Radio frequency transmission system and signal compensation device and signal compensation method thereof

Abstract

The application provides a radio frequency transmitting system and a signal compensation device and method thereof. The signal compensation device comprises a coefficient storage module for storing a first compensation coefficient and a second compensation coefficient of a signal compensation model, wherein the first compensation coefficient is used for realizing nonlinear distortion pre-compensation and radio frequency passband unevenness pre-compensation, and the second compensation coefficient is used for realizing radio frequency passband unevenness pre-compensation; a signal compensation module connected with the coefficient storage module, the signal compensation module is used for compensating a first digital signal received by a digital end according to the power of the first digital signal by using the first compensation coefficient or the second compensation coefficient to generate a second digital signal; wherein the signal compensation device is arranged at the digital end and connected with an analog end to make the analog end obtain the second digital signal. The application sets the coefficient storage module and selects the corresponding compensation coefficient according to the power of the input digital signal, so that an independent passband compensation hardware unit is not needed.

Description

Technical Field

[0001] This application relates primarily to the field of communication technology, and in particular to a radio frequency transmission system and its signal compensation device and method. Background Technology

[0002] Currently, most broadband wireless communication systems use Orthogonal Frequency Division Multiplexing (OFDM) modulation technology. OFDM modulated signals are non-constant envelope signals, and the output power fluctuates over a large range with time. Moreover, the fluctuation amplitude increases with the increase of signal bandwidth, that is, the peak to average power ratio (PAPR) is high, reaching 12.5dB.

[0003] At the transmitting end, to achieve distortion-free signal transmission, the digital-to-analog converter (DAC) in the transmission link is required to have higher accuracy and a wider dynamic range, but this introduces nonlinear distortion into the system. On the other hand, the power amplifier (PA) in the transmission link is required to operate within a wide dynamic linear range. For the PA, a power back-off scheme is needed to meet the dynamic linear range requirement, which directly leads to a significant reduction in PA efficiency. Digital pre-distortion (DPD) is the mainstream technology for solving the problem of low PA efficiency. By pre-distorting high-power signals, it prevents high-power signals from entering the nonlinear amplification region of the PA and causing signal distortion. Meanwhile, the analog end of the transmitting system has many nonlinear factors and inconsistent passband response characteristics, which can cause various non-ideal signal distortions such as nonlinear distortion and RF passband flatness. Therefore, before signal transmission, in addition to using DPD for nonlinear distortion compensation, the digital end also needs to perform pre-compensation for RF passband flatness.

[0004] However, existing solutions often implement pre-compensation for RF passband unevenness and pre-compensation for nonlinear distortion using two separate modules, resulting in significant hardware overhead, chip area, and product cost. Summary of the Invention

[0005] This application addresses the aforementioned technical problems by providing a radio frequency transmission system and its signal compensation device and method, which can reduce hardware overhead, chip area, and product cost.

[0006] To address the aforementioned technical problems, this application provides a signal compensation device for an RF transmission system. The RF transmission system includes a digital terminal and an analog terminal, comprising: a coefficient storage module for storing a first compensation coefficient and a second compensation coefficient of a signal compensation model, wherein the first compensation coefficient is used to implement nonlinear distortion pre-compensation and RF passband unevenness pre-compensation, and the second compensation coefficient is used to implement RF passband unevenness pre-compensation; and a signal compensation module connected to the coefficient storage module, wherein the signal compensation module is used to compensate the first digital signal received by the digital terminal using the first compensation coefficient or the second compensation coefficient to generate a second digital signal; wherein the signal compensation device is disposed at the digital terminal and connected to the analog terminal so that the analog terminal obtains the second digital signal.

[0007] In one embodiment of this application, the signal compensation module is configured to: compensate the first digital signal with the first compensation coefficient in response to the power of the first digital signal belonging to a first power range; and compensate the first digital signal with the second compensation coefficient in response to the power of the first digital signal belonging to a second power range, wherein the upper limit of the power value of the second power range is less than the lower limit of the power value of the first power range.

[0008] In one embodiment of this application, the signal compensation device further includes a coefficient calibration module connected to the coefficient storage module. The coefficient calibration module is configured to: when the signal compensation module does not perform compensation, compare the first digital signal at the digital end with the analog signal amplified by the power amplifier at the analog end, and obtain the first compensation coefficient and the second compensation coefficient based on the comparison result.

[0009] In one embodiment of this application, the signal compensation model includes a compensation coefficient matrix, wherein both the first compensation coefficient and the second compensation coefficient include diagonal elements of the compensation coefficient matrix, and the signal compensation module is configured to perform a convolution operation between the diagonal elements and the first digital signal to generate the second digital signal.

[0010] This application also provides a radio frequency transmission system, including: a digital terminal equipped with the aforementioned signal compensation device; and an analog terminal connected to the signal compensation device.

[0011] This application also provides a signal compensation method for a radio frequency transmission system, applied to the signal compensation device described above, comprising: obtaining a first compensation coefficient and a second compensation coefficient of a signal compensation model, wherein the first compensation coefficient is used to achieve nonlinear distortion pre-compensation and radio frequency passband unflatness pre-compensation, and the second compensation coefficient is used to achieve the radio frequency passband unflatness pre-compensation; obtaining a first digital signal, and selecting the first compensation coefficient or the second compensation coefficient to compensate the first digital signal according to the power of the first digital signal to generate a second digital signal.

[0012] In one embodiment of this application, the step of selecting to compensate the first digital signal with the first compensation coefficient or the second compensation coefficient based on the power of the first digital signal to generate a second digital signal includes: compensating the first digital signal with the first compensation coefficient in response to the power of the first digital signal belonging to a first power range; and compensating the first digital signal with the second compensation coefficient in response to the power of the first digital signal belonging to a second power range, wherein the upper limit of the power value of the second power range is less than the lower limit of the power value of the first power range.

[0013] In one embodiment of this application, the signal compensation model includes a compensation coefficient matrix, the first compensation coefficient or the second compensation coefficient includes the diagonal elements of the compensation coefficient matrix, and the step of selecting the first compensation coefficient or the second compensation coefficient to compensate the first digital signal according to the power of the first digital signal to generate a second digital signal includes: performing a convolution operation between the diagonal elements and the first digital signal to generate the second digital signal.

[0014] In one embodiment of this application, the number of the first compensation coefficients is multiple, and the step of selecting the first compensation coefficient or the second compensation coefficient to compensate the digital signal according to the power of the first digital signal to generate a second digital signal includes: selecting a target compensation coefficient from multiple first compensation coefficients according to the amplitude of the first digital signal, wherein the target compensation coefficient is used to change the amplitude of the second digital signal by a preset degree.

[0015] In one embodiment of this application, the method further includes: when the signal compensation module does not perform compensation, comparing the first digital signal at the digital end with the analog signal amplified by the power amplifier at the analog end, and obtaining the first compensation coefficient and the second compensation coefficient based on the comparison result, wherein neither the digital signal at the digital end nor the analog signal amplified by the analog end has undergone the nonlinear distortion pre-compensation and the radio frequency passband unevenness pre-compensation.

[0016] Compared with the prior art, this application has the following advantages: By setting a coefficient storage module that stores two types of compensation coefficients in the signal compensation device and selecting the corresponding compensation coefficient according to the power of the input digital signal, this application can realize simultaneous RF passband unevenness compensation and nonlinear distortion compensation for signals with different power, or only RF passband unevenness compensation. This allows the two types of compensation functions to be implemented in the same signal compensation device without the need to set up a separate passband compensation hardware unit, thereby effectively reducing hardware overhead, chip area of ​​the RF transmission system and product cost. Attached Figure Description

[0017] The accompanying drawings are included to provide a further understanding of this application; they are incorporated into and constitute a part of this application. The drawings illustrate embodiments of this application and, together with this specification, serve to explain the principles of this application. In the drawings: Figure 1 This is a simplified block diagram of a radio frequency transmission system; Figure 2 This is a simplified block diagram of a radio frequency transmission system according to an embodiment of this application; Figure 3 This is a simplified block diagram of a signal compensation device according to an embodiment of this application; Figure 4 This is a schematic diagram of the process of a signal compensation module in one embodiment of the present application compensating a first digital signal using a first compensation coefficient or a second compensation coefficient; Figure 5 This is a flowchart of a signal compensation method for a radio frequency transmission system according to an embodiment of this application. Detailed Implementation

[0018] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are merely some examples or embodiments of this application. For those skilled in the art, these drawings can be applied to other similar scenarios without creative effort. Unless obvious from the context or otherwise specified, the same reference numerals in the drawings represent the same structures or operations.

[0019] As indicated in this application and claims, unless the context clearly indicates otherwise, the words "a," "an," "an," and / or "the" are not specifically singular and may include plural forms. Generally speaking, the terms "comprising" and "including" only indicate the inclusion of explicitly identified steps and elements, which do not constitute an exclusive list, and the method or apparatus may also include other steps or elements.

[0020] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of this application. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following drawings denote similar items; therefore, once an item is defined in one drawing, it need not be further discussed in subsequent drawings.

[0021] In the description of this application, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is usually based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this application and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this application; the directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0022] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, these terms have no special meaning and therefore should not be construed as limiting the scope of protection of this application. In addition, although the terminology used in this application is selected from commonly known and used terms, some terms mentioned in this application's specification may have been chosen by the applicant according to his or her judgment, and their detailed meanings are explained in the relevant sections of this description. Moreover, this application should be understood not only through the actual terms used, but also through the meaning implied by each term.

[0023] It should be understood that when a component is referred to as "on another component," "connected to another component," "coupled to another component," or "in contact with another component," it can be directly on, connected to, coupled to, or in contact with that other component, or there may be an intervening component. In contrast, when a component is referred to as "directly on another component," "directly connected to," "directly coupled to," or "directly in contact with" another component, there is no intervening component. Similarly, when a first component is referred to as "electrically contacting" or "electrically coupled to" a second component, there is an electrical path between the first and second components that allows current to flow. This electrical path may include capacitors, coupled inductors, and / or other components that allow current to flow, even if there is no direct contact between the conductive components.

[0024] Flowcharts are used in this application to illustrate the operations performed by the system according to embodiments of this application. It should be understood that the preceding or following operations are not necessarily performed in exact order. Instead, various steps can be processed in reverse order or simultaneously. Furthermore, other operations may be added to these processes, or one or more steps may be removed from these processes.

[0025] The radio frequency transmission system and signal compensation device and signal compensation method proposed in this application are applicable to radio frequency transmission scenarios, especially to radio frequency transmission scenarios of various broadband wireless communication systems using OFDM modulation.

[0026] Figure 1 A simplified block diagram of a radio frequency transmission system is shown. Figure 1 As shown, the RF transmission system 10 includes a digital terminal 11 and an analog terminal 12. The digital terminal 11 includes a DPD module 111 for digital pre-distortion to compensate for nonlinear distortion, a Tilt Pre-comp module 112 for pre-compensation of RF passband unevenness, and an Other Pre-comp module 113 for other pre-compensation besides DPD and Tilt, such as DC bias compensation and IQ imbalance pre-compensation. A DAC module 114 converts the pre-compensated digital signal into an analog signal. The analog terminal 11 includes an RF path module 121, which is the analog channel for transmitting signals. Its hardware includes an analog baseband filter, a mixer, and other supporting analog circuit units for performing analog filtering, up-conversion, and other processing operations on the signal. The RF path module 121 also includes a PA module 122 for power amplification of the signal. Figure 1The radio frequency transmission system 10 shown uses two independent modules, namely the DPD module 111 and the Tilt Pre-comp module 112, which are used to implement pre-compensation for radio frequency passband unevenness and pre-compensation for nonlinear distortion, respectively. This results in large hardware overhead, chip area and product cost.

[0027] Figure 2 A simplified block diagram of a radio frequency transmission system 20 according to an embodiment of this application is shown. Figure 3 A simplified block diagram of a signal compensation device according to an embodiment of this application is shown. Figure 3 The signal compensation device 211 shown is... Figure 2 The signal compensation device 211 in the text therefore uses the same designation. For example... Figure 2 and Figure 3 As shown, the radio frequency transmission system 20 includes a digital terminal 21 and an analog terminal 22. The digital terminal 21 is equipped with a signal compensation device 211, and the analog terminal 22 is connected to the signal compensation device 211. The signal compensation device 211 includes: a coefficient storage module 31, used to store a first compensation coefficient and a second compensation coefficient of the signal compensation model, wherein the first compensation coefficient is used to realize nonlinear distortion compensation and radio frequency passband unevenness compensation, and the second compensation coefficient is used to realize radio frequency passband unevenness compensation; and a signal compensation module 32, connected to the coefficient storage module 31, used to select the first compensation coefficient or the second compensation coefficient to compensate the first digital signal according to the power of the first digital signal received by the digital terminal 21, so as to generate a second digital signal; wherein the signal compensation device 211 is disposed on the digital terminal 21 and connected to the analog terminal 22 so that the analog terminal 22 obtains the second digital signal.

[0028] This application enables simultaneous RF passband unevenness compensation and nonlinear distortion compensation, or only RF passband unevenness compensation, for signals of different power levels by setting a coefficient storage module 31 in the signal compensation device 211 to store two types of compensation coefficients and selecting the corresponding compensation coefficient according to the power of the input digital signal. This allows both types of compensation functions to be implemented in the same signal compensation device 211 without the need to set up a separate passband compensation hardware unit, thereby effectively reducing hardware overhead, chip area of ​​RF transmission system 20 and product cost.

[0029] In some embodiments, the signal compensation model includes a memory polynomial (MP) model and a generalized memory polynomial (GMP) model. The signal compensation model includes a compensation coefficient matrix, where both the first and second compensation coefficients include diagonal elements of the compensation coefficient matrix. Specifically, when the signal compensation model used is an MP model, both the first and second compensation coefficients are diagonal elements of the MP model's compensation coefficient matrix; when the signal compensation model used is a GMP model, both the first and second compensation coefficients are the upper and lower triangular matrix coefficients and diagonal element coefficients of the GMP model's compensation coefficient matrix. When the first or second compensation coefficient is used to compensate the first digital signal, the signal compensation module 32 is configured to perform a convolution operation between the diagonal elements and the first digital signal to generate a second digital signal. In some embodiments, the coefficient storage module 31 stores the first and second compensation coefficients of the signal compensation model in the form of a lookup table (LUT).

[0030] In some embodiments, the number of first compensation coefficients is multiple, and the signal compensation module 32 is further configured to: select a target compensation coefficient from the multiple first compensation coefficients according to the amplitude of the first digital signal, wherein the target compensation coefficient is used to change the amplitude of the second digital signal by a preset degree, the magnitude of which is determined according to the amplitude range to which the first digital signal belongs. When the power amplifier operates in a range close to its saturation power, amplitude compression occurs, that is, the growth slope of the output signal amplitude as the input amplitude increases is lower than the linear range, resulting in output signal distortion. By setting multiple first compensation coefficients and selecting a target compensation coefficient from the multiple first compensation coefficients according to the amplitude of the first digital signal, the effect of the PA on the nonlinear distortion of signals with different amplitudes can be matched. For example, multiple sets of first compensation coefficients are pre-stored in a one-dimensional LUT table, where the index of the LUT is the amplitude range of the first digital signal. When the amplitude of the first digital signal falls into the high amplitude range, the corresponding first compensation coefficient is selected as the target compensation coefficient. This coefficient will increase the signal amplitude rate by a preset amount to offset the peak clipping effect of the PA on the large peak signal. When the amplitude of the first digital signal falls into the low amplitude range, the first compensation coefficient corresponding to the low amplitude range is selected. At this time, the target compensation coefficient has a smaller gain adjustment range on the first digital signal, matching the characteristic that the PA has little impact on the small peak signal.

[0031] Figure 4 This diagram illustrates a flow chart of a signal compensation module 32 according to an embodiment of the present application, which compensates a first digital signal using a first compensation coefficient or a second compensation coefficient. Figure 4 As shown, in some embodiments, the step of the signal compensation module 32 compensating the first digital signal with a first compensation coefficient or a second compensation coefficient includes: Step S41: Receive the first digital signal. That is, the signal compensation module 32 receives the first digital signal.

[0032] Step S42: Obtain the modulus. Obtain the modulus value of the first digital signal.

[0033] Step S43: Obtain the first compensation coefficient or the second compensation coefficient. For example, the signal compensation module 32 determines whether to use the first compensation coefficient or the second compensation coefficient based on the power of the first digital signal. When it is determined that the first compensation coefficient should be used, the target compensation coefficient is selected from multiple first compensation coefficients in the lookup table in the coefficient storage module 31 based on the magnitude of the first digital signal, i.e., the amplitude of the first digital signal.

[0034] Step S44: Delay the first digital signal. That is, delay the first digital signal by a preset time. The specific duration of the preset time is set so that the delayed first digital signal and the first compensation coefficient or the second compensation coefficient can be convolved.

[0035] Step S45: Convolution. That is, perform a convolution operation on the first digital signal delayed in step S44 and the first compensation coefficient or the second compensation coefficient.

[0036] Step S46: Generate a second digital signal. That is, generate a second digital signal based on the convolution operation result of step S45. The second digital signal is the signal after compensation by the signal compensation module 32.

[0037] In some embodiments, both the first digital signal and the second digital signal are OFDM modulated signals.

[0038] In some embodiments, the signal compensation module 32 is configured to: compensate the first digital signal with a first compensation coefficient in response to the power of the first digital signal belonging to a first power range; and compensate the first digital signal with a second compensation coefficient in response to the power of the first digital signal belonging to a second power range, wherein the upper limit of the power value of the second power range is less than the lower limit of the power value of the first power range. Specifically, when the power of the first digital signal belongs to the first power range, the first digital signal is a high-power signal; when the power of the first digital signal belongs to the second power range, the first digital signal is a low-power signal. This application does not specifically limit the power range of the first and second power ranges. In some embodiments, the high-power signal includes signals in the nonlinear region of the power amplifier, and the first power range includes signals greater than 10 dBm; the low-power signal includes signals in the linear region of the power amplifier, and the second power range includes signals less than or equal to 10 dBm. When transmitting high-power signals, the RF passband unevenness is taken into account in the DPD compensation filter while performing DPD pre-distortion filtering. Since the nonlinear distortion of low-power signals is small and negligible, DPD pre-distortion is not required when transmitting low-power signals. The RF passband unevenness can be compensated by using only the diagonal elements of the DPD pre-distortion filter.

[0039] like Figure 3 As shown, in some embodiments, the signal compensation device 211 further includes a coefficient calibration module 33 connected to the coefficient storage module 31. The coefficient calibration module 33 is configured to: when the signal compensation module 211 does not perform compensation, that is, when the signal compensation module 32 is turned off, compare the digital signal at the digital end with the analog signal amplified by the power amplifier at the analog end, and obtain the first compensation coefficient and the second compensation coefficient based on the comparison result.

[0040] like Figure 2 As shown, in some embodiments, and Figure 1 The radio frequency transmission system 10 is identical to that in the previous system. The digital terminal 21 also includes a DAC module 214 for converting the pre-compensated digital signal into an analog signal; the analog terminal 22 also includes a PA module 222 for power amplification of the signal. This application does not impose specific limitations on the method of obtaining the diagonal coefficients and the upper and lower triangular array coefficients. In some embodiments, by acquiring the digital signal before the DAC module 214 and the analog signal amplified by the PA module 222 after the digital signal passes through the DAC module 214, the two acquired signals are feature aligned and their differences compared, and the diagonal coefficients and the upper and lower triangular array coefficients are obtained through parameter identification.

[0041] like Figure 2As shown, in some embodiments, the analog terminal 11 of the RF transmission system 20 includes an RF path module 221, which is used as an analog channel for transmitting signals. Its hardware components include an analog baseband filter, a mixer, and other supporting analog circuit units, used to perform a series of processing operations such as analog filtering and up-conversion on the signal. The RF path module 221 includes a power amplifier (PA) module 222. In some embodiments, the performance of the RF path module 221 may change after temperature changes, and subsequent recalibration is required. That is, when the signal compensation module 211 does not perform compensation, the digital signal at the digital terminal is compared with the analog signal amplified by the power amplifier at the analog terminal, and the first compensation coefficient and the second compensation coefficient are obtained based on the comparison result.

[0042] In some embodiments, by inputting multiple digital signals with different amplitude ranges into the radio frequency transmission system 10, and acquiring the digital signal before the DAC module 214 and the analog signal amplified by the PA module 222 for each signal, the two signals are feature aligned and the difference is compared to obtain multiple first compensation coefficients for the first digital signal with different amplitude ranges.

[0043] like Figure 2 As shown, in some embodiments, the radio frequency transmission system 20 also includes an other pre-comp module 113 for performing compensations such as DC bias compensation and IQ imbalance pre-compensation.

[0044] Figure 5 A flowchart illustrating a signal compensation method for a radio frequency transmission system according to an embodiment of this application is shown. Figure 5 As shown, this application also provides a signal compensation method 50 for a radio frequency transmission system, applied to the signal compensation device 211 described above, comprising: Step S51: Obtain the first compensation coefficient and the second compensation coefficient of the signal compensation model, wherein the first compensation coefficient is used to realize nonlinear distortion pre-compensation and RF passband unflatness pre-compensation, and the second compensation coefficient is used to realize RF passband unflatness pre-compensation. Step S52: Obtain the first digital signal, and select either the first compensation coefficient or the second compensation coefficient to compensate the first digital signal according to the power of the first digital signal, so as to generate the second digital signal.

[0045] This application achieves simultaneous RF passband unevenness compensation and nonlinear distortion compensation, or only RF passband unevenness compensation, for signals of different power by obtaining the first and second compensation coefficients of the signal compensation model and selecting the corresponding compensation coefficients according to the power of the input digital signal. This allows both types of compensation functions to be implemented in the same signal compensation device without the need to set up a separate passband compensation hardware unit, thereby effectively reducing hardware overhead, chip area of ​​the RF transmission system and product cost.

[0046] In some embodiments, step S52 includes: compensating the first digital signal with a first compensation coefficient in response to the power of the first digital signal belonging to a first power range; and compensating the first digital signal with a second compensation coefficient in response to the power of the first digital signal belonging to a second power range, wherein the upper limit of the power value of the second power range is less than the lower limit of the power value of the first power range.

[0047] In some embodiments, the signal compensation model includes a compensation coefficient matrix, and the first compensation coefficient or the second compensation coefficient includes the diagonal elements of the compensation coefficient matrix. Step S52 includes: performing a convolution operation between the diagonal elements and the first digital signal to generate a second digital signal.

[0048] In some embodiments, the number of first compensation coefficients is multiple, and step S52 includes: selecting a target compensation coefficient from multiple first compensation coefficients according to the amplitude of the first digital signal, wherein the target compensation coefficient is used to change the amplitude of the second digital signal by a preset degree.

[0049] In some embodiments, the signal compensation method 50 further includes, when the signal compensation module does not perform compensation, comparing the first digital signal at the digital end with the analog signal amplified by the power amplifier at the analog end, and calibrating to obtain a first compensation coefficient and a second compensation coefficient based on the comparison result.

[0050] The content and effects of the above-described signal compensation method 50 have been detailed in the section introducing the above-described signal compensation device 211, and will not be repeated here.

[0051] It should be noted that, in order to simplify the description of the present application and thus aid in the understanding of one or more embodiments of the invention, the foregoing description of the embodiments of the present application sometimes combines multiple features into a single embodiment, drawing, or description thereof. However, this disclosure method does not imply that the subject matter of the application requires more features than those mentioned. In fact, the embodiments contain fewer features than all the features of the single embodiments disclosed above.

[0052] In some embodiments, numbers describing the quantity of components and attributes are used. It should be understood that such numbers used to describe embodiments are sometimes modified by the terms "approximately," "approximately," or "generally." Unless otherwise stated, "approximately," "approximately," or "generally" indicates that the numbers are allowed to vary by ±20%. Accordingly, in some embodiments, the numerical parameters used in this application are approximate values, which may be changed depending on the characteristics required by individual embodiments. In some embodiments, numerical parameters should take into account specified significant digits and employ a general method of digit reservation. Although the numerical ranges and parameters used to confirm their breadth of range in some embodiments of this application are approximate values, in specific embodiments, such values ​​are set as precisely as feasible.

Claims

1. A signal compensation device for a radio frequency (RF) transmission system, the RF transmission system comprising a digital terminal and an analog terminal, characterized in that, include: The coefficient storage module is used to store the first compensation coefficient and the second compensation coefficient of the signal compensation model. The first compensation coefficient is used to realize the nonlinear distortion pre-compensation and the radio frequency passband unevenness pre-compensation, and the second compensation coefficient is used to realize the radio frequency passband unevenness pre-compensation. A signal compensation module is connected to the coefficient storage module. The signal compensation module is used to select the first compensation coefficient or the second compensation coefficient to compensate the first digital signal according to the power of the first digital signal received by the digital terminal, so as to generate a second digital signal. The signal compensation device is located at the digital terminal and connected to the analog terminal so that the analog terminal can obtain the second digital signal.

2. The signal compensation device as described in claim 1, characterized in that, The signal compensation module is configured to: compensate the first digital signal using the first compensation coefficient when the power of the first digital signal belongs to a first power range; and compensate the first digital signal using the second compensation coefficient when the power of the first digital signal belongs to a second power range, wherein the upper limit of the power value of the second power range is less than the lower limit of the power value of the first power range.

3. The signal compensation device as described in claim 1, characterized in that, It also includes a coefficient calibration module connected to the coefficient storage module. The coefficient calibration module is configured to: when the signal compensation module does not perform compensation, compare the first digital signal at the digital end with the analog signal amplified by the power amplifier at the analog end, and obtain the first compensation coefficient and the second compensation coefficient based on the comparison result.

4. The signal compensation device as described in claim 1, characterized in that, The signal compensation model includes a compensation coefficient matrix. Both the first compensation coefficient and the second compensation coefficient include the diagonal elements of the compensation coefficient matrix. The signal compensation module is configured to perform a convolution operation between the diagonal elements and the first digital signal to generate the second digital signal.

5. A radio frequency transmitting system, comprising: The digital end is provided with a signal compensation device as described in any one of claims 1-4; The analog terminal is connected to the signal compensation device.

6. A signal compensation method for a radio frequency transmission system, applied to the signal compensation device as described in any one of claims 1-4, characterized in that, include: Obtain a first compensation coefficient and a second compensation coefficient for the signal compensation model, wherein the first compensation coefficient is used to achieve nonlinear distortion pre-compensation and RF passband unflatness pre-compensation, and the second compensation coefficient is used to achieve the RF passband unflatness pre-compensation. A first digital signal is obtained, and the first or second compensation coefficient is selected to compensate the first digital signal according to the power of the first digital signal to generate a second digital signal.

7. The signal compensation method as described in claim 6, characterized in that, The step of selecting to compensate the first digital signal with the first compensation coefficient or the second compensation coefficient based on the power of the first digital signal to generate the second digital signal includes: compensating the first digital signal with the first compensation coefficient in response to the power of the first digital signal belonging to a first power range; and compensating the first digital signal with the second compensation coefficient in response to the power of the first digital signal belonging to a second power range, wherein the upper limit of the power value of the second power range is less than the lower limit of the power value of the first power range.

8. The signal compensation method as described in claim 6, characterized in that, The signal compensation model includes a compensation coefficient matrix. The first compensation coefficient or the second compensation coefficient includes the diagonal elements of the compensation coefficient matrix. The step of selecting the first compensation coefficient or the second compensation coefficient to compensate the first digital signal according to the power of the first digital signal to generate a second digital signal includes: performing a convolution operation between the diagonal elements and the first digital signal to generate the second digital signal.

9. The signal compensation method as described in claim 6, characterized in that, The number of the first compensation coefficients is multiple, and the step of selecting either the first compensation coefficient or the second compensation coefficient to compensate the digital signal based on the power of the first digital signal to generate the second digital signal includes: A target compensation coefficient is selected from a plurality of first compensation coefficients based on the amplitude of the first digital signal, wherein the target compensation coefficient is used to change the amplitude of the second digital signal by a preset degree.

10. The signal compensation method as described in claim 6, characterized in that, Also includes: When the signal compensation module does not perform compensation, the first digital signal at the digital end is compared with the analog signal amplified by the power amplifier at the analog end, and the first compensation coefficient and the second compensation coefficient are obtained based on the comparison result.

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