CN108919201B - Multifunctional radar all-optical receiving processing system and processing method - Google Patents

Abstract

A multifunctional radar all-optical receiving and processing system and processing method. Its structure includes: a multi-channel optical signal module, a pulse light source, a first wavelength division multiplexing module, a photon sampling gate, a second wavelength division multiplexing module, a PD array, and an EDAC array. The method is based on the photon parameter sampling technology, only one photon sampling gate is used to realize the sampling of the radar receiving signals of multiple channels at the same time, and then the back-end parallel data processing is performed, thereby greatly simplifying the architecture of the multi-functional radar receiving system. The method can be widely used in receivers of multi-band radars, MIMO radars and phased array radars and other multi-function radars.

Description

Multifunctional radar all-optical receiving and processing system and processing method

technical field

The invention relates to the field of microwave photonic signal processing, in particular to a multifunctional radar all-optical receiving system and a processing method.

Background technique

With the continuous development of modern electronic information technology, multi-functional integrated integration has become the development trend of future electronic information systems. In the radar system, it is possible to integrate various functions such as electronic countermeasures, target search, target imaging, and communication to become the development direction of future radar systems. Hence the need for multi-band, reconfigurable radar systems. Among them, the multi-band reconfigurable multi-function radar receiver is an important part of realizing the above-mentioned radar system.

In order to realize the signal reception of multiple functions and cover the frequency range of multiple bands, the radar receiver needs to be comprehensively designed. The most direct solution is a combined receiver: use multiple receivers in parallel, or multiple devices in parallel, each receiver covers a single frequency band, or each device performs a single function. This is also the most commonly used method at present. At the same time, since the commonly used radar receivers are superheterodyne receivers, many components must use separate components, so the integration level is very low, resulting in a large volume and low resource utilization. . With the rapid development of modern integrated circuit technology, a variety of fully integrated single-chip receivers have appeared, including zero-IF receivers and low-IF receivers, all of which have the advantages of simple structure, small size, full integration, and frequency coverage. Wide, high output bandwidth advantages. However, the above receiver still needs to perform analog down-conversion processing on the received signals of different frequency bands. This increases the complexity of the analog front end and limits its application in multi-function radar receivers.

With the development of microwave photonics technology, it has a wide range of applications in the field of radar signal reception. On the one hand, photonic analog-to-digital conversion technology has the advantages of low time jitter and large bandwidth, and can directly perform high-performance broadband direct processing of multi-band RF signals. Sampling [J. Kim, et al., "Photonic subsampling analog-to-digital conversion of microwave signals at 40-GHz with higher than 7-ENOB resolution," Optics Express, vol.16, no.21, pp.16509-16515, 2008.], thereby realizing multi-function radar signal reception in the all-digital domain. On the other hand, real-time delay line technology based on photons effectively overcomes the limitation of aperture transit time in traditional phased array antennas [K. Garenaux, et al., "Recent breakthroughs in RFphotonics for radar systems," Aerospace and Electronic Systems Magazine , IEEE, vol.22, pp.3-8, 2007.]. However, the research on the multi-function radar receiving system based on microwave photonic technology is still in the preliminary stage, and the reconfiguration of the system is not high, and multiple receiver systems are still needed for the simultaneous reception of radar signals in multiple bands, which limits the microwave photonics. Application of technology in multi-function radar receiving system.

SUMMARY OF THE INVENTION

The purpose of the present invention is to propose a multifunctional radar all-optical receiving system and processing method aiming at the deficiencies of the prior art. The method is based on the photon parameter sampling technology, only one photon sampling gate is used to realize the sampling of the radar receiving signals of multiple channels at the same time, and then the back-end parallel data processing is performed, thereby greatly simplifying the architecture of the multi-functional radar receiving system. This method can be widely used in receivers of multi-band radars, MIMO radars and phased array radars and other multi-function radars.

The technical solution of the present invention is as follows:

A multifunctional radar all-optical receiving and processing system, which is characterized in that it includes: a multi-channel optical signal module, a pulsed light source, a first wavelength division multiplexing module, a photon sampling gate, a second wavelength division multiplexing module, a PD array, and an EADC. Array, the specific connection relationship is as follows:

When the system is used as the receiver of the phased array radar, the multi-channel optical signal module includes N radar signal receiving channels, which are composed of N continuous light sources with different wavelengths, N receiving antennas, N electro-optical modulators, and N channels. The first output end of the N continuous light sources with different wavelengths is connected with the first input end of the electro-optical modulator, and the first output ends of the N receiving antennas are connected with the first output end of the N receiving antennas. The second input end of the N-way electro-optical modulator is connected, the first output end of the N-way electro-optical modulator is connected to the first input end of the N-way adjustable delay unit, and the N-way electro-optical modulator is connected to the first input end of the N-way adjustable delay unit. The first output end of the adjustable delay unit is used as the N-way optical signal output end of the multi-channel optical signal module, and the N-way optical signal output ends of the multi-channel optical signal module are respectively multiplexed with the first wavelength division multiplexing. The N input terminals of the module are connected, the first output terminal of the first wavelength division multiplexing module is connected to the first input terminal of the photon sampling gate, and the first output terminal of the pulsed light source is connected to the first input terminal of the photon sampling gate. The second input end of the photon sampling gate is connected, the first output end of the photon sampling gate is connected with the first input end of the second wavelength division multiplexing module, and the second wavelength division multiplexing module The output end of the PD array is directly connected to the first input end of the single PD unit of the PD array, and the first output end of the single PD unit performs data processing with the PD array;

When the system is used as a receiver for multi-band radar, MIMO or other radars, the multi-channel optical signal module includes N radar signal receiving channels, which are composed of N continuous light sources with different wavelengths, N receiving antennas and N electro-optic modulations. The first output end of the N channels of continuous light sources with different wavelengths is connected to the first input end of the electro-optic modulator, and the first output ends of the N receiving antennas are connected to the N channels The second input end of the electro-optical modulator is connected, the first output end of the N-channel electro-optical modulator is used as the N-channel optical signal output end of the multi-channel optical signal module, the N-channel optical signal module of the multi-channel optical signal module is connected. The output ends of the optical signals are respectively connected with the N input ends of the first wavelength division multiplexing module, and the first output end of the first wavelength division multiplexing module is connected with the first input end of the photon sampling gate, The first output terminal of the pulsed light source is connected to the second input terminal of the photon sampling gate, and the first output terminal of the photon sampling gate is connected to the first input terminal of the second wavelength division multiplexing module. The N output ends of the second wavelength division multiplexing are respectively connected to the first input ends of the N PD units of the PD array, and the first output ends of the N PD units are connected to the first input ends of the N PD units. The first input ends of the N EADC units of the EADC array are connected to perform parallel processing of signals.

The multi-function radar all-optical receiving and processing method using the above-mentioned multi-function radar all-optical receiving and processing system is characterized in that the method comprises the following steps:

_①N continuous optical carriers with different wavelengths (λ ₁ , λ ₂ , ... , and the sampling pulse light (λ _sampling ) acts in the photonic nonlinear medium, and all-optical sampling is realized in the photon sampling gate; The signal can be directly used as N-channel optical domain signal, and is multiplexed into one signal by the first wavelength division multiplexing module, and then performs all-optical sampling with the sampling pulse light in the photon sampling gate;

2. After the photon sampling gate is sampled, the idle frequency optical signals (λi ₁ , λi ₂ , ... λi _N ) of the N channels corresponding to the N channels of the received optical signals are simultaneously generated, that is, the simultaneous sampling of the N channels of received signals is realized; Then, through the second wavelength division multiplexing module, the idle frequency optical signals (λi ₁ , λi ₂ , ... λi _N ) produced after sampling are divided into N paths respectively passing through the N PD arrays and the N EADC arrays. The signal processing of each EADC unit completes the simultaneous parallel reception of the multi-function radar;

③ For phased array radar reception, this method is also applicable: N-path optical domain signals are first subjected to delay adjustment by the N-path adjustable delay unit, and then all-optical sampling is performed through the photon sampling gate, and all Optical sampling generates _N channels of idler optical signals ₍ λi ₁ , _{λi 2 ,} ... ... λi _N ) is simultaneously filtered into one signal, and then the receiving beam scanning of the phased array can be realized through signal processing of the single PD array and the single EADC unit of the EADC array.

Based on the above technical characteristics, the present invention has the following advantages:

1. Based on all-optical sampling technology, the signals received by multiple radars can be sampled at the same time, thus greatly simplifying the radar receiving system.

2. The method can be widely used in phased array radar, MIMO radar, multi-band radar and other multi-functional radar systems, and can realize the modular and reconfigurable development of multi-functional radar receiving systems.

Description of drawings

FIG. 1 is a schematic structural diagram of a multi-function radar all-optical receiving and processing system according to the present invention.

FIG. 2 is a schematic diagram of two structures of a multi-channel optical signal module.

Figure 3 is a schematic diagram of the spectrum of plenoptic sampling.

Figure 4 shows the experimental results of the method applied to dual-band radar systems and phased array radar systems.

Detailed ways

A specific embodiment of the present invention is given below in conjunction with the accompanying drawings. This embodiment is implemented on the premise of the technical solution of the present invention, and provides detailed implementation manners and processes, but the protection scope of the present invention is not limited to the following embodiments.

FIG. 1 is a schematic structural diagram of a multi-function radar all-optical receiving and processing system according to the present invention. Its composition includes: a multi-channel optical signal module 1, a pulsed light source 2, a first wavelength division multiplexing module 3, a photon sampling gate 4, a second wavelength division multiplexing module 5, a PD array 6, and an EDAC array 7. The specific connection relationship as follows:

When the system is used as the receiver of the phased array radar, the multi-channel optical signal module 1 includes N radar signal receiving channels, which are composed of N continuous light sources 1-1 with different wavelengths, N receiving antennas 1-2, N The electro-optical modulators 1-3 and N adjustable delay units 1-4 are formed (see Figure 2a). The first output end of the N continuous light sources 1-1 with different wavelengths is connected to the electro-optical modulator. 1-3 are connected to the first input terminals, the first output terminals of the N receiving antennas 1-2 are connected to the second input terminals of the N circuits of electro-optical modulators 1-3, and the N circuits of electro-optical modulators The first output end of the modulator 1-3 is connected to the first input end of the N-way adjustable delay unit 1-4, and the first output end of the N-way adjustable delay unit 1-4 is used as The N-channel optical signal output ends of the multi-channel optical signal module 1, the N-channel optical signal output ends of the multi-channel optical signal module 1 are respectively connected with the N-channel input ends of the first wavelength division multiplexing module 3, The first output end of the first wavelength division multiplexing module 3 is connected to the first input end of the photon sampling gate 4, and the first output end of the pulsed light source 2 is connected to the photon sampling gate 4. The second input end of the photon sampling gate 4 is connected with the first input end of the second wavelength division multiplexing module 5, and the second wavelength division multiplexing module 5 The output end is directly connected to the first input end of the single PD unit 6-1 of the PD array 6, and the first output end of the single PD unit 6-1 is connected to the described to perform data processing;

When the system is used as a receiver of multi-band radar, MIMO or other radars, the multi-channel optical signal module 1 (see Fig. 2b) includes N radar signal receiving channels, which are composed of N continuous light sources 1-5 with different wavelengths, N receiving antennas 1-6 and N circuits of electro-optical modulators 1-7, the first output ends of the N circuits of continuous light sources 1-5 with different wavelengths and the first input of the electro-optical modulators 1-7 The first output ends of the N receiving antennas 1-6 are connected to the second input ends of the N-channel electro-optical modulators 1-7, and the N-channel electro-optical modulators 1-7 An output terminal is used as the N-channel optical signal output terminal of the multi-channel optical signal module 1, and the N-channel optical signal output terminals of the multi-channel optical signal module 1 are respectively connected with the N-channel optical signal output terminals of the first wavelength division multiplexing module 3. The input end is connected, the first output end of the first wavelength division multiplexing module 3 is connected with the first input end of the photon sampling gate 4, and the first output end of the pulse light source 2 is connected to the The second input end of the photon sampling gate 4 is connected, the first output end of the photon sampling gate 4 is connected with the first input end of the second wavelength division multiplexing module 5, and the second wavelength division multiplexing module 5 is connected. The N output terminals of 5 are respectively connected with the first input terminals of the N PD units of the PD array 6, and the first output terminals of the N PD units are connected to the N EADCs of the EADC array 7. The first input ends of the units are connected to perform parallel processing of signals.

The multi-function radar all-optical receiving and processing method using the above-mentioned multi-function radar all-optical receiving and processing system includes the following steps:

_①N continuous optical carriers with different wavelengths λ ₁ , λ ₂ , ... In addition, if the system is used as the receiving unit of the N-channel _lidar , the N-channel optical signals received by the lidar can be directly used as the N-channel optical domain. The signal is multiplexed into one signal by the first wavelength division multiplexing module 3 and then performs all-optical sampling with the sampling pulse light in the photon sampling gate 4;

(2) After sampling by the photon sampling gate 4, the idle frequency optical signals λi ₁ , λi ₂ , ... λi _N of the N channels corresponding to the received optical signals of the N channels are simultaneously generated, that is, the simultaneous sampling of the N channels of received signals is realized; The second wavelength division multiplexing module 5 divides the sampled idler optical signals λi ₁ , λi ₂ , ... λi _N into N paths, passing through the N PD arrays 6 and the EADC arrays 7 respectively. The signal processing of each EADC unit completes the simultaneous parallel reception of the multi-function radar;

3. For phased array radar reception, this method is also applicable: N-path optical domain signals are firstly adjusted by the N-path adjustable delay units 1-4 for delay adjustment, and then fully processed by the photon sampling gate 4. Optical sampling, all-optical sampling generates _N channels _of idler optical signals λi ₁ , _{λi 2} ,... , _......

The working principle of the present invention is as follows:

As shown in Figure 3, a schematic diagram of the spectrum of the multi-channel radar receiving plenoptic sampling is given. N continuous optical carriers with different wavelengths are used as _N receiving channels (λ ₁ , λ ₂ , ... The photoelectric modulation is converted into N-path optical domain signals. The N-path optical domain signals are multiplexed into one signal by the first wavelength division multiplexing module 3, and act with the sampling pulse light (λ _sampling ) in the photonic nonlinear medium, and the photon sampling gate 4 realizes all-optical sampling. In addition, if the system is used as the receiving unit of the N-channel lidar, the N-channel optical signals received by the lidar can be directly used as N-channel optical domain signals, which are multiplexed into one signal by the first wavelength division multiplexing module 3 and then combined with the sampled pulsed light. Perform plenoptic sampling as described. After sampling, N-channel idler optical signals λi ₁ , λi ₂ , ... λi _N corresponding to the N-channel received optical signals are simultaneously generated, that is, simultaneous sampling of N-channel received signals is realized. The second wavelength division multiplexing module 5 divides the sampled idle frequency optical signals _{λi 1} , λi ₂ ,... In addition, for phased array radar reception, this method is also applicable: N channels of optical domain signals are first subjected to delay adjustment and then subjected to all-optical sampling. All-optical sampling generates N channels of idle-frequency optical signals, which are then subjected to wavelength division multiplexing (or filter) to simultaneously filter out _N channels of idler frequency light λi ₁ , λi ₂ , ......

Fig. 4(a) shows the experimental results in the two-channel dual-band radar receiving system, and Fig. 4(b) shows the receiving scanning pattern of the four-channel phased array radar system.

Claims (2)

1. A multifunctional radar all-optical receiving and processing system, characterized in that, comprising: a multi-channel optical signal module (1), a pulsed light source (2), a first wavelength division multiplexing module (3), a photon sampling gate (4) ), the second wavelength division multiplexing module (5), the PD array (6), and the EADC array (7). The specific connection relationship is as follows: When the system is used as the receiver of the phased array radar, the multi-channel optical signal module (1) includes N radar signal receiving channels, which are composed of N continuous light sources with different wavelengths, N receiving antennas, and N electro-optical modulators. It is composed of N channels of adjustable delay units, the first output ends of the N channels of continuous light sources with different wavelengths are connected with the first input ends of the electro-optic modulator, and the first outputs of the N receiving antennas The terminal is connected to the second input terminal of the N-channel electro-optical modulator, the first output terminal of the N-channel electro-optical modulator is connected to the first input terminal of the N-channel adjustable delay unit, the The first output end of the N-way adjustable delay unit is used as the N-way optical signal output end of the multi-channel optical signal module (1), and the N-way optical signal output of the multi-channel optical signal module (1) The terminals are respectively connected with the N input terminals of the first wavelength division multiplexing module (3), and the first output terminal of the first wavelength division multiplexing module (3) is connected to the first output terminal of the photon sampling gate (4). An input end is connected, the first output end of the pulsed light source (2) is connected with the second input end of the photon sampling gate (4), and the first output end of the photon sampling gate (4) is connected to The first input ends of the second wavelength division multiplexing module (5) are connected to each other, and the N output ends of the second wavelength division multiplexing module (5) are respectively connected to the N output ends of the PD array (6). The first input ends of the PD units are connected, and the first output ends of the N PD units are connected to the first input ends of the N EADC units of the EADC array (7) to perform parallel processing of signals; When the system is used as a multi-band radar or MIMO receiver, the multi-channel optical signal module (1) includes N radar signal receiving channels, which are composed of N continuous light sources with different wavelengths, N receiving antennas, and N electro-optical modulations. The first output end of the N channels of continuous light sources with different wavelengths is connected to the first input end of the electro-optic modulator, and the first output ends of the N receiving antennas are connected to the N channels The second input end of the electro-optical modulator is connected, and the first output end of the N-channel electro-optical modulator is used as the N-channel optical signal output end of the multi-channel optical signal module (1). The multi-channel optical signal The N-way optical signal output ends of the module (1) are respectively connected with the N-way input ends of the first wavelength division multiplexing module (3), and the first output end of the first wavelength division multiplexing module (3) is connected to the The first input end of the photon sampling gate (4) is connected, the first output end of the pulsed light source (2) is connected with the second input end of the photon sampling gate (4), and the photon sampling The first output end of the gate (4) is connected to the first input end of the second wavelength division multiplexing module (5), and the N output ends of the second wavelength division multiplexing module (5) are respectively connected with the first input end of the second wavelength division multiplexing module (5). The first input ends of the N PD units of the PD array (6) are connected, and the first output ends of the N PD units are connected to the first inputs of the N EADC units of the EADC array (7). The terminals are connected to perform parallel processing of signals; N≥1. 2. The multi-function radar all-optical receiving and processing method utilizing the multi-function radar all-optical receiving and processing system of claim 1 is characterized in that the method comprises the following steps: _①N continuous optical carriers with different wavelengths (λ ₁ , λ ₂ , ... It is used as a signal, and the sampling pulse light (λ _sampling ) acts in the photonic nonlinear medium, and realizes all-optical sampling in the photon sampling gate; The N-path optical signals can be directly used as N-path optical domain signals, and after being multiplexed into one signal by the first wavelength division multiplexing module (3), all-optical sampling is performed with the sampling pulse light in the photon sampling gate (4); ②The photon sampling gate (4) generates N-channel idler optical signals (λi ₁ , λi ₂ , ... λi _N ) corresponding to the N-channel optical domain signals of the N receiving channels simultaneously after sampling, that is, for N Simultaneous sampling is achieved for the received signals of the two channels; the idle frequency optical signals ( _{λi 1} , λi ₂ , ... The N PD units of the array (6) and the N EADC units of the EADC array (7) perform signal processing, that is, the simultaneous parallel reception of the multi-function radar is completed; 3. For phased array radar reception, this method is also applicable: N-path optical domain signals are firstly adjusted by the N-path adjustable delay unit, and then all-optical through the photon sampling gate (4). Sampling to generate _N channels of idle frequency optical signals _{(λi 1 , λi 2 ,} ... λi _N ) is simultaneously filtered out into one signal, and then through the signal processing of the single PD unit of the PD array (6) and the single EADC unit of the EADC array (7), the receiving beam of the phased array can be realized scanning.

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