Crest factor reduction method and device based on peak type

Abstract

The invention relates to a crest factor reduction method and device based on a peak value type, and relates to the technical field of signal processing, and the method comprises the steps: calculating a modulus value of an in-phase orthogonal signal based on an in-phase component and an orthogonal component of the in-phase orthogonal signal; determining a peak value based on the modulus value of the in-phase orthogonal signal and a preset first peak clipping threshold; determining the type of the peak value based on the peak value and the first peak clipping threshold; determining a base pulse based on the type of the peak value; calculating a pulse coefficient based on the first peak clipping threshold, the in-phase orthogonal signal and the modulus value of the in-phase orthogonal signal; calculating a peak clipping pulse based on the basic pulse and the pulse coefficient; subtracting the peak clipping pulse from the in-phase orthogonal signal to obtain a signal after peak cancellation; determining a module value of the signal after peak cancellation; and based on the signal after peak cancellation, the module value of the signal after peak cancellation and a preset second peak clipping threshold, determining a signal after hard peak clipping.

Description

Technical Field

[0001] The present application relates to the field of signal processing technology, and more specifically, to a method and device for reducing a crest factor based on a peak type. Background Art

[0002] In-phase and quadrature signals often have a high peak-to-average power ratio. In order to optimize transmitter performance, crest factor reduction technology is usually used to reduce the peak-to-average power ratio of the signal.

[0003] Existing crest factor reduction methods based on peak cancellation require multiple iterations of the following process: signal modulus calculation, peak detection, pulse generation, and pulse cancellation.

[0004] However, this method requires at least two iterative operations, which consumes a lot of computation. Summary of the Invention

[0005] The present application is provided to solve the above-mentioned problems existing in the prior art. According to an embodiment of the present application, a method and apparatus for reducing a crest factor based on a peak type can avoid executing multiple iterative operations and reduce the amount of calculation.

[0006] In a first aspect, an embodiment of the present application provides a method for reducing a crest factor based on a peak type, comprising:

[0007] Calculating a modulus of the in-phase and quadrature signals based on the in-phase and quadrature components of the in-phase and quadrature signals;

[0008] Determining a peak value based on a modulus value of the in-phase and quadrature signals and a preset first peak clipping threshold;

[0009] determining a type of the peak based on the peak and the first peak clipping threshold;

[0010] Determining a basic pulse based on the type of the peak; wherein different peak types correspond to different basic pulses, and the basic pulse is determined by a filter coefficient design method, and different basic pulses correspond to different filter coefficients;

[0011] Calculating a pulse coefficient based on the first peak clipping threshold, the in-phase and quadrature signals, and the modulus of the in-phase and quadrature signals;

[0012] Calculating a peak clipping pulse based on the basic pulse and the pulse coefficient;

[0013] Subtracting the peak clipping pulse from the in-phase and quadrature signals to obtain a peak-cancelled signal;

[0014] Determining a modulus of the signal after peak cancellation;

[0015] A hard peak-clipped signal is determined based on the peak-canceled signal, the modulus of the peak-canceled signal, and a preset second peak-clipped threshold.

[0016] In a second aspect, an embodiment of the present application provides a crest factor reduction device based on peak cancellation, comprising:

[0017] A peak determination module is configured to calculate a modulus of the in-phase and quadrature signals based on the in-phase and quadrature components of the in-phase and quadrature signals; and determine a peak value based on the modulus of the in-phase and quadrature signals and a preset first peak clipping threshold;

[0018] a peak cancellation module configured to determine a type of the peak based on the peak and the first peak clipping threshold; determine a basic pulse based on the type of the peak, wherein different peak types correspond to different basic pulses, the basic pulses are determined by a filter coefficient design method, and different basic pulses correspond to different filter coefficients; calculate a pulse coefficient based on the first peak clipping threshold, the in-phase orthogonal signal, and the modulus of the in-phase orthogonal signal; calculate a peak clipping pulse based on the basic pulse and the pulse coefficient; and subtract the peak clipping pulse from the in-phase orthogonal signal to obtain a peak-canceled signal;

[0019] The hard peak clipping module is configured to determine the modulus of the peak cancellation signal; and determine the hard peak clipping signal based on the peak cancellation signal, the modulus of the peak cancellation signal and a preset second peak clipping threshold.

[0020] In a third aspect, an embodiment of the present application provides a computer program product, including a computer program / instruction, which, when executed by a processor, implements the method described in any of the above embodiments.

[0021] The beneficial effects of the embodiments of the present application are as follows: different filter coefficients can be used to determine basic pulses of different waveforms. Based on the peak type, a basic pulse that is more compatible with the in-phase orthogonal signal can be selected from different basic pulses. The peak-clipped pulse obtained from this basic pulse has a better single-shot peak-clipping effect, eliminating the need for multiple iterations, reducing the computational complexity and the system latency caused by multiple iterations. Furthermore, combining peak cancellation with hard peak clipping can further improve the peak-clipping effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In the drawings, which are not necessarily drawn to scale, the same reference numerals may describe similar components in different views. The same reference numerals with letter suffixes or different letter suffixes may represent different instances of similar components. The accompanying drawings generally illustrate various embodiments by way of example and not limitation, and together with the description and claims, serve to illustrate the disclosed embodiments. Where appropriate, the same reference numerals are used throughout the drawings to refer to the same or similar parts. Such embodiments are illustrative and are not intended to be exhaustive or exclusive of the embodiments of the present apparatus or method.

[0023] Figure 1 This is a flowchart of a peak factor reduction method based on peak type provided by an embodiment of the present application;

[0024] Figure 2 1 is a schematic diagram of envelope waveforms of different types of peaks provided by an embodiment of the present application;

[0025] Figure 3 This is a schematic diagram of a basic pulse with different types of peaks provided by an embodiment of the present application;

[0026] Figure 4 This is a schematic diagram of a signal envelope waveform before and after peak clipping provided by an embodiment of the present application;

[0027] Figure 5 This is a schematic diagram comparing power spectrum densities of different signals provided by an embodiment of the present application;

[0028] Figure 6 is a complementary cumulative distribution function curve provided by an embodiment of the present application;

[0029] Figure 7 is a schematic diagram of a transmission system provided by an embodiment of the present application;

[0030] Figure 8 This is a schematic diagram of a crest factor reduction device based on peak cancellation provided by an embodiment of the present application. DETAILED DESCRIPTION

[0031] To enable those skilled in the art to better understand the technical solution of the present application, the present application is described in detail below in conjunction with the accompanying drawings and specific embodiments. The embodiments of the present application are further described in detail below in conjunction with the accompanying drawings and specific embodiments, but are not intended to limit the present application. The terms "first," "second," and "third" used in this application are merely intended to distinguish corresponding features, and do not necessarily represent a need for such an order, nor do they necessarily represent only the singular form.

[0032] like Figure 1As shown, the embodiment of the present application provides a method for reducing a crest factor based on a peak type, including:

[0033] Step 101: Calculate the modulus of the in-phase and quadrature signals based on the in-phase and quadrature components of the in-phase and quadrature signals.

[0034] The modulus of the in-phase and quadrature signals can be calculated using formula (1).

[0035]

[0036] Where a(n) represents the modulus of the in-phase and quadrature signals before peak clipping, i(n) represents the in-phase component, and q(n) represents the quadrature component. The in-phase and quadrature signals can be obtained by orthogonal frequency division multiplexing modulation or other modulation methods.

[0037] Step 102: Determine a peak value based on the modulus value of the in-phase and quadrature signals and a preset first peak clipping threshold.

[0038] a(n)>T1 (2)

[0039] a(n)≥a(n-1),a(n)≥a(n+1) (3)

[0040] When the modulus value of the nth point of the in-phase orthogonal signal satisfies equations (2) and (3), the modulus value of the nth point of the in-phase orthogonal signal is the peak value, T1 is used to represent the first peak clipping threshold, a(n-1) is used to represent the modulus value of the preceding signal point adjacent to the signal point corresponding to the peak value, and a(n+1) is used to represent the modulus value of the subsequent signal point adjacent to the signal point corresponding to the peak value. For ease of description, the modulus value of the nth point of the in-phase orthogonal signal is used as an example in the following description.

[0041] Step 103: Determine the type of the peak based on the peak value and the first peak clipping threshold.

[0042] In actual application scenarios, the number of types and the basis for classification are not fixed and can be adjusted according to business needs.

[0043] Step 104: Determine a basic pulse based on the type of peak value; different types of peak values ​​correspond to different basic pulses, and the basic pulse is determined by a filter coefficient design method, and different basic pulses correspond to different filter coefficients.

[0044] The type of peak corresponds to the basic pulse one by one. Different filter coefficients can be obtained by setting the parameters of the filter. The filter coefficients are also called the filter impulse response. The filter coefficients are the basic pulses, and these basic pulses correspond to different peak types.

[0045] Step 105: Calculate the pulse coefficient based on the first peak clipping threshold, the in-phase and quadrature signals, and the modulus of the in-phase and quadrature signals.

[0046] The pulse coefficient adjusts the basic pulse based on the first peak clipping threshold and other factors to obtain a peak clipping pulse, taking into account the waveform of the in-phase and quadrature signals, so that the peak clipping pulse has a better peak clipping effect.

[0047] Step 106: Calculate the peak clipping pulse based on the basic pulse and the pulse coefficient.

[0048] The clipped pulse is the product of the basic pulse and the pulse coefficient.

[0049] Step 107: Subtract the peak-clipped pulse from the in-phase and quadrature signals to obtain a peak-cancelled signal.

[0050] Step 108: Determine the modulus of the signal after peak cancellation.

[0051] After peak cancellation, hard peak clipping is used to further process the peak-canceled signal to improve the peak clipping effect.

[0052] Step 109: Determine a hard peak-clipped signal based on the peak-canceled signal, the modulus of the peak-canceled signal, and a preset second peak-clipped threshold.

[0053] In the embodiments of the present application, different filter coefficients can be used to determine base pulses of different waveforms. Based on the peak type, a base pulse that is more compatible with the in-phase orthogonal signal can be selected from the different base pulses. The resulting peak-clipped pulse has a better single-shot peak-clipping effect, eliminating the need for multiple iterations, reducing computational complexity and system latency associated with multiple iterations. Furthermore, combining peak cancellation with hard peak clipping can further enhance the peak-clipping effect.

[0054] In one embodiment of the present application, determining the type of the peak based on the peak value and the first peak clipping threshold includes:

[0055] Calculate the type decision threshold based on the peak value and the first peak clipping threshold;

[0056] determining the type of the peak based on signal points adjacent to the signal point corresponding to the peak and a type decision threshold;

[0057] When the modulus of the preceding signal point adjacent to the signal point corresponding to the peak is less than the type decision threshold, and the modulus of the succeeding signal point adjacent to the signal point corresponding to the peak is less than the type decision threshold, the peak type is a spike.

[0058] When the modulus of the preceding signal point adjacent to the signal point corresponding to the peak is not less than the type decision threshold, and the modulus of the succeeding signal point adjacent to the signal point corresponding to the peak is less than the type decision threshold, the type of the peak is a forward platform.

[0059] When the modulus value of the previous signal point adjacent to the signal point corresponding to the peak is less than the type decision threshold, and the modulus value of the subsequent signal point adjacent to the signal point corresponding to the peak is not less than the type decision threshold, the type of the peak is the backward platform;

[0060] When the modulus value of the previous signal point adjacent to the signal point corresponding to the peak is not less than the type decision threshold, and the modulus value of the subsequent signal point adjacent to the signal point corresponding to the peak is not less than the type decision threshold, the type of the peak is the wide platform.

[0061] Based on Equation (4), calculate the type decision threshold.

[0062] T p (n) = b × T1 + (1 - b) × a(n) (4)

[0063] Where, T p (n) is used to represent the type decision threshold, b is the adjustment coefficient, 0 < b < 1, b is set according to actual requirements. The smaller the value of b, the better the error vector magnitude after peak clipping, but there are more residual peaks; the larger the value of b, the smaller the possibility of residual peaks after peak clipping, but the worse the error vector magnitude.

[0064] Taking 4 types of peaks as the types, the type division of the peaks is described, and the specific division basis is shown in Table 1.

[0065] Table 1 Peak Types and Their Discrimination Conditions

[0066] serial number type Judgment conditions 1 Spikes <![CDATA[a(n-1)<T p (n)&a(n+1)<T p (n)]]> 2 Forward Platform <![CDATA[a(n-1)≥T p (n)&a(n+1)<T p (n)]]> 3 Backward Platform <![CDATA[a(n-1)<T p (n)&a(n+1)≥T p (n)]]> 4 Wide platform <![CDATA[a(n-1)≥T p (n)&a(n+1)≥T p (n)]]>

[0067] Schematic diagrams of the envelope waveforms of 4 types of peaks (Type1-Type 4) are as Figure 2 shown. Where, envelope is used to represent the signal envelope, peak is used to represent the peak, and threshold is used to represent the first peak clipping threshold.

[0068] In the embodiments of the present application, the peaks are classified according to the characteristics of the signal points adjacent to the signal points corresponding to the peaks. This classification method considers the characteristics of the waveforms near the peaks and can improve the peak clipping effect of subsequent peak cancellation.

[0069] In actual application scenarios, other classification methods can also be used. For example, if a(n - 1) < T p (n) & a(n + 1) < T p (n), it is the first category, and others are the second category.

[0070] In an embodiment of the present application, based on the first peak clipping threshold, the in-phase quadrature signal, and the modulus value of the in-phase quadrature signal, calculate the pulse coefficient, including:

[0071] The pulse coefficient is determined as follows: the difference between the modulus of the in-phase and quadrature signals and the first peak clipping threshold multiplied by the quotient of the modulus of the in-phase and quadrature signals and the modulus of the in-phase and quadrature signals.

[0072]

[0073] The pulse coefficient is calculated using formula (5), where x(n) is used to characterize the in-phase orthogonal signal and c(n) is used to characterize the pulse coefficient.

[0074] In one embodiment of the present application, determining the hard peak-clipped signal based on the peak-cancelled signal, the modulus of the peak-cancelled signal, and a preset second peak clipping threshold includes:

[0075] When the modulus of the peak-canceled signal is not greater than the second peak clipping threshold, determining that the hard-clipped signal is a peak-canceled signal;

[0076] When the modulus of the peak cancellation signal is greater than the second peak clipping threshold, the hard peak clipping signal is determined to be: the second peak clipping threshold multiplied by the quotient of the peak cancellation signal and the modulus of the peak cancellation signal.

[0077] After a pulse peak clipping, most of the peaks have been removed; however, due to problems such as peak omission and peak regeneration, a small amount of peaks may still remain. Therefore, the embodiment of the present application performs hard peak clipping again to ensure effective peak clipping effect and peak-to-average power ratio.

[0078] Specifically, formula (6) can be used to perform hard peak clipping.

[0079]

[0080] in, It is used to characterize the modulus of the signal after peak cancellation, and T2 is used to characterize the second peak clipping threshold. Used to characterize the signal after peak cancellation, Used to characterize hard-clipped signals.

[0081] The embodiment of the present application performs hard peak clipping based on the relationship between the modulus value of the signal after peak cancellation and the second peak clipping threshold, which can further improve the peak clipping effect.

[0082] The following describes the generation of basic pulses using four types of peaks as examples.

[0083] The first type is a spike.

[0084] In one embodiment of the present application, when the type of peak is a spike, the filter is a 2M+1 order finite length unit impulse response FIR low-pass filter, and the coefficient of the FIR low-pass filter is the basic pulse; the passband edge of the FIR low-pass filter is not less than the effective bandwidth of the in-phase orthogonal signal, the passband ripple is less than a preset first threshold, and the stopband attenuation is greater than a preset second threshold, and the first threshold and the second threshold are determined by the order of the FIR low-pass filter.

[0085] The basic pulse corresponding to this type of peak has good frequency domain characteristics and has a similar effective bandwidth to the signal, thereby reducing the out-of-band components of the signal after peak clipping, having a flat in-band characteristic, and meeting the FIR low-pass filter characteristics.

[0086] The passband ripple is typically less than 6dB, meaning the first threshold is 6dB. Within a reasonable range, the smaller the better, minimizing distortion of the passband signal. However, when the order is fixed, setting the passband ripple too small can degrade transition band performance. This reasonable range is determined by the filter order. A larger filter order increases the range of tolerable passband ripple and stopband attenuation. Therefore, when designing a filter, all three factors must be considered based on the actual system requirements.

[0087] The stopband attenuation must be less than the out-of-band spectrum emission mask specified by the communication protocol, at least 25dB lower than the protocol requirement. For example, 802.11n requires the out-of-band spurious signal of the HT_MF signal to be less than -45dB. With a certain margin, the stopband attenuation must be set to at least 70dB, i.e., the second threshold is 70dB. Within a reasonable range, the higher the stopband attenuation, the better, as this minimizes the impact of pulses on out-of-band components. However, if the order is fixed, setting the stopband attenuation too high may degrade in-band error vector magnitude performance.

[0088] The second type, the peak type is a forward platform.

[0089] In one embodiment of the present application, when the type of peak is a forward platform, the filter is a 2M+1 order FIR low-pass filter; a zero-value tap is added to the tail of the original even-symmetric coefficient sequence of the 2M order FIR low-pass filter to generate a coefficient sequence of the 2M+1 order FIR low-pass filter, and the coefficient sequence is the basic pulse; the passband edge of the 2M order FIR low-pass filter is not less than the effective bandwidth of the signal, the passband ripple is less than a preset first threshold, and the stopband attenuation is greater than a preset second threshold, and the first threshold and the second threshold are determined by the order of the FIR low-pass filter.

[0090] According to the requirements of the first category for passband edge, passband ripple, and stopband attenuation, a 2M even-order FIR low-pass filter is designed, and a zero value is added at the end to form a 2M+1 order filter. The point before the center of the basic pulse has the same pulse intensity as the center position.

[0091] The third type is the backward platform.

[0092] In one embodiment of the present application, when the type of peak is a backward platform, the filter is a 2M+1 order FIR low-pass filter; a zero-value tap is added to the head of the original even-symmetric coefficient sequence of the 2M order FIR low-pass filter to generate a coefficient sequence of the 2M+1 order FIR low-pass filter, and the coefficient sequence is the basic pulse; the passband edge of the 2M order FIR low-pass filter is not less than the effective bandwidth of the signal, the passband ripple is less than a preset first threshold, and the stopband attenuation is greater than a preset second threshold, and the first threshold and the second threshold are determined by the order of the FIR low-pass filter.

[0093] According to the requirements of the first category for passband edge, passband ripple, and stopband attenuation, a 2M even-order FIR low-pass filter is designed. Finally, a zero value is added to its head to form a 2M+1 order filter. The intensity of the point after the center of the basic pulse is consistent with the pulse at the center.

[0094] The fourth type, the peak type is a wide platform.

[0095] In one embodiment of the present application, when the peak type is a wide platform, the filter is a 2M+1 order FIR low-pass filter, and the coefficient of the FIR low-pass filter is the basic pulse; the passband ripple is less than a preset first threshold, and the stopband attenuation is greater than a preset second threshold, and the first threshold and the second threshold are determined by the order of the FIR low-pass filter.

[0096] The passband frequency can be smaller than the signal bandwidth; the passband ripple requirement is the same as the first category, and the stopband attenuation still needs to be smaller than the protocol requirement, but there is no need to consider such a large margin. For example, 10dB lower than the protocol requirement is sufficient.

[0097] The passband edge of the fourth category is smaller than the passband edges of the first, second and third categories, and the stopband attenuation of the fourth category is smaller than the stopband attenuation of the first, second and third categories.

[0098] Taking the basic pulse with length L=13 as an example, the basic pulses corresponding to the four peak types are as follows: Figure 3 As shown in the figure, the horizontal axis 0 is the pulse center position, corresponding to the detected peak position. h1(n)-h4(n) are different basic pulses.

[0099] The length of the basic pulse is an odd number. The longer the length, the better the out-of-band spectrum performance, the worse the in-band error vector magnitude, and the greater the system delay. The same is true in reverse. The appropriate pulse length needs to be set according to the actual system requirements.

[0100] In any of the above embodiments, by configuring pulses tailored to different types of peaks, the single-shot peak clipping effect is enhanced. Combined with hard clipping, peak-to-average power ratio performance is strictly guaranteed, avoiding multiple iterations of pulse clipping. Because the basic pulse has good spectral characteristics and the peak amplitude after single pulse clipping is already very small, the impact of the final hard clipping operation is negligible. Therefore, any of the above embodiments can ensure that the resulting signal has good spectral characteristics and control out-of-band spurious components in the frequency domain of the clipped signal.

[0101] like Figure 4 Figure 2 shows the waveforms of signal envelopes before and after peak clipping. Original is used to represent in-phase orthogonal signals, Peak-related PC-CFR is used to represent hard-clipped signals obtained using the method provided by this application without iteration, and Traditional PC-CFR is used to represent the clipped signal obtained using an existing peak cancellation-based crest factor reduction method without iteration. This comparison shows that the solution provided by this application produces fewer residual peaks and lower intensities than existing solutions.

[0102] like Figure 5 The figure shows a comparison of power spectrum densities of different signals. The horizontal axis is frequency and the vertical axis is power spectrum density. Peak-related+Hard is used to characterize the power spectrum density obtained by using the solution provided by this application. Traditional+Hard is used to characterize the power spectrum density obtained by using the existing solution. Compared with the solution provided by this application, its out-of-band spurious components are stronger. Hard Clipping is used to characterize the power spectrum density obtained by directly performing hard peak clipping without performing peak cancellation. Its out-of-band spurious components are serious. Mask is used to characterize the signal emission spectrum mask specified by the protocol. Figure 5 It can be seen that the solution provided by this application has better spectrum performance.

[0103] like Figure 6The figure shows a complementary cumulative distribution function curve, with the horizontal axis representing the peak-to-average power ratio and the vertical axis representing the probability that the peak-to-average power ratio is greater than the horizontal axis value. Original corresponds to the in-phase orthogonal signal before peak clipping, Peak-related corresponds to the signal after peak cancellation in this application, i.e., without performing hard peak clipping in this application, Traditional corresponds to the signal obtained using the existing solution, and Peak-related+Hard corresponds to the signal after hard peak clipping obtained using the solution in this application. By comparison, it can be found that the solution provided by this application has a smaller peak-to-average power ratio.

[0104] like Figure 7 As shown, the method provided by the present application is used for the peak clipping module of the transmitting system, including single pulse peak clipping, namely steps 101 to 107, and also including hard peak clipping, namely steps 108 and 109.

[0105] like Figure 8 As shown, the embodiment of the present application provides a crest factor reduction device based on peak cancellation, comprising:

[0106] The peak determination module 801 is configured to calculate the modulus of the in-phase and quadrature signals based on the in-phase and quadrature components of the in-phase and quadrature signals; and determine the peak value based on the modulus of the in-phase and quadrature signals and a preset first peak clipping threshold.

[0107] The peak cancellation module 802 is configured to determine the type of the peak based on the peak value and the first peak clipping threshold; determine a basic pulse based on the type of the peak; wherein different peak types correspond to different basic pulses, and the basic pulses are determined by a filter coefficient design method, and different basic pulses correspond to different filter coefficients; calculate a pulse coefficient based on the first peak clipping threshold, the in-phase orthogonal signal, and the modulus of the in-phase orthogonal signal; calculate a peak clipping pulse based on the basic pulse and the pulse coefficient; and subtract the peak clipping pulse from the in-phase orthogonal signal to obtain a peak-canceled signal.

[0108] The hard peak clipping module 803 is configured to determine the modulus of the peak cancellation signal; and determine the hard peak clipped signal based on the peak cancellation signal, the modulus of the peak cancellation signal and a preset second peak clipping threshold.

[0109] In one embodiment of the present application, the peak cancellation module 802 is configured to calculate a type decision threshold based on the peak value and the first peak clipping threshold; determine the type of the peak based on signal points adjacent to the signal point corresponding to the peak value and the type decision threshold;

[0110] When the modulus of the preceding signal point adjacent to the signal point corresponding to the peak is less than the type decision threshold, and the modulus of the succeeding signal point adjacent to the signal point corresponding to the peak is less than the type decision threshold, the peak type is a spike.

[0111] When the modulus of the preceding signal point adjacent to the signal point corresponding to the peak is not less than the type decision threshold, and the modulus of the succeeding signal point adjacent to the signal point corresponding to the peak is less than the type decision threshold, the type of the peak is a forward platform.

[0112] When the modulus of the preceding signal point adjacent to the signal point corresponding to the peak is less than the type decision threshold, and the modulus of the following signal point adjacent to the signal point corresponding to the peak is not less than the type decision threshold, the type of the peak is a backward platform;

[0113] When the modulus value of the preceding signal point adjacent to the signal point corresponding to the peak is not less than the type decision threshold, and the modulus value of the succeeding signal point adjacent to the signal point corresponding to the peak is not less than the type decision threshold, the type of the peak is a wide platform.

[0114] In one embodiment of the present application, the peak cancellation module 802 is configured to determine the pulse coefficient as: the difference between the modulus of the in-phase and quadrature signals and the first peak clipping threshold, multiplied by the quotient of the modulus of the in-phase and quadrature signals and the modulus of the in-phase and quadrature signals.

[0115] In one embodiment of the present application, the hard peak clipping module 803 is configured to determine that the hard peak clipping signal is a peak cancellation signal when the modulus of the peak cancellation signal is not greater than the second peak clipping threshold; and when the modulus of the peak cancellation signal is greater than the second peak clipping threshold, determine that the hard peak clipping signal is: the second peak clipping threshold multiplied by the quotient of the peak cancellation signal and the modulus of the peak cancellation signal.

[0116] An embodiment of the present application provides a computer program product, including a computer program / instruction, which implements the method of any of the above embodiments when the computer program / instruction is executed by a processor.

[0117] Furthermore, although exemplary embodiments have been described herein, the scope includes any and all embodiments based on the present application having equivalent elements, modifications, omissions, combinations (e.g., solutions that overlap various embodiments), adaptations, or changes. Although several embodiments are described separately for a wireless communication method and a wireless communication component, it should be noted that the method details described in the wireless communication component description can also be incorporated into various embodiments of the wireless communication method, and vice versa.

[0118] The elements of the claims are to be interpreted broadly based on the language employed in the claims and not limited to the examples described in this specification or during the prosecution of the application, which examples are to be construed as non-exclusive. Accordingly, it is intended that the specification and examples be considered as examples only, with the true scope and spirit being indicated by the claims and their full scope of equivalents.

[0119] The order of the steps in this application is merely exemplary and non-restrictive. The order of the steps may be adjusted without affecting the implementation of this application (without disrupting the required logical relationships between the steps), and the resulting embodiments will still fall within the scope of this application.

[0120] The above description is intended to be illustrative and not restrictive. For example, the above examples (or one or more of their solutions) can be used in combination with each other. For example, those of ordinary skill in the art may use other embodiments when reading the above description. In addition, in the above-mentioned specific embodiments, various features can be grouped together to simplify the application. This should not be interpreted as an intention that a disclosed feature that is not required to be protected is necessary for any claim. On the contrary, the subject matter of the present invention may be less than all the features of a specific disclosed embodiment. Thus, the claims are incorporated into the specific embodiments as examples or embodiments, wherein each claim is independently a separate embodiment, and it is considered that these embodiments can be combined with each other in various combinations or arrangements. The scope of the present invention should be determined with reference to the appended claims and the full scope of equivalents to which these claims are entitled.

Claims

1. A peak factor reduction method based on peak type, characterized in that: include: Calculating a modulus of the in-phase and quadrature signals based on the in-phase and quadrature components of the in-phase and quadrature signals; Determining a peak value based on a modulus value of the in-phase and quadrature signals and a preset first peak clipping threshold; determining a type of the peak based on the peak and the first peak clipping threshold; Determining a basic pulse based on the type of the peak; wherein different peak types correspond to different basic pulses, and the basic pulse is determined by a filter coefficient design method, and different basic pulses correspond to different filter coefficients; Calculating a pulse coefficient based on the first peak clipping threshold, the in-phase and quadrature signals, and the modulus of the in-phase and quadrature signals; Calculating a peak clipping pulse based on the basic pulse and the pulse coefficient; Subtracting the peak clipping pulse from the in-phase and quadrature signals to obtain a peak-cancelled signal; Determining a modulus of the signal after peak cancellation; A hard peak-clipped signal is determined based on the peak-canceled signal, the modulus of the peak-canceled signal, and a preset second peak-clipped threshold.

2. The method according to claim 1, wherein Determining the type of the peak based on the peak value and the first peak clipping threshold includes: Calculating a type decision threshold based on the peak value and the first peak clipping threshold; determining the type of the peak based on signal points adjacent to the signal point corresponding to the peak and the type decision threshold; When the modulus of the preceding signal point adjacent to the signal point corresponding to the peak is less than the type decision threshold, and the modulus of the succeeding signal point adjacent to the signal point corresponding to the peak is less than the type decision threshold, the type of the peak is a spike. When the modulus of the preceding signal point adjacent to the signal point corresponding to the peak is not less than the type decision threshold, and the modulus of the following signal point adjacent to the signal point corresponding to the peak is less than the type decision threshold, the type of the peak is a forward platform; When the modulus of the preceding signal point adjacent to the signal point corresponding to the peak is less than the type decision threshold, and the modulus of the following signal point adjacent to the signal point corresponding to the peak is not less than the type decision threshold, the type of the peak is a backward platform; When the modulus value of the preceding signal point adjacent to the signal point corresponding to the peak is not less than the type decision threshold, and the modulus value of the following signal point adjacent to the signal point corresponding to the peak is not less than the type decision threshold, the type of the peak is a wide platform.

3. The method according to claim 1, wherein Calculating a pulse coefficient based on the first peak clipping threshold, the in-phase and quadrature signals, and the modulus of the in-phase and quadrature signals includes: The pulse coefficient is determined by multiplying the difference between the modulus of the in-phase and quadrature signals and the first peak clipping threshold by the quotient of the modulus of the in-phase and quadrature signals and the modulus of the in-phase and quadrature signals.

4. The method according to claim 1, wherein Determining a hard peak-clipped signal based on the peak-cancelled signal, the modulus of the peak-cancelled signal, and a preset second peak-clipped threshold includes: When the modulus of the peak-canceled signal is not greater than the second peak clipping threshold, determining that the hard-clipped signal is a peak-canceled signal; When the modulus of the peak cancellation signal is greater than the second peak clipping threshold, the hard peak clipping signal is determined as: the second peak clipping threshold multiplied by the quotient of the peak cancellation signal and the modulus of the peak cancellation signal.

5. The method according to claim 2, wherein in, When the type of the peak is a spike, the filter is a 2M+1 order finite length unit impulse response FIR low-pass filter, and the coefficient of the FIR low-pass filter is the basic pulse; the passband edge of the FIR low-pass filter is not less than the effective bandwidth of the in-phase orthogonal signal, the passband ripple is less than a preset first threshold, and the stopband attenuation is greater than a preset second threshold, and the first threshold and the second threshold are determined by the order of the FIR low-pass filter.

6. The method according to claim 2, wherein in, When the type of the peak is a forward platform, the filter is a 2M+1 order FIR low-pass filter; a zero-value tap is added to the tail of the original even-symmetric coefficient sequence of the 2M order FIR low-pass filter to generate a coefficient sequence of the 2M+1 order FIR low-pass filter, and the coefficient sequence is the basic pulse; the passband edge of the 2M order FIR low-pass filter is not less than the effective bandwidth of the signal, the passband ripple is less than a preset first threshold, and the stopband attenuation is greater than a preset second threshold, and the first threshold and the second threshold are determined by the order of the FIR low-pass filter.

7. The method according to claim 2, wherein in, When the type of the peak is a backward platform, the filter is a 2M+1 order FIR low-pass filter; a zero-value tap is added to the head of the original even-symmetric coefficient sequence of the 2M order FIR low-pass filter to generate a coefficient sequence of the 2M+1 order FIR low-pass filter, and the coefficient sequence is the basic pulse; the passband edge of the 2M order FIR low-pass filter is not less than the effective bandwidth of the signal, the passband ripple is less than a preset first threshold, and the stopband attenuation is greater than a preset second threshold, and the first threshold and the second threshold are determined by the order of the FIR low-pass filter.

8. The method according to claim 2, wherein in, When the type of the peak is a wide platform, the filter is a 2M+1 order FIR low-pass filter, and the coefficient of the FIR low-pass filter is the basic pulse; the passband ripple is less than a preset first threshold, and the stopband attenuation is greater than a preset second threshold, and the first threshold and the second threshold are determined by the order of the FIR low-pass filter.

9. A crest factor reduction device based on peak cancellation, characterized in that: include: a peak value determination module configured to calculate a modulus value of the in-phase and quadrature signals based on the in-phase and quadrature components of the in-phase and quadrature signals; Determining a peak value based on a modulus value of the in-phase and quadrature signals and a preset first peak clipping threshold; a peak cancellation module configured to determine a type of the peak based on the peak and the first peak clipping threshold; Determining a basic pulse based on the type of the peak; wherein different types of peaks correspond to different basic pulses, and the basic pulses are determined by a filter coefficient design method, and different basic pulses correspond to different filter coefficients; calculating a pulse coefficient based on the first peak clipping threshold, the in-phase orthogonal signal, and the modulus of the in-phase orthogonal signal; calculating a peak clipping pulse based on the basic pulse and the pulse coefficient; and subtracting the peak clipping pulse from the in-phase orthogonal signal to obtain a peak-canceled signal; The hard peak clipping module is configured to determine the modulus of the peak cancellation signal; and determine the hard peak clipping signal based on the peak cancellation signal, the modulus of the peak cancellation signal and a preset second peak clipping threshold.

10. A computer program product comprising a computer program / instructions, characterized in that When the computer program / instructions are executed by a processor, the method according to any one of claims 1 to 8 is implemented.

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