Automatically adaptable multi-system frequency hopping step tracking receiving device and method

Abstract

The present invention belongs to the field of communication technology and relates to an automatically adaptive multi-system frequency hopping step tracking receiving device and method. The device and method comprise: a dynamic bandwidth adaptation module automatically switches bandwidth states through short-time energy detection; a frequency hopping synchronization tracking module performs frequency tracking on a captured frequency based on a bandwidth adaptation signal; an adaptive AGC loop comprises a digital detection receiver and an intermediate frequency receiving unit, and is used to perform mixed gain control on a phase synchronization signal; the intermediate frequency receiving unit is used to coarsely adjust the gain and output a digital signal; the digital detection receiver performs amplitude envelope detection on the digital signal, calculates a digital AGC voltage, feeds the digital AGC voltage back to the intermediate frequency receiving unit to form an analog-digital hybrid closed loop, and outputs a modulated signal. Simultaneously, the output AGC voltage cooperates with the target signal to complete amplitude self-tracking. The device solves the problems of automatically tracking multiple modulation signals involved and adaptive multi-system frequency hopping step tracking in an antenna tracking system.

Description

Technical Field

[0001] The invention relates to the field of communication technology, and in particular discloses an automatic adaptive multi-system frequency hopping step tracking receiving device and method. Background Art

[0002] Receivers need to adapt to dynamic signals in the digital domain, requiring an AGC design in the digital domain. The AGC controls the coherent frequency conversion output from the carrier phase-locked loop (PLL). Once the carrier phase-locked loop locks onto the signal, the coherent frequency conversion results reflect a portion of the signal power, thereby controlling the signal power and maintaining it at a fixed level. A high-precision AGC loop based on amplitude tracking technology uses a "quantity" within the loop to track the input signal amplitude. After amplitude tracking is achieved, the gain factor is calculated based on the ratio of the obtained amplitude to the desired threshold, thereby normalizing the signal. This approach completely resolves the linear system issues of the AGC loop and achieves high-precision normalized signal power control. After a standard TT&C and loop receiver completes frequency guidance and carrier acquisition tracking, the carrier loop output signal undergoes detection, which then cooperates with the AGC loop to track the AGC voltage output. However, existing approaches can only track and demodulate continuous signals. Tracking and demodulation of frequency-hopping modulated signals becomes impossible, and adapting to varying frequency-hopping modulation signals is even more difficult.

[0003] In view of this, the present invention proposes an automatic adaptive multi-system frequency hopping step tracking receiving device and method, which solves the problem of automatic tracking of multiple modulated signals involved and adaptive multi-system frequency hopping step tracking in an antenna tracking system. Summary of the Invention

[0004] The present invention aims to provide an automatically adaptive multi-system frequency hopping step tracking receiving device, which specifically comprises a dynamic bandwidth adaptation module, a frequency hopping synchronization tracking module and an adaptive AGC loop. The dynamic bandwidth adaptation module automatically switches bandwidth states through short-time energy detection, intercepts a central bandwidth where signal energy is concentrated, and outputs a bandwidth adaptation signal. The frequency hopping synchronization tracking module searches for frequency hopping signals according to a preset frequency list for the bandwidth adaptation signal, and performs frequency tracking on the captured frequencies to obtain a phase synchronization signal. The adaptive AGC loop comprises a digital detection receiver and an intermediate frequency receiving unit for performing mixed gain control on the phase synchronization signal. The intermediate frequency receiving unit is used for coarse gain adjustment and outputs a digital signal. The digital detection receiver performs amplitude envelope detection on the digital signal, calculates a digital AGC voltage, and feeds the digital AGC voltage back to the intermediate frequency receiving unit to form an analog-digital hybrid closed loop. The digital detection receiver also outputs a modulated signal and the output AGC voltage cooperates to achieve amplitude self-tracking of the target signal.

[0005] Furthermore, the digital detection receiver includes an automatic gain control unit, a first DSP and a first FPGA; the automatic gain control unit is used to receive an intermediate frequency signal, preliminarily adjust the amplitude through an analog attenuator, and output it to an A / D converter; the A / D converter, driven by a clock unit, digitizes the analog signal and outputs it to the first FPGA; the first FPGA implements an amplitude envelope detection algorithm, calculates signal power and generates AGC control instructions, outputs an analog AGC voltage through a D / A converter, and simultaneously transmits the demodulated signal to a serial port unit; the first DSP is used to optimize the detection parameters of the first FPGA and support switching of demodulation algorithms for multiple modulated signals.

[0006] Furthermore, the intermediate frequency receiving unit includes an AGC intermediate frequency amplifier, a second FPGA and a second DSP; the AGC intermediate frequency amplifier receives the intermediate frequency signal, dynamically adjusts the gain through the AGC voltage fed back by the D / A converter, and outputs it to the automatic gain control module; the second FPGA performs dynamic bandwidth filtering and power normalization calculation on the digital intermediate frequency signal, and outputs it to the second DSP and the D / A converter; the second DSP runs a frequency hopping step search algorithm to generate the preset frequency list, drives the frequency synthesizer through the crystal oscillator, and cooperates with the second FPGA to complete the capture and tracking of the frequency hopping signal.

[0007] Furthermore, the modulated signal includes a global beam mode frequency hopping signal and a spot beam mode frequency hopping signal.

[0008] The present invention also provides an automatic adaptive multi-system frequency hopping step tracking receiving method, comprising: according to the input signal system, automatically switching the bandwidth width through short-time energy detection of the sum signal, and intercepting the signal center bandwidth; if the short-time energy is greater than or equal to the threshold, it is determined to be a valid signal and is selected to the adaptive AGC loop; if the short-time energy is less than the threshold, the signal is discarded to avoid noise interference gain adjustment; through analog front-end coarse adjustment and digital back-end fine adjustment, the output signal amplitude is stabilized at the target level.

[0009] Furthermore, the time length of the short-time energy detection is 10 μs; and the frequency hopping rate of the frequency hopping signal is 20,000 hops / s.

[0010] Furthermore, the bandwidth includes wide bandwidth and narrow bandwidth; the wide bandwidth is 5 MHz, which is used to process strong signals or wideband frequency hopping signals; the narrow bandwidth is 1 MHz, which is used to process weak signals or narrowband frequency hopping signals.

[0011] Furthermore, the strong signal or wideband frequency hopping signal includes a spot beam frequency hopping signal; the weak signal or narrowband frequency hopping signal includes a global beam frequency hopping signal, and the bandwidth is automatically switched by detecting signal energy.

[0012] Furthermore, when the bandwidth is narrow, the sum signal is a Σ channel signal of a single pulse tracking system.

[0013] Furthermore, the input signal is an intermediate frequency signal with a center frequency of 70 MHz.

[0014] The present invention has the following advantages and beneficial effects:

[0015] The multi-system frequency-hopping stepped tracking device and method designed in this invention can accommodate frequency-hopping signals in both spot-beam and global-beam frequency-hopping modes, demodulating and outputting AGC tracking electrical signals that meet tracking requirements. Furthermore, tracking of both beacon signals and broadband modulated signals is integrated into a single module, achieving a higher level of integration while significantly reducing the size of existing single-pulse tracking systems.

[0016] The present invention overcomes the problem that the earlier "communication in motion" antenna system has no tracking of frequency hopping modulation signals, only tracking of continuous beacon signals and broadband signals, and if tracking of discontinuous frequency hopping signals is required, a separate set of frequency hopping tracking receiving equipment is required for tracking and demodulation. The present application only requires one set of equipment to complete tracking and demodulation of multiple systems, and at the same time the volume is reduced on the original basis, meeting the application in multiple scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is an exemplary schematic diagram of the digital detection receiver proposed in the present invention;

[0018] Figure 2 This is an exemplary schematic diagram of the intermediate frequency receiving unit proposed in the present invention. DETAILED DESCRIPTION

[0019] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0020] The invention proposes an automatic adaptive multi-system frequency hopping step tracking receiving device, which comprises a dynamic bandwidth adaptive module, a frequency hopping synchronous tracking module and an adaptive AGC loop.

[0021] The dynamic bandwidth adaptation module automatically switches bandwidth widths through short-term energy detection, intercepting the central bandwidth where signal energy is concentrated and outputting a bandwidth-adapted signal. Short-term energy detection involves calculating the energy (e.g., mean squared value) of the summed signal within a preset 10μs time window to determine whether the signal is a valid onboard signal and to switch bandwidths. Bandwidths include wide and narrow. The wide bandwidth is 5MHz and is used to process strong signals or wideband frequency-hopping signals; the narrow bandwidth is 1MHz and is used to process weak signals or narrowband frequency-hopping signals. Strong signals are signals in spot-beam frequency-hopping mode, where the target transmits within a defined range, resulting in concentrated energy and high signal strength. Wideband frequency-hopping signals are those with wide hopping intervals or a large signal bandwidth (e.g., spot-beam frequency-hopping signals). Weak signals are those in global-beam frequency-hopping mode, where the target transmits in all directions, resulting in scattered energy and low signal strength. Narrowband frequency-hopping signals are those with narrow hopping intervals or a small signal bandwidth (e.g., global-beam frequency-hopping signals). A bandwidth-adaptive signal is a signal that has been filtered through a dynamic bandwidth filter to reduce the center bandwidth, adapting to the strength and bandwidth characteristics of the current signal (e.g., a 70MHz IF signal with a 5MHz or 1MHz bandwidth). For example, when a spot beam frequency-hopping signal (strong signal, wide bandwidth) is received, the dynamic bandwidth adaptation module uses a 10μs short-term energy detection to determine if the energy exceeds the threshold and automatically switches to a 5MHz wide bandwidth, intercepting the signal output within ±2.5MHz of the 70MHz center frequency.

[0022] The frequency hopping synchronization tracking module searches for frequency hopping signals based on the bandwidth adaptation signal according to a preset frequency list and performs frequency tracking on the captured frequencies to obtain a phase-synchronized signal. The preset frequency list is a list of possible frequency points where the frequency hopping signal may appear (e.g., candidate frequencies within the range of 70 MHz ± 5 MHz) and is used for step-wise signal search. The preset frequency list can be generated by analyzing historical frequency hopping patterns, signal characteristics, or external input commands. Searching for frequency hopping signals according to the preset frequency list involves using a step-wise search algorithm, starting from the starting frequency in the preset frequency list (e.g., 70 MHz - 5 MHz), and detecting the signal energy at each frequency point one by one (e.g., using an FFT transform) with a fixed step size (e.g., 1 MHz). When the energy exceeds a threshold, the frequency is captured. Frequency tracking of the captured frequency involves locking the carrier phase using a carrier phase-locked loop (PLL) and using a Doppler shift prediction model (e.g., a Kalman filter) to adjust the local frequency in real time, ensuring a tracking accuracy of ≤100 Hz. The phase-synchronized signal is a digital intermediate frequency signal whose frequency and phase are aligned with the input frequency hopping signal and is used for subsequent coherent demodulation. For example, for global beam-hopping frequency signals (weak signals, narrow frequencies), the module outputs a bandwidth-adaptive signal with a narrow bandwidth of 1 MHz, searches in steps according to a preset frequency list, captures the 70 MHz center frequency signal through FFT, locks the phase using PLL, and outputs a phase-synchronized signal.

[0023] The adaptive AGC loop includes a digital detector receiver and an intermediate frequency (IF) receiving unit, which performs hybrid gain control on the phase-synchronized signal. The IF receiving unit performs coarse gain adjustment and outputs a digital signal. The digital detector receiver performs amplitude envelope detection on the digital signal, calculates the digital AGC voltage, and feeds this voltage back to the IF receiving unit, forming an analog-digital hybrid closed loop. The digital detector receiver also outputs the modulated signal and the AGC voltage, which coordinates with the amplitude self-tracking of the target signal. Hybrid gain control is a closed-loop control method that combines coarse gain adjustment in the analog front end (IF receiving unit) with fine gain adjustment in the digital back end (digital detector receiver). Coarse gain adjustment rapidly adjusts the signal amplitude via the AGC IF amplifier (analog front end), with a response time of ≤1μs and a wide dynamic range (≥60dB). Amplitude envelope detection extracts AGC voltage information from the input tracking frequency-hopping modulation signal (such as global beam mode frequency-hopping signals, spot beam mode frequency-hopping signals, and other frequency-hopping signals). The AGC voltage is the analog voltage signal used to control gain. The AGC voltage refers to an analog voltage signal used to control gain, generated from signal power detection results (e.g., the voltage output by a D / A converter). The digital AGC voltage refers to a digital gain control parameter generated through digital signal processing (e.g., DSP calculation of the mean squared value of signal power). An analog-digital hybrid closed loop system involves the AGC intermediate frequency amplifier (analog front-end) and digital detection receiver (back-end) working together through a feedback link to form an "analog coarse adjustment → digital fine adjustment" closed loop (e.g., the digital AGC voltage is fed back to the analog amplifier to adjust the gain). A modulated signal refers to a modulated signal containing target information, such as an OOK modulated signal or a frequency-hopping signal. In some embodiments, the modulated signal is a 2.176 MHz OOK modulated signal. An OOK modulated signal is a signal that transmits data by switching the carrier on and off (on-off keying), such as a 2.176 MHz baseband signal. A target signal refers to a valid signal transmitted by a satellite, such as a spot beam signal, a global beam frequency-hopping signal, or a beacon signal. Amplitude self-tracking refers to dynamically adjusting the gain through the AGC loop to stabilize the output signal amplitude at a preset target level (e.g., ±1dB error). For example, when a phase-synchronized signal enters the IF receiver, the AGC IF amplifier first coarsely adjusts the gain (e.g., amplifying the signal amplitude from -60dBm to -30dBm). After A / D conversion, the digital signal enters the digital detection receiver. The FPGA calculates the power through amplitude envelope detection and generates a digital AGC voltage (e.g., a control gain of +5dB), which is fed back to the front end, forming a hybrid closed loop and outputting a stable 2.176MHz OOK signal.

[0024] like Figure 1As shown, the digital detection receiver includes an automatic gain control unit (AGC), a first DSP, a first FPGA, and an OOK modulation module. The AGC receives a 70 MHz intermediate frequency (IF) signal, performs preliminary amplitude adjustment using an analog attenuator, and outputs the signal to an A / D converter. This initial amplitude adjustment involves using the analog attenuator to adjust the amplitude of the input 70 MHz IF signal (e.g., attenuate it by 20 dB) to prevent overload or signal loss in the A / D converter. Driven by a clock unit, the A / D converter digitizes the analog signal and outputs it to the first FPGA. The first FPGA implements an amplitude envelope detection algorithm, calculates signal power, and generates AGC control instructions. The AGC control instruction outputs an analog AGC voltage via the D / A converter and simultaneously transmits the demodulated signal to the serial port module. The AGC control instruction is a gain adjustment instruction generated by the FPGA based on the signal power calculation result, such as "Gain +3 dB" or "Gain -5 dB." The analog AGC voltage is an analog voltage signal (e.g., 1 V corresponds to a certain gain value) converted by the D / A converter to control the AGC IF amplifier. The first DSP is used to optimize the detection parameters of the first FPGA and support demodulation algorithm switching for multiple modulation signals. Detection parameters affect detection performance. These parameters may include threshold B, low-pass filter cutoff frequency, and energy detection window (10 μs). The OOK modulation module outputs an OOK modulated signal (e.g., a 2.176 MHz modulation signal) to control an LNB (low-noise amplifier).

[0025] like Figure 2As shown, the IF receiving unit includes an AGC IF amplifier, a second FPGA, and a second DSP. The AGC IF amplifier receives the IF signal, dynamically adjusts the gain using the AGC voltage fed back by the D / A converter, and outputs the signal to the automatic gain control module. The second FPGA performs dynamic bandwidth filtering and power normalization on the digital IF signal, outputting the signal to the second DSP and D / A converter. Dynamic bandwidth filtering involves switching the filter bandwidth (5MHz / 1MHz) based on the signal energy detection results. For example, a narrow 1MHz bandwidth filter is used for global beam hopping signals (weak signals) to suppress out-of-band noise. Power normalization calculates the signal's root mean square (RMS) power to adjust the signal amplitude to a uniform level. Specifically, the RMS power of the digital IF signal is calculated and compared with a target level to generate a gain adjustment parameter. For example, if the RMS power is lower than the target level, a "Gain +" instruction is generated. The second DSP runs a frequency hopping step search algorithm to generate the preset frequency list. It then drives the frequency synthesizer via a crystal oscillator, collaborating with the second FPGA to capture and track the frequency hopping signal. A frequency-hopping step search algorithm searches for a frequency-hopping signal one by one according to a preset frequency list. Specifically, it starts at the lowest frequency in the list and checks the signal energy at each frequency in a fixed step size (e.g., 1 MHz) until it finds a signal (e.g., a frequency with energy exceeding a threshold).

[0026] The present invention also provides an automatically adaptive multi-system frequency hopping step tracking reception method, comprising: automatically switching the bandwidth width based on the input signal system through short-term energy detection of the summing-path signal, and intercepting the signal center bandwidth. The input signal system refers to the modulation type and parameters of the signal, and can include frequency hopping (spot beam / global beam), beacon, and wideband modulation. In some embodiments, the input signal is an intermediate frequency signal with a center frequency of 70 MHz. The summing-path signal refers to the Σ channel signal in a single pulse tracking system, formed by coherent superposition of multi-antenna signals, and is used to enhance signal energy and suppress noise.

[0027] In some embodiments, the short-term energy detection duration is 10 μs; the frequency hopping rate of the frequency hopping signal is 20,000 hops / s. In some embodiments, when the bandwidth is narrow, the sum signal is a Σ channel signal of a monopulse tracking system. This enhances signal energy and suppresses noise through coherent superposition, thereby improving weak signal detection sensitivity. The Σ channel signal of a monopulse tracking system refers to the sum signal obtained by adding signals received by multiple antennas in a monopulse antenna system. For example, after Σ channel coherent superposition of a global beam hopping signal, signal energy is enhanced and noise is canceled, facilitating weak signal detection. The bandwidth refers to the signal frequency range allowed to pass by the filter. For example, 5 MHz (70 MHz ± 2.5 MHz) or 1 MHz (70 MHz ± 0.5 MHz). In some embodiments, the bandwidth includes a wide bandwidth and a narrow bandwidth. The wide bandwidth is 5 MHz, used to process strong signals or wideband frequency hopping signals; the narrow bandwidth is 1 MHz, used to process weak signals or narrowband frequency hopping signals. In some embodiments, a strong signal or a wideband frequency hopping signal includes a spot beam frequency hopping signal; a weak signal or a narrowband frequency hopping signal includes a global beam frequency hopping signal, and the bandwidth is automatically switched by detecting the signal energy. A spot beam frequency hopping signal refers to a strong signal, a wideband frequency hopping signal that is transmitted by a target to a specific area. For example, a frequency hopping signal within the coverage area of ​​a satellite spot beam. A global beam frequency hopping signal refers to a weak signal, a narrowband frequency hopping signal that is transmitted by a target in all directions. For example, a frequency hopping signal within the global coverage area of ​​a satellite. Automatically switching the bandwidth width refers to automatically selecting the bandwidth based on the short-term energy detection results. For example, when strong signal energy is detected, the bandwidth is switched to a wide bandwidth of 5 MHz, and when weak signal energy is detected, the bandwidth is switched to a narrow bandwidth of 1 MHz. Intercepting the center bandwidth of the signal refers to selecting the center bandwidth where the energy is concentrated within the frequency range where the signal is located. For example, for a 70 MHz intermediate frequency signal, a 5 MHz bandwidth intercepts 70 MHz ± 2.5 MHz, and a 1 MHz bandwidth intercepts 70 MHz ± 0.5 MHz.

[0028] If the short-term energy is greater than or equal to the threshold, the signal is determined to be valid and is passed to the adaptive AGC loop. The threshold is the critical energy value that determines whether a signal is valid. For example, the preset energy level B is used to distinguish valid onboard signals from noise. A valid signal is a valid onboard signal whose energy exceeds the threshold. For example, a frequency-hopping beacon or data signal transmitted by a satellite. If the short-term energy is less than the threshold, the signal is discarded to prevent noise from interfering with gain adjustment.

[0029] The output signal amplitude is stabilized at the target level through coarse adjustment at the analog front end and fine adjustment at the digital back end. Coarse adjustment at the analog front end involves rapid signal gain adjustment via the AGC IF amplifier. For example, the AGC IF amplifier adjusts the signal gain from 0dB to 30dB within 1μs to accommodate sudden changes from strong to weak signals. Fine adjustment at the digital back end involves precise gain adjustment via the DSP / FPGA in the digital detection receiver. For example, the DSP calculates the RMS power of the signal and generates a digital AGC voltage to maintain a gain error of ≤±0.1dB. The output signal is the stable signal after demodulation and gain control. For example, the output signal can be a 2.176MHz OOK modulated signal or a normalized digital IF signal. The target level is the desired signal amplitude level. For example, the target level can be the level corresponding to the full-scale range of the A / D converter (e.g., 1V±0.1dB) to ensure effective signal sampling.

[0030] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. An automatic adaptive multi-system frequency hopping step tracking receiver, characterized in that: It includes dynamic bandwidth adaptation module, frequency hopping synchronization tracking module and adaptive AGC loop; The dynamic bandwidth adaptation module automatically switches the bandwidth width through short-time energy detection, intercepts the central bandwidth where the signal energy is concentrated, and outputs a bandwidth adaptation signal; the bandwidth width includes wide bandwidth and narrow bandwidth; the wide bandwidth is 5MHz, which is used to process strong signals or wide-band frequency hopping signals; the narrow bandwidth is 1MHz, which is used to process weak signals or narrow-band frequency hopping signals; The frequency hopping synchronization tracking module searches for a frequency hopping signal according to a preset frequency list for the bandwidth adaptation signal, and performs frequency tracking on the captured frequency to obtain a phase synchronization signal; The adaptive AGC loop includes a digital detection receiver and an intermediate frequency receiving unit, which are used to perform mixed gain control on the phase synchronization signal; the intermediate frequency receiving unit is used to coarsely adjust the gain and output a digital signal; the digital detection receiver performs amplitude envelope detection on the digital signal, calculates the digital AGC voltage, and feeds the digital AGC voltage back to the intermediate frequency receiving unit to form an analog-digital hybrid closed loop, and outputs the modulated signal. At the same time, the output AGC voltage cooperates to complete the amplitude self-tracking of the target signal.

2. The automatic adaptive multi-system frequency hopping step tracking receiving device according to claim 1, characterized in that: The digital detection receiver includes an automatic gain control unit, a first DSP and a first FPGA; The automatic gain control unit is used to receive the intermediate frequency signal, preliminarily adjust the amplitude through the analog attenuator, and output it to the A / D converter; The A / D converter is driven by the clock unit to digitize the analog signal and output it to the first FPGA; The first FPGA implements an amplitude envelope detection algorithm, calculates signal power and generates AGC control instructions, outputs analog AGC voltage through a D / A converter, and transmits the demodulated signal to the serial port unit; The first DSP is used to optimize the detection parameters of the first FPGA and support demodulation algorithm switching of multiple modulation signals.

3. The automatic adaptive multi-system frequency hopping step tracking receiver according to claim 1, characterized in that: The intermediate frequency receiving unit includes an AGC intermediate frequency amplifier, a second FPGA and a second DSP; The AGC intermediate frequency amplifier receives the intermediate frequency signal, dynamically adjusts the gain through the AGC voltage fed back by the D / A converter, and outputs the result to the automatic gain control module; The second FPGA performs dynamic bandwidth filtering and power normalization calculation on the digital intermediate frequency signal, and outputs the result to the second DSP and D / A converter; The second DSP runs a frequency hopping step search algorithm to generate the preset frequency list, drives the frequency synthesizer through a crystal oscillator, and cooperates with the second FPGA to complete the capture and tracking of the frequency hopping signal.

4. The automatic adaptive multi-system frequency hopping step tracking receiver according to claim 1, characterized in that: The modulated signal includes a global beam mode frequency hopping signal and a spot beam mode frequency hopping signal.

5. A method for automatically adapting to multi-system frequency hopping step tracking reception, characterized in that: include: According to the input signal system, the bandwidth is automatically switched through short-term energy detection of the combined signal to intercept the signal center bandwidth; the bandwidth includes wide bandwidth and narrow bandwidth; the wide bandwidth is 5MHz, which is used to process strong signals or wide-band frequency hopping signals; the narrow bandwidth is 1MHz, which is used to process weak signals or narrow-band frequency hopping signals; If the short-time energy is greater than or equal to the threshold, it is determined to be a valid signal and is passed to the adaptive AGC loop; If the short-time energy is less than the threshold, the signal is discarded to avoid noise interference with gain adjustment; The output signal amplitude is stabilized at the target level through coarse adjustment at the analog front end and fine adjustment at the digital back end. The adaptive AGC loop includes a digital detection receiver and an intermediate frequency receiving unit, which are used to perform mixed gain control on the phase synchronization signal. The intermediate frequency receiving unit is used to coarsely adjust the gain and output a digital signal. The digital detection receiver performs amplitude envelope detection on the digital signal, calculates the digital AGC voltage, and feeds the digital AGC voltage back to the intermediate frequency receiving unit to form an analog-digital hybrid closed loop, and outputs the modulated signal. At the same time, the output AGC voltage cooperates to complete the amplitude self-tracking of the target signal. Coarse adjustment at the analog front end refers to the rapid adjustment of the signal gain through the AGC intermediate frequency amplifier to adapt to the sudden change from strong signal to weak signal. Fine adjustment at the digital back end refers to the precise adjustment of the gain through the DSP / FPGA of the digital detection receiver.

6. The automatic adaptive multi-system frequency hopping step tracking receiving method according to claim 5, characterized in that: The time length of the short-time energy detection is 10 μs; the frequency hopping rate of the frequency hopping signal is 20,000 hops / s.

7. The automatic adaptive multi-system frequency hopping step tracking receiving method according to claim 5, characterized in that: Strong signals or wide-band frequency hopping signals include spot beam frequency hopping signals; weak signals or narrow-band frequency hopping signals include global beam frequency hopping signals, which automatically switch bandwidth by detecting signal energy.

8. The automatic adaptive multi-system frequency hopping step tracking receiving method according to claim 5, characterized in that: When the bandwidth is narrow, the sum signal is a Σ channel signal of a single pulse tracking system.

9. The automatic adaptive multi-system frequency hopping step tracking receiving method according to claim 5, characterized in that: The input signal is an intermediate frequency signal with a center frequency of 70 MHz.

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