On-chip integrated millimeter-wave optical common aperture detection system

Abstract

The present invention provides an on-chip integrated millimeter-wave optical common-aperture detection system, relating to the field of radar optical composite detection technology. The system comprises a common-aperture array antenna and radio frequency front-end, an optoelectronic hybrid module, a laser array, a multi-wavelength laser, a first analog-to-digital converter, a second analog-to-digital converter, a first digital signal processor, a second digital signal processor, and a control terminal. The system utilizes an optoelectronic hybrid integrated design, effectively integrating the optical imaging system and the millimeter-wave array. These systems can mutually provide target information for precise tracking and imaging, meeting the needs of optical and microwave collaborative detection in space-based, unmanned aerial vehicle (UAV) and other small platform-borne detection applications.

Description

Technical Field

[0001] The present invention relates to the technical field of radar optical composite detection, and in particular to an on-chip integrated millimeter-wave optical common aperture detection system. Background Art

[0002] The electromagnetic environment is becoming increasingly complex, and radar optical composite detection systems are widely used in various fields due to their strong anti-interference ability and high environmental adaptability.

[0003] For example, in the field of space exploration, continuous tracking and identification of space targets is typically achieved by coordinating ground-based optical systems with radar systems (i.e., radar-optical system collaboration). Another commonly used radar-optical composite detection system is the Cassegrain composite structure, which improves on the Cassegrain optical imaging system to enable it to receive and transmit microwave radar signals.

[0004] However, the above-mentioned radar optical system collaboration and Cassegrain composite structure designs have low integration and occupy a large space, which is not conducive to their widespread application in small platforms such as low-orbit satellites and drones. Summary of the Invention

[0005] (1) Technical problems solved

[0006] In view of the shortcomings of the existing technology, the present invention provides an on-chip integrated millimeter-wave optical common aperture detection system, which solves the technical problem of different integration levels of existing radar optical composite detection systems.

[0007] (2) Technical solution

[0008] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0009] The present invention provides an on-chip integrated millimeter-wave optical common-aperture detection system, comprising a common-aperture array antenna and a radio frequency front end, an optoelectronic hybrid module, a laser array, a multi-wavelength laser, a first analog-to-digital converter, a second analog-to-digital converter, a first digital signal processor, a second digital signal processor, and a control terminal;

[0010] The common aperture array antenna comprises a millimeter wave antenna array and a lens imaging array, and the lens imaging array is embedded in the millimeter wave array;

[0011] The radio frequency front end is connected to the millimeter wave antenna array and is used to switch the transmission and reception of the millimeter wave antenna array;

[0012] The optoelectronic hybrid module includes an optical processing unit, a radar transmitting unit, and a radar receiving unit. The optical processing unit is connected to the lens imaging array and is used to process the optical signal received by the lens imaging array to form an optical analog signal. The radar transmitting unit and the radar receiving unit are both connected to the radio frequency front end and are used to receive and send radio frequency signals.

[0013] The laser array provides an optical carrier for the radar receiving unit; the multi-wavelength laser provides an optical carrier for the radar transmitting unit;

[0014] The first analog-to-digital converter discretely processes the optical analog signal output by the optical processing unit to obtain an optical digital signal; the second analog-to-digital converter discretely processes the radio frequency analog signal output by the radar receiving unit to obtain a microwave digital signal; the first analog-to-digital converter and the second analog-to-digital converter exchange information;

[0015] The first digital signal processor processes the optical digital signal to achieve precise imaging; the second digital signal processor processes the microwave digital signal to achieve target tracking;

[0016] The control terminal receives and analyzes the output results of the first digital signal processor and the second digital signal processor, and controls the radar transmitting unit and the radar receiving unit according to the analysis results to achieve waveform and beam control.

[0017] Preferably, the lens imaging array is embedded in the millimeter wave array in an umbrella-rib radial shape.

[0018] Preferably, the optical processing unit includes an optical coupling array, an optical baseline interference network and an orthogonal balanced photodetector array; wherein the optical coupling array includes multiple groups of vertical grating couplers for collecting light information at different positions under the lens, and transmitting the collected light information to the optical baseline interference network for processing, and the output of the optical baseline interference network is converted into photoelectricity through the orthogonal balanced photodetector array to output a radio frequency signal.

[0019] Preferably, the optical baseline interferometry network includes multiple groups of coherent processing components;

[0020] Each set of coherent processing components includes two phase shifters, one coupler and two arrayed waveguide gratings;

[0021] The phase shifter is used to adjust the phases of the two optical paths to meet the coherence condition; the coupler couples the two optical paths to generate two groups of coherent light; and the two arrayed waveguide gratings divide the two groups of related light into multiple wavelengths to obtain narrow spectrum bands that are easy to interfere and process.

[0022] Preferably, the radar transmitting unit includes a waveform generating module, a carrier module, a first optical beam forming network and a photoelectric conversion array; wherein the waveform generating module generates a radio frequency signal according to the radio frequency signal output by the second analog-to-digital converter and the control signal of the control terminal, and the radio frequency signal and the optical carrier generated by the multi-wavelength laser are input into the carrier module for modulation to form a laser waveform; the laser waveform and the signal of the control terminal are input into the first optical beam forming network, and the first optical beam forming network outputs a transmitting optical beam; the transmitting optical beam passes through the photoelectric conversion array to form a radio frequency output signal, and the radio frequency output signal passes through the radio frequency front end and is transmitted by the millimeter wave antenna array.

[0023] Preferably, the photoelectric conversion array includes multiple groups of vertical grating couplers, multiple groups of Mach-Zehnder modulators and multiple groups of photodetectors; the Mach-Zehnder modulator includes multiple input ports, specifically: port 1, port 3 and port 5;

[0024] Among them, the laser emitted by the first optical beamforming network is processed by the vertical grating coupler and input into the Mach-Zehnder modulator through port 1. The radar echo input local oscillator RF signal is input into the Mach-Zehnder modulator through port 3. Port 5 is used to input the RF clock signal. An optical comb is generated in the phase modulator in the 5-port branch of the Mach-Zehnder modulator; the output of the Mach-Zehnder modulator is beat-frequencyed by a photodetector.

[0025] Preferably, the radar receiving unit includes an electro-optical conversion array, a second optical beamforming network, and an optical channelization network; wherein the electro-optical conversion array loads the echo signal received by the millimeter wave antenna array onto the optical carrier generated by the laser array to form a received optical waveform, and the received optical waveform and the signal of the control terminal are jointly input into the second optical beamforming network, and the output optical signal is processed by the optical channelization network to output a radio frequency signal.

[0026] Preferably, the electro-optical conversion array includes multiple groups of vertical grating couplers and Mach-Zehnder modulators; the Mach-Zehnder modulator includes multiple input ports, specifically: a first input port, a second input port and a third input port;

[0027] The laser emitted by the laser array is coupled to the chip through a vertical grating coupler, and the output of the vertical grating coupler is input into the Mach-Zehnder modulator through the second input port. The Mach-Zehnder modulator loads the radio frequency signal onto the laser carrier. The first input port of the Mach-Zehnder modulator is used to input the radar echo radio frequency signal output by the radio frequency front end, and the third input port is used to input the radio frequency clock signal; the Mach-Zehnder modulator outputs a received light waveform.

[0028] Preferably, the optical channelized network comprises a semiconductor optical amplifier, an optical filter, an optical circulator, an optical splitter, a defective BRAGG grating waveguide, a microwave photon frequency converter and a photodetector connected in sequence;

[0029] Among them, the semiconductor optical amplifier is used to amplify the optical carrier to ensure the intensity of the subsequent splitting light; the optical filter is used to filter out noise in non-working frequency bands; the optical circulator is used to remove reflected light in the optical path; the optical splitter is used for channel splitting; the defect BRAGG grating waveguide selects the channel frequency point of the working frequency band through the notch characteristics generated by the defect layer in the periodic structure, and continuous frequency notches can be obtained by adjusting the defect layer parameters; the microwave photon frequency conversion is used for secondary down-conversion processing; and the photodetector is used for beat frequency and photoelectric conversion.

[0030] Preferably, a frequency source is further included, and the frequency source provides clock information for a chip with a clock port in the on-chip integrated millimeter-wave optical common aperture detection system.

[0031] (3) Beneficial effects

[0032] The present invention provides an on-chip integrated millimeter-wave optical common-aperture detection system. Compared with the existing technology, it has the following advantages:

[0033] The present invention has completed an on-chip integrated millimeter-wave optical common-aperture detection system, which adopts an optoelectronic hybrid integration design and effectively compatible with the optical imaging system and the millimeter-wave array. They can provide each other with target information to achieve precise tracking and accurate imaging, and meet the needs of optical and microwave collaborative detection in the field of small platform-based detection such as space-based and unmanned aerial vehicles. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. 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 any creative work.

[0035] Figure 1 Schematic diagram of the structure of the on-chip integrated millimeter-wave optical common aperture detection system;

[0036] Figure 2 Schematic diagram of the RF front end;

[0037] Figure 3 Schematic diagram of the photoelectric conversion array;

[0038] Figure 4 Schematic diagram of electro-optical conversion array;

[0039] Figure 5Schematic diagram of optical beamforming network;

[0040] Figure 6 This is a schematic diagram of an optical channelized network;

[0041] Figure 7 This is a schematic diagram of the carrier module;

[0042] Figure 8 Schematic diagram of optical coupling array;

[0043] Figure 9 Schematic diagram of the optical baseline interferometry network. DETAILED DESCRIPTION

[0044] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention are clearly and completely described. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0045] The embodiments of the present application solve the technical problem of different integration levels of existing radar optical composite detection systems by providing an on-chip integrated millimeter-wave optical common-aperture detection system, and realize an on-chip integrated millimeter-wave optical common-aperture design with high integration and light weight, which can be widely used in small platforms such as low-orbit satellites and drones.

[0046] The technical solution in the embodiments of the present application is to solve the above technical problems, and the overall idea is as follows:

[0047] The existing radar-optical composite detection system has the problems of low integration, large space occupation, and inconsistent time and space references, which is not conducive to its widespread application in small platforms such as low-orbit satellites and drones.

[0048] To address these issues, embodiments of the present invention propose an on-chip integrated millimeter-wave optical common-aperture detection system. This system uses multi-baseline interferometry to acquire the target's spatial frequency information, obtaining a target image for search. It also simultaneously transmits and receives millimeter waves and controls phase differences, directing the main beam toward the target for tracking. This on-chip integrated millimeter-wave optical common-aperture design offers the advantages of efficient aperture utilization, light weight, and compact structure, providing a new approach to the integrated design of radar optical composite detection systems.

[0049] In order to better understand the above technical solution, the above technical solution will be described in detail below with reference to the accompanying drawings and specific implementation methods.

[0050] The present invention provides an on-chip integrated millimeter wave optical common aperture detection system, such as Figure 1As shown, it includes a common aperture array antenna and a radio frequency front end, an optoelectronic hybrid module, a laser array, a multi-wavelength laser, a first analog-to-digital converter, a second analog-to-digital converter, a first digital signal processor, a second digital signal processor and a control terminal;

[0051] The common aperture array antenna includes a millimeter wave antenna array and a lens imaging array, and the lens imaging array is embedded in the millimeter wave array;

[0052] The radio frequency front end is connected to the millimeter wave antenna array and is used to switch the transmission and reception of the millimeter wave antenna array;

[0053] The optoelectronic hybrid module includes an optical processing unit, a radar transmitting unit and a radar receiving unit. The optical processing unit is connected to the lens imaging array and is used to process the optical signal received by the lens imaging array to form an optical analog signal. The radar transmitting unit and the radar receiving unit are both connected to the RF front end and are used to receive and send RF signals.

[0054] The laser array provides optical carrier for the radar receiving unit; the multi-wavelength laser provides optical carrier for the radar transmitting unit;

[0055] The first analog-to-digital converter discretely processes the optical analog signal output by the optical processing unit to obtain an optical digital signal; the second analog-to-digital converter discretely processes the radio frequency analog signal output by the radar receiving unit to obtain a microwave digital signal; the first analog-to-digital converter and the second analog-to-digital converter exchange information;

[0056] The first digital signal processor extracts the amplitude / phase information of the complex coherence factor of the optical digital signal, performs filtering, and performs dirty image restoration processing to achieve precise imaging. The second digital signal processor performs pulse compression, clutter filtering, Doppler processing, moving target detection, and real-time target tracking on the microwave digital signal.

[0057] The control terminal receives and analyzes the output results of the first digital signal processor and the second digital signal processor, and controls the radar transmitting unit and the radar receiving unit according to the analysis results to achieve waveform and beam control.

[0058] The embodiment of the present invention has completed an on-chip integrated millimeter-wave optical common-aperture detection system, which adopts an optoelectronic hybrid integration design and effectively compatible with the optical imaging system and the millimeter-wave array. The two systems can provide target information to each other to achieve precise tracking and accurate imaging, and meet the needs of optical and microwave collaborative detection in the field of small platform-based detection such as space-based and unmanned aerial vehicles.

[0059] Example 1:

[0060] like Figure 1As shown, the common-aperture array antenna includes a lens imaging array and a millimeter-wave antenna array. The lens imaging array is in an umbrella-rib-radiating shape and is embedded in the millimeter-wave array. The light radiated by the target passes through the lens imaging array and the optical coupling array into the on-chip integrated system for imaging processing. The millimeter-wave antenna array adopts an integrated transceiver design, and the transceiver switching is performed through the RF front end. The millimeter waves emitted by the radar illuminate the target to form an echo, which is received by the array and processed by the on-chip integrated system to obtain the target's position information.

[0061] The RF front end, optoelectronic hybrid module, laser array, multi-wavelength laser, first analog-to-digital converter, second analog-to-digital converter, first digital signal processor, second digital signal processor, and control terminal are integrated on a single PCB. Components in the circuit can be replaced with devices having equivalent functions.

[0062] The optoelectronic hybrid module includes an optical processing unit, a radar transmitting unit and a radar receiving unit.

[0063] The optical processing unit includes an optical coupling array, an optical baseline interferometer network, and an orthogonal balanced photodetector array. The optical coupling array includes multiple sets of vertical grating couplers, which collect light information from different positions under the lens and transmit the collected light information to the optical baseline interferometer network for processing. The output of the optical baseline interferometer network is converted to photoelectricity by the orthogonal balanced photodetector array and outputs a radio frequency signal.

[0064] The radar transmitting unit includes a waveform generation module, a carrier module, a first optical beamforming network, and an optoelectronic conversion array. The waveform generation module generates an RF signal based on the RF signal output by the second analog-to-digital converter and the control signal from the control terminal. This RF signal and the optical carrier generated by the multi-wavelength laser are input into the carrier module for modulation to form a laser waveform. The laser waveform and the signal from the control terminal are input into the first optical beamforming network, which outputs a transmit optical beam. The transmit optical beam passes through the optoelectronic conversion array to form an RF output signal, which is transmitted by the millimeter-wave antenna array via the RF front end.

[0065] The radar receiving unit includes an electro-optical conversion array, a second optical beamforming network, and an optical channelization network. The electro-optical conversion array loads the echo signal received by the millimeter-wave antenna array onto the optical carrier generated by the laser array, forming a received optical waveform. The received optical waveform and the signal from the control terminal are input into the second optical beamforming network. The output optical signal is processed by the optical channelization network and output as a radio frequency signal.

[0066] The optoelectronic hybrid module is concentrated on a silicon substrate through optoelectronic large-scale hybrid integration, and can also be individually packaged as an independent chip module.

[0067] The first analog-to-digital converter (ADC1) and the second analog-to-digital converter (ADC2) perform discrete processing on the analog signal output by the chip to obtain a digital signal. The first digital signal processor (DSP1) and the second digital signal processor (DSP2) perform pulse compression, clutter filtering, Doppler processing, and moving target detection on the microwave digital signal. They also perform amplitude / phase information extraction, filtering, and dirty image restoration on the optical digital signal. After completing signal analysis, the control terminal displays information and provides control signals to the on-chip integrated system to implement waveform and beam control.

[0068] The on-chip integrated millimeter-wave optical common-aperture detection system further includes a frequency source, which provides clock information for multiple chips in the system.

[0069] Example 2:

[0070] With reference to Example 1, the design of the eight important components in Example 1 is described in detail. The following detailed description is merely a specific description of the feasible implementation of Example 1 in this application and is not intended to limit the scope of protection of Example 1. All equivalent implementations that do not deviate from the system architecture of Example 1 are included in the scope of protection of this application. The components in this circuit can be replaced with components with the same function.

[0071] See Figure 2 The RF front end includes a 1:4 power splitter, an RF switch, a transmit branch (upper branch), and a receive branch (lower branch). The 1:4 power splitter can divide a large-scale array into a combination of multiple 2×2 sub-arrays, and the RF switch can switch the antenna operating state to the transmit branch or the receive branch.

[0072] The transmitting branch includes a power amplifier (PA), a programmable gain amplifier (PGA), and a phase shifter (PS). The PA amplifies the transmitted RF signal. The receiving branch includes a low-noise amplifier (LNA), a PGA, and a PS. The LNA amplifies the received RF signal. The PGA and PS respectively precisely control the RF signal's phase and gain.

[0073] See Figure 3The photoelectric conversion array consists of multiple groups of vertical grating couplers (VGC), Mach-Zehnder modulators (MZM) and photodetectors (PD). The laser emitted by the optical beam forming network passes through the vertical grating coupler and then enters the MZM through port 1. Port 3 is the port for the radar echo to input the local oscillator RF signal, and port 5 is the port for the frequency source to input the RF clock signal, so as to generate an optical comb in the phase modulator in the 5-port branch of the MZM. The frequency source is divided into two paths, both with a frequency of f ck , one of the channels is frequency-multiplied, i.e. the frequency is 2f ck Finally, the two paths are combined into one path through a coupler. The RF clock signal contains f ck and 2f ck Two frequency components contribute to the generation of higher-order harmonics in the MZM, including f ck 、2f ck 、3f ck 、4f ck Then, the optical component generated by the radar RF signal and the high-order harmonics beat the frequency in the PD to achieve up-conversion of the RF signal to a multiple of the clock frequency, i.e., f RF =nf ck ±f IF The up-converted signal enters the RF front end through port 4.

[0074] See Figure 4 The electro-optical conversion array consists of multiple sets of VGCs and MZMs. The laser light emitted by the laser array is coupled to the chip through port 2 through the VGC. The RF signal is loaded onto the laser carrier through the Mach-Zehnder modulator. Port 1 is the port where the RF front end outputs the radar echo RF signal, and port 3 is the port where the frequency source inputs the RF clock signal. Similar to the above, down-conversion of the original fIF can be achieved so that the signal can enter the back-end for processing.

[0075] See Figure 5 The optical beamforming network includes multiple sets of timing controls, optical delays, optical switches, variable optical attenuators (VOAs), and wavelength division multiplexing (WDMs). The timing controls use electro-optical and thermo-optical effects to control the optical switches to switch the optical paths. The optical delays are used to obtain delay combinations. The VOAs can control the optical amplitude of each branch, and the WDMs can multiplex optical wavelength components.

[0076] See Figure 6The optical channelized network includes a semiconductor optical amplifier (SOA), an optical filter (OF), an optical circulator (OC), an optical branching device (OBD), a defective Bragg grating waveguide (DBG), microwave photon frequency conversion, and a PD. The SOA is used for optical carrier amplification to ensure the intensity of the subsequent split light; the OF is used for noise filtering in non-working frequency bands; the OC can be used to remove reflected light in the optical path; the OBD is used for channel splitting; the DBG selects the channel frequency point of the working frequency band through the notch characteristics generated by the defect layer in the periodic structure, and continuous frequency notches can be obtained by adjusting the defect layer parameters; the microwave photon frequency conversion can be used for secondary down-conversion processing, and its working principle refers to Figure 3 The PD is used for beat frequency and photoelectric conversion.

[0077] See Figure 7 The carrier module includes VGC and MZM. The laser emitted by the multi-wavelength laser is coupled to the chip through VGC, and the waveform generation module can modulate the laser waveform through the MZM.

[0078] See Figure 8 The optical coupling array consists of multiple sets of VGCs, placed behind the lenses within the common-aperture array antenna, to collect light information from different locations beneath the lenses. The VGCs at the same location beneath the two sets of lenses are connected to a coherent processing component within the optical baseline interferometer network.

[0079] See Figure 9 The optical baseline interference network is composed of multiple groups of coherent processing components, one of which includes two phase shifters (PS), one coupler, and two arrayed waveguide gratings (AWG). The PS is used to adjust the phase of the two optical paths so that they meet the coherence condition; the coupler couples the two optical paths to produce two groups of coherent light; the AWG divides the two groups of related light into multiple wavelengths to obtain a narrow spectrum that is easy to interfere and process. Two different groups of lenses can be combined to form multiple groups of baselines. The spatial frequency information of the target can be obtained through multi-baseline combined interference processing, and the phase and amplitude information of each path can be obtained for imaging processing.

[0080] In summary, compared with the existing technology, the present invention has the following beneficial effects:

[0081] The embodiment of the present invention has completed an on-chip integrated millimeter-wave optical common-aperture detection system, which adopts an optoelectronic hybrid integration design and effectively compatible with the optical imaging system and the millimeter-wave array. The two systems can provide target information to each other to achieve precise tracking and accurate imaging, and meet the needs of optical and microwave collaborative detection in the field of small platform-based detection such as space-based and unmanned aerial vehicles.

[0082] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply the existence of any such actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or device comprising the element.

[0083] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. An on-chip integrated millimeter-wave optical common aperture detection system, characterized in that: It includes a common aperture array antenna and a radio frequency front end, an optoelectronic hybrid module, a laser array, a multi-wavelength laser, a first analog-to-digital converter, a second analog-to-digital converter, a first digital signal processor, a second digital signal processor, and a control terminal; The common aperture array antenna comprises a millimeter wave antenna array and a lens imaging array, and the lens imaging array is embedded in the millimeter wave array; The radio frequency front end is connected to the millimeter wave antenna array and is used to switch the transmission and reception of the millimeter wave antenna array; The optoelectronic hybrid module includes an optical processing unit, a radar transmitting unit, and a radar receiving unit. The optical processing unit is connected to the lens imaging array and is used to process the optical signal received by the lens imaging array to form an optical analog signal. The radar transmitting unit and the radar receiving unit are both connected to the radio frequency front end and are used to receive and send radio frequency signals. The laser array provides an optical carrier for the radar receiving unit; the multi-wavelength laser provides an optical carrier for the radar transmitting unit; The first analog-to-digital converter discretely processes the optical analog signal output by the optical processing unit to obtain an optical digital signal; the second analog-to-digital converter discretely processes the radio frequency analog signal output by the radar receiving unit to obtain a microwave digital signal; the first analog-to-digital converter and the second analog-to-digital converter exchange information; The first digital signal processor processes the optical digital signal to achieve precise imaging; the second digital signal processor processes the microwave digital signal to achieve target tracking; The control terminal receives and analyzes the output results of the first digital signal processor and the second digital signal processor, and controls the radar transmitting unit and the radar receiving unit according to the analysis results to achieve waveform and beam control.

2. The on-chip integrated millimeter-wave optical common-aperture detection system according to claim 1, wherein: The lens imaging array is embedded in the millimeter wave array in an umbrella-rib radial shape.

3. The on-chip integrated millimeter-wave optical common-aperture detection system according to claim 1, wherein: The optical processing unit includes an optical coupling array, an optical baseline interference network and an orthogonal balanced photodetector array; wherein the optical coupling array includes multiple groups of vertical grating couplers, which are used to collect light information at different positions under the lens and transmit the collected light information to the optical baseline interference network for processing. The output of the optical baseline interference network is converted into photoelectricity by the orthogonal balanced photodetector array to output a radio frequency signal.

4. The on-chip integrated millimeter-wave optical common-aperture detection system according to claim 3, wherein: The optical baseline interferometry network includes multiple groups of coherent processing components; Each set of coherent processing components includes two phase shifters, one coupler and two arrayed waveguide gratings; The phase shifter is used to adjust the phases of the two optical paths to meet the coherence condition; the coupler couples the two optical paths to generate two groups of coherent light; and the two arrayed waveguide gratings divide the two groups of related light into multiple wavelengths to obtain narrow spectrum bands that are easy to interfere and process.

5. The on-chip integrated millimeter-wave optical common-aperture detection system according to claim 1, wherein: The radar transmitting unit includes a waveform generation module, a carrier module, a first optical beamforming network, and a photoelectric conversion array. The waveform generation module generates a radio frequency signal based on the radio frequency signal output by the second analog-to-digital converter and the control signal of the control terminal. The radio frequency signal and the optical carrier generated by the multi-wavelength laser are input into the carrier module for modulation to form a laser waveform. The laser waveform and the signal of the control terminal are input into the first optical beamforming network, which outputs a transmission optical beam. The transmission optical beam passes through the photoelectric conversion array to form a radio frequency output signal. The radio frequency output signal passes through the radio frequency front end and is transmitted by the millimeter wave antenna array.

6. The on-chip integrated millimeter-wave optical common-aperture detection system according to claim 5, characterized in that: The photoelectric conversion array includes multiple groups of vertical grating couplers, multiple groups of Mach-Zehnder modulators and multiple groups of photodetectors; the Mach-Zehnder modulator includes multiple input ports, specifically: port 1, port 3 and port 5; Among them, the laser emitted by the first optical beamforming network is processed by the vertical grating coupler and input into the Mach-Zehnder modulator through port 1. The radar echo input local oscillator RF signal is input into the Mach-Zehnder modulator through port 3. Port 5 is used to input the RF clock signal. An optical comb is generated in the phase modulator in the 5-port branch of the Mach-Zehnder modulator; the output of the Mach-Zehnder modulator is beat-frequencyed by a photodetector.

7. The on-chip integrated millimeter-wave optical common-aperture detection system according to claim 1, wherein: The radar receiving unit includes an electro-optical conversion array, a second optical beamforming network, and an optical channelization network. The electro-optical conversion array loads the echo signal received by the millimeter-wave antenna array onto the optical carrier generated by the laser array to form a received optical waveform. The received optical waveform and the signal from the control terminal are jointly input into the second optical beamforming network. The output optical signal is processed by the optical channelization network and output as a radio frequency signal.

8. The on-chip integrated millimeter-wave optical common-aperture detection system according to claim 7, wherein: The electro-optical conversion array includes multiple groups of vertical grating couplers and Mach-Zehnder modulators; the Mach-Zehnder modulator includes multiple input ports, specifically: a first input port, a second input port and a third input port; The laser emitted by the laser array is coupled to the chip through a vertical grating coupler, and the output of the vertical grating coupler is input into the Mach-Zehnder modulator through the second input port. The Mach-Zehnder modulator loads the radio frequency signal onto the laser carrier. The first input port of the Mach-Zehnder modulator is used to input the radar echo radio frequency signal output by the radio frequency front end, and the third input port is used to input the radio frequency clock signal; the Mach-Zehnder modulator outputs a received light waveform.

9. The on-chip integrated millimeter-wave optical common-aperture detection system according to claim 7, wherein: The optical channelized network includes a semiconductor optical amplifier, an optical filter, an optical circulator, an optical splitter, a defect BRAGG grating waveguide, a microwave photon frequency converter and a photodetector connected in sequence; Among them, the semiconductor optical amplifier is used to amplify the optical carrier to ensure the intensity of the subsequent splitting light; the optical filter is used to filter out noise in non-working frequency bands; the optical circulator is used to remove reflected light in the optical path; the optical splitter is used for channel splitting; the defect BRAGG grating waveguide selects the channel frequency point of the working frequency band through the notch characteristics generated by the defect layer in the periodic structure, and continuous frequency notches can be obtained by adjusting the defect layer parameters; the microwave photon frequency conversion is used for secondary down-conversion processing; and the photodetector is used for beat frequency and photoelectric conversion.

10. The on-chip integrated millimeter-wave optical common aperture detection system according to any one of claims 1 to 9, characterized in that: The system also includes a frequency source, which provides clock information for a chip with a clock port in an on-chip integrated millimeter-wave optical common aperture detection system.

Images