Radar microwave signal optical fiber transmission equipment

Abstract

A radar microwave signal optical fiber transmission device comprises a microwave signal modulation module, an optical fiber signal demodulation module, a radiation horn, an optical fiber assembly and a power supply module. The signal output end of the microwave signal modulation module is connected with the signal input end of the optical fiber signal demodulation module through the optical fiber assembly, the signal output end of the optical fiber signal demodulation module is connected with the radiation horn, the radiation horn is aligned with the radar receiving antenna for radiation, and the signal output end of the radiation horn is further connected with the microwave signal modulation module. The microwave signal modulation module, the optical fiber signal demodulation module and the radiation horn are electrically connected with the power supply module respectively; the device solves the problem of low efficiency of radar test equipment, and has the characteristics of convenience in equipment debugging, high test efficiency and controllable microwave signal gain of the equipment.

Description

Technical Field

[0001] The utility model relates to the technical field of radar testing, in particular to optical fiber transmission equipment for radar microwave signals. Background Art

[0002] Radar microwave signal optical fiber transmission equipment is radar debugging equipment, used for radar transmission, receiving test calibration signals to the far-field radiation horn, radiating for radar receiving test calibration, or feeding back the radar transmission signal received by the far-field test horn to the radar for test processing, and detecting the radar's transmission-related performance.

[0003] During the debugging process of existing transmission equipment, various instruments are used to build a test platform, such as signal source, spectrum analyzer, function generator, etc., and the corresponding trigger signal needs to be led from the radar end to the instrument. During the test, the signal transmitter is generally far and high from the radar, and all kinds of instruments need to be moved. There are also many various quote lines led from the radar end, which is very inconvenient for field debugging. During the debugging process, a large amount of manpower is also required to operate the radar end and the signal transmitter. It is impossible to achieve long-distance optical transmission. At the same time, there is no gain adjustment function during the transmission process, which makes the configuration of the test more difficult.

[0004] The above problems make the entire radar test equipment inefficient and unable to meet radar test requirements. Summary of the invention

[0005] In order to solve the problem of low efficiency of radar testing equipment in the prior art, the utility model proposes radar microwave signal optical fiber transmission equipment.

[0006] Radar microwave signal optical fiber transmission equipment, including microwave signal modulation module, optical fiber signal demodulation module, radiation horn, optical fiber assembly and power supply module;

[0007] The signal output end of the microwave signal modulation module is connected to the signal input end of the optical fiber signal demodulation module through an optical fiber component, the signal output end of the optical fiber signal demodulation module is connected to a radiation horn, the radiation horn is aimed at the radar receiving antenna for radiation, and the signal output end of the radiation horn is also connected to the microwave signal modulation module;

[0008] The microwave signal modulation module, the optical fiber signal demodulation module and the radiation horn are electrically connected to the power supply module respectively.

[0009] The microwave signal modulation module includes a first radio frequency amplification and attenuation adjustable module and a first photoelectric conversion component; the optical fiber signal demodulation module includes a second photoelectric conversion component and a second radio frequency amplification and attenuation adjustable module;

[0010] The input end of the first RF amplification and attenuation adjustable module is connected to the RF input port, the output end of the first RF amplification and attenuation adjustable module is connected to the input end of the first photoelectric conversion component, the output end of the first photoelectric conversion component is connected to the input end of the second photoelectric conversion component through an optical fiber component, the output end of the second photoelectric conversion component is connected to the input end of the second RF amplification and attenuation adjustable module, and the output end of the second RF amplification and attenuation adjustable module is connected to the RF output port.

[0011] The microwave signal modulation module also includes a first single chip microcomputer, which is used to control the first radio frequency amplification and attenuation adjustable module. The first single chip microcomputer is provided with a gain adjustment knob.

[0012] The optical fiber signal demodulation module also includes a second single chip microcomputer, which is used to control the second radio frequency amplification and attenuation adjustable module, and the second single chip microcomputer is provided with a gain adjustment knob.

[0013] The optical fiber assembly includes an armored optical fiber, an adapter and a retractable rack. The armored optical fiber is equipped with a plug, and the armored optical fibers are connected to each other through the plug and the adapter; the retractable rack is used for retracting and releasing the optical fiber.

[0014] The armored optical fiber configuration plug is a J599A8 plug and / or a FC / APC plug.

[0015] The power supply module can select an external AC220V alternating current power supply, an external DC24V direct current power supply or a built-in lithium battery.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] The utility model radar microwave signal optical fiber transmission equipment comprises a transmission equipment composed of a microwave signal modulation module and an optical fiber signal demodulation module, which can realize radar reception detection calibration, radar transmission detection calibration and radar distance calibration, and the equipment has convenient equipment debugging and high test efficiency. At the same time, the microwave signal gain of the equipment is controllable, various losses can be compensated, and a suitable signal amplitude can be output. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the overall structure of the utility model.

[0019] Figure 2 This is a schematic diagram of the specific connection between the microwave signal modulation module and the optical fiber signal demodulation module of the utility model.

[0020] Figure 3 This is a schematic diagram of the radar receiving detection calibration mode used in the present invention.

[0021] Figure 4 This is a schematic diagram of the radar emission detection calibration mode used in the present invention.

[0022] Figure 5 This is a schematic diagram of the radar distance calibration mode used in the utility model.

[0023] Figure 6 This is a random vibration spectrum density curve of the optical fiber transmission device of the utility model.

[0024] In the figure: 101, a first RF amplification and attenuation adjustable module; 102, a first photoelectric conversion component; 103, a first single-chip microcomputer; 201, a second photoelectric conversion component; 202, a second RF amplification and attenuation adjustable module; 203, a second single-chip microcomputer. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0026] like Figure 1 As shown, the radar microwave signal optical fiber transmission device includes a microwave signal modulation module, an optical fiber signal demodulation module, a radiation horn, an optical fiber assembly and a power supply module. The signal output end of the microwave signal modulation module is connected to the signal input end of the optical fiber signal demodulation module through the optical fiber assembly, the signal output end of the optical fiber signal demodulation module is connected to the radiation horn, the radiation horn is aimed at the radar receiving antenna for radiation, and the signal output end of the radiation horn is also connected to the microwave signal modulation module; the microwave signal modulation module, the optical fiber signal demodulation module and the radiation horn are electrically connected to the power supply module respectively.

[0027] like Figure 2 As shown, the microwave signal modulation module includes a first RF amplification and attenuation adjustable module 101 and a first photoelectric conversion component 102; the optical fiber signal demodulation module includes a second photoelectric conversion component 201 and a second RF amplification and attenuation adjustable module 202; the first photoelectric conversion component 102 is used to modulate the detection calibration signal or coupling signal output by the radar into an optical signal, and the second photoelectric conversion component 201 is used to demodulate the optical signal into a microwave signal; the first RF amplification and attenuation adjustable module 101 and the second RF amplification and attenuation adjustable module 202 are used to realize microwave signal gain control.

[0028] The input end of the first RF amplification and attenuation adjustable module 101 is connected to the RF input port, the output end of the first RF amplification and attenuation adjustable module 101 is connected to the input end of the first photoelectric conversion component 102, the output end of the first photoelectric conversion component 102 is connected to the input end of the second photoelectric conversion component through an optical fiber component, the output end of the second photoelectric conversion component 201 is connected to the input end of the second RF amplification and attenuation adjustable module 202, and the output end of the second RF amplification and attenuation adjustable module 202 is connected to the RF output port.

[0029] The microwave signal modulation module also includes a first single-chip microcomputer 103. The first single-chip microcomputer 103 is provided with a gain adjustment knob. The gain adjustment knob is used for regulation and is divided into two parts, one part is X ten-fold regulation and the other part is X one-fold regulation. The X ten-fold regulation is divided into: -X, 0, 1X, 2X, 3X, 4X, 5X, which respectively represent attenuation of 10dB, increase of 0dB, increase of 10dB, increase of 20dB, increase of 30dB, increase of 40dB, increase of 50dB; the X one-fold regulation is divided into: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, which respectively represent increase of 0dB, increase of 1dB, increase of 2dB, increase of 3dB, increase of 4dB, increase of 5dB, increase of 6dB, increase of 7dB, increase of 8dB, increase of 9dB.

[0030] The optical fiber signal demodulation module also includes a second single-chip microcomputer 203, which is provided with a gain adjustment knob. The gain adjustment knob is used for regulation and is divided into two parts, one part is X ten-fold regulation and the other part is X one-fold regulation. The X ten-fold regulation is divided into: 0, 1X, 2X, 3X, 4X, 5X, 6X, which respectively represent attenuation of 0dB, attenuation of 10dB, attenuation of 20dB, attenuation of 30dB, attenuation of 40dB, attenuation of 50dB, attenuation of 60dB; the X one-fold regulation is divided into: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, which respectively represent attenuation of 0dB, attenuation of 1dB, attenuation of 2dB, attenuation of 3dB, attenuation of 4dB, attenuation of 5dB, attenuation of 6dB, attenuation of 7dB, attenuation of 8dB, attenuation of 9dB.

[0031] The microwave signal modulation module is used to modulate the detection calibration signal or coupling signal output by the radar into an optical signal, and transmit the optical signal to the optical fiber signal demodulation module. The microwave signal modulation module is used to modulate the radar transmission signal received by the radiation horn into an optical signal, and transmit the optical signal to the optical fiber signal demodulation module; wherein, the operating frequency range is 2GHz to 16GHz; the maximum value of the input signal is ≤20dBm, and 10dBm can be selected typically, and the input large signal (20dBm) can be limited to protect the amplitude; the linear power range of the RF signal input is -60dBm to 10dBm; the gain adjustment range is -10dB to +50dB, which can optimize the linearity and signal-to-noise ratio; the gain adjustment method adopts the step adjustment of the gain adjustment knob, the step amount is 1dB, and the attenuation accuracy is ±(0.5+5%ATT).

[0032] The optical fiber signal demodulation module is used to demodulate the optical signal into a microwave signal, and transmit the microwave signal to the detection channel of the radar through a radiation horn; the operating frequency of the optical fiber signal demodulation module and the microwave signal modulation module are kept at the same frequency, so that the operating frequency range is between 2GHz and 16GHz, meeting the attenuation requirements of long-distance transmission; the maximum value of the output microwave signal is ≤10dBm, and 0dBm can be selected typically; the gain adjustment range is between -60dB and 0dB, which can compensate for various losses and achieve the output of a suitable signal amplitude; the gain adjustment method also adopts a gain adjustment knob step adjustment, the step amount is 1dB, and the attenuation accuracy is ±(0.5+5%ATT).

[0033] The microwave signal modulation module and the optical fiber signal demodulation module are both installed on the transmission equipment through the adapter, and the two adapters are provided with the same external installation interface. The microwave signal modulation module and the optical fiber signal demodulation module with the above structural parameters can ensure that the weight is controlled below 6.5KG, and the power consumption of a single module is less than or equal to 50W, which meets the requirements of portable use conditions.

[0034] In addition, the outer surface of the entire transmission equipment can be spray-coated in military green color, and the color code is preferably GY06.

[0035] The matching optical fiber components use protective armored optical fiber, and the lengths between optical fibers can be connected through the matching adapters; in order to meet the requirements of long-term outdoor installation, the optical fiber can also be equipped with a retractable rack. The length of the armored optical fiber can be selected according to the distance, such as the conventional 150m, 200m, 500m optical fiber series length, and 3m, 2m, etc. can also be selected to meet the requirements of long distances and convenient switching.

[0036] As a preferred implementation, 150m, 200m, and 500m optical fibers use two-core field optical cables, with 1 core in use and 1 core as backup; 1 150m armored optical fiber, 1 200m armored optical fiber, and 4 500m armored optical fibers. All optical fibers have J599A8 two-core plugs at both ends and are equipped with a cable retractable rack; 2 2m optical cables, one end with a J599A8 plug and the other end with an FC / APC plug; 4 3m optical cables, both ends with FC / APC plugs.

[0037] In actual use, you can freely choose a series of optical fibers of different lengths and connect them with appropriate adapters to complete long-distance transmission.

[0038] The power supply module adopts the following three power supply modes:

[0039] Method 1: External AC220V AC power supply, using 50Hz, AC220V±10% AC power supply, and AC power supply through AC input lithium battery charging adapter;

[0040] Method 2: External DC24V power supply, using DC22V-DC30V power supply, typical value DC28V, using circular connector as charging interface, and providing 2 matching plugs;

[0041] Method 3: Built-in lithium battery, the lithium battery charging interface uses a circular connector and provides 2 matching plugs; an external charging adapter is provided, and the battery life after a full charge is not less than 4 hours, which meets the working time of the device.

[0042] In addition, the microwave signal input interface and the microwave signal output interface both use stainless steel SMA connectors, 50 ohms; the radiation horn interface also uses stainless steel SMA connectors, 50 ohms.

[0043] Radar microwave signal optical fiber transmission equipment has a band passband selection function, and the band pass filter bands are allocated as follows: S band: 2-4G; C band: 4-8G; X band: 8-12.5G; Ku band: 12.5-16G. The above passband selection function can effectively reduce out-of-band noise.

[0044] Corresponding to the above functional module units, the panel of the entire radar microwave signal optical fiber transmission equipment can be configured as follows:

[0045] The panel power selection switch has three power selection modes; the panel input and output microwave signal connector; the panel input and output fiber optic signal connector; the panel gain adjustment knob; the panel microwave signal band selection, the band selection is achieved through the coaxial filter, the coaxial filter is best placed inside the tooling, and the change is made by replacing the external cable interface; the front panel has light, no light, fault, battery level and power indication.

[0046] Three working modes of radar microwave signal optical fiber transmission equipment:

[0047] 1) Radar receiving detection calibration mode

[0048] Radar microwave signal optical fiber transmission equipment is used for radar receiving detection calibration functional connection diagram as shown below Figure 3 As shown:

[0049] The radar frequency synthesizer outputs a detection calibration signal that is consistent with the waveform of the transmission excitation signal and has adjustable amplitude and delay. The signal is modulated into an optical signal by a microwave signal modulation module, and remotely transmitted through an optical fiber to a distance that meets the far-field conditions of the radar test. The signal is demodulated into a microwave signal by an optical fiber signal demodulation module. The amplitude of this microwave signal has an adjustable capability of 0-60dB and is used to simulate the amplitude change of the target radar echo. The signal is radiated toward the radar receiving antenna through a radiation horn. The echo signal can be used for: (1) receiving an external correction signal source; (2) receiving an azimuth test signal source; (3) performing fault diagnosis by comparing the amplitudes of the received signals of different receiving units; and (4) simulating an external moving target of the radar.

[0050] 2) Radar emission detection calibration mode

[0051] Radar microwave signal optical fiber transmission equipment is used for radar emission detection and calibration. Figure 4 As shown:

[0052] The radar normally transmits a signal, which is received by a radiation horn at a distance that meets the radar far-field test conditions. The received signal is modulated into an optical signal by a microwave signal modulation device. The amplitude of this microwave signal has the ability to adjust from 0 to +60 dB. It is remotely transmitted back to the optical fiber signal demodulation module through the optical fiber, and demodulated into a microwave signal by the optical fiber signal demodulation module for transmitting signal amplitude and phase detection. The echo signal can be used for: (1) transmitting an external source correction echo; (2) transmitting an azimuth test echo; (3) performing fault diagnosis by comparing the receiving signal amplitudes of individual transmitting units in turn.

[0053] 3) Radar distance calibration mode

[0054] Radar microwave signal optical fiber transmission equipment is used for radar distance calibration. Figure 5 As shown:

[0055] The transmitting excitation signal (0dB) coupled output by the radar transmitting front-stage module or the transmitting excitation signal of the radar normally transmitted and received by the radiation horn is modulated into an optical signal by the microwave signal modulation module, and remotely transmitted to a distance that meets the far-field conditions of the radar test through the optical fiber, demodulated into a microwave signal by the optical fiber signal demodulation module, and radiated by the radiation horn aimed at the radar receiving antenna. By measuring the distance L1 between the radiation horn and the radar, the transmission delay of the radar microwave signal optical fiber transmission equipment is calibrated to be consistent with T1; the actual measurement distance of the radar is L2, and the radar distance correction value can be obtained by calculation: L=L2-L1-T1*150, thereby completing the radar distance calibration.

[0056] In addition, the entire device should be treated with three anti-corrosion treatments to meet the requirements of industrial-grade product design:

[0057] High temperature storage: +60℃; High temperature working: +55℃;

[0058] Low temperature storage: -30℃; Low temperature working: -20℃;

[0059] Temperature 30℃, no condensation; relative humidity 95±3%;

[0060] Random vibration is performed according to the spectral density curve setting. The vibration direction is along the x, y, and z axes (vertical direction). The vibration time in each direction is 5 minutes. The random vibration spectral density curve is shown in Figure 6 As shown, the frequency range is 5-20Hz, the power spectrum density is +3db / Oct, the frequency range is 20-200Hz, the power spectrum density is 0.03, and the frequency range is 200-500Hz, the power spectrum density is -3db / Oct.

[0061] The utility model adopts a transmission device composed of a microwave signal modulation module and an optical fiber signal demodulation module to realize long-distance optical transmission of a 2GHz to 16GHz microwave signal, accurately calibrate the long optical fiber transmission delay, and the total transmission delay accuracy is ≤5nS (SMA port to SMA port), and the equivalent total transmission gain is ≥0dB (when the gain adjustment of the microwave signal modulation device and the optical fiber demodulation device are both 0dB), which can be used for radar distance calibration and realize long-distance optical transmission. At the same time, it has a gain adjustment function, which can compensate for various losses and output a suitable signal amplitude; in addition, the device has a band passband selection function, which makes the noise coefficient of the transmission device deteriorate ≤50dB, reduces out-of-band noise, and makes the test operation environment more pleasant.

Claims

1. Radar microwave signal optical fiber transmission equipment, characterized in that: It includes a microwave signal modulation module, an optical fiber signal demodulation module, a radiation horn, an optical fiber assembly and a power supply module; The signal output end of the microwave signal modulation module is connected to the signal input end of the optical fiber signal demodulation module through an optical fiber assembly, the signal output end of the optical fiber signal demodulation module is connected to a radiation horn, the radiation horn is aimed at the radar receiving antenna for radiation, and the signal output end of the radiation horn is also connected to the microwave signal modulation module; The microwave signal modulation module, the optical fiber signal demodulation module and the radiation horn are electrically connected to the power supply module respectively.

2. The radar microwave signal optical fiber transmission device according to claim 1, characterized in that: The microwave signal modulation module comprises a first radio frequency amplification and attenuation adjustable module (101) and a first photoelectric conversion component (102); the optical fiber signal demodulation module comprises a second photoelectric conversion component (201) and a second radio frequency amplification and attenuation adjustable module (202); The input end of the first radio frequency adjustable amplification and attenuation module (101) is connected to the radio frequency input port, the output end of the first radio frequency adjustable amplification and attenuation module (101) is connected to the input end of the first photoelectric conversion component (102), the output end of the first photoelectric conversion component (102) is connected to the input end of the second photoelectric conversion component (201) via an optical fiber component, the output end of the second photoelectric conversion component (201) is connected to the input end of the second radio frequency adjustable amplification and attenuation module (202), and the output end of the second radio frequency adjustable amplification and attenuation module (202) is connected to the radio frequency output port.

3. The radar microwave signal optical fiber transmission device according to claim 2, characterized in that: The microwave signal modulation module further comprises a first single chip microcomputer (103), the first single chip microcomputer (103) being used to control the first radio frequency amplification and attenuation adjustable module (101), and the first single chip microcomputer (103) being provided with a gain adjustment knob.

4. The radar microwave signal optical fiber transmission device according to claim 1, characterized in that: The optical fiber signal demodulation module further comprises a second single chip microcomputer (203), the second single chip microcomputer (203) is used to control the second radio frequency amplification and attenuation adjustable module (202), and the second single chip microcomputer (203) is provided with a gain adjustment knob.

5. The radar microwave signal optical fiber transmission device according to claim 1, characterized in that: The optical fiber assembly includes an armored optical fiber, an adapter and a retractable rack. The armored optical fiber is equipped with a plug, and the armored optical fibers are connected to each other through the plug and the adapter; the retractable rack is used for retracting and releasing the optical fiber.

6. The radar microwave signal optical fiber transmission device according to claim 5, characterized in that: The armored optical fiber configuration plug is a J599A8 plug and / or a FC / APC plug.

7. The radar microwave signal optical fiber transmission device according to claim 1, characterized in that: The power supply module can select an external AC220V alternating current power supply, an external DC24V direct current power supply or a built-in lithium battery.

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