CN111585609A - Miniaturized zero intermediate frequency fast frequency hopping radio station - Google Patents

Abstract

The embodiment of the invention provides a miniaturized zero intermediate frequency fast frequency hopping radio station, which comprises: a fast frequency hopping sending end generates an initial zero intermediate frequency mixed spread spectrum digital signal; the digital-to-analog converter converts an initial zero intermediate frequency mixed spread spectrum analog signal; the first low-pass filter filters out high-frequency components in the initial zero intermediate frequency mixed spread spectrum analog signal; the first mixer acquires an initial radio frequency mixed spread spectrum analog signal and transmits the signal through a first antenna, the second antenna receives the initial radio frequency mixed spread spectrum analog signal, and the second mixer acquires an integrated zero intermediate frequency mixed spread spectrum analog signal; the second low-pass filter acquires the integrated zero intermediate frequency mixed spread spectrum analog signal after filtering; the analog-to-digital converter converts the filtered integrated zero intermediate frequency mixed spread spectrum analog signal into an integrated zero intermediate frequency mixed spread spectrum digital signal; and the fast frequency hopping receiving end acquires the integrated zero intermediate frequency mixed spread spectrum digital signal. The invention adopts a mode of combining direct sequence spread spectrum and frequency hopping, has strong anti-interference capability, and occupies small resource amount by means of a zero intermediate frequency structure.

Description

A miniaturized zero-IF fast frequency hopping radio

technical field

The invention relates to the technical field of communication, in particular to a miniaturized zero-intermediate frequency fast frequency hopping radio station.

Background technique

Military wireless communication is the main means of communication to ensure modern combat command, and it is also the only means of communication to contact moving targets such as aircraft, missiles, and satellites. Anti-jamming measures must be provided. The fast frequency hopping communication with anti-multipath and anti-tracking interference ability has been widely used, which can realize data transmission under low signal-to-noise ratio.

Improving the spread spectrum gain and hopping speed can enhance the anti-interference ability of the frequency hopping system. For example, the CHESS high-speed frequency hopping radio station in the United States adopts the direct spread and frequency hopping hybrid spread spectrum method, and switches 5000 frequencies per second, which can provide reliable long-distance data transmission.

For narrowband interference located at some frequency points, it is difficult to directly counteract the spread spectrum gain when the interference signal ratio is too large, and appropriate anti-narrowband interference capability is required.

In addition, in order to meet the requirements of flexible and rapid deployment and concealment in the battlefield environment, the fast frequency hopping radio should also have the characteristics of low power consumption and miniaturization. Therefore, a miniaturized zero-IF fast frequency hopping radio is urgently needed.

SUMMARY OF THE INVENTION

In order to solve the above problem, an embodiment of the present invention provides a miniaturized zero-IF fast frequency hopping radio.

An embodiment of the present invention provides a miniaturized zero-IF fast frequency hopping radio, including: a fast frequency hopping transmitter, a digital-to-analog converter, a first low-pass filter, a first mixer, a first antenna, a second antenna, The second mixer, the second low-pass filter, the analog-to-digital converter and the fast frequency hopping receiver, wherein:

The fast frequency hopping transmitter is used to generate an initial zero-IF hybrid spread spectrum digital signal combined with direct sequence spread spectrum and frequency hopping spread spectrum;

The digital-to-analog converter is used to convert the initial zero-IF hybrid spread spectrum digital signal into an initial zero-IF hybrid spread spectrum analog signal;

The first low-pass filter is used to filter out high-frequency components in the initial zero-IF hybrid spread spectrum analog signal, and obtain the filtered initial zero-IF hybrid spread spectrum analog signal;

The first mixer is used for up-converting the filtered initial zero-IF hybrid spread spectrum analog signal from zero-IF to radio frequency to obtain the initial radio frequency hybrid spread spectrum analog signal;

the first antenna is used for transmitting the initial radio frequency hybrid spread spectrum analog signal;

the second antenna is used for receiving the initial radio frequency hybrid spread spectrum analog signal;

The second mixer is used for down-converting the initial radio frequency hybrid spread spectrum analog signal from radio frequency to zero-IF, and obtaining an integrated zero-IF hybrid spread spectrum analog signal;

The second low-pass filter is used to perform low-pass filtering on the integrated zero-IF hybrid spread-spectrum analog signal, and obtain the filtered and integrated zero-IF hybrid spread-spectrum analog signal;

The analog-to-digital converter is used to convert the filtered and integrated zero-IF hybrid spread spectrum analog signal into an integrated zero-IF hybrid spread spectrum digital signal;

The fast frequency hopping receiving end is used for acquiring an integrated zero-IF hybrid spread spectrum digital signal, and coherently receiving the integrated zero-IF hybrid spread spectrum digital signal to acquire binary data information.

Preferably, the fast frequency hopping sending end includes: a frequency offset processing module, a spread spectrum baseband generation module, a frequency hopping carrier generation module and a hybrid spread spectrum module, and the first end of the frequency offset processing module is connected to the spread spectrum baseband The first end of the generation module is connected, the second end of the frequency offset processing module is connected with the second end of the frequency hopping carrier generation simulation, and the second end of the spread spectrum baseband generation module is connected with the hybrid spread spectrum module The first end of the frequency hopping carrier generation module is connected with the second end of the hybrid spread spectrum simulation;

The frequency offset processing module is configured to provide the spread spectrum baseband generation module and the frequency hopping carrier generation module with a symbol period expansion and contraction amount corresponding to the Doppler frequency offset, and provide the frequency hopping carrier generation module Provide a frequency hopping pattern with frequency offset to generate fast frequency hopping digital signal with its own Doppler information;

The spread spectrum baseband generation module is configured to receive the period expansion and contraction amount transmitted by the frequency offset processing module, generate a baseband spread spectrum signal according to the transmission data and the spread spectrum code, and send it to the hybrid spread spectrum module;

The frequency hopping carrier generation module is configured to generate a frequency hopping carrier according to the frequency hopping pattern with frequency offset and the frequency hopping period with period expansion and contraction transmitted by the frequency offset processing module, and send it to the hybrid spread spectrum module;

The hybrid spread spectrum module is used for generating an initial zero-IF hybrid spread spectrum digital signal with Doppler frequency offset information according to the baseband spread spectrum signal of the spread spectrum baseband generation module and the frequency hopping carrier of the frequency hopping carrier generation module.

Preferably, the fast frequency hopping receiver specifically includes a coarse acquisition module, a Doppler local oscillator module, a fine search synchronization module and a demodulation module, wherein:

The coarse acquisition module is used to detect and delete interference frequency points, and then perform differential coherent acquisition on the received digital signal, and send frequency offset information with an accuracy of 4 times the symbol rate and code phase information with an accuracy of Tc/2 to the Doppler local oscillator module;

The Doppler local oscillator module is used to generate the zero-IF frequency hopping carrier for de-hopping according to the frequency offset information and code phase information provided by the coarse acquisition module, and when receiving a signal from the fine search synchronization module After the frequency offset information and code phase information of , update the zero-IF frequency hopping carrier;

The precise search synchronization module is used to provide frequency offset information with an accuracy of 5 Hz for the Doppler local oscillator module according to the de-hopped zero-IF frequency hopping carrier, and adjust the solution of the Doppler local oscillator according to the code phase information. Jump the window, and detect the position of the frame header data, and pass it to the demodulation module;

The demodulation module is configured to analyze the zero-IF signal of the data segment after de-hopping after the fine search synchronization module detects the frame header, and obtain binary data information.

Preferably, the fast frequency hopping sending end and the fast frequency hopping receiving end are implemented in a xc7k325tffg900-2L FPGA, and both use the same sampling rate and system clock of 122.88MHz, and the quantization bit width is both 16bit.

Preferably, both the digital-to-analog converter and the analog-to-digital converter are AD9371.

Preferably, the miniaturized zero-IF fast frequency hopping radio provided by the present invention further includes: a first high-speed interface and a second high-speed interface for high-speed data transmission between the FPGA and the AD9371. The fast frequency hopping sending end is connected to the digital-to-analog converter through the first high-speed interface, and the first high-speed interface is used to transmit the initial zero-IF hybrid spread spectrum digital signal, and the analog-to-digital conversion The device is connected to the fast frequency hopping receiving end through the second high-speed interface, and the second high-speed interface is used to transmit the integrated zero-IF hybrid spread spectrum digital signal.

Preferably, the center frequency of the initial zero-IF hybrid spread spectrum digital signal is 0 Hz, and 64 frequency hopping frequency points evenly distributed in the range of ±40.96 MHz are used, with two frequency hopping patterns of 8 hops and 64 hops.

Preferably, the initial zero-IF hybrid spread spectrum signal uses a spread spectrum ratio with a length of 1024 points, BPSK modulation and square wave shaping, the transmitted data includes a frame header and a data segment, the oversampling multiple is 96, and the frequency hopping pattern is 64 hops. , the spread spectrum gain is 46dB.

Preferably, the center frequency of the initial radio frequency hybrid spread spectrum analog signal is 15.72864 GHz.

Preferably, the first high-speed interface and the second high-speed interface use a high-speed serial interface JESD204B.

A miniaturized zero-IF fast frequency hopping radio provided by the embodiment of the present invention adopts the combination of direct expansion and frequency hopping, and has strong anti-interference ability. All are implemented in a V7 series FPGA, occupying a small amount of resources, and can be compatible with a variety of platforms and systems; the transmitter can freely set the frequency offset, and can self-simulate the Doppler effect even in a wired test environment; with the help of AD9371 to complete the signal High-speed transmission and transceiver, with the characteristics of miniaturization and low power consumption; in addition, with frequency domain anti-jamming algorithm, it can work against 60dB narrowband interference.

Description of drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description These are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained according to these drawings without creative efforts.

1 is a schematic structural diagram of a miniaturized zero-IF fast frequency hopping radio according to an embodiment of the present invention;

FIG. 2 is a schematic structural diagram of a zero-IF fast frequency hopping transmitter according to an embodiment of the present invention;

FIG. 3 is a schematic structural diagram of a zero intermediate frequency fast frequency hopping receiver according to an embodiment of the present invention.

Detailed ways

In order to make the purposes, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments These are some embodiments of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

FIG. 1 is a schematic structural diagram of a miniaturized zero-IF fast frequency hopping radio according to an embodiment of the present invention. As shown in FIG. 1 , the structure of the fast frequency hopping radio includes: a fast frequency hopping transmitter 101 and a digital-to-analog converter 102 , a first low-pass filter 103, a first mixer 104, a first antenna 105, a second antenna 106, a second mixer 107, a second low-pass filter 108, an analog-to-digital converter 109 and a fast frequency hopping The receiving end 110, wherein:

The fast frequency hopping transmitter 101 is used to generate an initial zero-IF hybrid spread spectrum digital signal combined with direct sequence spread spectrum and frequency hopping spread spectrum;

The digital-to-analog converter 102 is configured to convert the initial zero-IF hybrid spread spectrum digital signal into an initial zero-IF hybrid spread spectrum analog signal;

The first low-pass filter 103 is used to filter out high-frequency components in the initial zero-IF hybrid spread spectrum analog signal, and obtain the filtered initial zero-IF hybrid spread spectrum analog signal;

The first mixer 104 is configured to transform the filtered initial zero-IF hybrid spread-spectrum analog signal from zero-IF to radio frequency to obtain an initial radio-frequency hybrid spread-spectrum analog signal;

The first antenna 105 is used for transmitting the initial radio frequency hybrid spread spectrum analog signal;

The second antenna 106 is configured to receive the initial radio frequency hybrid spread spectrum analog signal;

The second mixer 107 is configured to transform the initial radio frequency hybrid spread spectrum analog signal from radio frequency to zero intermediate frequency, and obtain an integrated zero intermediate frequency hybrid spread spectrum analog signal;

The second low-pass filter 108 is used for filtering the integrated zero-IF hybrid spread-spectrum analog signal to obtain the filtered and integrated zero-IF hybrid spread-spectrum analog signal;

The analog-to-digital converter 109 is used to convert the filtered and integrated zero-IF hybrid spread spectrum analog signal into an integrated zero-IF hybrid spread spectrum digital signal;

The fast frequency hopping receiving end 110 is used for acquiring an integrated zero-IF hybrid spread spectrum digital signal, and coherently receiving the integrated zero-IF hybrid spread spectrum digital signal to acquire binary data information.

In this embodiment of the present invention, the fast frequency hopping transmitting end and the fast frequency hopping receiving end are collectively referred to as a digital logic part, a digital-to-analog converter, a first low-pass filter, a first mixer, a first antenna, a second antenna, a first The second mixer, the second low-pass filter and the analog-to-digital converter are collectively referred to as the analog hardware part. The digital logic part is connected to the analog hardware part to provide the latter with digital signals and receive the returned signal. The digital logic part is in a xc7k325tffg900 -2L type FPGA is implemented in the same sampling rate and system clock of 122.88MHz, and the quantization bit width is 16bit.

The fast frequency hopping transmitter is used to generate a zero-IF hybrid spread spectrum signal combined with direct sequence spread spectrum and frequency hopping spread spectrum, and transmit it to the hardware simulation part.

The fast frequency hopping receiving end performs coherent reception and data analysis on the signal according to the received signal returned by the hardware analog part.

The analog hardware part is connected with the digital logic part. On the one hand, the analog hardware part transmits the zero-IF digital signal generated by the digital logic part at high speed and converts it into an analog RF signal for transmission; on the other hand, it converts the received RF signal into a zero-IF digital signal and transmits it. high-speed transfer to the digital logic section.

In the analog hardware part, the zero-IF digital signal is first converted into an analog radio frequency signal for transmission. The circuit of the transmitting part is composed of a digital-to-analog converter, a first low-pass filter, a first mixer and a first antenna. The digital-to-analog converter is composed of It can be directly connected with the fast frequency hopping sending end, or can be connected through a high-speed interface. In the embodiment of the present invention, the first high-speed interface 111 is used to connect the fast frequency hopping sending end and the digital-to-analog converter.

The first high-speed interface is responsible for fast transmission of digital signals between the digital logic part and the digital-to-analog converter.

The digital-to-analog converter is used for the conversion between the zero-IF fast frequency hopping digital signal and the analog signal, and converts the initial zero-IF mixed spread spectrum digital signal into the initial zero-IF mixed spread spectrum analog signal.

The first low-pass filter is used to filter out high frequency components in the initial zero-IF mixed spread spectrum analog signal.

The first mixer is used for up-converting the filtered initial zero-IF mixed spread spectrum analog signal to a radio frequency to obtain an initial radio frequency mixed spread spectrum analog signal.

The first antenna is used for transmitting the initial radio frequency hybrid spread spectrum analog signal.

The second antenna is used for receiving the initial radio frequency hybrid spread spectrum analog signal.

The second mixer is used for down-converting the radio frequency signal to zero intermediate frequency, specifically converting the initial radio frequency hybrid spread spectrum analog signal from radio frequency to zero intermediate frequency, and obtaining the integrated zero intermediate frequency hybrid spread spectrum analog signal.

The second low-pass filter is used to filter the integrated zero-IF mixed spread spectrum analog signal, and obtain the filtered and integrated zero-IF mixed spread spectrum analog signal.

The analog-to-digital converter is used to convert the filtered integrated zero-IF hybrid spread spectrum analog signal into an integrated zero-IF hybrid spread spectrum digital signal.

The analog-to-digital converter and the fast frequency hopping receiving end can be directly connected by wires, or can be connected through a high-speed interface. In the embodiment of the present invention, the second high-speed interface 112 is used to connect the analog-to-digital converter and the fast frequency hopping receiving end.

The fast frequency hopping receiving end is used to obtain the integrated zero-IF hybrid spread spectrum digital signal, and perform coherent reception on the integrated zero-IF hybrid spread spectrum digital signal to obtain binary data information.

A miniaturized zero-IF fast frequency hopping radio provided by the embodiment of the present invention adopts the combination of direct expansion and frequency hopping, and has strong anti-interference ability. All are implemented in a V7 series FPGA, occupying a small amount of resources, and can be compatible with a variety of platforms and systems; the transmitter can freely set the frequency offset, and can self-simulate the Doppler effect even in a wired test environment; with the help of AD9371 to complete the signal High-speed transmission and transceiver, with the characteristics of miniaturization and low power consumption; in addition, with frequency domain anti-jamming algorithm, it can work against 60dB narrowband interference.

On the basis of the above embodiment, preferably, the fast frequency hopping sending end includes: a frequency offset processing module, a spread spectrum baseband generation module, a frequency hopping carrier generation module and a hybrid spread spectrum module, and the first frequency offset processing module One end is connected to the first end of the spread spectrum baseband generation module, the second end of the frequency offset processing module is connected to the second end of the frequency hopping carrier generation simulation, and the second end of the spread spectrum baseband generation module is connected. The end is connected with the first end of the hybrid spread spectrum module, and the second end of the frequency hopping carrier generation module is connected with the second end of the hybrid spread spectrum simulation;

The frequency offset processing module is configured to provide the spread spectrum baseband generation module and the frequency hopping carrier generation module with a symbol period expansion and contraction amount corresponding to the Doppler frequency offset, and provide the frequency hopping carrier generation module Provide a frequency hopping pattern with frequency offset to generate fast frequency hopping digital signal with its own Doppler information;

The spread spectrum baseband generation module is configured to receive the period expansion and contraction amount transmitted by the frequency offset processing module, generate a baseband spread spectrum signal according to the transmission data and the spread spectrum code, and send it to the hybrid spread spectrum module;

The frequency hopping carrier generation module is configured to generate a frequency hopping carrier according to the frequency hopping pattern with frequency offset and the frequency hopping period with period expansion and contraction transmitted by the frequency offset processing module, and send it to the hybrid spread spectrum module;

The hybrid spread spectrum module is used for generating an initial zero-IF hybrid spread spectrum digital signal with Doppler frequency offset information according to the baseband spread spectrum signal of the spread spectrum baseband generation module and the frequency hopping carrier of the frequency hopping carrier generation module.

On the basis of the above embodiment, preferably, it further includes: a first high-speed interface and a second high-speed interface, wherein the fast frequency hopping sending end is connected to the digital-to-analog converter through the first high-speed interface, so The first high-speed interface is used to transmit the initial zero-IF hybrid spread spectrum digital signal, and the analog-to-digital converter is connected to the fast-frequency hopping receiving end through the second high-speed interface, and the second high-speed interface is used for The integrated zero-IF hybrid spread spectrum digital signal is transmitted.

Both the first high-speed interface and the second high-speed interface are used for high-speed data transmission between the FPGA and the AD9371.

Preferably, the high-speed interface uses the high-speed serial interface JESD204B, which can achieve a maximum transmission rate of 12.5 Gbps, and does not need to be aligned with the clock and the link.

Preferably, the center frequency of the radio frequency signal is 15.72864GHz.

As an option, the analog hardware part uses AD9371 chip to complete the transfer and conversion between digital zero-IF signal and analog RF signal, covering the functions of high-speed interface, ADC/DAC, low-pass filtering, and mixer.

FIG. 2 is a schematic structural diagram of a zero-IF fast frequency hopping transmitter according to an embodiment of the present invention. As shown in FIG. 2 , the fast frequency hopping transmitter includes a frequency offset processing module, a spread spectrum baseband generation module, and a frequency hopping carrier generation module. Module and hybrid spread spectrum module, in the figure "frequency offset processing" means frequency offset processing module, "spread spectrum baseband generation" means spread spectrum baseband generation module, "frequency hopping carrier generation" means frequency hopping carrier generation module, " "Hybrid Spread Spectrum" means the Hybrid Spread Spectrum module.

The frequency offset processing module provides the spread spectrum baseband generation module and the frequency hopping carrier generation module with a symbol period expansion corresponding to the Doppler frequency offset, and provides the frequency hopping carrier generation module with a frequency hopping pattern with frequency offset, To generate a fast frequency hopping digital signal with its own Doppler information.

The spread spectrum baseband generation module receives the period expansion and contraction amount transmitted by the frequency offset processing module, generates a baseband spread spectrum signal according to the transmitted data and the spread spectrum code, and transmits it to the hybrid spread spectrum module.

The frequency hopping carrier generation module generates a frequency hopping carrier according to the frequency hopping pattern with frequency offset and the frequency hopping period with period expansion and transmission transmitted by the frequency offset processing module, and transmits it to the hybrid spread spectrum module.

The hybrid spread spectrum module generates a hybrid spread spectrum signal with Doppler frequency offset information according to the baseband spread spectrum signal of the spread spectrum baseband generation module and the frequency hopping carrier of the frequency hopping carrier generation module, and transmits it to the high-speed interface of the analog hardware part.

Preferably, the center frequency point of the zero-IF hybrid spread spectrum signal is 0 Hz, and 64 frequency hopping frequency points uniformly distributed in the range of ±40.96 MHz are used, with two frequency hopping patterns of 8 hops and 64 hops.

Preferably, the zero-IF hybrid spread spectrum signal uses a spread spectrum ratio of 1024 points in length, BPSK modulation and square wave shaping, the transmitted data includes frame headers and data segments, and the oversampling multiple is 96. In the 64-hop working mode, the spread spectrum is The gain is 46dB.

Preferably, the zero-IF hybrid spread spectrum signal can simulate the frequency shift and period expansion caused by the Doppler effect.

Specifically, the symbol rate is 1250Ksps, in the 8-hop mode, all data 1 is used as a pilot segment for rough capture, and the duration is 132 symbols; in the 64-hop mode, a frame synchronization header with a length of 64 symbols is sent first, and then Send random data of unlimited length.

Specifically, the selected frequency hopping patterns have no overlapping frequencies, and each symbol is repeated once, with a hopping speed of 80,000 hops per second in the 64-hop mode and 10,000 hops per second in the 8-hop mode.

Specifically, the total bandwidth of frequency hopping is 81.92MHz, and the bandwidth at each frequency point is 2.56MHz.

FIG. 3 is a schematic structural diagram of a fast frequency hopping receiving end with zero intermediate frequency according to an embodiment of the present invention. As shown in FIG. 3 , the Doppler local oscillator in the figure represents a Doppler local oscillator module, and the fast frequency hopping receiving end Including coarse acquisition module, Doppler local oscillator, fine search synchronization module and demodulation module.

The coarse acquisition module is equipped with a frequency domain anti-jamming algorithm. First, the interference frequency points are detected and deleted, and then differential coherent acquisition is performed on the received digital signal, and the frequency offset information with an accuracy of 4 times the symbol rate and the code phase with an accuracy of Tc/2 are obtained. The information is passed to the Doppler LO.

The Doppler local oscillator first generates a zero-IF frequency hopping carrier for de-hopping according to the frequency offset information and code phase information provided by the coarse acquisition module; after receiving the frequency offset information and code phase information from the fine search synchronization module, Generates more precise frequency hopping carriers.

The precise search synchronization module provides frequency offset information with an accuracy of 5 Hz for the Doppler local oscillator according to the zero-IF signal after de-hopping, and adjusts the de-hopping window of the Doppler local oscillator according to the code phase information. At the same time, the position of the frame header data can also be detected and passed to the demodulation module.

After the precise search synchronization module detects the frame header, the demodulation module analyzes the zero-IF signal of the data segment after de-jumping to obtain binary data information.

Specifically, the detection interference frequency point of the synchronization module is finely searched, and the double threshold method is used to set the high and low thresholds according to the minimum power of the effective signal and the threshold coefficient, and the interference components are detected from the frequency hopping signal and deleted, and the useful components are retained.

Specifically, in the self-transmitting and self-receiving mode, the receiving delay τ is within (1/96) Tc (the oversampling rate is 96);

Specifically, the anti-Doppler range of the fast frequency hopping receiver is ±40kHz. It has been verified that the acquisition probability is 0.99573 (99573/100000) when Es/no is 7dB, and the acquisition probability is 0.98106 (98106) when Es/no is 6dB. /100000).

Specifically, when the JSR is 60dB and the Es/no is 7dB, the fast frequency hopping receiver can verify that the acquisition probability is 0.97653 (97653/100000), and the signal-to-noise ratio fallback is within 2dB.

To sum up, the present invention provides a design of a fast frequency hopping radio station with low power consumption and zero intermediate frequency structure, which adopts the combination of direct expansion and frequency hopping, the spread spectrum gain is 46dB, the hopping speed reaches 80,000 hops per second, and the anti-interference ability is strong. ;The transmitter can set the frequency offset freely, and can simulate the Doppler effect even in the wired test environment; With the help of the zero-IF structure, the digital logic of the transmitter and receiver of the fast frequency hopping radio is implemented in a V7 series FPGA, occupying The amount of resources is small, and it can be compatible with various platforms and systems; with the help of AD9371 to complete high-speed signal transmission and reception, it has the characteristics of miniaturization and low power consumption; Under the narrowband interference of 60dB, the signal-to-noise ratio falls back within 2dB.

The device embodiments described above are only illustrative, wherein the units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in One place, or it can be distributed over multiple network elements. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution in this embodiment. Those of ordinary skill in the art can understand and implement it without creative effort.

From the description of the above embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus a necessary general hardware platform, and certainly can also be implemented by hardware. Based on this understanding, the above-mentioned technical solutions can be embodied in the form of software products in essence or the parts that make contributions to the prior art, and the computer software products can be stored in computer-readable storage media, such as ROM/RAM, magnetic A disc, an optical disc, etc., includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to perform the methods described in various embodiments or some parts of the embodiments.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, but not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that it can still be The technical solutions described in the foregoing embodiments are modified, or some technical features thereof are equivalently replaced; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims (10)

1. The utility model provides a miniaturized zero intermediate frequency fast frequency hopping radio station, its characterized in that, includes fast frequency hopping sending terminal, digital-to-analog converter, first low pass filter, first mixer, first antenna, second mixer, second low pass filter, analog to digital converter and fast frequency hopping receiving terminal, wherein:

the fast frequency hopping sending end is used for generating an initial zero intermediate frequency mixed spread spectrum digital signal combining direct sequence spread spectrum and frequency hopping spread spectrum;

the digital-to-analog converter is used for converting the initial zero intermediate frequency mixed spread spectrum digital signal into an initial zero intermediate frequency mixed spread spectrum analog signal;

the first low-pass filter is used for filtering out high-frequency components in the initial zero intermediate frequency mixed spread spectrum analog signal and acquiring a filtered initial zero intermediate frequency mixed spread spectrum analog signal;

the first mixer is used for up-converting the filtered initial zero intermediate frequency mixed spread spectrum analog signal from zero intermediate frequency to radio frequency to obtain an initial radio frequency mixed spread spectrum analog signal;

the first antenna is used for transmitting the initial radio frequency mixed spread spectrum analog signal;

the second antenna is used for receiving the initial radio frequency mixed spread spectrum analog signal;

the second mixer is used for down-converting the initial radio frequency mixed spread spectrum analog signal from radio frequency to zero intermediate frequency to obtain an integrated zero intermediate frequency mixed spread spectrum analog signal;

the second low-pass filter is used for performing low-pass filtering on the integrated zero intermediate frequency mixed spread spectrum analog signal to obtain an integrated zero intermediate frequency mixed spread spectrum analog signal after filtering;

the analog-to-digital converter is used for converting the filtered integrated zero intermediate frequency mixed spread spectrum analog signal into an integrated zero intermediate frequency mixed spread spectrum digital signal;

the fast frequency hopping receiving end is used for acquiring the integrated zero intermediate frequency mixed spread spectrum digital signal, and performing coherent reception on the integrated zero intermediate frequency mixed spread spectrum digital signal to acquire binary data information.

2. The miniaturized zero-if fast frequency hopping station of claim 1, wherein the fast frequency hopping transmitter comprises: the frequency offset processing module, the spread spectrum baseband generating module, the frequency hopping carrier generating module and the hybrid spread spectrum module, wherein a first end of the frequency offset processing module is connected with a first end of the spread spectrum baseband generating module, a second end of the frequency offset processing module is connected with a second end of the frequency hopping carrier generation simulation, the second end of the spread spectrum baseband generating module is connected with the first end of the hybrid spread spectrum module, and the second end of the frequency hopping carrier generating module is connected with the second end of the hybrid spread spectrum simulation;

the frequency offset processing module is used for providing symbol period expansion and contraction quantity corresponding to Doppler frequency offset for the spread spectrum baseband generation module and the frequency hopping carrier generation module, and providing frequency hopping patterns with frequency offset for the frequency hopping carrier generation module so as to generate fast frequency hopping digital signals with Doppler information;

the spread spectrum baseband generation module is used for receiving the period expansion and contraction quantity transmitted by the frequency deviation processing module, generating a baseband spread spectrum signal according to the transmission data and the spread spectrum code and transmitting the baseband spread spectrum signal to the mixed spread spectrum module;

the frequency hopping carrier generation module is used for generating a frequency hopping carrier according to the frequency hopping pattern with the frequency offset and the frequency hopping cycle with the cycle expansion and contraction transmitted by the frequency offset processing module and transmitting the frequency hopping carrier to the hybrid spread spectrum module;

the mixed spread spectrum module is used for generating an initial zero intermediate frequency mixed spread spectrum digital signal with Doppler frequency offset information according to the baseband spread spectrum signal of the spread spectrum baseband generation module and the frequency hopping carrier of the frequency hopping carrier generation module.

3. The miniaturized zero-if fast frequency hopping radio station according to claim 1, wherein the fast frequency hopping receiving end specifically includes a coarse capture module, a doppler local oscillator module, a fine search synchronization module, and a demodulation module, wherein:

the coarse acquisition module is used for detecting interference frequency points to delete, then carrying out differential coherent acquisition on the received digital signals, and sending frequency offset information with the precision of 4 times of symbol rate and code phase information with the precision of Tc/2 to the Doppler local oscillator module;

the Doppler local oscillator module is used for generating the zero intermediate frequency hopping carrier wave for debounce according to the frequency offset information and the code phase information provided by the coarse capture module, and updating the zero intermediate frequency hopping carrier wave after receiving the frequency offset information and the code phase information from the fine search synchronization module;

the fine search synchronization module is used for providing frequency offset information with the precision of 5Hz for the Doppler local oscillator module according to the zero intermediate frequency hopping carrier wave after being subjected to debounce, adjusting a debounce window of the Doppler local oscillator according to code phase information, detecting the position of frame header data, and transmitting the position to the demodulation module;

and the demodulation module is used for analyzing the data segment zero intermediate frequency signal after the fine search synchronization module detects the frame header to obtain binary data information.

4. The miniaturized zero-if fast frequency hopping radio station according to claim 1, wherein the fast frequency hopping transmitting terminal and the fast frequency hopping receiving terminal are implemented in an xc7k325tffg900-2L model FPGA, which both uses the same sampling rate and system clock 122.88MHz, and the quantization bit width is 16 bits.

5. The miniaturized zero-if fast frequency hopping radio station of claim 1, further comprising: the fast frequency hopping transmitter is connected with the digital-to-analog converter through the first high-speed interface, the first high-speed interface is used for transmitting the initial zero intermediate frequency mixed spread spectrum digital signal, the analog-to-digital converter is connected with the fast frequency hopping receiver through the second high-speed interface, and the second high-speed interface is used for transmitting the integrated zero intermediate frequency mixed spread spectrum digital signal.

6. The miniaturized zero if fast frequency hopping radio of claim 5, wherein the digital-to-analog converter and the analog-to-digital converter are both AD 9371.

7. The miniaturized zero-if fast frequency hopping station according to claim 1, wherein the center frequency point of the initial zero-if mixed spread spectrum digital signal is 0Hz, 64 frequency hopping points are used which are uniformly distributed in a range of ± 40.96MHz, and the frequency hopping patterns are 8 hops and 64 hops.

8. The miniaturized zero-if fast frequency hopping radio according to claim 1, wherein the initial zero-if hybrid spread spectrum signal uses a 1024-point spreading ratio, BPSK modulation and square wave forming, the transmission data includes a frame header and a data segment, the oversampling factor is 96, and the spreading gain is 46dB in a 64-hop frequency hopping pattern.

9. The miniaturized zero-if fast frequency hopping radio as claimed in claim 1, wherein the center frequency of the initial rf hybrid spread spectrum analog signal is 15.72864 GHz.

10. The miniaturized zero-IF fast frequency hopping radio as claimed in claim 5, wherein said first high speed interface and said second high speed interface use a high speed serial interface JESD 204B.

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