An apparatus and method for wideband signal channelization reception and high-precision reconstruction.

Abstract

This application provides a method and apparatus for channelized reception and high-precision reconstruction of broadband signals, belonging to the field of broadband signal processing technology in wireless communication. The method includes: a pre-selection filtering module performing first-level channel division on the broadband radio frequency signal; a receiving frequency conversion module down-converting the narrowband radio frequency signal to an intermediate frequency (IF), suppressing image frequencies using an IF filter; a digital channelization module down-converting the digital IF signal to baseband, implementing second-level channel division using a baseband digital channelization low-pass filter to obtain narrowband sub-signals; a high-precision reconstruction module synthesizing a broadband signal through up-conversion and interpolation filtering to obtain the reconstructed signal; a playback calibration module calculating the initial phase difference of the calibration signal between different channels for phase compensation to obtain the phase-calibrated reconstructed signal; and up-converting the phase-calibrated reconstructed signal back to radio frequency and sending it back to the frequency-hopping communication system. This application improves the accuracy and engineering reliability of the channelized reception and reconstruction design method.

Description

Technical Field

[0001] This application belongs to the field of wireless communication broadband signal processing technology, and more specifically, relates to an apparatus and method for broadband signal channelization reception and high-precision reconstruction. Background Technology

[0002] Wireless communication is a crucial means of communication. Complex electromagnetic environments and malicious human interference pose significant challenges to wireless communication. In increasingly complex electromagnetic environments, frequency-hopping communication technology has proven to be an effective method for anti-interference communication, providing frequency diversity and interference diversity, effectively improving the transmission quality of wireless links and reducing interference. However, with the development of frequency-hopping communication, the receiving bandwidth of a communication system receiver typically contains multiple signals with different bandwidths and arbitrary frequency hopping locations. Furthermore, the states of these signals, such as bandwidth, location, and number, often change during reception. Therefore, improving the data processing performance and efficiency of broadband receiving systems is an urgent research issue.

[0003] Channelization reception and reconstruction is a crucial technology applied in broadband receiving systems. Its basic idea is to divide the operating bandwidth into several narrower sub-bands using an analytical filter bank, perform corresponding signal processing within each narrow-band channel, and finally reconstruct the broadband signal from the sub-signals using a synthesis filter bank. However, in practical engineering applications, commonly used digital channelization techniques suffer from slow processing speeds due to high filter orders and issues such as "dimples" and "bumps" appearing in the overlapping regions of the spectrum after channelization, posing significant challenges to engineering projects and the reconstruction accuracy after channelization. Furthermore, the operating bandwidth of frequency-hopping communication typically exceeds 200MHz; processing the entire received operating bandwidth using digital channelization would significantly increase the resource consumption in the FPGA. Therefore, with the increasing speed of wireless communication, broadband communication systems have an urgent need to improve communication capacity and signal processing speed. Traditional multi-channel channelization methods based on independent digital down-conversion technology are computationally expensive and require substantial hardware resources. Summary of the Invention

[0004] In view of the shortcomings of the prior art, the purpose of this application is to provide a method and apparatus for channelized reception and high-precision reconstruction of broadband signals, aiming to solve the engineering problems of broadband signal reception, reconstruction and data processing.

[0005] To achieve the above objectives, this application provides a device for broadband signal channelization reception and high-precision reconstruction, comprising: an antenna front-end module, a pre-selection filtering module, a receive frequency conversion module, a digital decimation filtering module, a digital channelization module, a high-precision reconstruction module, and a playback calibration module connected in sequence; the output of the playback calibration module is connected to the high-precision reconstruction module, a frequency hopping communication system, and the antenna front-end module.

[0006] The antenna front-end module is used to limit and amplify broadband radio frequency signals and couple calibration signals, which are then sent to the pre-selection filtering module via power divider and multiplexer.

[0007] The pre-selection filtering module is used to perform the first-level channel division of broadband radio frequency signals through a pre-selection filter bank, thereby realizing the conversion of broadband radio frequency signals to narrowband radio frequency signals;

[0008] The receiver frequency converter module is used to downconvert each narrowband radio frequency signal to an intermediate frequency.

[0009] The digital decimation and filtering module is used to decimate and filter the intermediate frequency narrowband radio frequency signal converted into a digital signal in order to reduce the data rate and filter out the high-order harmonic components sampled and decimated.

[0010] The digital channelization module is used to perform a second-level channel division on each digital signal transmitted by the digital decimation and filtering module to obtain the narrowband sub-signal of each channel.

[0011] The high-precision reconstruction module is used to synthesize the narrowband sub-signals of each channel to obtain the reconstructed signal of the original working bandwidth;

[0012] The playback calibration module generates a calibration signal that is transmitted to the antenna front-end module. It also calculates the initial phase difference of the calibration signal between different channels, obtains the calibration coefficients, and transmits them to the high-precision reconstruction module to perform phase compensation on the channel, thereby obtaining the phase-calibrated reconstructed signal. The phase-calibrated reconstructed signal is then up-converted to an RF signal and sent back to the frequency hopping communication system.

[0013] More preferably, the receiving frequency conversion module includes a local oscillator unit, a mixer, and an intermediate frequency (IF) filter; the input of the mixer is connected to a pre-selection filter and the local oscillator unit, and the output is connected to the input of the IF filter; the output of the IF filter is connected to a digital decimation filter module; the local oscillator unit is used to generate the local oscillator signal required for each channel's narrowband RF signal; the mixer is used to mix the narrowband RF signal of each channel with the corresponding local oscillator signals of different frequencies, shifting the spectrum of the narrowband RF signal to the same IF; the IF filter is used to filter out the image signal and spurious signal after mixing, while suppressing out-of-band signals.

[0014] More preferably, the decimation filtering module includes an analog-to-digital conversion unit, a digital decimation unit, and a digital low-pass filter connected in sequence.

[0015] The analog-to-digital conversion unit is used to perform bandpass sampling on the intermediate frequency narrowband radio frequency signal to obtain the narrowband digital signal; the digital decimation unit is used to decimate the narrowband digital signal to reduce the data rate; the digital low-pass filter is used to filter out the high-order harmonic components generated by sampling and decimation of the narrowband digital signal.

[0016] More preferably, the digital channelization module includes a digital down-conversion unit and a channel partitioning filter; the input of the digital down-conversion unit is connected to the decimation filter module, and the output is connected to the channel partitioning filter; the digital down-conversion unit is used to shift the different channel signals transmitted by the digital low-pass filter to the baseband spectrum; the channel partitioning filter is used to partition the different channel signals in the baseband to obtain the narrowband sub-signal of each channel.

[0017] More preferably, the high-precision reconstruction module includes an interpolation operation unit, a low-pass filter, a digital up-conversion unit, and a synthesizer connected in sequence;

[0018] The interpolation unit is used to increase the sampling rate of the frequency band signals of each channel transmitted by the channel division filter; the low-pass filter is used to filter out spurious signals introduced by the shift of the signal frequency band after interpolation and obtain the baseband signal; the digital up-conversion unit is used to up-convert the baseband signal of each channel and shift the frequency band to the frequency band position of the broadband intermediate frequency signal; the synthesizer is used to synthesize and add the signals of each channel transmitted by the digital up-conversion unit to restore the bandwidth of the operating frequency band of the frequency hopping communication system and output it to the playback calibration module.

[0019] More preferably, the playback calibration module includes a calibration signal generation unit, an adjacent channel phase difference calculation unit, a calibration coefficient unit, and a playback unit;

[0020] The output of the calibration signal generation unit is connected to the antenna front-end module; the input of the adjacent channel phase difference calculation unit is connected to the high-precision reconstruction module, and its output is connected to the input of the calibration coefficient unit; the output of the calibration coefficient unit is connected to the high-precision reconstruction module; the input of the playback unit is connected to the output of the high-precision reconstruction module, and its output is connected to the frequency hopping communication system.

[0021] The calibration signal generation unit generates calibration signals at the frequency points where adjacent channels overlap, which are then input to the antenna front-end module. These calibration signals are coupled with the broadband RF signal into the link. The adjacent channel phase difference calculation unit calculates the phase difference between two adjacent channels based on the phase of the calibration signal in each channel. The calibration coefficient unit substitutes the phase difference between adjacent channels into the calibration coefficient calculation formula to obtain the calibration coefficient. Before upconversion, one channel is used as the phase reference to compensate the other channel for phase. The playback unit upconverts the calibrated reconstructed signal to RF and sends it back to the frequency hopping communication system via a DAC.

[0022] On the other hand, this application provides a method for channelized reception and high-precision reconstruction of broadband signals, comprising the following steps:

[0023] Step S1: After the broadband radio frequency signal is amplified by limiting, the calibration signal is coupled and transmitted to the pre-selected filtering module via power divider and multiplexer.

[0024] Step S2: Perform first-level channel partitioning on the broadband radio frequency signal to convert it into a narrowband radio frequency signal;

[0025] Step S3: After downconverting each narrowband RF signal to intermediate frequency, perform analog-to-digital conversion, decimation, and filtering to reduce the data rate and filter out the high-order harmonic components of the sampled signal.

[0026] Step S4: Perform a second-level channel division on each digital signal obtained in step S3 to obtain the narrowband sub-signal of each channel;

[0027] Step S5: Synthesize the narrowband sub-signals of each channel in step S4 to obtain the reconstructed signal of the original working bandwidth;

[0028] Step S6: Calculate the initial phase difference of the calibration signal between different channels, obtain the calibration coefficients to perform phase compensation on the channels, and then obtain the reconstructed signal after phase calibration;

[0029] Step S7: Upconvert the reconstructed signal after phase calibration to an RF signal and send it back to the frequency hopping communication system.

[0030] More preferably, step S3 specifically includes the following steps:

[0031] Step S3.1: Obtain the local oscillator signal required for each narrowband RF signal. The isolation between each local oscillator signal is required to be higher than the preset isolation threshold. At the same time, each local oscillator signal is required to have a common crystal oscillator reference to ensure the amplitude and phase consistency of the local oscillator signal after phase-locked loop frequency multiplication.

[0032] Step S3.2: Mix each narrowband RF signal with local oscillator signals of different frequencies, downconvert each narrowband RF signal to the same intermediate frequency signal, and then filter out the image frequency through intermediate frequency filtering;

[0033] Step S3.3: Bandpass sample the intermediate frequency narrowband radio frequency signal to obtain the narrowband digital signal after spectrum shifting;

[0034] Step S3.4: Perform digital decimation on the narrowband digital signal after spectrum shifting in step S3.3 to reduce the data rate, and then filter the decimated narrowband digital signal to remove high-order harmonic components.

[0035] More preferably, step S4 specifically includes the following steps:

[0036] Step S4.1: Use digital downconversion to mix the narrowband digital signal of each channel obtained in step S3 with local oscillator signals of different frequencies, and shift the narrowband digital signal obtained in step S3 to the baseband for channelization processing.

[0037] Step S4.2: The baseband sub-signals of each channel are processed by channel division filtering. On the one hand, the image signal after down-conversion is filtered out, and on the other hand, the baseband is uniformly digitally channelized to obtain narrowband sub-signals of multiple channels.

[0038] More preferably, step S5 specifically includes the following steps:

[0039] Step S5.1: Perform polyphase interpolation and low-pass filtering on the narrowband sub-signals of each channel to restore the broadband radio frequency signal data rate and filter out the harmonic components caused by interpolation;

[0040] Step S5.2: Upconvert the interpolated and filtered baseband signal and the local oscillator signals of different frequencies, and then send them together into the synthesizer to splice them to obtain the reconstructed signal of the original working bandwidth.

[0041] More preferably, step S6 specifically includes the following steps:

[0042] Step S6.1: Couple the generated calibration signal and the received broadband radio frequency signal into the link; wherein, the frequency of the calibration signal is the center frequency of the overlapping area of ​​adjacent channel frequency bands;

[0043] Step S6.2: Calculate the phase difference of the calibration signal between adjacent channels;

[0044] Step S6.3: Substitute the phase difference into the calibration coefficient calculation formula to obtain the calibration coefficient, perform phase compensation on the channel, and obtain the reconstructed signal after phase calibration;

[0045] Step S6.4: Upconvert the reconstructed signal after phase calibration to an RF signal, and transmit it to the frequency hopping communication system through digital-to-analog conversion.

[0046] Overall, the technical solutions conceived in this application have the following beneficial effects compared with the prior art:

[0047] This application provides a method for channelized reception and high-precision reconstruction of broadband signals. By combining radio frequency circuits with digital signal processing, a two-stage channelization of broadband signals is achieved. Based on traditional digital channel processing, the advantages of easy channelization engineering, good filtering effect and strong robustness of radio frequency conditioning circuits are utilized to improve the engineering feasibility and reliability of the channelization reception and reconstruction design scheme.

[0048] This application provides a method for channelized reception and high-precision reconstruction of broadband signals. The operating bandwidth of the original broadband signal is divided into multiple radio frequency sub-signals by radio frequency pre-selection filtering. Then, each sub-signal is digitally channelized in the baseband by analog and digital down-conversion to obtain multiple narrowband channels. A channel partitioning filter is used to achieve passband flatness and stopband attenuation characteristics, while requiring the filter band design to meet the principle of complementary amplitude of adjacent channels, thereby ensuring high-precision reconstruction.

[0049] In engineering practice, it has been found that the start-up time of the analog local oscillator and the digital NCO is uncertain, which will lead to an initial phase difference between channels. This application proposes a phase calibration method. The playback calibration module generates a single-tone calibration signal and couples it into the entire link with the broadband received signal. It calculates the phase difference of the calibration signal in the two channels and obtains the calibration coefficient as phase compensation between channels, thus eliminating the phase mismatch of spectrum splicing in the overlapping area. Attached Figure Description

[0050] Figure 1 This is a schematic block diagram of the broadband signal channelization reception and high-precision reconstruction device provided in the embodiments of this application;

[0051] Figure 2 This is a circuit block diagram of the antenna front-end module provided in an embodiment of this application;

[0052] Figure 3 This is a circuit block diagram of the radio frequency signal conditioning unit provided in the embodiments of this application;

[0053] Figure 4 This is a block diagram of the digital decimation filtering module provided in an embodiment of this application;

[0054] Figure 5 This is a block diagram illustrating the principle of digital channelization provided in an embodiment of this application;

[0055] Figure 6 This is a block diagram illustrating the principle of the high-precision reconstruction module provided in this application embodiment;

[0056] Figure 7 This is a structural diagram of the phase calibration method provided in the embodiments of this application;

[0057] Figure 8 These are the effect diagrams of broadband noise spectrum reconstruction without calibration and broadband white noise spectrum reconstruction after amplitude and phase calibration provided in the embodiments of this application after the broadband white noise signal is injected into the experimental spectrum. Detailed Implementation

[0058] The embodiments of this application are described below with reference to the accompanying drawings.

[0059] This application provides a device for channelized reception and high-precision reconstruction of broadband signals. It adopts a two-stage channelization combining a radio frequency signal conditioning unit and a digital signal processing unit. Through a receiving antenna, an antenna front-end module, a pre-selection filter circuit, a digital channel division filter, a digital interpolation filter module, a signal reconstruction module, a DAC playback module, and a phase calibration module, the broadband signal is first divided into multiple narrowband channels for signal reception and processing. Then, the narrowband signals of each channel are reconstructed and sent back to the frequency hopping communication system. The calibration module is used to realize phase compensation between different channels, thus building a complete process architecture for channelized reception and reconstruction of broadband signals.

[0060] More specifically, this application addresses frequency-hopping communication systems by constructing a framework for wideband signal channelization reception and high-precision reconstruction that combines radio frequency circuits with digital processing. It solves the engineering challenges of two-stage channelization reception of wideband signals and achieves high-precision reconstruction. Targeting the characteristics of wide operating bandwidth and high hopping speed in frequency-hopping communication signals, the first-stage channelization of the wideband radio frequency signal is achieved through pre-selective filtering in the radio frequency circuit. Then, the signal is down-converted to an intermediate frequency (IF) signal using analog circuitry, reducing the sampling rate of digital processing. Next, the signal undergoes ADC sampling and digital decimation filtering to further reduce the digital signal processing rate. The signal is then input into a digital channelization module, where it is further divided into multiple parallel narrowband signals using digital down-conversion and channel partitioning filters, completing the second-stage channelization of the digital baseband signal. Finally, high-precision reconstruction completes the spectral stitching of each channel's narrowband signal back to the original operating frequency band, and a calibration signal is used to compensate for the initial phase difference between different channels. This wideband signal channelization reception and high-precision reconstruction device effectively solves the engineering challenges of wideband signal reception, reconstruction, and data processing without affecting the frequency and performance of frequency-hopping communication.

[0061] like Figure 1 As shown, the broadband signal channelization reception and high-precision reconstruction device includes an antenna front-end module 00, a pre-selection filtering module 01, a receive frequency conversion module 02, a digital decimation filtering module 03, a digital channelization module 04, a high-precision reconstruction module 05, and a playback calibration module 06.

[0062] The antenna front-end module 00 has its input terminal connected to the receiving antenna and the playback calibration module, and its output terminal connected to the RF signal conditioning circuit. The receiving antenna is used to receive broadband RF signals. The playback calibration module outputs a calibration signal. The antenna front-end module is used to perform amplitude limiting and amplification of the broadband RF signal, couple the calibration signal, and send it to the RF pre-selection filter module via power splitting.

[0063] The input of the pre-selection filtering module 01 is connected to the antenna front-end module 00, and the output is connected to the receiving frequency conversion module 02. The pre-selection filtering module 01 is used to perform the first-level channel division of broadband radio frequency signals in the analog circuit, so as to realize the conversion of broadband radio frequency signals to narrowband radio frequency signals.

[0064] The input of the receiving frequency conversion module 02 is connected to the pre-selection filter module 01, and the output is connected to the decimation filter module 03 of the digital signal processing unit through the ADC analog-to-digital converter. The receiving frequency conversion module 02 is used to downconvert each narrowband RF signal to intermediate frequency, reducing the requirements for A / D sampling rate.

[0065] The input of the digital decimation and filtering module 03 is connected to the receiving frequency conversion module 02 of the radio frequency signal conditioning unit via an ADC, and the output is connected to the digital channelization module 04. The digital decimation and filtering module 03 is used for decimation and filtering of digital signals, reducing the data rate, increasing the digital signal processing speed, and filtering out high-order harmonic components from the sampling and decimation.

[0066] The digital channelization module 04 is connected to the digital decimation and filtering module 03 at its input end and to the high-precision reconstruction module 05 of the signal playback unit at its output end. The digital channelization module 04 is used for the second-level channel division of each sub-signal in the digital signal processing section.

[0067] The high-precision reconstruction module 05 is connected at its input to the digital channelization module 04 of the digital signal processing unit and the playback calibration module 06 of the signal playback unit, and at its output to the playback calibration module 06. The high-precision reconstruction module 05 is used to synthesize the sub-signals of each channel to obtain the reconstructed signal of the original working bandwidth.

[0068] The playback calibration module 06 is connected to the high-precision reconstruction module 05 at its input end and to the frequency hopping communication system and the antenna front-end module 00 at its output end. The playback calibration module 06 is used to reconstruct the signal by upconverting it to an RF signal and sending it back to the frequency hopping communication system via a DAC. On the other hand, it generates a calibration signal and sends it to the antenna front-end module 00, and calculates the initial phase difference of the calibration signal between different channels to obtain the calibration coefficient.

[0069] The circuit block diagram of antenna front-end module 00 is as follows: Figure 2 As shown, it includes: a limiter 001, a low-noise amplifier 002, a coupler 003, and a power divider 004; the limiter 001 limits the spatial signal received by the antenna to signals above 0dBm, preventing large signal inputs from damaging back-end equipment; the low-noise amplifier 002 amplifies low-power input signals to -10dBm to meet subsequent data processing requirements; the coupler 003 couples the calibration signal into the broadband radio frequency signal; the power divider 004 splits the coupled signal into multiple inputs to the pre-selection filter of each channel;

[0070] More specifically, the specific execution steps of the antenna front-end module 00 are as follows:

[0071] Step S01: The antenna receives a broadband radio frequency signal and inputs it to the limiter 001 to limit the input signal power. If the received signal power is large, the limiter starts to work and reflects the high-power signal. The reflected signal is absorbed by the load through a 90° bridge. If the received power is a small signal, the limiter does not work and the signal is amplified by the low-noise amplifier 002 to make the signal power meet the processing requirements.

[0072] Step S02: The broadband radio frequency signal and the calibration signal, after being limited and amplified, enter the coupler 003 together to obtain the coupled signal, which is then split into multiple signals by the power divider;

[0073] The circuit block diagram of the radio frequency signal conditioning unit is as follows: Figure 3 As shown, it includes: a pre-selection filter 01 and a receiving frequency conversion module 02; the receiving frequency conversion module 02 includes a local oscillator unit 021, a mixer 022, and an intermediate frequency filter 023; the pre-selection filter 01 performs bandpass processing on the broadband RF signal of each channel to obtain narrowband signals of different frequency bands, and suppresses out-of-band noise and interference, requiring that the passband design of each channel's pre-selection filter overlaps to prevent signal loss; the local oscillator unit 021 generates the local oscillator signal required for the narrowband RF signal of each channel, requiring that the local oscillator signals of different frequencies share a common crystal reference and have high isolation; the mixer 022 mixes the narrowband RF signal of each channel with the corresponding local oscillator signals of different frequencies, shifting the spectrum to the same intermediate frequency; the intermediate frequency filter 013 filters out the image signal and spurious signals after mixing, and further suppresses out-of-band signals;

[0074] More specifically, each signal is passed through the corresponding pre-selection filter 01 to obtain different narrowband frequency band sub-signals. The passband range of each pre-selection filter is set by the communication system, requiring that the passbands of the pre-selection filters of adjacent channels have overlapping areas.

[0075] More preferably, the execution steps of the receiving frequency converter module 02 are as follows:

[0076] Step S21: Use local oscillator unit 021 to generate the local oscillator signal required for each narrowband sub-signal. High isolation is required between each local oscillator signal to prevent crosstalk. At the same time, each local oscillator signal is required to have a common crystal reference to ensure the amplitude and phase consistency of the local oscillator signal after phase-locked loop frequency multiplication.

[0077] Step S22: Each sub-signal is mixed with local oscillator signals of different frequencies 022, and the radio frequency signals are down-converted to the same intermediate frequency signal, and then filtered out by intermediate frequency filtering 023 to remove the image frequency.

[0078] The principle block diagram of the extraction filter module 03 is as follows: Figure 4As shown, it includes an analog-to-digital conversion unit 031, a digital decimation unit 032, and a digital low-pass filter 033; the analog-to-digital conversion unit 031 performs bandpass sampling on the intermediate frequency analog signal to obtain a digital signal; the digital decimation unit 032 is used to decimate the digital signal to reduce the data rate; the digital low-pass filter 033 is used to filter out the high-order harmonic components generated by sampling and decimation.

[0079] More specifically, the extraction filter module 03 performs the following steps:

[0080] Step S31: Use analog-to-digital converter unit 031 to perform bandpass sampling on the intermediate frequency analog signal to obtain the narrowband digital signal after spectrum shifting;

[0081] Step S32: Digitally decimate the sampled signal by 0.32 to reduce the data rate;

[0082] Step S33: The narrowband digital signal after sampling is filtered by digital low-pass filter 033 to remove high-order harmonic components and is then divided into multiple signals and sent to the digital channelization module.

[0083] The principle block diagram of digital channelization module 04 is as follows: Figure 5 As shown, it includes a digital down-conversion unit 041 and a channel partitioning filter 042; the digital down-conversion unit 041 is used to shift the spectrum of signals from different channels to the baseband; the channel partitioning filter is used to partition the signals of different channels in the baseband to obtain narrower sub-signals.

[0084] More specifically, the digital channelization method includes the following steps:

[0085] Step S41: Use digital downconversion 041 to mix the digital signal of each channel with the local oscillator signal of different frequencies, and move the digital signal to the baseband for channelization processing;

[0086] Step S42: The baseband sub-signal of each channel is passed through channel division filter 042. On the one hand, the image signal after down-conversion is filtered out, and on the other hand, the baseband is uniformly digitally channelized to obtain narrowband sub-signals of multiple channels.

[0087] The principle block diagram of the high-precision reconstruction module 05 is as follows: Figure 6As shown, the system includes an interpolation unit 051, a low-pass filter 052, a digital up-conversion unit 053, and a synthesizer 054. The interpolation unit 051 increases the sampling rate of the frequency band signals of each channel to ensure that the combined RF signals can effectively distinguish signals at each frequency point. The low-pass filter 052 is used to filter out spurious signals caused by the shift of the frequency band of the interpolated signal, retaining the baseband signal. The digital up-conversion unit 053 is used to up-convert the frequency band signal of each channel, shifting the frequency band to the original signal's frequency band position. The synthesizer 054 is used to combine and add the signals of each channel in each path, restoring the bandwidth of the operating frequency band of the frequency hopping communication system for output, which is then output to the playback calibration module.

[0088] More specifically, the high-precision reconstruction method 05 includes the following steps:

[0089] Step S51: Perform polyphase interpolation and low-pass filtering on the narrowband sub-signals of each channel to restore the original data rate and filter out the harmonic components caused by interpolation.

[0090] Step S52: Upconvert the narrowband signal after interpolation and filtering with local oscillator signals of different frequencies, and then send them together to synthesizer 054 to splice them to obtain the reconstructed signal of the original working bandwidth.

[0091] The principle block diagram of playback calibration module 06 is as follows: Figure 7 As shown, the system includes a calibration signal generation unit 061 for overlapping channel frequencies, an adjacent channel phase difference calculation unit 062, a calibration coefficient unit 063, and a playback unit 064. The calibration signal generation unit 061 generates a single-tone signal at the overlapping frequency of adjacent channels, inputs it to the antenna front-end module, couples it with the broadband RF signal, and enters the link. The adjacent channel phase difference calculation unit 062 obtains the phase of the calibration signal obtained after upconversion in the high-precision reconstruction module 05 in two adjacent channels, calculates the phase difference between them, and obtains the phase difference between the two channels due to the uncertainty of the start-up time of the analog local oscillator and the digital NCO. The calibration coefficient unit 063 substitutes the phase difference of the adjacent channels into the calibration coefficient calculation formula to obtain the calibration coefficient. Before upconversion, it uses one channel as the phase reference to perform phase compensation on the other channel. The playback unit 064 upconverts the calibrated reconstructed signal to RF and sends it back to the frequency hopping communication system through a DAC.

[0092] More specifically, the playback calibration module 06 includes the following steps:

[0093] Step S61: A calibration signal is generated using calibration signal unit 061. The frequency of the calibration signal is the center frequency of the overlapping area of ​​adjacent channel frequency bands. The signal is input to the antenna front-end module and coupled with the received RF broadband signal to enter the link. The calibration signal includes single-tone signals of different frequencies. The single-tone signals of different frequencies are transmitted sequentially.

[0094] Step S62: Calculate the phase difference between adjacent channels for a single-tone signal at a given frequency;

[0095] Step S63: Substitute the phase difference into the calibration coefficient calculation formula to obtain the calibration coefficient, and input it into the high-precision reconstruction module to perform phase compensation on the channel;

[0096] Step S64: The reconstructed signal after phase calibration is sent to the playback unit, up-converted to RF signal, digital-to-analog conversion is achieved through DAC, and output to the frequency hopping communication system.

[0097] Figure 8 The reconstructed spectrum of the broadband white noise signal injection experiment was used to verify the signal reconstruction effect of the channelization and high-precision device. The frequency components of the white noise signal have the same energy density and the amplitude is flat throughout the power spectrum, which makes it easy to observe the spectrum splicing effect of the signal reconstruction. Therefore, the signal source generates broadband white noise and injects it into the receiving antenna for channelization and reconstruction. By comparison, it was found that the spectrum reconstruction effect of the uncalibrated broadband noise is "concave", but the spectrum reconstruction effect of the broadband white noise after amplitude and phase calibration shows that the power spectrum amplitude of the reconstructed signal is flat, indicating the feasibility of the channelization reception and high-precision reconstruction method, and verifying the engineering feasibility of the device developed in this invention.

[0098] It should be understood that expressions such as “comprising” and “may include” used in this application indicate the existence of the disclosed functions, operations or constituent elements, and do not limit one or more additional functions, operations and constituent elements.

[0099] In the description of the embodiments of this application, it should be noted that, unless otherwise expressly specified and limited, the term "connection" should be interpreted broadly.

[0100] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A device for broadband signal channelization reception and high-precision reconstruction, characterized in that, include: The antenna front-end module, pre-selection filter module, receive frequency conversion module, digital decimation filter module, digital channelization module, high-precision reconstruction module, and playback calibration module are connected in sequence. The output of the playback calibration module is connected to the high-precision reconstruction module, the frequency hopping communication system, and the antenna front-end module. The antenna front-end module is used to limit and amplify broadband radio frequency signals and couple calibration signals, which are then sent to the pre-selection filtering module via power divider and multiplexer. The pre-selection filtering module is used to perform the first-level channel division of broadband radio frequency signals through a pre-selection filter bank, thereby realizing the conversion of broadband radio frequency signals to narrowband radio frequency signals; The receiver frequency converter module is used to downconvert each narrowband radio frequency signal to an intermediate frequency. The digital decimation and filtering module is used to decimate and filter the intermediate frequency narrowband radio frequency signal converted into a digital signal in order to reduce the data rate and filter out the high-order harmonic components sampled and decimated. The digital channelization module is used to perform a second-level channel division on each digital signal transmitted by the digital decimation and filtering module to obtain the narrowband sub-signal of each channel. The high-precision reconstruction module is used to synthesize the narrowband sub-signals of each channel to obtain the reconstructed signal of the original working bandwidth; The playback calibration module generates a calibration signal that is transmitted to the antenna front-end module. It also calculates the initial phase difference of the calibration signal between different channels, obtains the calibration coefficients, and transmits them to the high-precision reconstruction module to perform phase compensation on the channel, thus obtaining the phase-calibrated reconstructed signal. The phase-calibrated reconstructed signal is then up-converted to an RF signal and sent back to the frequency hopping communication system. The receiving frequency conversion module includes a local oscillator unit, a mixer, and an intermediate frequency filter; The input of the mixer is connected to the preselection filter and the local oscillator unit, and the output is connected to the input of the intermediate frequency filter. The output of the intermediate frequency filter is connected to the digital decimation filter module; The local oscillator unit is used to generate the local oscillator signal required for each channel's narrowband RF signal; the mixer is used to mix the narrowband RF signal of each channel with the corresponding local oscillator signal of different frequencies, shifting the spectrum of the narrowband RF signal to the same intermediate frequency. Intermediate frequency (IF) filters are used to remove image signals and spurious signals after mixing, while suppressing out-of-band signals. The decimation filtering module includes an analog-to-digital converter, a digital decimation unit, and a digital low-pass filter connected in sequence. The analog-to-digital converter is used to perform bandpass sampling on intermediate frequency narrowband radio frequency signals to obtain narrowband digital signals; The digital decimation unit is used to decimate narrowband digital signals to reduce the data rate; Digital low-pass filters are used to filter out high-order harmonic components in narrowband digital signals caused by sampling and decimation.

2. The apparatus according to claim 1, characterized in that, The digital channelization module includes a digital downconversion unit and a channel partitioning filter. The input of the digital downconversion unit is connected to the decimation filter module, and the output is connected to the channel partitioning filter. The digital downconversion unit is used to shift the different channel signals transmitted by the digital low-pass filter to the baseband spectrum. The signal partitioning filter is used to partition the different channel signals in the baseband to obtain a narrower sub-signal for each channel.

3. The apparatus according to claim 2, characterized in that, The high-precision reconstruction module includes an interpolation operation unit, a low-pass filter, a digital up-conversion unit, and a synthesizer connected in sequence. The interpolation unit is used to increase the sampling rate of the frequency band signals of each channel transmitted by the channel division filter; Low-pass filters are used to filter out spurious signals introduced by the shift in the frequency band of the interpolated signal and obtain the baseband signal; The digital upconversion unit is used to upconvert the baseband signal of each channel and shift the frequency band to the frequency band position of the broadband intermediate frequency signal. The synthesizer is used to combine and add the individual channel signals transmitted by the digital up-conversion unit to restore the bandwidth of the frequency hopping communication system's operating frequency band and output it to the playback calibration module.

4. The apparatus according to claim 1 or 3, characterized in that, The playback calibration module includes a calibration signal generation unit, an adjacent channel phase difference calculation unit, a calibration coefficient unit, and a playback unit; The output of the calibration signal generation unit is connected to the antenna front-end module; the input of the adjacent channel phase difference calculation unit is connected to the high-precision reconstruction module, and its output is connected to the input of the calibration coefficient unit; the output of the calibration coefficient unit is connected to the high-precision reconstruction module; the input of the playback unit is connected to the output of the high-precision reconstruction module, and its output is connected to the frequency hopping communication system. The calibration signal generation unit is used to generate calibration signals at the frequency points where adjacent channels overlap, which are input to the antenna front-end module. The calibration signals are coupled into the link with the broadband radio frequency signals. The adjacent channel phase difference calculation unit is used to calculate the phase difference between two adjacent channels by using the phase of the calibration signal in two adjacent channels; The calibration coefficient unit is used to substitute the phase difference between adjacent channels into the calibration coefficient calculation formula to obtain the calibration coefficient, which is then transmitted to the high-precision reconstruction module. Before upconversion, one channel is used as the phase reference to perform phase compensation on the other channel. The playback unit is used to upconvert the calibrated reconstructed signal to radio frequency and send it back to the frequency hopping communication system via DAC.

5. A method based on the apparatus of claim 1, characterized in that, Includes the following steps: Step S1: After the broadband radio frequency signal is amplified by limiting, the calibration signal is coupled and transmitted to the pre-selected filtering module via power divider and multiplexer. Step S2: Perform first-level channel partitioning on the broadband radio frequency signal to convert it into a narrowband radio frequency signal; Step S3: After downconverting each narrowband RF signal to intermediate frequency, perform analog-to-digital conversion, decimation, and filtering to reduce the data rate and filter out the high-order harmonic components of the sampled signal. Step S4: Perform a second-level channel division on each digital signal obtained in step S3 to obtain the narrowband sub-signal of each channel; Step S5: Synthesize the narrowband sub-signals of each channel in step S4 to obtain the reconstructed signal of the original working bandwidth; Step S6: Calculate the initial phase difference of the calibration signal between different channels, obtain the calibration coefficient, perform phase compensation on the channel, and then obtain the reconstructed signal after phase calibration; Step S7: Upconvert the reconstructed signal after phase calibration to an RF signal and send it back to the frequency hopping communication system.

6. The method according to claim 5, characterized in that, Step S3 specifically includes the following steps: Step S3.1: Obtain the local oscillator signal required for each narrowband RF signal. The isolation between each local oscillator signal is required to be higher than the preset isolation threshold. At the same time, each local oscillator signal is required to have a common crystal oscillator reference to ensure the amplitude and phase consistency of the local oscillator signal after phase-locked loop frequency multiplication. Step S3.2: Mix each narrowband RF signal with local oscillator signals of different frequencies, downconvert each narrowband RF signal to the same intermediate frequency signal, and then filter out the image frequency through intermediate frequency filtering; Step S3.3: Perform bandpass sampling on the intermediate frequency narrowband radio frequency signal to obtain the narrowband digital signal after spectrum shifting; Step S3.4: Perform digital decimation on the narrowband digital signal after spectrum shifting in step S3.3 to reduce the data rate, and then filter the decimated narrowband digital signal to remove high-order harmonic components.

7. The method according to claim 6, characterized in that, Step S4 specifically includes the following steps: Step S4.1: Use digital downconversion to mix the narrowband digital signal of each channel obtained in step S3 with local oscillator signals of different frequencies, and shift the narrowband digital signal obtained in step S3 to the baseband for channelization processing. Step S4.2: The baseband sub-signals of each channel are processed by channel division filtering. On the one hand, the image signal after down-conversion is filtered out, and on the other hand, the baseband is uniformly digitally channelized to obtain the narrowband sub-signals of multiple channels.

8. The method according to any one of claims 5 to 7, characterized in that, Step S5 specifically includes the following steps: Step S5.1: Perform polyphase interpolation and low-pass filtering on the narrowband sub-signals of each channel to restore the broadband radio frequency signal data rate and filter out the harmonic components caused by interpolation; Step S5.2: Upconvert the interpolated and filtered baseband signal and the local oscillator signals of different frequencies, and then send them together into the synthesizer to splice them to obtain the reconstructed signal of the original working bandwidth; Step S6 specifically includes the following steps: Step S6.1: Couple the generated calibration signal and the received broadband radio frequency signal into the link; wherein, the frequency of the calibration signal is the center frequency of the overlapping area of ​​adjacent channel frequency bands; Step S6.2: Calculate the phase difference of the calibration signal between adjacent channels; Step S6.3: Substitute the phase difference into the calibration coefficient calculation formula to obtain the calibration coefficient, perform phase compensation on the channel, and obtain the reconstructed signal after phase calibration; Step S6.4: Upconvert the reconstructed signal after phase calibration to an RF signal, and transmit it to the frequency hopping communication system through digital-to-analog conversion.

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