CN103713279B - A kind of multi-channel synchronization excitation source system - Google Patents
A kind of multi-channel synchronization excitation source system Download PDFInfo
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- CN103713279B CN103713279B CN201410006443.1A CN201410006443A CN103713279B CN 103713279 B CN103713279 B CN 103713279B CN 201410006443 A CN201410006443 A CN 201410006443A CN 103713279 B CN103713279 B CN 103713279B
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Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/02—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S19/00—Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
- G01S19/01—Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
- G01S19/13—Receivers
- G01S19/24—Acquisition or tracking or demodulation of signals transmitted by the system
- G01S19/25—Acquisition or tracking or demodulation of signals transmitted by the system involving aiding data received from a cooperating element, e.g. assisted GPS
- G01S19/256—Acquisition or tracking or demodulation of signals transmitted by the system involving aiding data received from a cooperating element, e.g. assisted GPS relating to timing, e.g. time of week, code phase, timing offset
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
- G01S13/02—Systems using reflection of radio waves, e.g. primary radar systems; Analogous systems
- G01S2013/0236—Special technical features
- G01S2013/0245—Radar with phased array antenna
Abstract
The present invention provides a kind of Multichannel radar synchronization motivationtheory origin system, including high-precision frequency source system, Multichannel radar signal waveform synthesis system, detection feedback system.High-precision frequency source system provides high-precision reference clock for Multichannel radar signal waveform synthesis system；Multichannel radar signal waveform synthesis system completes being directly synthesized of output radar signal waveform by DDS；The output signal of detection feedback system coupling Multichannel radar signal waveform each passage of synthesis system, the Magnitude Difference between each passage and phase difference value is extracted by a series of algorithm, and it is fed back in radar signal Waveform composition system, Multichannel radar signal waveform system adjusts amplitude and the phase place of each multi-channel output signal in real time according to the difference fed back to, so that being strict same frequently with width homophase between each passage of radar signal waveform of final whole Multichannel radar system output, it namely it is a kind of multichannel synchronization motivationtheory source.
Description
Technical field
The present invention relates in Multichannel radar system the multi-channel synchronization excitation source system of output waveform amplitude, frequency and phase place strict conformance between each passage a kind of.
Background technology
Along with making constant progress of multichannel phased-array technique, the waveform characteristic exported for each passage requires more and more stricter.For Multichannel radar system, the concordance of the amplitude of each passage output waveform, the concordance of frequency, the concordance of phase place is to weigh the important indicator that a Multichannel radar system is good and bad.For the amplitude of output waveform signals of each passage of radar, frequency and phase place will directly affect the Beam synthesis of whole phased array radar system, and the dissatisfactory Multichannel radar system of its concordance even can not work normally.
Traditional multichannel driving source, is mainly used in phased array system.It includes centralized and distributed two kinds.Centralized referring to divides output by merits such as a driving source carry out, trickle difference is had to cause that the characteristic between passage can not be completely the same yet with the length between each passage and material technology etc., thus having influence on amplitude and the phase place of the radar waveform signal of outfan.And distributed refer to that each passage has independent source, it is possible to individually regulate the parameter in each source, thus it is more distributed more flexible and changeable on using, and yet with what be independent between source, is difficult to so that source synchronism output.
Therefore be centralized driving source or distributed driving source all can not the output amplitude of radar signal waveform between each passage of strict guarantee, frequency consistent with phase characteristic.
Summary of the invention
The present invention is directed to the problems referred to above, a kind of multi-channel synchronization excitation source system is provided, this system is to have improved on distributed basis, magnitude-phase characteristics between multichannel radar system transmission channel can be detected and extracts, calculate the amplitude between each passage and phase contrast, and be fed back to source and be adjusted compensating.Be thus able to so that multi-channel system can synchronism output, the normal operation of safeguards system.Additionally, this system also comprises the high-precision frequency source adopting gps signal calibration, in this, as the reference clock of multichannel driving source, greatly improve precision and the degree of stability of whole system.
For solving above-mentioned technical problem, the technical solution used in the present invention is as follows:
A kind of Multichannel radar synchronization motivationtheory origin system, including high-precision frequency source system, Multichannel radar signal waveform synthesis system, detection feedback system；The outfan of high-precision frequency source system is connected with the input of Multichannel radar signal waveform synthesis system, the outfan of Multichannel radar signal waveform synthesis system is connected with the input of detection feedback system by bonder, and the outfan of detection feedback system is connected with the input of Multichannel radar signal waveform synthesis system.
Described high-precision frequency source system includes GPSOEM plate, fpga chip, digital to analog converter, constant temperature crystalline substance
Oscillation body device OCXO, shaping circuit, wave filter；GPSOEM plate is connected with gps antenna, and FPGA is connected with GPSOEM plate, digital to analog converter, shaping circuit respectively, and constant-temperature crystal oscillator OCXO is connected with digital to analog converter, shaping circuit, wave filter respectively；
After gps satellite locking, GPSOEM plate in high-precision frequency source system is produced by the gps satellite signal caught and is exported high-precision pps pulse per second signal, pps pulse per second signal compares the constant-temperature crystal oscillator OCXO local with logical analysis calibration through processing, the output signal of OCXO is linked into fpga chip through shaping circuit feedback, fpga chip is internal is adjusted the output of digital to analog converter to control OCXO by programme-control by pps pulse per second signal, make the sine wave signal reference clock as Multichannel radar signal waveform synthesis system of the 10MHz that OCXO output high accuracy is very high with degree of stability.
Described Multichannel radar signal waveform synthesis system includes USB interface chip, fpga chip, directly frequency
Rate synthesizer DDS chip；USB interface chip, DDS chip are connected with fpga chip respectively；
Fpga chip completes the sequencing contro to DDS chip, and USB interface chip is connected with the USB interface of computer by USB data line；Computer to control the fpga chip in Multichannel radar signal waveform synthesis system, makes the radar signal waveform that the output of DDS chip is required by USB interface writing commands, and the parameter of radar signal waveform includes amplitude, frequency, phase place etc..
Signal conditioning circuit that described detection feedback system includes being sequentially connected with, multi-channel high-speed A D sampling A/D chip,
Fpga chip；Signal conditioning circuit is connected with bonder；
Multi-channel high-speed A in detection feedback system D sampling A/D chip adopt Differential Input, and coupled the output signal of each passage by directional coupler, the output signal of bonder is nursed one's health by signal conditioning circuit；Multi-channel high-speed A signal after D sampling A/D chip collection conditioning, carry out Digital Signal Processing by fpga chip and complete the amplitude difference of signal between each passage and the extraction of phase contrast and be fed back to Multichannel radar signal waveform synthesis system；
Multichannel radar signal wave closes formation system and adjusts amplitude and the phase place of each channel signal that DDS chip exports according to the difference that detection feedback system feeds back in real time, so that final whole Multichannel radar system is stringent synchronization at outfan, it is strict same frequently with width homophase between each passage of radar signal waveform of output, is namely a kind of multichannel synchronization motivationtheory source.
Described multi-channel high-speed A D sampling A/D chip adopt high speed LVDS interface circuit and fpga chip number
According to transmission.
Compared with prior art, the present invention can be provided with the synchronization motivationtheory source of multiplexer channel, can detect the phase amplitude difference of multiplexer channel outfan simultaneously, and any two passage all can be used alone.Can be with width homophase with frequency between each passage of radar signal waveform of the whole Multichannel radar system output of strict guarantee.On frequently with the basis of width homophase, the relative amplitude between each passage, frequency and phase place can also be arbitrarily set, can be more flexible and changeable so that adjusting output.
Accompanying drawing explanation
Fig. 1 is the overall system diagram of the present invention；
Fig. 2 is the working-flow figure of the present invention；
Fig. 3 is the high-precision frequency source system block diagram of the present invention；
Fig. 4 is the Multichannel radar signal waveform synthesis system block diagram of the present invention；
Fig. 5 be the present invention Multichannel radar signal waveform synthesis system in DDS and corresponding peripheral circuit schematic diagram；
Fig. 6 be the present invention Multichannel radar signal waveform synthesis system in the top layer theory diagram of FPGA time series stereodata；
Fig. 7 is the detection feedback system block diagram of the present invention.
Detailed description of the invention
Below in conjunction with the embodiment of accompanying drawing and the synchronization motivationtheory source producing five paths, the present invention is described in further detail.
Referring to Fig. 1, the present invention includes high-precision frequency source system, Multichannel radar signal waveform synthesis system, detection feedback system；The outfan of high-precision frequency source system is connected with the input of Multichannel radar signal waveform synthesis system, the outfan of Multichannel radar signal waveform synthesis system is connected with the input of detection feedback system by bonder, and the outfan of detection feedback system is connected with the input of Multichannel radar signal waveform synthesis system.Connected mode between each system is as shown in Figure 1.The constant-temperature crystal oscillator of high-precision frequency source system gps satellite signal calibration this locality by catching so that the final sine wave signal reference clock as Multichannel radar signal waveform synthesis system exporting high-precision 10MHz.Multichannel radar signal waveform synthesis system completes being directly synthesized and exporting of radar waveform.Detection feedback system gathers the output signal of each passage by bonder, complete the extraction of each channel wave shape parameter information by the algorithm of a series of Digital Signal Processing and feed back to Multichannel radar signal waveform synthesis system and carry out channel compensation, to ensure that final Multichannel radar signaling system is stringent synchronization at outfan, namely with width same frequency homophase between each passage of radar signal waveform of whole Multichannel radar system output.
Fig. 2 is the workflow diagram of whole system.After system electrification, system will lock gps satellite automatically, and computer man-machine interacting operation interface is accomplished by the usb bus bottom DDS that writes direct and controls the function of parameter, so that the radar waveform signal that native system output is required.Bonder coupling output waveshape signal through detection feedback system multi-channel high-speed A D sampling, extraction and the judgement of each channel wave shape parameter (amplitude, phase place) is completed afterwards through a series of Digital Signal Processings, if each channel amplitude phase place is consistent, then Multichannel radar signal waveform synthesis system output signal；If each channel amplitude phase place is inconsistent, then respectively each paths is carried out calibration of amplitude and phase, and updates the corresponding control word of DDS.Final Multichannel radar signaling system is stringent synchronization at outfan.
Native system can also arbitrarily arrange the relative amplitude between each passage, frequency and phase place on frequently with the basis of width homophase, so that output radar signal waveform is more flexible and changeable.
Fig. 3 is the system block diagram of high-precision frequency source system in native system, high-precision frequency source system produces pps pulse per second signal accurately by the gps satellite signal caught and compares the constant-temperature crystal oscillator OCXO local with logical analysis calibration, the 10MHz reference clock that output accuracy and degree of stability are very high through a series of process.
High-precision frequency source system includes GPSOEM plate, fpga chip, digital to analog converter, constant-temperature crystal oscillator OCXO, shaping circuit, wave filter；GPSOEM plate is connected with gps antenna, and FPGA is connected with GPSOEM plate, digital to analog converter, shaping circuit respectively, and constant-temperature crystal oscillator OCXO is connected with digital to analog converter, shaping circuit, wave filter respectively；
After gps satellite locking, GPSOEM plate in high-precision frequency source system is produced by the gps satellite signal caught and is exported high-precision pps pulse per second signal, pps pulse per second signal compares the constant-temperature crystal oscillator OCXO local with logical analysis calibration through processing, the output signal of OCXO is linked into fpga chip through shaping circuit feedback, fpga chip is internal is adjusted the output of digital to analog converter to control OCXO by programme-control by pps pulse per second signal, make the sine wave signal reference clock as Multichannel radar signal waveform synthesis system of the 10MHz that OCXO output high accuracy is very high with degree of stability.
Fig. 4 is native system Multichannel radar signal waveform synthesis system block diagram, can directly control the various required radar waveform signal of DDS output by usb bus.
Multichannel radar signal waveform synthesis system includes USB interface chip, fpga chip, direct synthesizer DDS chip；USB interface chip, DDS chip are connected with fpga chip respectively；Fpga chip completes the sequencing contro to DDS chip, and USB interface chip is connected with the USB interface of computer by USB data line；Computer controls the fpga chip in Multichannel radar signal waveform synthesis system by USB interface, makes the radar signal waveform that the output of DDS chip is required.
Fig. 5 be the present invention Multichannel radar signal waveform synthesis system in DDS and rear class amplify the peripheral circuit schematic diagrams such as filtering, figure is some passage in multichannel, other passages are similar with it.
Fig. 6 be the present invention Multichannel radar signal waveform synthesis system in the top layer theory diagram of FPGA time series stereodata.
Fig. 7 is the detection feedback system block diagram of the present invention, the waveshape signal of each passage output is coupled by bonder, then through high speed A D sampling, a series of Digital Signal Processing is completed inside FPGA, extracting the characterisitic parameter of each passage and be fed back to Multichannel radar waveshape signal synthesis system, adjusting between each passage of radar signal waveform that output makes whole Multichannel radar system export is strictly with width same frequency homophase.
Signal conditioning circuit that detection feedback system includes being sequentially connected with, multi-channel high-speed A D sampling A/D chip, fpga chip；Signal conditioning circuit is connected with bonder；Multi-channel high-speed A in detection feedback system D sampling A/D chip adopt Differential Input, and by directional coupler coupling channel signal, the output signal of bonder is nursed one's health by signal conditioning circuit；Multi-channel high-speed A D sampling A/D chip collection conditioning after signal, carry out Digital Signal Processing by fpga chip complete the amplitude difference of signal between each passage and the extraction of phase contrast and be fed back to Multichannel radar signal waveform synthesis system, Multichannel radar signal wave closes formation system and adjusts amplitude and the phase place of each multi-channel output signal according to the difference fed back in real time, so that being strict same frequently with width homophase between each passage of radar signal waveform of final whole Multichannel radar system output, it namely it is a kind of multichannel synchronization motivationtheory source.
Claims (2)
1. a Multichannel radar synchronization motivationtheory origin system, it is characterised in that: include high-precision frequency source system, Multichannel radar signal waveform synthesis system, detection feedback system；The outfan of high-precision frequency source system is connected with the input of Multichannel radar signal waveform synthesis system, the outfan of Multichannel radar signal waveform synthesis system is connected with the input of detection feedback system by bonder, and the outfan of detection feedback system is connected with the input of Multichannel radar signal waveform synthesis system；
Described high-precision frequency source system includes GPSOEM plate, the first fpga chip, digital to analog converter, constant-temperature crystal oscillator OCXO, shaping circuit, wave filter；GPSOEM plate is connected with gps antenna, and the first fpga chip is connected with GPSOEM plate, digital to analog converter, shaping circuit respectively, and constant-temperature crystal oscillator OCXO is connected with digital to analog converter, shaping circuit, wave filter respectively；
After gps satellite locking, GPSOEM plate in high-precision frequency source system is produced by the gps satellite signal caught and is exported high-precision pps pulse per second signal, pps pulse per second signal compares the constant-temperature crystal oscillator OCXO local with logical analysis calibration through processing, the output signal of OCXO is linked into the first fpga chip through shaping circuit feedback, first fpga chip is internal is adjusted the output of digital to analog converter to control OCXO by programme-control by pps pulse per second signal, make the sine wave signal reference clock as Multichannel radar signal waveform synthesis system of the 10MHz that OCXO output high accuracy is very high with degree of stability；
Described Multichannel radar signal waveform synthesis system includes USB interface chip, the second fpga chip, direct synthesizer DDS chip；USB interface chip, DDS chip are connected with the second fpga chip respectively；Second fpga chip completes the sequencing contro to DDS chip, and USB interface chip is connected with the USB interface of computer by USB data line；
Computer controls the second fpga chip in Multichannel radar signal waveform synthesis system by USB interface, makes the radar signal waveform that the output of DDS chip is required；
Signal conditioning circuit that described detection feedback system includes being sequentially connected with, multi-channel high-speed A D sampling A/D chip, the 3rd fpga chip；Signal conditioning circuit is connected with bonder；
Multi-channel high-speed A in detection feedback system D sampling A/D chip adopt Differential Input, and by directional coupler coupling channel signal, the output signal of bonder is nursed one's health by signal conditioning circuit；Multi-channel high-speed A D sampling A/D chip collection conditioning after signal, carry out Digital Signal Processing by the 3rd fpga chip complete the amplitude difference of signal between each passage and the extraction of phase contrast and be fed back to Multichannel radar signal waveform synthesis system, Multichannel radar signal wave closes formation system and adjusts amplitude and the phase place of each multi-channel output signal according to the difference fed back in real time, so that being strict same frequently with width homophase between each passage of radar signal waveform of final whole Multichannel radar system output, it namely it is a kind of multichannel synchronization motivationtheory source.
2. a kind of Multichannel radar synchronization motivationtheory origin system according to claim 1, it is characterised in that: described multi-channel high-speed A D sampling A/D chip adopt high speed LVDS interface circuit and the 3rd fpga chip to carry out data transmission.
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| DE102016202112A1 (en) * | 2016-02-12 | 2017-08-17 | Robert Bosch Gmbh | Radar sensor for driver assistance systems in motor vehicles |
| CN108111243B (en) * | 2016-11-25 | 2020-08-04 | 南京中兴软件有限责任公司 | Clock transmission system and corresponding clock synchronization processing method and device |
| CN106612151A (en) * | 2016-12-12 | 2017-05-03 | 武汉滨湖电子有限责任公司 | Device and synchronization method for synchronous output between multichannel DDSs |
| CN107097975B (en) * | 2017-01-06 | 2020-03-24 | 北京航空航天大学 | Multi-signal feedback loading decoupling method and device for structure test system |
| CN107121586A (en) * | 2017-05-04 | 2017-09-01 | 吉林大学 | A kind of pair of Phase Lock Technique 20Hz ~ 20kHz multiple-frequency signal amplitude-phase detects distributed system in real time |
| CN107705253B (en) * | 2017-10-26 | 2021-05-04 | 中国科学院长春光学精密机械与物理研究所 | Method and device for generating video excitation source |
| CN108614271B (en) * | 2018-07-06 | 2023-10-20 | 中国计量大学 | Multichannel ultrasonic wave arbitrary waveform signal generator with feedback correction |
| CN109683137B (en) * | 2018-12-24 | 2022-10-21 | 中国电子科技集团公司第二十研究所 | Multi-channel synchronization method applied to phased array radar |
| CN112067004B (en) * | 2020-09-16 | 2023-03-28 | 上海商汤临港智能科技有限公司 | Time domain synchronization method and device of automatic driving system |
| CN113740809A (en) * | 2021-09-10 | 2021-12-03 | 中国电波传播研究所（中国电子科技集团公司第二十二研究所） | Multi-channel extensible broadband excitation generation device and method |
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