RF channel design method for non-cooperative interference cancellation in communication systems

Abstract

The present application belongs to the field of communication technology, and specifically discloses a non-cooperative interference cancellation RF channel design method applied to a communication system, including: determining a sub-band intra-band design index, an inter-sub-band design index, and an amplitude modulation frequency conversion linearity index; designing a sub-band division circuit based on each index; and designing an amplitude modulation frequency conversion module and a gain control module corresponding to each sub-band based on the amplitude modulation frequency conversion linearity index. The design method of the present application is applied to each RF receiving channel in a multi-antenna array system, and the signal power in each sub-band is controlled within an appropriate range through a multi-channel, multi-sub-band gain control module. In combination with the linearity design of the sub-band division circuit and the amplitude modulation frequency conversion module, the high-power interference signal and the low-power useful signal are simultaneously and undistortedly provided to the non-cooperative interference cancellation circuit, suppressing the high-power broadband interference signal while not damaging the useful signal. The RF receiving channel has the characteristics of instantaneous large dynamic range and high linearity.

Description

Technical Field

[0001] The present application relates to the field of communication technology, and more specifically, to a non-cooperative interference cancellation radio frequency channel design method applied to a communication system. Background Art

[0002] Communication equipment is severely impacted by high-power blocking interference, necessitating further improvements in its anti-interference capabilities. Interference cancellation can effectively address non-cooperative blocking interference, but relying solely on the device's own RF signal path circuitry to achieve interference cancellation presents numerous challenges. Existing communication equipment's RF signal path circuitry is designed based on the power range of the communication signal. When receiving high-power interference signals, components such as the power amplifier and mixer within the RF signal path circuitry easily enter a nonlinear region, distorting the interference signal and making cancellation difficult. Simply reducing the gain of the RF signal path reduces the sensitivity of the communication equipment, making existing communication equipment's RF signal path circuitry ineffective for interference cancellation. Summary of the Invention

[0003] In view of the defects of the prior art, the purpose of the present application is to provide a high-power interference signal and a low-power useful signal to a non-cooperative interference cancellation circuit simultaneously without distortion.

[0004] To achieve the above objectives, in a first aspect, the present application provides a non-cooperative interference cancellation radio frequency channel design method applied to a communication system, comprising:

[0005] Determine the intra-subband design index, inter-subband design index, and AM frequency conversion linearity index. The intra-subband design index is used to characterize the group delay flatness and attenuation flatness between different frequency points in the same sub-band. The inter-subband design index is used to characterize the group delay consistency and attenuation consistency between different sub-bands. The AM frequency conversion linearity index is used to characterize the linearity of the AM frequency conversion module during signal processing.

[0006] Based on the intra-subband design index and the inter-subband design index, a sub-band division circuit is designed, where the sub-band division circuit is used to evenly divide the RF receiving working frequency band into multiple sub-bands;

[0007] Based on the AM / F conversion linearity index, the AM / F conversion module and gain control module corresponding to each sub-band are designed;

[0008] Among them, the amplitude modulation and frequency conversion module is used to perform amplitude modulation and frequency conversion processing on the signal on the sub-band, and output the processed signal to the non-cooperative interference cancellation circuit. The gain control module is used to control the gain used for the amplitude modulation processing of the amplitude modulation and frequency conversion module based on the sub-band signal power, so that each device in the amplitude modulation and frequency conversion module operates in the linear region.

[0009] In one possible implementation, the sub-band division circuit includes: a low noise amplifier, a power divider, and a plurality of sub-band filters, wherein the passband bandwidth of the sub-band filter is equal to the bandwidth of a sub-band in the RF receiving operating frequency band;

[0010] The low noise amplifier is used to amplify the received signal and output the amplified signal to the power divider;

[0011] The power divider is used to evenly distribute the received signal to each sub-band filter according to power;

[0012] The sub-band filter is used to perform channelization filtering on the received signal based on the passband bandwidth and output the filtered signal to the amplitude modulation and frequency conversion module.

[0013] In one possible implementation, a subband division circuit is designed based on an intra-subband design index and an inter-subband design index, including:

[0014] Based on the intra-subband design indicators and inter-subband design indicators, each subband filter is iteratively optimized by analyzing the simulated subband filter amplitude-frequency curve, subband filter phase-frequency curve and subband filter group delay curve.

[0015] In a possible implementation, the method further includes:

[0016] After iteratively optimizing each sub-band filter, the frequency sweep signal is input to the sub-band division circuit;

[0017] Determining delay differences and attenuation differences between different sub-bands based on signals output by each sub-band filter;

[0018] Based on the delay differences and attenuation differences between different sub-bands, compensation information corresponding to each sub-band is determined. The compensation information is used to instruct the non-cooperative interference cancellation circuit to perform phase compensation and amplitude compensation on the signal on the sub-band.

[0019] In a possible implementation, the amplitude modulation frequency conversion module is composed of a mixer, a coupler, a signal amplitude modulation module, an intermediate frequency filter, and an analog-to-digital converter connected in cascade order;

[0020] The gain control module includes a detector and a gain control calculation unit. The detector is used to detect the coupled signal provided by the coupler and convert the power of the coupled signal into a voltage signal. The gain control calculation unit is used to output a gain control signal to the signal amplitude modulation module based on the voltage signal.

[0021] In a second aspect, the present application provides a radio frequency channel circuit, which is obtained by applying any of the above-mentioned radio frequency channel design methods for non-cooperative interference cancellation applied to a communication system, and the radio frequency channel circuit includes: a sub-band division circuit and an amplitude modulation and frequency conversion module and a gain control module corresponding to each sub-band;

[0022] The sub-band division circuit is used to evenly divide the radio frequency receiving working frequency band into multiple sub-bands;

[0023] The amplitude modulation and frequency conversion module is used to perform amplitude modulation and frequency conversion on the signal on the sub-band, and output the processed signal to the non-cooperative interference cancellation circuit;

[0024] The gain control module is used to control the gain used in the amplitude modulation processing of the amplitude modulation frequency conversion module based on the sub-band signal power, so that each device in the amplitude modulation frequency conversion module operates in the linear region.

[0025] In one possible implementation, the sub-band division circuit includes: a low noise amplifier, a power divider, and a plurality of sub-band filters, wherein the passband bandwidth of the sub-band filter is equal to the bandwidth of a sub-band in the RF receiving operating frequency band;

[0026] The low noise amplifier is used to amplify the received signal and output the amplified signal to the power divider;

[0027] The power divider is used to evenly distribute the received signal to each sub-band filter according to power;

[0028] The sub-band filter is used to perform channelization filtering on the received signal based on the passband bandwidth and output the filtered signal to the amplitude modulation and frequency conversion module.

[0029] In one possible implementation, a broadband filter is further provided between the low-noise amplifier and the power divider. The passband bandwidth of the broadband filter is equal to the bandwidth of the RF receiving operating band. The broadband filter is used to filter out out-band signals and provide the filtered received signal to the power divider.

[0030] In a possible implementation, the system further includes a signal compensation determination module, which is configured to:

[0031] Inputting a frequency sweep signal to a sub-band division circuit;

[0032] Determining delay differences and attenuation differences between different sub-bands based on signals output by each sub-band filter;

[0033] Based on the delay differences and attenuation differences between different sub-bands, compensation information corresponding to each sub-band is determined. The compensation information is used to instruct the non-cooperative interference cancellation circuit to perform phase compensation and amplitude compensation on the signal on the sub-band.

[0034] In a possible implementation, the amplitude modulation frequency conversion module is composed of a mixer, a coupler, a signal amplitude modulation module, an intermediate frequency filter, and an analog-to-digital converter connected in cascade order;

[0035] The gain control module includes a detector and a gain control calculation unit. The detector is used to detect the coupled signal provided by the coupler and convert the power of the coupled signal into a voltage signal. The gain control calculation unit is used to output a gain control signal to the signal amplitude modulation module based on the voltage signal.

[0036] It can be understood that the beneficial effects of the second aspect mentioned above can be found in the relevant description of the first aspect mentioned above, and will not be repeated here.

[0037] In general, the above technical solutions conceived by this application have the following beneficial effects compared with the existing technologies:

[0038] The design method of the present application can be applied to each RF receiving channel in a multi-antenna array system. Each RF (receiving) channel circuit channels the broadband high-power interference signal through a sub-band division circuit, and uses the idea of ​​"dividing the width into narrowness" in the frequency domain to convert the broadband interference into narrowband interference processing. The signal power in each sub-band is controlled within an appropriate range through a multi-channel, multi-sub-band gain control module, and combined with the linearity design of the sub-band division circuit and the amplitude modulation and frequency conversion module, it is possible to provide the high-power interference signal and the low-power useful signal to the non-cooperative interference cancellation circuit without distortion at the same time, suppressing the high-power broadband interference signal without damaging the useful signal. The RF receiving channel has the characteristics of instantaneous large dynamic range and high linearity. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 1 is a flow chart of a method for designing a non-cooperative interference cancellation radio frequency channel for a communication system according to an embodiment of the present application;

[0040] Figure 2 is a schematic structural diagram of a radio frequency channel circuit provided in an embodiment of the present application;

[0041] Figure 3 This is a schematic diagram of the radio frequency channel circuit provided in an embodiment of the present application applied to a multi-antenna array system.

[0042] Throughout the drawings, the same reference numerals are used to denote the same elements or structures, wherein:

[0043] 10: Sub-band division circuit; 11: Low noise amplifier; 12: Power divider; 13: Sub-band filter; 20: AM frequency conversion module; 21: Mixer; 22: Coupler; 23: Signal AM module; 24: Intermediate frequency filter; 25: Analog-to-digital converter; 30: Gain control module; 31: Detector; 32: Gain control calculation unit. DETAILED DESCRIPTION

[0044] In order to make the purpose, technical solutions and advantages of this application more clear, the following further describes this application in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0045] In the embodiments of this application, words such as "exemplary" or "for example" are used to indicate examples, illustrations, or descriptions. Any embodiment or design described as "exemplary" or "for example" in the embodiments of this application should not be interpreted as being preferred or advantageous over other embodiments or designs. Rather, the use of words such as "exemplary" or "for example" is intended to present the relevant concepts in a concrete manner.

[0046] In the description of the embodiments of the present application, unless otherwise specified, "multiple" means two or more, for example, multiple processing units means two or more processing units, etc.; multiple elements means two or more elements, etc.

[0047] The embodiments of the present application are described below in conjunction with the drawings in the embodiments of the present application.

[0048] Figure 1 FIG. 1 is a flow chart of a non-cooperative interference cancellation radio frequency channel design method for a communication system provided in an embodiment of the present application. Figure 1 As shown, the method includes the following steps S101 to S103.

[0049] Step S101, determining the intra-subband design index, inter-subband design index, and amplitude modulation frequency conversion linearity index. The intra-subband design index is used to characterize the group delay flatness and attenuation flatness between different frequency points in the same subband. The inter-subband design index is used to characterize the group delay consistency and attenuation consistency between different subbands. The amplitude modulation frequency conversion linearity index is used to characterize the linearity of the amplitude modulation frequency conversion module during the signal processing process.

[0050] Step S102 : Based on the intra-subband design index and the inter-subband design index, a sub-band division circuit is designed to evenly divide the RF receiving working frequency band (ie, the communication frequency band) into a plurality of sub-bands.

[0051] Step S103: Designing an AM / F conversion module and a gain control module corresponding to each sub-band based on the AM / F conversion linearity index;

[0052] Among them, the amplitude modulation and frequency conversion module is used to perform amplitude modulation and frequency conversion processing on the signal on the sub-band, and output the processed signal to the non-cooperative interference cancellation circuit. The gain control module is used to control the gain used for the amplitude modulation processing of the amplitude modulation and frequency conversion module based on the sub-band signal power, so that each device in the amplitude modulation and frequency conversion module operates in the linear region.

[0053] Figure 2 : is a schematic diagram of the structure of the radio frequency channel circuit provided in the embodiment of the present application, such as Figure 2 As shown, the radio frequency channel circuit includes a sub-band division circuit 10 and an amplitude modulation and frequency conversion module 20 and a gain control module 30 corresponding to each sub-band.

[0054] Group delay flatness refers to the fact that, within the same sub-band, signals of different frequencies, after processing, arrive at the output end with similar delays. In other words, the signal delay remains flat as the frequency changes. Good group delay flatness means that within the same sub-band, the transmission delay of signals at all frequencies is stable, with no significant delay variations due to frequency variations.

[0055] Attenuation flatness refers to the fact that, within the same sub-band, signals at different frequencies experience similar amplitude attenuation after processing. In other words, signal attenuation remains flat over frequency. Good attenuation flatness means that within the same sub-band, the transmission loss of signals at all frequencies is uniform, with no significant amplitude differences due to frequency variations.

[0056] Meeting the design requirements for intra-subband delay and attenuation flatness means that signal delay and attenuation are uniform within each sub-band, eliminating uneven frequency response. This ensures that signals received across different frequency ranges are accurately processed without signal or frequency distortion, achieving linear processing.

[0057] Group delay consistency refers to the consistency of the time (delay) it takes for the processed signal to reach the output port across different subbands. High group delay consistency means minimal differences in signal transmission delays between subbands, facilitating overall synchronous signal processing.

[0058] Attenuation consistency refers to the consistency of signal amplitude attenuation across different sub-bands after processing. High attenuation consistency means minimal difference in signal transmission loss across sub-bands, facilitating overall signal balance.

[0059] To ensure that the frequency ranges of multiple sub-bands cover all communication frequencies, the passband frequencies of adjacent sub-bands overlap. Communication signals with frequencies within the overlapping region pass through both sub-bands simultaneously. To ensure the linearity of the received signal, the delay and attenuation consistency between sub-bands must meet design requirements.

[0060] Meeting the design requirements for delay and attenuation consistency across subbands means consistent signal processing across different subbands, with the same impact of delay and attenuation. This ensures continuous and smooth signal processing across subbands, without signal jumps or discontinuities, thus achieving linear processing.

[0061] Therefore, by ensuring that the design requirements of intra-subband delay and attenuation flatness and inter-subband delay and attenuation consistency are met, the sub-band division circuit can process the received signal linearly, thereby improving the accuracy and stability of signal processing.

[0062] AM-Frequency Converter linearity refers to the ability of an AM-Frequency Converter module to maintain a linear relationship between the amplitude and frequency changes of the output signal and the amplitude and frequency changes of the input signal during signal processing. Good AM-Frequency Converter linearity means the module can accurately adjust the amplitude and frequency according to changes in the input signal without introducing nonlinear distortion, thereby ensuring accurate and reliable signal processing.

[0063] For non-cooperative interference cancellation circuits, the non-cooperative interference portion in the received signal can be reduced or eliminated through interference cancellation.

[0064] Non-cooperative interference: "Non-cooperative" means that the interferer does not cooperate with or share any information with the receiving device. In other words, the interferer does not support the purpose of the receiving device and may be unknown, unpredictable, or intentionally transmitting an interfering signal.

[0065] Interference Cancellation: Cancellation is a technique designed to reduce or eliminate interference from the received signal, thereby improving signal quality and communication reliability. This technique typically involves using one or more auxiliary antennas to receive the interfering signal. Signal processing techniques are then used to generate a signal that is equal to but opposite in phase to the interfering signal. This signal, called the cancellation signal, is ideally canceled out when the cancellation signal is mixed with the original received signal.

[0066] It can be understood that the sub-band division circuit can receive radio frequency signals from an antenna (main antenna or auxiliary antenna). When a high-power interference signal is received, the sub-band division circuit can evenly divide the radio frequency receiving working frequency band into multiple sub-bands, and control the signal power in each sub-band within an appropriate range to avoid the components in the amplitude modulation and frequency conversion module (such as power amplifiers and mixers, etc.) from entering the nonlinear region. By designing the sub-band division circuit according to the intra-sub-band design indicators and inter-sub-band design indicators, it can be ensured that the intra-sub-band delay and attenuation flatness meet the design requirements, and that the inter-sub-band delay and attenuation consistency meet the design requirements, and the sub-band division circuit can be used to linearly process the received signal (including high-power interference signals and low-power useful signals).

[0067] By designing the AM / F conversion module and gain control module corresponding to each sub-band based on the AM / F conversion linearity index, the gain control module can be used to control the gain used for the AM processing of the AM / F conversion module according to the sub-band signal power, so that each device in the AM / F conversion module operates in the linear region and can linearly perform AM and frequency conversion processing on the sub-band signal.

[0068] Therefore, by controlling the signal power within each sub-band within an appropriate range and combining the linear design of the sub-band division circuit and the amplitude modulation and frequency conversion module, it is possible to provide high-power interference signals and low-power useful signals to the non-cooperative interference cancellation circuit without distortion. The RF signal channel has a large instantaneous dynamic range (a wide range of received signal power) and high linearity.

[0069] In one possible implementation, Figure 2 As shown, the sub-band division circuit includes: a low noise amplifier (LNA) 11, a power divider 12 and a plurality of sub-band filters 13, wherein the passband bandwidth of the sub-band filter 13 is equal to the bandwidth of a sub-band in the RF receiving working band;

[0070] The low noise amplifier 11 is used to amplify the received signal and output the amplified signal to the power divider 12;

[0071] The power divider 12 is used to evenly distribute the received signal to each sub-band filter 13 according to power;

[0072] The sub-band filter 13 is configured to perform channelization filtering on the received signal based on the passband bandwidth and output the filtered signal to the amplitude modulation and frequency conversion module 20 .

[0073] The LNA may receive a radio frequency signal from an antenna (main antenna or auxiliary antenna).

[0074] The main function of the LNA is to minimize the noise introduced by the amplifier itself and amplify the weak signal to a sufficient level for subsequent circuit processing while maintaining signal quality.

[0075] In one possible implementation, the design of the sub-band division circuit based on the intra-sub-band design index and the inter-sub-band design index includes:

[0076] Based on the intra-subband design indicators and inter-subband design indicators, by analyzing the simulated sub-band filter amplitude-frequency curve, sub-band filter phase-frequency curve and sub-band filter group delay curve, each sub-band filter is iteratively optimized to reduce the impact of the filter's non-ideal factors on interference cancellation, thereby achieving flatness of the intra-band indicators and consistency of the inter-band indicators.

[0077] Specifically, a single optimization process may include: analyzing the filter's amplitude-frequency curve and phase-frequency curve, which reflect the filter's response characteristics at different frequencies; evaluating the performance of the current filter design based on intra-subband design indicators, inter-subband design indicators, and these curves; and adjusting the filter parameters (e.g., changing the filter order, cutoff frequency, roll-off rate, etc.) based on the performance evaluation results to improve its performance. Iterative optimization may include multiple iterations of the above optimization process, enabling each subband filter to achieve optimal performance within its passband while ensuring performance consistency across subbands.

[0078] In a possible implementation, the method further includes:

[0079] After iteratively optimizing each sub-band filter, the frequency sweep signal is input to the sub-band division circuit;

[0080] Determining delay differences and attenuation differences between different sub-bands based on signals output by each sub-band filter;

[0081] Based on the delay and attenuation differences between different sub-bands, the compensation information corresponding to each sub-band (including phase compensation value and amplitude compensation value) is determined. The compensation information is used to instruct the non-cooperative interference cancellation circuit to perform phase compensation and amplitude compensation on the signal on the sub-band to achieve consistent optimization of the amplitude and phase characteristics.

[0082] A swept frequency signal is a signal whose frequency varies over time. To generate a swept frequency signal, you set sweep parameters, such as the start frequency, end frequency, and sweep rate. These parameters determine the frequency range and rate of change of the swept frequency signal. Based on the sweep parameters, you configure the signal generator and begin transmitting the swept frequency signal. The signal generator gradually changes the frequency of the signal according to the set parameters, forming a signal with a frequency that varies over time.

[0083] In one possible implementation, Figure 2 As shown, the amplitude modulation frequency conversion module 20 is composed of a mixer 21, a coupler 22, a signal amplitude modulation module 23, an intermediate frequency filter 24 and an analog-to-digital converter 25 connected in cascade order;

[0084] The gain control module 30 includes a detector 31 and a gain control calculation unit 32. The detector 31 is used to detect the coupled signal provided by the coupler 22 and convert the power of the coupled signal into a voltage signal. The gain control calculation unit 32 is used to output a gain control signal to the signal amplitude modulation module 23 based on the voltage signal.

[0085] The main function of a coupler is to extract a portion of the signal from the main signal path without disrupting it. In an AM / FM module, the coupler is used to extract a sample from the input signal as a coupled signal, which is then fed to the detector.

[0086] The mixer is the heart of the frequency conversion process, mixing the input signal with a signal generated by a local oscillator (LO). This produces two new frequency components: the sum frequency of the input signal and the LO frequency, and the difference frequency. Typically, the difference frequency is selected as the intermediate frequency (IF) signal for subsequent processing.

[0087] The IF filter selects a specific frequency range within the output signal of the AM / FM module and suppresses unwanted frequency components, including local oscillator leakage and other interfering signals. This ensures that only the desired signal components are passed to the next stage circuit.

[0088] The detector is used to detect the power of the sample signal extracted from the coupler and convert it into a voltage signal. This voltage signal reflects the power level of the signal.

[0089] The specific implementation of the amplitude modulation and frequency conversion module is described here. The signal undergoes frequency conversion through a mixer, down-converting the RF signal to within the ADC sampling rate range, allowing the signal to be transmitted over the required frequency band. The down-converted signal is then input into a coupler, which effectively distributes the signal to subsequent signal processing units. Next, the signal enters the signal amplitude modulation module, where the signal amplitude is adjusted according to the instructions of the gain control module. The signal output from the signal amplitude modulation module is then filtered by an intermediate frequency filter to remove unnecessary frequency components and ensure signal quality. Finally, an analog-to-digital converter converts the analog signal into a digital signal for subsequent digital signal processing (non-cooperative interference cancellation circuits are generally digital circuits).

[0090] This section describes the specific implementation of the gain control module, which consists of a detector and a gain control calculation unit. The detector detects the coupled signal provided by the coupler in real time and converts its power information into a voltage signal. This voltage signal reflects the power level of the current subband signal and provides a basis for gain control. The gain control calculation unit then calculates the appropriate gain control signal based on the voltage signal output by the detector and outputs it to the signal amplitude modulation module. This allows the AM processing gain of the AM / F conversion module to be adjusted in real time, ensuring efficient and stable signal processing.

[0091] In one possible implementation, the signal amplitude modulation module includes: at least one variable gain amplifier (VGA) and at least one power amplifier (PA);

[0092] Arrange the order of the variable gain amplifier and power amplifier based on the 1dB compression point of the power amplifier.

[0093] For a variable gain amplifier, its gain can be adjusted according to an external control signal and can be used to implement automatic gain control (AGC).

[0094] The 1dB compression point of an amplifier is the point at which its output power begins to deviate from linear growth as the input signal level increases. At this point, the rate of increase in the amplifier's output power begins to slow, meaning the amplifier begins to enter a nonlinear operating region, where the output power is no longer proportional to the input signal's increase.

[0095] The linearity of an amplifier can be determined by its 1dB compression point. When the input signal power reaches the amplifier's 1dB compression point, the output signal power decreases by 1dB. Therefore, a higher 1dB compression point indicates better linearity and the ability to handle larger input signals without distortion.

[0096] When arranging the VGA and power amplifier, it's usually best to place the VGA before the amplifier. The VGA's function is to automatically adjust the gain based on the input signal strength to maintain output signal stability. If the VGA is placed after the amplifier, when the amplifier's 1dB compression point is triggered, the VGA may not be able to adjust the input signal to the amplifier, resulting in signal distortion. Therefore, placing the VGA before the amplifier allows for signal conditioning and ensures linearity.

[0097] The present application also provides a radio frequency channel circuit, which is obtained by applying the above design method, such as Figure 2 As shown, the radio frequency channel circuit includes: a sub-band division circuit and an amplitude modulation and frequency conversion module and a gain control module corresponding to each sub-band;

[0098] The sub-band division circuit is used to evenly divide the radio frequency receiving working frequency band into multiple sub-bands;

[0099] The amplitude modulation and frequency conversion module is used to perform amplitude modulation and frequency conversion on the signal on the sub-band, and output the processed signal to the non-cooperative interference cancellation circuit;

[0100] The gain control module is used to control the gain used in the amplitude modulation processing of the amplitude modulation frequency conversion module based on the sub-band signal power, so that each device in the amplitude modulation frequency conversion module operates in the linear region.

[0101] In one possible implementation, the sub-band division circuit includes: a low noise amplifier, a power divider, and a plurality of sub-band filters, wherein the passband bandwidth of the sub-band filter is equal to the bandwidth of a sub-band in the RF receiving operating band;

[0102] The low noise amplifier is used to amplify the received signal and output the amplified signal to the power divider;

[0103] The power divider is used to evenly distribute the received signal to each sub-band filter according to power;

[0104] The sub-band filter is used to perform channelization filtering on the received signal (wideband interference) based on the passband bandwidth and output the filtered signal to the amplitude modulation and frequency conversion module.

[0105] In one possible implementation, a broadband filter is further provided between the low-noise amplifier and the power divider. The passband bandwidth of the broadband filter is equal to the bandwidth of the RF receiving operating band. The broadband filter is used to filter out out-of-band signals and provide the filtered receiving signal to the power divider.

[0106] In a possible implementation, the system further includes a signal compensation determination module, which is configured to:

[0107] Inputting a frequency sweep signal to a sub-band division circuit;

[0108] Determining delay differences and attenuation differences between different sub-bands based on signals output by each sub-band filter;

[0109] Based on the delay and attenuation differences between different sub-bands, the compensation information corresponding to each sub-band is determined. The compensation information is used to instruct the non-cooperative interference cancellation circuit to perform phase compensation and amplitude compensation on the signal on the sub-band to achieve consistent optimization of the amplitude and phase characteristics.

[0110] In a possible implementation, the amplitude modulation frequency conversion module is composed of a mixer, a coupler, a signal amplitude modulation module, an intermediate frequency filter and an analog-to-digital converter connected in cascade order;

[0111] The gain control module includes a detector and a gain control calculation unit. The detector is used to detect the coupled signal provided by the coupler and convert the power of the coupled signal into a voltage signal. The gain control calculation unit is used to output a gain control signal to the signal amplitude modulation module based on the voltage signal.

[0112] Figure 3 FIG. 1 is a schematic diagram of a radio frequency channel circuit provided in an embodiment of the present application applied to a multi-antenna array system. Figure 3As shown, a spatial angle difference between interference signals and communication signals can be created using an array system consisting of a main antenna and multiple auxiliary antennas. The multi-antenna array system includes an RF channel circuit corresponding to the main antenna and RF channel circuits corresponding to each of the N auxiliary antennas. The RF channel circuit can be designed using the aforementioned design approach. The analog-to-digital converter in the RF channel circuit converts analog signals into digital signals for subsequent processing by the digital processing module.

[0113] Each RF (receiving) channel circuit uses a sub-band division circuit to channelize broadband, high-power interference signals. Leveraging the frequency domain's "wide-to-narrow" approach, broadband interference is converted to narrowband interference for processing. A multi-channel, multi-sub-band gain control module controls the signal power within each sub-band within an appropriate range. Combined with the linearity design of the sub-band division circuit and the amplitude modulation and frequency conversion module, the non-cooperative interference cancellation circuit can simultaneously deliver high-power interference signals and low-power useful signals without distortion. This suppresses high-power broadband interference signals without damaging the useful signal, resulting in a wide instantaneous dynamic range and high linearity for the RF receiving channel.

[0114] It will be understood that the various numerical numbers involved in the embodiments of the present application are merely distinctions for the convenience of description and are not intended to limit the scope of the embodiments of the present application.

[0115] It is easy for those skilled in the art to understand that the above is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A non-cooperative interference cancellation radio frequency channel design method applied to a communication system, characterized in that: include: Determine the intra-subband design index, the inter-subband design index, and the amplitude modulation frequency conversion linearity index. The intra-subband design index is used to characterize the group delay flatness and attenuation flatness between different frequency points in the same subband. The inter-subband design index is used to characterize the group delay consistency and attenuation consistency between different subbands. The amplitude modulation frequency conversion linearity index is used to characterize the linearity of the amplitude modulation frequency conversion module during the signal processing process. Based on the intra-subband design index and the inter-subband design index, design a sub-band division circuit, wherein the sub-band division circuit is used to evenly divide the radio frequency receiving working frequency band into a plurality of sub-bands; Based on the AM / F conversion linearity index, design the AM / F conversion module and gain control module corresponding to each sub-band; Among them, the amplitude modulation and frequency conversion module is used to perform amplitude modulation and frequency conversion processing on the signal on the sub-band, and output the processed signal to the non-cooperative interference cancellation circuit; the gain control module is used to control the gain used for the amplitude modulation processing of the amplitude modulation and frequency conversion module based on the sub-band signal power, so that each device in the amplitude modulation and frequency conversion module operates in the linear region.

2. The non-cooperative interference cancellation radio frequency channel design method applied to a communication system according to claim 1, characterized in that: The sub-band division circuit includes: a low noise amplifier, a power divider and a plurality of sub-band filters, wherein the passband bandwidth of the sub-band filter is equal to the bandwidth of a sub-band in the radio frequency receiving working band; The low noise amplifier is used to amplify the received signal and output the amplified signal to the power splitter; The power divider is used to evenly distribute the received signal to each sub-band filter according to power; The sub-band filter is used to perform channelization filtering on the received signal based on the passband bandwidth and output the filtered signal to the amplitude modulation and frequency conversion module.

3. The non-cooperative interference cancellation radio frequency channel design method applied to a communication system according to claim 2, characterized in that: The designing of a sub-band division circuit based on the intra-sub-band design index and the inter-sub-band design index includes: Based on the intra-subband design indicators and inter-subband design indicators, each subband filter is iteratively optimized by analyzing the simulated subband filter amplitude-frequency curve, subband filter phase-frequency curve and subband filter group delay curve.

4. The non-cooperative interference cancellation radio frequency channel design method applied to a communication system according to claim 3, characterized in that: Also includes: After iteratively optimizing each sub-band filter, the frequency sweep signal is input to the sub-band division circuit; Determining delay differences and attenuation differences between different sub-bands based on signals output by each sub-band filter; Based on the delay differences and attenuation differences between different sub-bands, compensation information corresponding to each sub-band is determined, and the compensation information is used to instruct the non-cooperative interference cancellation circuit to perform phase compensation and amplitude compensation on the signal on the sub-band.

5. The non-cooperative interference cancellation radio frequency channel design method for a communication system according to any one of claims 1 to 4, characterized in that: The amplitude modulation frequency conversion module is composed of a mixer, a coupler, a signal amplitude modulation module, an intermediate frequency filter and an analog-to-digital converter in cascade connection in sequence; The gain control module includes a detector and a gain control calculation unit. The detector is used to detect the coupled signal provided by the coupler and convert the power of the coupled signal into a voltage signal. The gain control calculation unit is used to output a gain control signal to the signal amplitude modulation module based on the voltage signal.

6. A radio frequency channel circuit, characterized in that: The radio frequency channel circuit is obtained by applying the non-cooperative interference cancellation radio frequency channel design method applied to a communication system according to any one of claims 1 to 5, and the radio frequency channel circuit includes: a sub-band division circuit and an amplitude modulation and frequency conversion module and a gain control module corresponding to each sub-band; The sub-band division circuit is used to evenly divide the radio frequency receiving working frequency band into multiple sub-bands; The amplitude modulation and frequency conversion module is used to perform amplitude modulation and frequency conversion processing on the signal on the sub-band, and output the processed signal to the non-cooperative interference cancellation circuit; The gain control module is used to control the gain used in the amplitude modulation processing of the amplitude modulation and frequency conversion module based on the sub-band signal power, so that each device in the amplitude modulation and frequency conversion module operates in a linear region.

7. The radio frequency channel circuit according to claim 6, characterized in that: The sub-band division circuit includes: a low noise amplifier, a power divider and a plurality of sub-band filters, wherein the passband bandwidth of the sub-band filter is equal to the bandwidth of a sub-band in the radio frequency receiving working band; The low noise amplifier is used to amplify the received signal and output the amplified signal to the power splitter; The power divider is used to evenly distribute the received signal to each sub-band filter according to power; The sub-band filter is used to perform channelization filtering on the received signal based on the passband bandwidth and output the filtered signal to the amplitude modulation and frequency conversion module.

8. The radio frequency channel circuit according to claim 7, characterized in that: A broadband filter is also provided between the low noise amplifier and the power divider. The passband bandwidth of the broadband filter is equal to the bandwidth of the RF receiving working band. The broadband filter is used to filter out out-of-band signals and provide the filtered receiving signal to the power divider.

9. The radio frequency channel circuit according to claim 7, characterized in that: The module further includes a signal compensation determination module, wherein the signal compensation determination module is configured to: Inputting a frequency sweep signal to a sub-band division circuit; Determining delay differences and attenuation differences between different sub-bands based on signals output by each sub-band filter; Based on the delay differences and attenuation differences between different sub-bands, compensation information corresponding to each sub-band is determined, and the compensation information is used to instruct the non-cooperative interference cancellation circuit to perform phase compensation and amplitude compensation on the signal on the sub-band.

10. The radio frequency channel circuit according to any one of claims 6 to 9, characterized in that: The amplitude modulation frequency conversion module is composed of a mixer, a coupler, a signal amplitude modulation module, an intermediate frequency filter and an analog-to-digital converter in cascade connection in sequence; The gain control module includes a detector and a gain control calculation unit. The detector is used to detect the coupled signal provided by the coupler and convert the power of the coupled signal into a voltage signal. The gain control calculation unit is used to output a gain control signal to the signal amplitude modulation module based on the voltage signal.

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