A microwave photon radar detection and frequency measurement method and integrated device

Abstract

The present invention discloses a microwave photon radar detection and frequency measurement method and its integrated device. It includes: converting an adjustable optical signal into a linear swept frequency electrical signal; using a first distributor to divide the linear swept frequency electrical signal into a test signal; using a second distributor to divide the test signal into a reference signal and a detection signal; using the detection signal to detect, and obtaining an echo signal after being reflected by a target object; inputting the reference signal, the test signal and the echo signal into a dual-polarization dual-drive Mach-Zehnder modulator for processing, and outputting a first polarization signal and a second polarization signal; and then processing to obtain the position information and frequency of the target object. When the present invention is used to measure frequency, an adjustable optical signal is used to change the range of the swept frequency signal and the frequency measurement range. Only one dual-polarization dual-drive Mach-Zehnder modulator is used to simultaneously perform radar detection and frequency measurement. When the present invention is used for radar identification, no additional radio frequency source is required, and it has super flexible adjustability.

Description

Technical Field

[0001] The present invention relates to the field of microwave photon frequency measurement and radar technology, and in particular to a microwave photon radar detection and frequency measurement method and an integrated device thereof. Background Art

[0002] Microwave frequency measurement plays an indispensable role in modern electronic warfare, radar and wireless communication systems. Traditional electrical frequency measurement methods are limited by the electronic components they use, and their measurement speed and measurement bandwidth are often limited and affected by electromagnetic interference. Microwave photonic technology has many advantages such as large instantaneous bandwidth, low transmission loss, and anti-electromagnetic interference, which opens up new ideas for high-performance microwave frequency measurement. As a well-known microwave photon frequency measurement method, the swept frequency heterodyne frequency measurement method uses a linear swept frequency signal as a signal source to mix with the signal to be measured. For frequency measurement, the larger the bandwidth of the linear swept frequency signal used, the larger the measurement range that can be achieved. Similarly, for radar detection, its range detection resolution can also be improved by a large-bandwidth linear swept frequency signal. The linear swept frequency signals used in radar detection in the past are often generated by radio frequency sources and only work effectively in a pre-designed specific bandwidth band, which will limit the reconfigurability of the radar, and radars without radio frequency sources are rarely reported. The frequency modulated signal generated by light injection into a semiconductor laser can generate an adjustable signal with a frequency range from several GHz to over 100 GHz without the need for an external RF source, which will greatly improve the performance of frequency measurement systems and radar detection systems.

[0003] At present, there is a microwave photon frequency measurement method based on microwave photon frequency doubling and mixing. The microwave photon processing technology of frequency doubling and mixing is used. When the generated optical signal is converted into an electrical signal, the measurement range is limited. The enhancement range requires an arbitrary waveform generator with a large sampling rate, which has a high production cost. In addition, multiple Mach-Zehnder modulators are used, which is too expensive. In the prior art, a programmable optical filter is used to select the sideband containing the frequency component of the signal to be measured. In fact, the frequency of the signal to be measured is unknown. Using this filter to select the sideband will cause problems, and there is a certain possibility of limiting the measurement bandwidth, affecting the subsequent measurement effect.

[0004] From the above, it can be seen that how to improve the accuracy of radar detection and frequency measurement is a problem that needs to be solved at present. Summary of the invention

[0005] The purpose of the present invention is to provide a microwave photon radar detection and frequency measurement method and an integrated device thereof to solve the problems in the prior art of limited measurement range, low accuracy and high production cost.

[0006] In order to solve the above technical problems, the present invention provides a microwave photon radar detection and frequency measurement method and an integrated device thereof, comprising: converting an adjustable optical signal into a linear frequency sweeping electrical signal;

[0007] Allocating the linear frequency sweeping electrical signal into a feedback signal and a test signal;

[0008] Allocating the test signal into a reference signal and a probe signal;

[0009] Using the detection signal to perform radar detection, and obtaining an echo signal after being reflected by a target object;

[0010] receiving a frequency test signal using a frequency receiving antenna;

[0011] Inputting the reference signal, the frequency measurement signal and the echo signal into a dual-polarization dual-drive Mach-Zehnder modulator for processing, and outputting a first polarization signal and a second polarization signal;

[0012] De-chirping the first polarization state signal to obtain an intermediate frequency signal, extracting characteristic information of the target object from the intermediate frequency signal, and obtaining position information of the target object;

[0013] The second polarization state signal is frequency-converted to obtain a linear frequency sweep signal, a plurality of pulses of the linear frequency sweep signal are calculated, and the frequency to be measured is obtained by pulse time difference mapping.

[0014] Preferably, converting the adjustable optical signal into a linear frequency-sweeping electrical signal comprises:

[0015] generating the adjustable optical signal using a master laser;

[0016] The adjustable optical signal is input into a slave laser, and the slave laser is used to process and output the linear frequency-sweeping electrical signal.

[0017] Preferably, the detuning frequency of the master laser and the slave laser is f i =|f ML -f SL |;

[0018] Among them, f ML is the frequency of the optical signal output by the master laser, f SL is the frequency of the optical signal output from the laser.

[0019] Preferably, the using the detection signal to perform radar detection and obtaining an echo signal through reflection from a target object comprises:

[0020] The detection signal is input into a transmitting antenna and transmitted into free space, and an echo signal reflected by the target object is obtained by a receiving antenna.

[0021] Preferably, the receiving the frequency test signal by using a frequency receiving device comprises:

[0022] The signal received by the frequency receiving antenna is input into the amplifier for amplification to obtain the frequency test signal of the target object.

[0023] Preferably, the expression of the reference signal is:

[0024]

[0025] Wherein, V1 is the amplitude, j is the imaginary unit, f2 is the upper limit of the sweep range, B is the sweep signal bandwidth, and T is the period.

[0026] Preferably, the step of inputting the reference signal, the frequency test signal and the echo signal into a dual-polarization dual-drive Mach-Zehnder modulator for processing, and outputting a first polarization signal and a second polarization signal comprises:

[0027] Inputting the reference signal and the echo signal into the upper arm of the dual-polarization dual-drive Mach-Zehnder modulator, driving the upper arm of the dual-polarization dual-drive Mach-Zehnder modulator, and outputting the first polarization state signal;

[0028] The reference signal and the frequency test signal are input into the lower arm of the dual-polarization dual-drive Mach-Zehnder modulator to drive the lower arm of the dual-polarization dual-drive Mach-Zehnder modulator and output the second polarization state signal.

[0029] Preferably, de-chirping the first polarization state signal to obtain an intermediate frequency signal, extracting characteristic information of the target object from the intermediate frequency signal, and obtaining position information of the target object comprises:

[0030] Inputting the first polarization state signal into a polarization beam splitter for frequency conversion, and outputting the intermediate frequency signal;

[0031] A low-pass filter is used to filter out high-frequency harmonics of the intermediate frequency signal, extract the characteristic value of the target object, and obtain the position information of the target object.

[0032] Preferably, the step of converting the second polarization state signal to obtain a linear frequency sweep signal, calculating a plurality of pulses of the linear frequency sweep signal, and obtaining the frequency to be measured by pulse time difference mapping comprises:

[0033] Inputting the second polarization state signal into the polarization beam splitter for frequency conversion, and outputting a linear frequency sweep signal;

[0034] Inputting the linear frequency sweep signal into an electrical bandpass filter for processing and outputting a plurality of pulse values;

[0035] The frequency to be measured is obtained according to the time difference mapping of the multiple pulse values.

[0036] The present invention also provides a radar detection and frequency measurement device, comprising:

[0037] A photoelectric conversion module, used for converting an adjustable optical signal into a linear frequency-sweeping electrical signal;

[0038] A first distribution module, used for dividing the linear frequency sweeping electrical signal into a feedback signal and a test signal;

[0039] A second allocation module, used for dividing the test signal into a reference signal and a detection signal;

[0040] A radar detection module, used to perform radar detection using the detection signal and obtain an echo signal after being reflected by a target object;

[0041] A frequency measurement module, used for receiving a frequency test signal using a frequency receiving device;

[0042] A centralized processing module, used for inputting the reference signal, the frequency test signal and the echo signal into a dual-polarization dual-drive Mach-Zehnder modulator for processing, and outputting a first polarization signal and a second polarization signal;

[0043] A radar detection information processing module, configured to de-chirp the first polarization state signal to obtain an intermediate frequency signal, extract characteristic information of the target object from the intermediate frequency signal, and obtain position information of the target object;

[0044] The frequency measurement information processing module is used to convert the frequency of the second polarization state signal to obtain a linear frequency sweep signal, calculate multiple pulses of the linear frequency sweep signal, and obtain the frequency to be measured by pulse time difference mapping.

[0045] The present invention provides a microwave photon radar detection and frequency measurement method and an integrated device thereof, which uses an adjustable injection light as a reference light, processes the adjustable optical signal and converts it into a linear swept electrical signal, uses a distributor to distribute it into a detection signal and a reference signal, uses the detection signal for detection, obtains an echo signal, and then uses a dual-polarization dual-drive Mach-Zehnder modulator to realize radar detection and frequency measurement, outputs a first polarization signal and a second polarization signal, and obtains the position information and frequency of the target object according to the first polarization signal and the second polarization signal. The present invention uses an adjustable optical signal to generate a linear swept signal, so the generated double-chirp linear swept signal has the advantages of large swept bandwidth and flexible adjustability, which can reach a swept bandwidth of more than 10 GHz, and adjusting the frequency of the adjustable optical signal and the driving voltage can change the center frequency, bandwidth, frequency band and period of the generated linear swept signal, which not only improves the detection accuracy of the radar, but also improves the measurement bandwidth of the frequency measurement. In the present invention, no additional optical filter is required to select the sideband generated after the signal source to be measured modulates the optical carrier, thereby avoiding the influence of other filters on the measurement bandwidth. In addition, the frequency sweep range of the generated double-chirp linear frequency sweep signal can be changed by adjusting the injection parameters, thereby changing the frequency measurement range. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the embodiments of the present invention or the technical solutions of the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0047] Figure 1 A flowchart of a first specific embodiment of a method for microwave photon radar detection and frequency measurement provided by the present invention;

[0048] Figure 2 A flowchart of a second specific embodiment of a method for microwave photon radar detection and frequency measurement provided by the present invention;

[0049] Figure 3 is the generated double-chirp linear frequency sweep signal;

[0050] Figure 4 This is the schematic diagram for realizing the radar detection function;

[0051] Figure 5 This is the schematic diagram for realizing the frequency measurement function;

[0052] Figure 6 This is the implementation schematic diagram of another measurement range of the frequency measurement function;

[0053] Figure 7 This is a structural block diagram of a microwave photon radar detection and frequency measurement device provided by the present invention. DETAILED DESCRIPTION

[0054] The core of the present invention is to provide a method for radar detection and frequency measurement, which adopts an adjustable optical signal to replace the existing frequency doubling and mixing, thereby increasing the frequency sweep width, improving the radar detection accuracy and the measurement width of the frequency measurement.

[0055] In order to enable those skilled in the art to better understand the scheme of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0056] Please refer to Figure 1 , Figure 1 This is a flow chart of a first specific embodiment of a method for microwave radar detection and frequency measurement provided by the present invention; the specific operation steps are as follows:

[0057] Step S101: converting an adjustable optical signal into a linear frequency-sweeping electrical signal;

[0058] Step S102: allocating the linear frequency sweeping electrical signal into a test signal and a feedback signal;

[0059] Step S103: Allocate the test signal into a reference signal and a detection signal;

[0060] Step S104: performing radar detection using the detection signal, and obtaining an echo signal after being reflected by a target object;

[0061] Step S104: using a frequency receiving device to receive a frequency test signal;

[0062] Step S105: inputting the reference signal, the test signal and the echo signal into a dual-polarization dual-drive Mach-Zehnder modulator for processing, and outputting a first polarization signal and a second polarization signal;

[0063] Step S106: de-chirping the first polarization state signal to obtain an intermediate frequency signal, extracting characteristic information of the target object from the intermediate frequency signal, and obtaining position information of the target object;

[0064] Step S107: frequency-converting the second polarization state signal to obtain a linear frequency sweep signal, calculating a plurality of pulses of the linear frequency sweep signal, and obtaining a frequency to be measured by pulse time difference mapping.

[0065] In this embodiment, the adjustable optical signal is first converted into a linear frequency sweep signal, and no additional RF source is used as the RF signal. Therefore, the generated double-chirp linear frequency sweep signal has the advantages of large frequency sweep bandwidth and flexible adjustability. Then, a distributor is used to distribute the signal, and then a dual-polarization dual-drive Mach-Zehnder modulator is used to process to obtain two polarization signals, and then radar detection information and frequency measurement information are calculated respectively according to the two polarization signals. The present invention uses an adjustable optical signal to generate a linear frequency sweep signal, so the generated double-chirp linear frequency sweep signal has the advantages of large frequency sweep bandwidth and flexible adjustability, and can reach a frequency sweep bandwidth of more than 10 GHz, and adjusting the frequency of the adjustable optical signal and the driving voltage can change the center frequency, bandwidth, frequency band and period of the generated linear frequency sweep signal, which not only improves the detection accuracy of the radar, but also improves the measurement bandwidth of the frequency measurement. In the present invention, no additional optical filter is required to select the sideband generated after the signal source to be measured modulates the optical carrier, thereby avoiding the influence of other filters on the measurement bandwidth.

[0066] Based on the above embodiments, this embodiment describes the specific steps in the above embodiments in detail. Figure 2 , Figure 2 This is a flow chart of a second specific embodiment of a method for microwave photon radar detection and frequency measurement provided by the present invention; the specific operation steps are as follows:

[0067] Step S201: using a main laser to generate an adjustable optical signal;

[0068] Step S202: using a first photodetector to convert the adjustable optical signal into a linear frequency-sweeping electrical signal;

[0069] The injected light provided by the master laser generates an optical signal with adjustable waveform, period and intensity. The optical signal with continuously adjustable light intensity is injected into the slave laser through an optical circulator, and a double-chirp linear frequency-sweeping electrical signal is obtained after photoelectric conversion.

[0070] The central wavelengths of the master laser and the slave laser are both 1550nm±0.5nm.

[0071] The detuning frequency between the master laser and the slave laser is fi = |f ML -f SL |, where f ML is the frequency of the main laser output optical signal, f SL is the frequency of the free-running optical signal output from the laser.

[0072] like Figure 3 As shown, the optical signal output from the laser includes a double-chirped linear frequency-swept optical signal, whose frequency sweep range is from f1 to f2 and then from f2 back to f1 in a single cycle. The frequency sweep bandwidth is B=f2-f1 and the period is T.

[0073] Step S203: using a first distributor to distribute the linear frequency sweep signal into a feedback signal and a test signal;

[0074] The linear frequency sweeping electrical signal is divided into a feedback signal and a test signal by a first power divider, and the feedback signal enters a feedback control module to improve the stability of the system.

[0075] The feedback signal is input into the feedback module and input into the injected light adjustment module to maintain the stability of the system operation.

[0076] Step S204: using a second distributor to divide the test signal into a reference signal and a detection signal;

[0077] The reference signal is further divided by the second power divider into reference signals used by the radar detection function and the frequency measurement function. The reference signal expression is:

[0078]

[0079] Where V1 is the amplitude, j is the imaginary unit, f2 is the upper limit of the sweep range, B is the sweep signal bandwidth, and T is the period.

[0080] Step S205: Detection is performed using the detection signal to obtain a reflected echo signal;

[0081] The detection signal is input to a radar detection device, which includes a first amplifier and a transmitting antenna, a second amplifier and a receiving antenna that are isolated from each other, the first electrical amplifier is used to amplify the detection signal, and the second electrical amplifier is used to amplify the echo signal. The detection signal is input to the transmitting antenna and transmitted to the free space. After being reflected by the target object, the receiving antenna obtains the echo signal reflected by the target object. There is a delay time Δτ between the echo signal and the transmitting signal, so the distance d of the target can be calculated by d=2BΔτ / T. Since the transmitting signal is a linearly swept electrical signal, the distance information of the target object can be obtained by directly calculating the frequency difference between the transmitting signal and the echo signal.

[0082] Step S206: inputting the reference signal and the echo signal into the upper arm of the dual-polarization dual-drive Mach-Zehnder modulator, driving the upper arm of the dual-polarization dual-drive Mach-Zehnder modulator, and outputting a first polarization state signal;

[0083] Step S207: inputting the reference signal and the frequency test signal into the lower arm of the dual-polarization dual-drive Mach-Zehnder modulator, driving the lower arm of the dual-polarization dual-drive Mach-Zehnder modulator, and outputting a second polarization state signal;

[0084] The reference signal, the echo signal and the frequency test signal are inputted into a dual-polarization dual-drive Mach-Zehnder modulator together. The dual-polarization dual-drive Mach-Zehnder modulator uses the optical signal separated by the main laser as an optical carrier. The upper arm is driven by the reference signal for radar detection and the echo signal to generate an x ​​polarization state signal (a first polarization state signal). The lower arm is driven by the reference signal for frequency measurement and the frequency measurement signal to generate a y polarization state signal (a second polarization state signal) after passing through a 90° polarization rotator, and finally the signals are combined by a polarization beam combiner.

[0085] Step S208: combining the first polarization state signal and the second polarization state signal and performing frequency conversion to obtain an intermediate frequency signal for radar detection and a linear frequency sweep signal for frequency measurement respectively;

[0086] The combined beam signal is input to a microwave photon down-conversion module for down-conversion. The microwave photon down-conversion module includes a polarization beam splitter, a second photodetector, and a third photodetector. The polarization beam splitter is used to separate signals of two orthogonal polarization states. The x polarization state signal (first polarization state signal) is detected by the second photodetector to achieve de-chirping, and the y polarization state signal (second polarization state signal) is detected by the third photodetector to achieve down-conversion and generate an intermediate frequency linear sweep signal.

[0087] Step S209: extracting the position information of the target object in the intermediate frequency signal using an analog-to-digital converter and a digital-to-analog converter;

[0088] The radar detection module includes a low-pass filter, a first analog-to-digital converter and a digital-to-analog converter. The low-pass filter is used to filter out high-frequency harmonics outside the de-chirped signal, and the characteristic value of the target object is extracted through the first analog-to-digital converter and the digital-to-analog converter.

[0089] As the principle Figure 4 As shown in the figure, the echo signal returns from the detection target object and has a delay of Δτ compared with the reference signal. The corresponding de-chirp signal frequency is:

[0090]

[0091] The distance of the target to be measured can be obtained from this frequency: Where c is the speed of light in a vacuum.

[0092] The intermediate frequency linear sweep signal frequency is input into the frequency measurement information processing system, and its frequency is:

[0093]

[0094] Where f m It is the frequency to be measured in the frequency measurement function.

[0095] Step S210: using an electrical bandpass filter and an electrical envelope detector to obtain two output pulses, and the pulse time difference is used to map the frequency to be measured.

[0096] like Figure 5 As shown, if the intermediate frequency linear sweep signal sweeps to the passband of the electric bandpass filter, a pulse will be generated. The envelope detector is used to obtain the envelope of the two pulses:

[0097]

[0098] Where δ(t) represents the envelope of the generated pulse, f filter is the center frequency.

[0099] The time interval between the two pulses is:

[0100] Thus, the frequency-time mapping is completed, the time interval of the pulse is obtained through the second analog-to-digital converter, and then the frequency to be measured is obtained through the second digital-to-analog converter.

[0101] The above analysis is based on the assumption that the reference signal frequency is higher than the frequency of the signal to be measured, so the measurement range is f1-f filter to f2-f filter In fact, if the reference signal frequency is lower than the frequency of the signal to be measured, an intermediate frequency linear sweep signal with an opposite chirp rate will be generated. In this case, frequency-time mapping can still be completed, such as Figure 6 As shown, it provides an additional frequency measurement range f1+f filter to f2+f filter .

[0102] The invention provides a method for radar detection and frequency measurement. Compared with the current technical solution, the invention firstly generates and shares a double-chirp linear frequency sweep signal as a reference light, and uses an integrated dual-polarization dual-drive Mach-Zehnder modulator to simultaneously receive the echo signal and reference signal of the radar detection function and the frequency signal to be measured and the reference signal of the frequency measurement function on two arms, thereby finally realizing an integrated system of frequency measurement and radar detection; secondly, the invention does not use an additional radio frequency source when generating a linear frequency sweep signal, so the generated double-chirp linear frequency sweep signal has the advantages of large frequency sweep bandwidth and flexible adjustability, and can reach a frequency sweep bandwidth exceeding 10=GHz, and the center frequency, bandwidth, frequency band and period of the generated linear frequency sweep signal can be changed by adjusting the injection power, the master-slave laser detuning frequency and the driving voltage, thereby improving the detection accuracy of the radar and the measurement bandwidth of the frequency measurement; finally, the invention does not need an additional optical filter to select the sideband generated after the signal source to be measured modulates the optical carrier, thereby avoiding the influence of other filters on the measurement bandwidth. In addition, the frequency sweep range of the generated double-chirp linear frequency sweep signal can be changed by adjusting the injection parameters, thereby changing the frequency measurement range.

[0103] Please refer to Figure 7 , Figure 7 A structural block diagram of a microwave photon radar detection and frequency measurement device provided in an embodiment of the present invention; the specific device may include:

[0104] The photoelectric conversion module 100 is used to convert the adjustable optical signal into a linear frequency-sweeping electrical signal;

[0105] A first distribution module 200, used to divide the linear frequency sweeping electrical signal into a test signal;

[0106] A second allocation module 300, configured to divide the test signal into a reference signal and a detection signal;

[0107] A radar detection module 400 is used to perform radar detection using the detection signal and obtain an echo signal after being reflected by a target object;

[0108] The frequency measurement module 500 is used to receive a frequency test signal using a frequency receiving device;

[0109] A centralized processing module 600, configured to input the reference signal, the frequency test signal and the echo signal into a dual-polarization dual-drive Mach-Zehnder modulator for processing, and output a first polarization signal and a second polarization signal;

[0110] The radar detection information processing module 700 is used to de-chirp the first polarization state signal to obtain an intermediate frequency signal, extract characteristic information of the target object from the intermediate frequency signal, and obtain position information of the target object;

[0111] The frequency measurement information processing module 800 is used to convert the frequency of the second polarization state signal to obtain a linear frequency sweep signal, calculate multiple pulses of the linear frequency sweep signal, and obtain the frequency to be measured by pulse time difference mapping.

[0112] A radar detection and frequency measurement device in this embodiment is used to implement the aforementioned radar detection and frequency measurement method. Therefore, the specific implementation method of a radar detection and frequency measurement device can be seen in the embodiment part of a radar detection and frequency measurement method in the previous text. For example, the photoelectric conversion module 100, the first allocation module 200, the second allocation module 300, the radar detection module 400, the frequency measurement module 500, the centralized processing module 600, the radar detection information processing module 700 and the frequency measurement information processing module 800 are respectively used to implement steps S101, S102, S103, S104, S105, S106, S107 and S108 in the aforementioned radar detection and frequency measurement method. Therefore, its specific implementation method can refer to the description of the corresponding various parts of the embodiment, which will not be repeated here.

[0113] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0114] Professionals may further appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in the above description according to function. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians may use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present invention.

[0115] The above is a detailed introduction to a radar detection and frequency measurement method and device provided by the present invention. Specific examples are used in this article to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method and core ideas of the present invention. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present invention, the present invention can also be improved and modified, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A microwave photon radar detection and frequency measurement method, characterized in that: include: Converting an adjustable optical signal into a linear frequency-swept electrical signal; Allocating the linear frequency sweeping electrical signal into a test signal and a feedback signal; Allocating the test signal into a reference signal and a probe signal; Using the detection signal to perform radar detection, and obtaining an echo signal after being reflected by a target object; receiving a frequency test signal using a frequency receiving device; Inputting the reference signal, the frequency test signal and the echo signal into a dual-polarization dual-drive Mach-Zehnder modulator for processing, and outputting a first polarization state signal and a second polarization state signal; De-chirping the first polarization state signal to obtain an intermediate frequency signal, extracting characteristic information of the target object from the intermediate frequency signal, and obtaining position information of the target object; The second polarization state signal is frequency-converted to obtain a linear frequency sweep signal, a plurality of pulses of the linear frequency sweep signal are calculated, and the frequency to be measured is obtained by pulse time difference mapping.

2. The method according to claim 1, characterized in that The step of converting the adjustable optical signal into a linear frequency-sweeping electrical signal comprises: generating the adjustable optical signal using a master laser; The adjustable optical signal is input into a slave laser, and the slave laser is used to process and output the linear frequency-sweeping electrical signal.

3. The method according to claim 2, characterized in that The detuning frequency of the master laser and the slave laser is ; in, is the frequency of the optical signal output by the master laser, is the frequency of the optical signal output from the laser.

4. The method according to claim 1, characterized in that The radar detection is performed using the detection signal, and the echo signal is obtained by reflection from the target object, comprising: The detection signal is input into a transmitting antenna and transmitted to free space, and an echo signal reflected by the target object is obtained by using a radar receiving antenna.

5. The method according to claim 1, characterized in that The receiving of the frequency test signal by the frequency receiving device comprises: The signal received by the frequency receiving antenna is input into the amplifier for amplification to obtain a frequency test signal.

6. The method according to claim 1, characterized in that The expression of the reference signal is: ； in, is the amplitude, is an imaginary unit, is the upper limit of the sweep frequency range, is the swept signal bandwidth, For cycle.

7. The method according to claim 1, characterized in that The step of inputting the reference signal, the frequency test signal and the echo signal into a dual-polarization dual-drive Mach-Zehnder modulator for processing and outputting a first polarization signal and a second polarization signal comprises: Inputting the reference signal and the echo signal into the upper arm of the dual-polarization dual-drive Mach-Zehnder modulator, driving the upper arm of the dual-polarization dual-drive Mach-Zehnder modulator, and outputting the first polarization state signal; The reference signal and the frequency test signal are input into the lower arm of the dual-polarization dual-drive Mach-Zehnder modulator to drive the lower arm of the dual-polarization dual-drive Mach-Zehnder modulator and output the second polarization state signal.

8. The method according to claim 1, characterized in that De-chirping the first polarization state signal to obtain an intermediate frequency signal, extracting characteristic information of the target object from the intermediate frequency signal, and obtaining the target object position information comprises: Inputting the first polarization state signal into a polarization beam splitter for frequency conversion, and outputting the intermediate frequency signal; A low-pass filter is used to filter out high-frequency harmonics of the intermediate frequency signal, extract the characteristic value of the target object, and obtain the position information of the target object.

9. The method according to claim 8, characterized in that The step of converting the second polarization state signal to obtain a linear frequency sweep signal, calculating a plurality of pulses of the linear frequency sweep signal, and obtaining a frequency to be measured by pulse time difference mapping comprises: Inputting the second polarization state signal into the polarization beam splitter for frequency conversion, and outputting a linear frequency sweep signal; Inputting the linear frequency sweep signal into a bandpass filter for processing, and outputting a plurality of pulse values; The frequency of the target object is obtained according to the time difference mapping of the multiple pulse values.

10. A device for microwave photon radar detection and frequency measurement using the method of any one of claims 1 to 9, characterized in that: include: A photoelectric conversion module, used for converting an adjustable optical signal into a linear frequency-sweeping electrical signal; A first distribution module, used for dividing the linear frequency sweeping electrical signal into a test signal; A second allocation module, used for dividing the test signal into a reference signal and a detection signal; A radar detection module, used to perform radar detection using the detection signal and obtain an echo signal after being reflected by a target object; A frequency measurement module, used for receiving a frequency test signal using a frequency receiving device; A centralized processing module, used for inputting the reference signal, the frequency test signal and the echo signal into a dual-polarization dual-drive Mach-Zehnder modulator for processing, and outputting a first polarization signal and a second polarization signal; A radar detection information processing module, configured to de-chirp the first polarization state signal to obtain an intermediate frequency signal, extract characteristic information of the target object from the intermediate frequency signal, and obtain position information of the target object; The frequency measurement information processing module is used to convert the frequency of the second polarization state signal to obtain a linear frequency sweep signal, calculate multiple pulses of the linear frequency sweep signal, and obtain the frequency to be measured by pulse time difference mapping.

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