modulation symbol is obtained by digitally modulating an OFDM signal; Determine, based on the frequency domain function and the frequency of the OFDM modulation symbol, a frequency domain function value corresponding to the frequency of the OFDM modulation symbol, wherein the frequency domain function is obtained by linearly combining a linear function and trigonometric functions of different frequencies; The coding matrix corresponding to the OFDM signal is determined according to the frequency domain function value corresponding to the OFDM modulation symbol.

16. A method for determining an inverse coding matrix, in, The method includes: Obtaining a coding matrix determined by the method of claim 15; An inverse process is performed on the encoding matrix to determine an inverse encoding matrix.

17. A method for transmitting an OFDM signal, in, The method includes: Determine the target OFDM signal according to any one of the methods described in claims 1 to 14; The target OFDM signal is transmitted.

18. A method for receiving an OFDM signal, in, The method includes: Receiving a target OFDM signal determined by the method according to any one of claims 1 to 14, wherein the target OFDM signal is obtained by processing using a coding matrix corresponding to the OFDM signal; The target OFDM signal is processed according to an inverse coding matrix to obtain an OFDM signal; wherein the inverse coding matrix is ​​obtained by inverting the coding matrix corresponding to the OFDM signal.

19. An OFDM signal transmission system, in, Including sending equipment and receiving equipment: A sending device, configured to determine a target OFDM signal according to any one of the methods described in claims 1 to 14, and send the target OFDM signal, wherein the target OFDM signal is obtained by processing using a coding matrix corresponding to the OFDM signal; A receiving device is used to receive a target OFDM signal, and process the target OFDM signal according to an inverse coding matrix to obtain an OFDM signal, wherein the inverse coding matrix is ​​obtained by inverting a coding matrix corresponding to the OFDM signal.

20. A device, in, The device comprises a processor and a memory, wherein the memory is used to store a program executable by the processor, and the processor is used to read the program in the memory and execute the steps of any one of the methods of claims 1 to 18.

21. A computer storage medium having a computer program stored thereon, in, When the program is executed by a processor, the steps of the method according to any one of claims 1 to 18 are implemented.

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