A clipping method and device

Abstract

The present invention discloses a clipping method and device, including: first-stage low-rate clipping, using a preset first-stage low-rate clipping threshold and a high-pass filter to perform first-stage clipping on an input signal, and outputting a first-stage clipping signal; designing a shaping filter, generating a multi-phase shaping offset pulse according to the shaping filter coefficient and the first-stage clipping signal; and completing second-stage high-rate clipping by subtracting the multi-phase shaping offset pulse from the first-stage clipping signal. The clipping method of the present invention has a simple structure, can reduce resources, and by generating a multi-phase shaping offset pulse, can significantly improve the error vector amplitude after clipping on the basis of ensuring that the spectrum after clipping does not spread.

Description

Technical Field

[0001] The present invention relates to the field of wireless communication technology, and in particular to a clipping method and device. Background Art

[0002] OFDM is a multi-carrier modulation technology, which is widely used in multipath fading conditions. It has the advantages of high spectrum efficiency and resistance to multipath fading, but also has the disadvantages of being sensitive to phase noise and having a large peak-to-average-power-ratio (PAPR). A high peak-to-average-power-ratio requires the high power amplifier to have a large linear dynamic range, which increases the cost of the high power amplifier and reduces its efficiency; if the peak exceeds its linear dynamic range, it will cause in-band distortion and out-of-band dispersion.

[0003] Reducing the peak-to-average ratio is one of the problems that OFDM systems need to solve. The industry has proposed a variety of PAPR reduction solutions, but the bandwidth processing capabilities of these solutions are limited by system clocks and hardware resources. With the increasing demand for large-bandwidth signals (such as 5G high-frequency, high-speed data transmission systems, etc.), more stringent requirements are placed on clock rates and hardware resources, and the scope of application of traditional PAPR reduction technologies has been limited.

[0004] The clipping algorithm is a commonly used method in the industry to reduce the signal PAPR. The traditional clipping method requires multiple levels of iteration to implement (usually three levels of iteration), such as Figure 1 As shown in the figure, the processing of each level of iteration is exactly the same, and it needs to be interpolated to a high rate for peak search, which generally requires 4 times oversampling for peak search. In the application scenario of 5G with large bandwidth, the traditional method will consume a lot of hardware resources, and the cost will increase accordingly. At the same time, the traditional clipping scheme sacrifices part of the error vector amplitude (EVM) in exchange for the reduction of PAPR. With the popularization of high modulation methods (256QAM, 1024QAM, etc.), the system has put forward more stringent requirements on the EVM index. Summary of the invention

[0005] In view of the problems of large hardware resource consumption, large number of iterations and high computational complexity in the current traditional dynamic clipping scheme, the present invention provides a clipping method and device for reducing the peak-to-average ratio of signals in an OFDM system, which is suitable for large-bandwidth application scenarios such as 5G high-frequency and high-speed data transmission systems. It only requires one low-rate clipping and one high-rate clipping to obtain a considerable peak-to-average ratio suppression gain, which greatly reduces the computational complexity and can improve the error vector amplitude of the clipped signal.

[0006] In a first aspect, a clipping method is provided, comprising:

[0007] First-stage low-rate clipping, performing first-stage clipping on the input signal by using a preset first-stage low-rate clipping threshold and a high-pass filter, and outputting a first-stage clipping signal;

[0008] A shaping filter is designed to generate a multi-phase shaping offset pulse according to the shaping filter coefficient and the first-stage clipping signal; the first-stage clipping signal minus the multi-phase shaping offset pulse completes the second-stage high-rate clipping.

[0009] Wherein, the first-stage low-rate clipping includes:

[0010] Performing amplitude limiting processing on the input signal according to a preset first-level low-rate clipping threshold;

[0011] Extract the in-band signal using a high-pass filter;

[0012] Adjust the in-band signal power by weighting factors;

[0013] The power-adjusted in-band signal is recombined with the input signal, and power alignment is performed on the recombined signal.

[0014] The second-level high-rate clipping includes:

[0015] Perform interpolation filtering on the first-stage clipping signal, with an interpolation multiple of M; calculate the positions n1 and n2 corresponding to the original item and the interpolation item according to the interpolation multiple M

[0016] Calculate the amplitude and phase of the output signal after interpolation filtering;

[0017] Perform M-fold decimation on the output amplitude, and output the decimated amplitude and decimated phase;

[0018] Performing a peak search on the extracted amplitude, obtaining the peak value of the extracted amplitude and the maximum phase value corresponding to the peak value of the extracted amplitude according to a preset second-level high-rate clipping threshold;

[0019] Extract the cancellation amplitude according to the peak value of the extracted amplitude and the preset second-level high-rate clipping threshold TH1, generate multiple cancellation signals; and determine the positions of the multiple cancellation signals, the positions include: the original position n1 and the interpolation position n2

[0020] Generate shaping filter coefficients, and generate multi-phase shaping cancellation pulses according to the cancellation signal and the shaping filter coefficients; the multi-phase shaping cancellation pulse spectrum has a large energy concentrated near the transition zone;

[0021] The high-rate clipping is accomplished by subtracting the polyphase shaping cancellation pulse from the first-stage clipping signal.

[0022] Further, generating shaping filter coefficients includes:

[0023] Designing shaping filter coefficients according to the shaping filter sampling rate and the filter spectrum, wherein the shaping filter sampling rate is determined by the input signal sampling rate and the interpolation multiple;

[0024] The shaping filter comprises: a first shaping filter, the spectrum shape of the filter is consistent with the spectrum of the initial signal;

[0025] The second shaping filter has a larger energy of the filter spectrum concentrated at the edge of the in-band signal;

[0026] A shaping filter coefficient is obtained according to the first shaping filter, the first weight factor, the second shaping filter and the second weight factor.

[0027] Performing multi-phase distribution on the shaping filter coefficients;

[0028] Multiple cancellation signals are multiplied by their respective corresponding filter coefficients and then superimposed to generate multi-phase shaped cancellation pulses;

[0029] Optional,

[0030] Add truncation processing before the limiting processing of low-rate clipping, and perform truncation compensation on the reconstructed signal;

[0031] The first-stage clipping signal is truncated before high-rate clipping, and truncation compensation is performed before the cancellation signal is generated.

[0032] In a second aspect, a clipping device is provided, comprising:

[0033] A first-stage low-rate clipping module, which performs first-stage clipping on the input signal using a preset first-stage low-rate clipping threshold and a high-pass filter, and outputs a first-stage clipping signal;

[0034] The second-stage high-rate clipping module is used to generate a multi-phase shaping offset pulse and perform a second-stage high-rate clipping on the first-stage clipping signal.

[0035] The first-stage low-rate clipping module comprises:

[0036] A limiting processing unit, used for performing limiting processing on the input signal according to a preset first-level low-rate clipping threshold;

[0037] An extraction unit, used for extracting an in-band signal from the signal after the amplitude limiting process;

[0038] An adjustment unit, adjusting the in-band signal power through a weight factor;

[0039] A signal recombining unit, which recombines the power-adjusted in-band signal with the initial input signal;

[0040] The power alignment unit is used to align the power of the recombined signal and output the first-level clipping signal.

[0041] Optionally, the first-stage low-rate clipping module further includes:

[0042] A first truncation processing unit performs truncation processing on an input signal and outputs a truncation processing signal;

[0043] The limiting processing unit is further used to perform limiting processing on the truncated processing signal according to a preset first-level low-rate clipping threshold;

[0044] A first truncation compensation unit performs truncation compensation on the recombined signal and outputs the recombined signal after truncation compensation;

[0045] The power alignment unit is also used to perform power alignment on the recombined signal after truncation compensation and output a first-level clipping signal.

[0046] The second-stage high-rate clipping module comprises:

[0047] An interpolation filter unit performs interpolation filtering on the first-stage clipping signal, with an interpolation multiple of M;

[0048] The first determination unit calculates the positions n1 and n2 corresponding to the original signal item and the interpolation item after the interpolation filtering processing according to the interpolation multiple M.

[0049] A first calculation unit calculates the amplitude and phase of the output signal after interpolation filtering processing;

[0050] The extraction unit performs M-fold extraction processing on the output amplitude and outputs the extracted amplitude and the extracted phase;

[0051] A peak search unit performs a peak search on the extracted amplitude, and obtains the peak value of the extracted amplitude and the maximum phase value corresponding to the peak value of the extracted amplitude according to a preset second-level high-rate clipping threshold;

[0052] The cancellation signal generating unit obtains the extracted cancellation amplitude according to the phase maximum value and the preset second-level high-rate clipping threshold, and generates a plurality of cancellation signals;

[0053] A determination unit, and determining the positions of the plurality of cancellation signals, the positions comprising: an original position n1 and an interpolation position n2;

[0054] A second determining unit determines a shaping filter coefficient according to a shaping filter sampling rate and a filter spectrum; the shaping filter sampling rate is determined by an input signal sampling rate and an interpolation multiple;

[0055] The cancellation pulse generating unit generates a multi-phase shaped cancellation pulse according to the cancellation signal and the shaping filter coefficient; the multi-phase shaped cancellation pulse spectrum has a large energy concentrated near the transition zone;

[0056] The clipping unit subtracts the multi-phase shaping offset pulse from the first-stage clipping signal to complete high-rate clipping.

[0057] Furthermore, the second determining unit includes:

[0058] A first determining subunit designs a first shaping filter coefficient according to a shaping filter sampling rate and a filter spectrum, wherein a spectrum shape of the first shaping filter is consistent with an initial signal spectrum;

[0059] A second determining subunit designs a second shaping filter coefficient according to a shaping filter sampling rate and a filter spectrum, wherein the spectrum shape of the second shaping filter has a large energy of the filter spectrum concentrated at an edge of an in-band signal;

[0060] The third determining subunit determines the shaping filter coefficient according to the first shaping filter, the first weight factor, the second shaping filter and the second weight factor.

[0061] The offset pulse generating unit comprises:

[0062] The multi-phase distribution subunit selects the odd and even items of the shaping filter coefficients, and distributes them according to the positions of the plurality of cancellation signals and the odd or even items of the shaping filter coefficients;

[0063] In the calculation subunit, multiple cancellation signals are multiplied by their corresponding filter coefficients and then superimposed to generate multi-phase shaped cancellation pulses:

[0064] Optionally, the second-stage high-rate clipping module further includes:

[0065] A second truncation processing unit performs truncation processing on the first-stage clipping signal and outputs a truncation processing signal;

[0066] The interpolation filtering unit is further used to perform M-fold interpolation filtering on the truncated signal;

[0067] A second truncation compensation unit performs truncation compensation on the offset amplitude and outputs the offset amplitude after truncation compensation;

[0068] The cancellation signal generating unit further generates a cancellation signal by using the cancellation amplitude and the maximum phase value after truncation compensation.

[0069] Beneficial effects achieved by the present invention:

[0070] 1. The first-stage low-rate clipping method proposed in the present invention does not need to be up-interpolated to 2 or 4 times, and has a simple structure, which can reduce resources.

[0071] 2. The second-stage high-rate clipping method proposed in the present invention can significantly improve the EVM performance after clipping by generating multi-phase shaping offset pulses, while ensuring that the spectrum after clipping does not spread;

[0072] 3. The present invention proposes a truncation and clipping solution, which can further reduce resources and improve the performance of the wireless communication system.

[0073] For the above and related purposes, one or more embodiments include features that will be described in detail below and particularly pointed out in the claims. The following description and the accompanying drawings describe certain exemplary aspects in detail, and are indicative of only some of the various ways in which the principles of the various embodiments may be employed. Other benefits and novel features will become apparent as the following detailed description is considered in conjunction with the accompanying drawings, and the disclosed embodiments are intended to include all such aspects and their equivalents. BRIEF DESCRIPTION OF THE DRAWINGS

[0074] Figure 1 It is a structural diagram of a traditional clipping method in the prior art;

[0075] Figure 2 is a flow chart of a clipping method provided by Embodiment 1 of the present invention;

[0076] Figure 2a is a flow chart of a first-stage low-rate clipping method provided in Embodiment 1 of the present invention;

[0077] Figure 2b is a structural diagram of a first-stage low-rate clipping method provided in Embodiment 1 of the present invention;

[0078] Figure 3a is a flow chart of the second-stage high-rate clipping method provided in Embodiment 1 of the present invention;

[0079] Figure 3b is a structural diagram of a second-stage high-rate clipping method provided in Embodiment 1 of the present invention;

[0080] Figure 4a is a spectrum diagram of a first shaping filter provided in Embodiment 1 of the present invention;

[0081] Figure 4b is a spectrum diagram of a second shaping filter provided in Embodiment 1 of the present invention;

[0082] Figure 5a is a flow chart of a first-level low-rate clipping method provided by Embodiment 2 of the present invention;

[0083] Figure 5bis a structural diagram of a first-level low-rate clipping method provided in Embodiment 2 of the present invention;

[0084] Figure 6 is a structural diagram of a second-stage high-rate clipping method provided in Embodiment 2 of the present invention;

[0085] Figure 7a This is a block diagram of the first-stage low-rate clipping module provided in the third embodiment of the present invention;

[0086] Figure 7b This is another block diagram of the first-stage low-rate clipping module provided in the third embodiment of the present invention;

[0087] Figure 8a This is a block diagram of the second-stage high-rate clipping module provided in the third embodiment of the present invention;

[0088] Figure 8b This is another block diagram of the composition of the second-stage high-rate clipping module provided in the third embodiment of the present invention. DETAILED DESCRIPTION

[0089] The following description and the accompanying drawings fully illustrate specific embodiments of the present invention so that those skilled in the art can practice them. Other embodiments may include structural, logical, electrical, process and other changes. The examples represent possible changes only. Unless explicitly required, separate components and functions are optional, and the order of operation may vary. Parts and features of some embodiments may be included in or replace parts and features of other embodiments. The scope of the embodiments of the present invention includes the entire scope of the claims, and all available equivalents of the claims. In this article, these embodiments of the present invention may be represented individually or collectively by the term "invention", which is only for convenience, and if more than one invention is actually disclosed, it is not intended to automatically limit the scope of the application to any single invention or inventive concept. DETAILED DESCRIPTION

[0091] Embodiment 1

[0092] This embodiment provides a clipping method, such as Figure 2 As shown, including:

[0093] S1. The first stage low-rate clipping is performed by using a preset first stage low-rate clipping threshold and a high-pass filter to perform the first stage clipping on the input signal and output the first stage clipping signal;

[0094] Specifically, Figure 2a As shown, including:

[0095] S11. The input signal is limited according to a preset first-level low-rate clipping threshold; further, the limiting process includes:

[0096] S11a. Amplitude calculation, calculating the amplitude Mag of the input signal data_in;

[0097] S11b peak search, preset the first low-rate clipping threshold TH, according to the set threshold value TH, find the amplitude Mag exceeding the TH value, recorded as the peak value Peak;

[0098] According to Formula 1, the clipping factor w is calculated according to the peak value Peak and the first-level low-rate clipping threshold TH:

[0099]

[0100] S11c clips the input signal;

[0101] According to the clipping factor w, the input signal data_in is processed as follows: data_cl=data_in*w, and the limited signal data_cl is obtained;

[0102] It should be noted that, since a certain amount of time is required in steps S11a and S11b, delay alignment is required when proceeding to step S11c; Figure 2b This is the first-level low-rate clipping method structure diagram; through the structure Figure 2b The delay unit 1 in the embodiment realizes the time alignment of the input signal data_in and the peak value Peak.

[0103] S12. Extracting the in-band signal using a high-pass filter;

[0104] The limited signal data_cl is filtered by a high pass filter (HPF) to obtain an out-of-band signal data_ob. Then, the in-band signal data_ib is extracted by subtracting the filtered out-of-band signal data_ob from the limited signal data_cl, as shown in the following formula 2:

[0105]

[0106] Where conv represents the convolution operation, and hbf_coef represents the high-pass filter HPF coefficient;

[0107] Since there is a delay in the filtering process, when calculating data_ib, it is necessary to ensure that data_cl and data_ob are aligned in time. This process is done by Figure 2b The delay unit 2 in is completed.

[0108] S13. Adjust the in-band signal power by weight factor;

[0109] The weight factor WF is set to adjust the power of the in-band signal data_ib, and the power-adjusted in-band signal data_pow_adj is obtained according to Formula 3;

[0110] data_pow_adj=data_ib*WF formula 3

[0111] S14. Recombine the power-adjusted in-band signal data_pow_adj with the initial input signal:

[0112] Add data_pow_adj to the initial input signal data_in to complete the signal reorganization:

[0113] data_low_rate=data_in+data_pow_adj formula 4

[0114] Since steps S11-S13 take a certain amount of time to implement, when performing step S14, it is necessary to perform delay alignment to ensure that data_in and the recombined signal data_pow_adj are aligned in time. This process is performed by Figure 2b The delay unit 3 in is completed.

[0115] S15. Power aligning the recombined signal;

[0116] The power of the reconstructed signal data_low_rate is generally lower than the power of the initial signal, so power alignment is required. The specific processing process is shown in the following formula 5:

[0117]

[0118] When calculating gain, you need to select N samples from data_in and data_low_rate for calculation. Not all samples are needed. According to experience, the maximum value of N is no more than 1000.

[0119] The reconstructed signal data_out1 after power alignment is the first-stage clipping signal;

[0120] Among them, the first-level low-rate clipping threshold TH and weight factor WF are preset according to the clipping performance required by the system, that is, the PAPR, EVM and adjacent channel power leakage ratio ACPR (Adjacent Channel Power Ratio) of the clipped signal. A large amount of traversal work is performed in the simulation in advance to determine, or it is set according to actual experience values. The specific setting method will not be repeated in the embodiment of the present invention.

[0121] S2. Design a shaping filter, generate a multi-phase shaping offset pulse according to the shaping filter coefficient and the first-stage clipping signal; subtract the multi-phase shaping offset pulse from the first-stage clipping signal to complete the second-stage high-speed clipping;

[0122] Specifically, Figure 3a As shown, the following steps are included:

[0123] S21. Perform interpolation filtering on the first-stage clipping signal, with an interpolation multiple of M; calculate the positions n1 and n2 corresponding to the original item and the interpolation item respectively according to the interpolation multiple M;

[0124] Figure 3b It is a structural diagram of the second-stage high-rate clipping method;

[0125] Perform interpolation filtering on data_out1, use a half-band filter as the filter, and output the interpolation filtering signal data_up;

[0126] The interpolation filtering includes two processing processes: interpolation and filtering. The interpolation is M times to insert M-1 zeros between two adjacent points. The filtering is to perform convolution processing on the signal after the interpolation is M times. The convolution processing inserts M-1 zero values ​​between two adjacent points to turn it into a non-zero value, while the values ​​of the two points before and after the value do not change.

[0127] The positions of the original term and the interpolation term are calculated in different ways due to different interpolation multiples. The positions n1 and n2 of the original term and the interpolation term are calculated according to the interpolation multiple M. The interpolation multiple is generally 2 or 4 times.

[0128] Exemplarily, the interpolation multiple M is 2, and the input signal data_out1 = [abc d...], then after being interpolated by 2 times, it becomes data_out1_up = [a 0b 0c 0d 0...], and after filtering, it becomes data_up = [a a1 bb1 c c1 d d1....], where [a1 b1 c1 d1...] is the interpolation item, and the value [ab c d...] that is the same as the input signal data_out1 is the original item;

[0129] At this time, the length of the interpolation filter output signal data_up becomes twice that of the input signal data_out1. The relationship between data_up and data_out1 is shown in Formula 6:

[0130]

[0131] Where n1 is the position of the original item, n2 is the position of the interpolation item, and len is the length of data_up. The positions of the original item and the interpolation item are determined by Formula 6.

[0132] The interpolation multiple M is 4, and the input signal data_out1 = [abc d...], then after interpolation of 4 times, it becomes data_out1_up = [a 0 0 0b 0 0 0c 0 0 0d 0 0 0...], and after filtering, it becomes data_up = [a a11 a21 a31 b b11 b21 b31 c c11 c21 c31 d d11 d21 d31....]; among which [a11 a21a31 b11 b21 b31 c11 c21 c31 d11 d21 d31...] is the interpolation item, and [a bc d...] is the original item;

[0133] At this time, the length of data_up becomes 4 times that of data_out1. The relationship between data_up and data_out1 is shown in Formula 7. The corresponding positions of the original term n1 and the interpolation term n2 are determined by Formula 7:

[0134]

[0135] Where len1 represents the length of data_up, len is the length of data_out1, and satisfies len1=4*len; nn represents each item in data_up; the remaining items in nn except those equal to n1 are interpolation items n2.

[0136] S22. Calculate the amplitude and phase of the output signal data_up after interpolation filtering;

[0137] The amplitude and phase of data_up are calculated. Generally, the Cordic algorithm (Coordinate Rotation Digital Computer) is used to implement this function and output the amplitude mag1 and phase ph1.

[0138] S23. Perform M-fold decimation on the output amplitude mag1, and output the decimated amplitude mag2 and the corresponding decimated phase ph2;

[0139] Specifically, the decimation multiple M is consistent with the interpolation multiple in step S21; the M-fold decimation process is to retain the larger value among the adjacent M mag1 values, and output the decimated amplitude mag2 and the corresponding phase ph2.

[0140] For example, assuming mag1 = [2 3 1 5 7 8 9 10], ph1 = [0.1 0.2 0.3 0.4 0.50.60.7 0.8], if M = 2, the output after 2x decimation is mag2 = [3 5 8 10], ph2 = [0.2 0.40.60.8]; if M = 4, the output after 4x decimation is mag2 = [5 10], ph2 = [0.4 0.8].

[0141] S24. Perform a peak search on the extracted amplitude mag2, and obtain the peak value mag3 of the extracted amplitude according to the preset second-level high-rate clipping threshold; obtain the maximum phase value ph3 corresponding to the extracted amplitude;

[0142] 1) Perform a three-point peak search on mag2 to find the maximum value mag2 among the three adjacent mag2 values max , and retain the phase ph2 corresponding to the maximum value max , the rest of the values ​​are set to 0;

[0143] 2) Mag2 retained after three-point peak search max Compare with the preset second highest rate clipping threshold TH1, and retain the mag2 greater than TH1 max And its corresponding phase ph2 max ; The rest are less than mag2 of TH1 max And the corresponding ph2 max Then set it to 0; as shown in Formula 8:

[0144]

[0145] Exemplarily, assume that mag2 = [1 3 2 4 2 3 5 1], ph2 = [0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8], and the second high-rate clipping threshold TH1 = 3 is preset; then after step 1, it becomes mag2 = [0 3 04 0 0 5 0], ph2 = [0 0.2 0 0.4 0 0 0.7 0]; after step 2, it becomes mag3 = [0 00 4 0 0 5 0], ph3 = [00 0 0.4 0 0 0.7 0].

[0146] S25. Extract the offset amplitude can_mag according to mag3 and the preset second-stage high-rate clipping threshold TH1;

[0147] can_mag=mag3-TH1;

[0148] S26. Generate multiple cancellation signals, and determine the positions of the multiple cancellation signals;

[0149] The cancellation amplitude can_mag outputted in step S25 and the phase maximum value ph3 outputted in step S24 are used to generate the cancellation signal can_sig; this process is equivalent to converting the "amplitude and phase" into the "real part and imaginary part of the complex signal", and the Cordic algorithm is generally used to implement this function;

[0150] A plurality of cancellation signals are obtained, and positions of the cancellation signals are respectively matched; the positions include: original position n1 and interpolation position n2, and it is determined whether each cancellation signal is at the original position n1 or the interpolation position n2.

[0151] S27. Generate shaping filter coefficients;

[0152] Designing shaping filter coefficients according to the shaping filter sampling rate and the filter spectrum, wherein the shaping filter sampling rate is determined by the input signal sampling rate and the interpolation multiple;

[0153] Specifically,

[0154] S27a. Design the first shaping filter coefficient filter1 according to the shaping filter sampling rate and the filter spectrum, wherein the first shaping filter sampling rate Fs1 is Fs1 = M * Fs, Fs is the sampling rate of the input signal data_in, and M is the interpolation multiple;

[0155] The spectrum shape of the first shaping filter is consistent with the spectrum of the initial signal; the spectrum of the first shaping filter generated by the design is as follows: Figure 4a As shown, it can be ensured that the spectrum of the clipped signal will not spread.

[0156] S27b according to the shaping filter sampling rate, the filter spectrum design second shaping filter coefficient filter2, wherein the second shaping filter sampling rate Fs1 is Fs1 = M * Fs, Fs is the sampling rate of the input signal data_in, M is the interpolation multiple;

[0157] The spectrum shape of the second shaping filter has a large energy concentration at the edge of the in-band signal, such as Figure 4b As shown, it can be seen that compared with the filter spectrum of filter1, the shape of the filter spectrum of filter2 has changed significantly, that is, there will be a bulge in the edge domain spectrum of the in-band signal. This function can be achieved by a sinc filter. Other methods that can achieve this function are also within the scope of protection of the present invention and are not limited here.

[0158] The second shaping filter can concentrate the greater energy in the filter at the edge of the in-band signal, that is, close to the transition band position, and can concentrate the greater energy of the final generated cancellation pulse close to the transition band position, reducing in-band damage without affecting the EVM of the signal.

[0159] S27c. According to the first shaping filter, the first weight factor, the second shaping filter and the second weight factor, a shaping filter coefficient filter is obtained;

[0160] The first shaping filter can ensure that the spectrum of the clipped signal will not spread, but it will cause greater damage to the signal, that is, the EVM is poor;

[0161] The second shaping filter, if Figure 4b Moving the raised part to the transition zone can significantly improve EVM, but it will increase the cutoff bandwidth of the filter, resulting in the diffusion of the signal spectrum after clipping.

[0162] Therefore, in the present invention, a first shaping filter filter1 is designed, corresponding to a first weight factor w1, and a second shaping filter filter2 is designed, corresponding to a second weight factor w2; by adjusting the values ​​of w1 and w2, the advantages of filter1 and filter2 are concentrated, and the EVM performance after clipping can be significantly improved on the basis of ensuring that the spectrum after clipping does not spread;

[0163] filter=w1*filter1+w2*filter2

[0164] w1+w2=1Formula 9

[0165] Wherein, w1 and w2 are both decimals less than 1; the specific values ​​can be determined according to the clipping performance required by the system, that is, the PAPR and EVM of the clipped signal, or can be set according to actual experience values, and the specific setting method will not be repeated in the embodiment of the present invention;

[0166] It should be noted that Figure 4a and Figure 4b Only half of the spectrum is drawn, which has characterized its spectral characteristics. The other half is symmetrical with it and is not drawn.

[0167] S28. Perform multi-phase distribution on the shaping filter coefficient filter;

[0168] Specifically, they include:

[0169] S28a. Filter out the odd and even items of the shaping filter coefficients filter;

[0170] The odd-numbered items refer to the filter coefficients at odd positions, and the even-numbered items refer to the filter coefficients at even positions, which are screened according to formula 10:

[0171]

[0172] Where len represents the total number of coefficients contained in the filter coefficient hb, hb_odd represents odd items, and hb_even represents even items;

[0173] For example: suppose the filter coefficient hb = [abcde], then its odd term hb_odd = [ace], and its even term hb_even = [bd].

[0174] S28b. Allocate odd-numbered items or even-numbered items of shaping filter coefficients corresponding to the respective cancellation signals according to the respective positions of the plurality of cancellation signals.

[0175] According to the respective positions of the multiple cancellation signals obtained in step S26, they are corresponded and allocated to the odd or even items of the shaping filter coefficient: if the cancellation signal obtained in step S26 is at the position of the original item (i.e., n1), then the corresponding filter coefficient is hb_odd in S28a; if the cancellation signal obtained in step S26 is at the position of the interpolation item (i.e., n2), then the corresponding filter coefficient is hb_even in S28a.

[0176] S29. Generate a multi-phase shaped cancellation pulse according to the cancellation signal and the shaping filter coefficient and perform clipping;

[0177] Multiple cancellation signals can_sig are multiplied by their respective corresponding filter coefficients and then superimposed to generate a multi-phase shaped cancellation pulse can_pulse:

[0178]

[0179] The first-stage clipping signal minus the multi-phase shaping offset pulse completes high-rate clipping;

[0180] The first-stage clipping signal data_out1 is subtracted from the canceling pulse can_pulse to output the second-stage clipping signal data_out, that is, data_out=data_out1-can_pulse, thereby completing the second-stage high-speed clipping process.

[0181] It should be noted that since steps S21-S29 take a certain amount of time to implement, it is necessary to perform delay alignment. Figure 3b The delay unit 4 in ensures that data_out1 and can_pulse are aligned in time.

[0182] Embodiment 2

[0183] The larger the signal bit width is, the larger the bit width of the calculation result will be after operations such as addition and multiplication, which will increase the resource demand. In order to reduce the increase in bit width caused by the calculation process, a bit clipping method is proposed in this implementation, which can further reduce resources.

[0184] This embodiment provides a clipping method, including:

[0185] S4. The first stage low-rate clipping is performed by using a preset first stage low-rate clipping threshold and a high-pass filter to perform the first stage clipping on the input signal, and outputting the first stage clipping signal; Figure 5a As shown, including:

[0186] S41. Perform truncation processing on the input signal data_in according to formula 12, and output the truncation processing signal data_in_cut;

[0187]

[0188] Where round means rounding, and cut_width is the truncation width;

[0189] Preferably, cut_width is generally 2 bits to ensure that clipping does not affect EVM.

[0190] Figure 5b It is the structural diagram of the first-stage low-rate clipping method;

[0191] S42. According to the preset first-level low-rate clipping threshold, the truncated signal data_in_cut is limited, and the limited signal data_cl is output;

[0192] The specific amplitude limiting process is the same as the process method of step S11 in the first embodiment, and will not be described in detail here;

[0193] S43. Extracting the in-band signal using a high-pass filter;

[0194] The limited signal data_cl is filtered by a high-pass filter HPF to obtain an out-band signal data_ob, and then the in-band signal data_ib is extracted by subtracting the filtered out-band signal data_ob from the limited signal data_cl;

[0195] S44. Adjust the in-band signal power by the weight factor;

[0196] The weight factor WF is set to adjust the power of the in-band signal data_ib, and the power-adjusted in-band signal data_pow_adj is obtained according to Formula 3;

[0197] S45. Add data_pow_adj to the initial input signal data_in to complete signal reorganization, and output the reorganized signal data_low_rate;

[0198] S46. Perform truncation compensation on the recombined signal data_low_rate according to formula 13, and output the recombined signal data_low_comp after truncation compensation;

[0199] data_low_comp=round(data_low_rate*2 cut_width ) Formula 13

[0200] S47. Power align the recombined signal data_low_comp after truncation compensation;

[0201] The power of the reconstructed signal data_low_rate is generally lower than the power of the initial signal, so power alignment is required. The specific processing process is shown in Formula 5.

[0202] Since steps S41-S45 take a certain amount of time to implement, when performing step S46, it is necessary to perform delay alignment to ensure that data_in and the reassembled signal data_pow_adj are aligned in time. This process is performed by Figure 5b The delay unit 3 in is completed.

[0203] S5. Design a shaping filter, generate a multi-phase shaping offset pulse according to the shaping filter coefficient and the first-stage clipping signal; subtract the multi-phase shaping offset pulse from the first-stage clipping signal to complete the second-stage high-speed clipping;

[0204] Specifically, Figure 6 As shown, including:

[0205] S51. Perform truncation processing on the first-stage clipping signal data_out1 according to formula 14, and output a truncation processing signal data_in_cut;

[0206]

[0207] Preferably, cut_width is set to 2 bits to ensure that clipping does not affect EVM.

[0208] S52. Perform interpolation filtering on the truncated signal data_in_cut, with an interpolation multiple of M; calculate the positions n1 and n2 corresponding to the original item and the interpolation item respectively according to the interpolation multiple M; and output the interpolation filtering output signal data_up;

[0209] The specific interpolation filtering process is the same as that in step S21 of the first embodiment.

[0210] S53. Calculate the amplitude mag1 and phase ph1 of the output signal data_up after interpolation filtering;

[0211] S54. Perform M-fold decimation on the output amplitude mag1, and output the decimated amplitude mag2 and the corresponding decimated phase ph2;

[0212] S55. Perform a peak search on the extracted amplitude mag2, and obtain the peak value mag3 of the extracted amplitude according to the preset second-level high-rate clipping threshold; obtain the maximum phase value ph3 corresponding to the extracted amplitude;

[0213] S56. Extract the offset amplitude can_mag according to mag3 and the preset second-level high-rate clipping threshold TH1;

[0214] S57. Perform truncation compensation on the cancellation amplitude can_mag according to formula 15, and output the cancellation amplitude can_mag_comp after truncation compensation;

[0215] can_mag_comp=round(can_mag*2 cut_width ) Formula 15

[0216] S58. Generate a cancellation signal can_sig according to the cancellation amplitude can_mag_comp after truncation compensation; and determine the positions of the multiple cancellation signals;

[0217] S59. Generate a multi-phase shaped cancellation pulse can_pulse according to the cancellation signal can_sig and the shaping filter coefficient;

[0218] The shaping filter coefficient generation method and the multi-phase shaping cancellation pulse generation method have been described in detail in steps S27-S29 of the first embodiment and will not be repeated here.

[0219] S6. The first clipping signal minus the multi-phase shaping offset pulse to complete high-rate clipping;

[0220] The first-stage clipping signal data_out1 is subtracted from the canceling pulse can_pulse to output the second-stage clipping signal data_out, that is, data_out=data_out1-can_pulse, thereby completing the second-stage high-speed clipping process.

[0221] It should be noted that since steps S51-S59 take a certain amount of time to implement, it is necessary to perform delay alignment. Figure 6 The delay unit 4 in ensures that data_out1 and can_pulse are aligned in time.

[0222] Embodiment 3

[0223] This embodiment provides a clipping device 300, including:

[0224] A first-stage low-rate clipping module 310 performs first-stage clipping on the input signal using a preset first-stage low-rate clipping threshold and a high-pass filter, and outputs a first-stage clipping signal;

[0225] The second-stage high-rate clipping module 320 is used to generate a multi-phase shaping cancellation pulse and perform a second-stage high-rate clipping on the first-stage clipping signal.

[0226] The first-stage low-rate clipping module 310 is as follows: Figure 7a As shown, including:

[0227] A limiting processing unit 311 is used to perform limiting processing on the input signal according to a preset first-level low-rate clipping threshold;

[0228] Furthermore, the limiting processing unit 311 includes:

[0229] The amplitude calculation subunit 311a is used to calculate the amplitude Mag of the input signal data_in;

[0230] The peak search subunit 311b is used to preset the first-level low-rate clipping threshold TH, and according to the set threshold value TH, find the amplitude Mag exceeding the TH value, which is recorded as the peak value Peak;

[0231] The clipping subunit 311c clips the input signal data_in according to the clipping factor w, and outputs a limited signal data_cl;

[0232] The first delay subunit 311d is used to achieve time alignment between the input signal data_in and the peak value Peak.

[0233] The extraction unit 312 is used to extract the in-band signal data_ib of the limiting signal data_cl; comprising:

[0234] The high-pass filter 312a is used to filter the limited signal data_cl to obtain an out-of-band signal data_ob;

[0235] The first calculation subunit 312b is configured to subtract the out-band signal data_ob obtained by filtering from the limited signal data_cl to obtain an in-band signal data_ib.

[0236] The second delay unit 312c is used to achieve delay alignment between data_cl and data_ob.

[0237] An adjustment unit 313 adjusts the in-band signal power by a weight factor;

[0238] The power of the in-band signal data_ib is adjusted by a preset weight factor WF, and the power-adjusted in-band signal data_pow_adj is obtained according to Formula 3;

[0239] The signal reorganization unit 314 adds data_pow_adj to the initial input signal data_in to complete signal reorganization;

[0240] The third delay unit 314a is used to achieve delay alignment between the input signal data_in and the reorganized signal data_pow_adj;

[0241] A power alignment unit 315 is used to perform power alignment on the recombined signal according to Formula 5 to output a first-stage clipping signal data_out1;

[0242] Optionally, the first stage low rate clipping module 310, such as Figure 7b As shown, it also includes:

[0243] The first truncation processing unit 316 performs truncation processing on the input signal data_in according to formula 12, and outputs a truncation processing signal data_in_cut;

[0244] The limiting processing unit 311 is further used to perform limiting processing on the truncated signal data_in_cut according to a preset first-level low-rate clipping threshold, and output a limited signal data_cl;

[0245] The first truncation compensation unit 317 performs truncation compensation on the recombined signal data_low_rate according to formula 13, and outputs a recombined signal data_low_comp after truncation compensation;

[0246] The power alignment unit 315 is further used to perform power alignment on the recombined signal data_low_comp after truncation compensation according to Formula 5, and output the first-stage clipping signal data_out1.

[0247] The second stage high rate clipping module 320, such as Figure 8a As shown, including:

[0248] The interpolation filter unit 321 performs interpolation filtering processing on the first-stage clipping signal data_out1, and the interpolation multiple is M; the filter uses a half-band filter, and the interpolation filtering processing outputs the signal data_up;

[0249] The positions of the original term and the interpolation term are calculated in different ways due to different interpolation multiples. The positions n1 and n2 of the original term and the interpolation term are calculated according to the interpolation multiple M. The interpolation multiple is generally 2 or 4 times.

[0250] The first determining unit 322 calculates the positions n1 and n2 corresponding to the original term and the interpolation term of the signal after the interpolation filtering processing according to the interpolation multiple M.

[0251] A first calculation unit 323 calculates the amplitude mag1 and the phase ph1 of the output signal data_up after the interpolation filtering process;

[0252] The decimation unit 324 performs M-fold decimation processing on the output amplitude mag1, and outputs the decimated amplitude mag2 and the corresponding decimated phase ph2; the decimation multiple M is consistent with the interpolation multiple in the interpolation filter unit 321;

[0253] The peak search unit 325 performs peak search on the extracted amplitude mag2, obtains the peak value mag3 of the extracted amplitude according to the preset second-level high-rate clipping threshold, and obtains the phase maximum value ph3 corresponding to the extracted amplitude;

[0254] The cancellation signal generating unit 326 obtains the extracted cancellation amplitude according to the phase maximum value ph3 and the preset second-level high-rate clipping threshold TH1, and generates multiple cancellation signals; specifically, the cancellation signal generating unit 326 includes:

[0255] An extraction unit 326a extracts a cancellation amplitude can_mag according to mag3 and a preset second-level high-rate clipping threshold TH1;

[0256] The second calculation unit 326b generates a cancellation signal can_sig using the cancellation amplitude can_mag and the phase maximum value ph3. The Cordic algorithm is generally used to implement this function.

[0257] The determination unit 327 performs position correspondence on each cancellation signal; the positions include: the original position n1 and the interpolation position n2, and determines whether each cancellation signal is at the original position n1 or the interpolation position n2.

[0258] The second determining unit 328 determines the shaping filter coefficient according to the shaping filter sampling rate and the filter spectrum, specifically including:

[0259] The first determining subunit 328a designs a first shaping filter coefficient filter1 according to the shaping filter sampling rate and the filter spectrum, wherein the first shaping filter sampling rate Fs1 is Fs1=M*Fs, Fs is the sampling rate of the input signal data_in, and M is the interpolation multiple;

[0260] The spectrum shape of the first shaping filter is consistent with the spectrum of the initial signal;

[0261] The second determining subunit 328b designs a second shaping filter coefficient filter2 according to the shaping filter sampling rate and the filter spectrum, wherein the second shaping filter sampling rate Fs1 is Fs1=M*Fs, Fs is the sampling rate of the input signal data_in, and M is the interpolation multiple;

[0262] The spectrum shape of the second shaping filter has a large energy of the filter spectrum concentrated at the edge of the in-band signal;

[0263] The third determining subunit 328c obtains a shaping filter coefficient filter according to the first shaping filter, the first weight factor, the second shaping filter and the second weight factor by using formula 9;

[0264] By adjusting the values ​​of w1 and w2, the EVM performance after clipping can be significantly improved while ensuring that the spectrum after clipping does not spread.

[0265] The cancellation pulse generating unit 329 generates a multi-phase shaped cancellation pulse according to the cancellation signal and the shaping filter coefficient; the multi-phase shaped cancellation pulse spectrum has a large energy concentrated outside the transition band;

[0266] A multi-phase distribution subunit 329a performs multi-phase distribution on the shaping filter coefficient filter;

[0267] Filter out the odd and even items of the shaping filter coefficients filter;

[0268] According to the step determination unit 327, the respective positions of the plurality of cancellation signals are obtained, and the positions are corresponded and allocated to the odd or even items of the shaping filter coefficients;

[0269] The calculation subunit 329b generates a multi-phase shaped cancellation pulse according to the cancellation signal and the shaping filter coefficient; a plurality of cancellation signals can_sig are multiplied by their respective corresponding filter coefficients, and then superimposed to generate a multi-phase shaped cancellation pulse can_pulse:

[0270] Clipping unit 3210, the first-stage clipping signal minus the multi-phase shaping offset pulse to complete high-rate clipping;

[0271] The first-stage clipping signal data_out1 is subtracted from the offset pulse can_pulse to output the second-stage clipping signal data_out, that is, data_out=data_out1-can_pulse, completing the second-stage high-speed clipping process;

[0272] The fourth delay unit 3211 ensures that data_out1 and can_pulse are aligned in time.

[0273] The second stage high rate clipping module 320, such as Figure 8b As shown, it also includes:

[0274] The second truncation processing unit 3212 performs truncation processing on the first-stage clipping signal data_out1 according to formula 14, and outputs a truncation processing signal data_in_cut;

[0275] The interpolation filter unit 321 is further used to perform interpolation filtering on the truncated signal data_in_cut, with an interpolation multiple of M;

[0276] The second truncation compensation unit 3213 performs truncation compensation on the cancellation amplitude can_mag according to formula 15, and outputs the cancellation amplitude can_mag_comp after truncation compensation;

[0277] The cancellation signal generating unit 326 further generates a cancellation signal can_sig by using the cancellation amplitude can_mag_comp after truncation compensation and the phase maximum value ph3.

[0278] It will be appreciated by those skilled in the art that the various exemplary method steps and device units described herein in conjunction with the disclosed embodiments can all be implemented in electronic hardware, software, or a combination of the two. In order to clearly illustrate the interchangeability between hardware and software, the various exemplary steps and units are generally described in the form of their functionality. Whether this functionality is implemented in hardware or software depends on the design constraints implemented by the specific application and the entire system. Those skilled in the art can implement the described functionality in a variety of ways for each specific application, but the results of this implementation should not be interpreted as departing from the scope of the present invention.

[0279] The steps of the method described in conjunction with the above disclosed embodiments may be directly embodied as hardware, a software module executed by a processor, or a combination of the two. The software module may exist in a RAM memory, a flash memory, a ROM memory, an EPROM memory, an EEPROM memory, a register, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. A typical storage medium is coupled to a processor so that the processor can read information from the storage medium and write information to the storage medium. In an alternative embodiment, the storage medium is an integral part of the processor. The processor and the storage medium may exist in an ASIC. The ASIC may exist in a user station. In an alternative embodiment, the processor and the storage medium may exist as discrete components in a user station.

[0280] According to the disclosed embodiments, it is possible for those skilled in the art to implement or use the present invention. It is obvious to those skilled in the art that various modifications of these embodiments are possible, and the general principles defined herein can also be applied to other embodiments without departing from the scope and gist of the present invention. The embodiments described above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A clipping method, characterized in that: include: First-stage low-rate clipping, using a preset first-stage low-rate clipping threshold and a high-pass filter to perform first-stage clipping on the input signal, and output a first-stage clipping signal; Design a shaping filter, generate a multi-phase shaping offset pulse according to the shaping filter coefficient and the first-stage clipping signal; subtract the multi-phase shaping offset pulse from the first-stage clipping signal to complete the second-stage high-rate clipping; The first-stage clipping of the input signal is performed by using a preset first-stage low-rate clipping threshold and a high-pass filter, and the output of the first-stage clipping signal includes: The input signal data_in is truncated and the truncated signal data_in_cut is output. The truncation processing formula is: round means rounding, cut_width means the truncation width; According to the preset first-level low-rate clipping threshold, the truncated signal data_in_cut is limited, and the limited signal data_cl is output; The limited signal data_cl is filtered by a high-pass filter HPF to obtain an out-band signal data_ob, and then the in-band signal data_ib is extracted by subtracting the filtered out-band signal data_ob from the limited signal data_cl; Set a weight factor WF, adjust the power of the in-band signal data_ib, and obtain a power-adjusted in-band signal data_pow_adj; Add data_pow_adj to the initial input signal data_in to complete signal reorganization and output the reorganized signal data_low_rate; The recombined signal data_low_rate is truncation-compensated and the recombined signal data_low_comp after truncation-compensation is output; the truncation-compensation formula is: data_low_comp=round(data_low_rate*2 cut_width ); Power align the reconstructed signal data_low_comp after truncation compensation; The method of generating a multi-phase shaping offset pulse according to the shaping filter coefficient and the first-stage clipping signal and completing the second-stage high-speed clipping by subtracting the multi-phase shaping offset pulse from the first-stage clipping signal includes: The first-stage clipping signal data_out1 is truncated to output a truncated signal data_in_cut. The truncation processing formula is: Perform interpolation filtering on the truncated signal data_in_cut, with an interpolation multiple of M; calculate positions n1 and n2 corresponding to the original item and the interpolation item respectively according to the interpolation multiple M; and output the interpolation filtering output signal data_up; Calculate the amplitude mag1 and phase ph1 of the output signal data_up after interpolation filtering; The output amplitude mag1 is decimated M times, and the decimated amplitude mag2 and the corresponding decimated phase ph2 are output; Perform peak search on the extracted amplitude mag2, and obtain the peak value mag3 of the extracted amplitude according to the preset second-level high-rate clipping threshold; obtain the maximum phase value ph3 corresponding to the extracted amplitude; Extract the offset amplitude can_mag according to the peak value mag3 of the extracted amplitude and the preset second-stage high-rate clipping threshold TH1; Generate a cancellation signal can_sig using the cancellation amplitude can_mag and the phase maximum value ph3; and determine the positions of the multiple cancellation signals; A multi-phase shaped cancellation pulse can_pulse is generated according to the cancellation signal can_sig and the shaping filter coefficient.

2. The clipping method according to claim 1, characterized in that: The second-level high-rate clipping includes: Perform interpolation filtering on the first-stage clipping signal, with an interpolation multiple of M; calculate the positions of the original item and the interpolation item according to the interpolation multiple M; Calculate the amplitude and phase of the output signal after interpolation filtering; Perform M-fold decimation on the output amplitude, and output the decimated amplitude and decimated phase; Performing a peak search on the extracted amplitude, obtaining the peak value of the extracted amplitude and the maximum phase value corresponding to the peak value of the extracted amplitude according to a preset second-level high-rate clipping threshold; Extracting the cancellation amplitude according to the peak value of the extracted amplitude and the preset second-level high-rate clipping threshold to generate multiple cancellation signals; and determining the positions of the multiple cancellation signals, the positions including: the original position n1 and the interpolation position n2; Generate shaping filter coefficients, and generate multi-phase shaping cancellation pulses according to the cancellation signal and the shaping filter coefficients; the multi-phase shaping cancellation pulse spectrum has a large energy concentrated near the transition zone; The first-stage clipping signal minus the multi-phase shaping cancellation pulse completes the second-stage high-rate clipping.

3. The clipping method according to claim 2, characterized in that: The generating shaping filter coefficients comprises: Designing shaping filter coefficients according to the shaping filter sampling rate and the filter spectrum, wherein the shaping filter sampling rate is determined by the input signal sampling rate and the interpolation multiple; The shaping filter comprises: a first shaping filter, the spectrum shape of the filter is consistent with the spectrum of the initial signal; The second shaping filter has a larger energy of the filter spectrum concentrated at the edge of the in-band signal; A shaping filter coefficient is obtained according to the first shaping filter, the first weight factor, the second shaping filter and the second weight factor.

4. The clipping method according to claim 2, characterized in that: Generates multi-phase shaped cancellation pulses including: Performing multi-phase distribution on the shaping filter coefficients; Multiple cancellation signals are multiplied by their respective corresponding filter coefficients and then superimposed to generate multi-phase shaped cancellation pulses.

5. The clipping method according to claim 4, characterized in that: The multi-phase distribution of the shaping filter coefficients comprises: Screen out the odd and even terms of the shaping filter coefficients; The odd-numbered items or even-numbered items of the shaping filter coefficients corresponding to the respective cancellation signals are allocated according to the respective positions of the plurality of cancellation signals.

6. A clipping device, characterized in that: include: A first-stage low-rate clipping module, which performs first-stage clipping on the input signal using a preset first-stage low-rate clipping threshold and a high-pass filter, and outputs a first-stage clipping signal; The second-stage high-rate clipping module is used to generate a multi-phase shaping offset pulse and perform a second-stage high-rate clipping on the first-stage clipping signal; The first-stage clipping of the input signal is performed by using a preset first-stage low-rate clipping threshold and a high-pass filter, and the output of the first-stage clipping signal includes: The input signal data_in is truncated and the truncated signal data_in_cut is output. The truncation processing formula is: round means rounding, cut_width means the truncation width; According to the preset first-level low-rate clipping threshold, the truncated signal data_in_cut is limited, and the limited signal data_cl is output; The limited signal data_cl is filtered by a high-pass filter HPF to obtain an out-band signal data_ob, and then the in-band signal data_ib is extracted by subtracting the filtered out-band signal data_ob from the limited signal data_cl; Set a weight factor WF, adjust the power of the in-band signal data_ib, and obtain a power-adjusted in-band signal data_pow_adj; Add data_pow_adj to the initial input signal data_in to complete signal reorganization and output the reorganized signal data_low_rate; The recombined signal data_low_rate is truncation-compensated and the recombined signal data_low_comp after truncation-compensation is output; the truncation-compensation formula is: data_low_comp=round(data_low_rate*2 cut_width ); Power align the reconstructed signal data_low_comp after truncation compensation; The second-stage high-rate clipping of the first-stage clipping signal includes: The first-stage clipping signal data_out1 is truncated to output a truncated signal data_in_cut. The truncation processing formula is: Perform interpolation filtering on the truncated signal data_in_cut, with an interpolation multiple of M; calculate positions n1 and n2 corresponding to the original item and the interpolation item respectively according to the interpolation multiple M; and output the interpolation filtering output signal data_up; Calculate the amplitude mag1 and phase ph1 of the output signal data_up after interpolation filtering; The output amplitude mag1 is decimated M times, and the decimated amplitude mag2 and the corresponding decimated phase ph2 are output; Perform peak search on the extracted amplitude mag2, and obtain the peak value mag3 of the extracted amplitude according to the preset second-level high-rate clipping threshold; obtain the maximum phase value ph3 corresponding to the extracted amplitude; Extract the offset amplitude can_mag according to the peak value mag3 of the extracted amplitude and the preset second-stage high-rate clipping threshold TH1; Generate a cancellation signal can_sig using the cancellation amplitude can_mag and the phase maximum value ph3; and determine the positions of the multiple cancellation signals; A multi-phase shaped cancellation pulse can_pulse is generated according to the cancellation signal can_sig and the shaping filter coefficient.

7. The clipping device according to claim 6, characterized in that The second-stage high-rate clipping module comprises: An interpolation filter unit performs interpolation filtering on the first-stage clipping signal, with an interpolation multiple of M; A first determining unit calculates positions corresponding to the original term and the interpolation term of the signal after the interpolation filtering process according to the interpolation multiple M; A first calculation unit calculates the amplitude and phase of the output signal after interpolation filtering processing; The extraction unit performs M-fold extraction processing on the output amplitude and outputs the extracted amplitude and the extracted phase; A peak search unit performs a peak search on the extracted amplitude, and obtains the peak value of the extracted amplitude and the maximum phase value corresponding to the peak value of the extracted amplitude according to a preset second-level high-rate clipping threshold; A determination unit, configured to determine positions of the plurality of cancellation signals, wherein the positions include: an original position n1 and an interpolation position n2; A second determining unit determines a shaping filter coefficient according to a shaping filter sampling rate and a filter spectrum; the shaping filter sampling rate is determined by an input signal sampling rate and an interpolation multiple; The cancellation pulse generating unit generates a multi-phase shaped cancellation pulse according to the cancellation signal and the shaping filter coefficient; the multi-phase shaped cancellation pulse spectrum has a large energy concentrated near the transition zone; The clipping unit subtracts the multi-phase shaping offset pulse from the first-stage clipping signal to complete the second-stage high-rate clipping.

8. The clipping device according to claim 7, characterized in that The second determining unit includes: A first determining subunit determines a first shaping filter coefficient according to a shaping filter sampling rate and a filter spectrum, wherein a spectrum shape of the first shaping filter is consistent with an initial signal spectrum; A second determining subunit determines a second shaping filter coefficient according to a shaping filter sampling rate and a filter spectrum, wherein the spectrum shape of the second shaping filter has a large filter spectrum energy concentrated at an edge of an in-band signal; The third determining subunit determines the shaping filter coefficient according to the first shaping filter, the first weight factor, the second shaping filter and the second weight factor.

9. The clipping device according to claim 7, characterized in that The offset pulse generating unit comprises: The multi-phase distribution subunit selects the odd and even items of the shaping filter coefficients, and distributes them according to the positions of the plurality of cancellation signals and the odd or even items of the shaping filter coefficients; In the calculation subunit, multiple cancellation signals are multiplied by their respective corresponding filter coefficients and then superimposed to generate multi-phase shaped cancellation pulses.

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