Full-spectrum covering ultra wideband all photonics-based radar system

Patent metadata

Field	Value
Publication number	US-2018106904-A1
Application number	US-201715833992-A
Country	US
Kind code	A1
Filing date	Dec 6, 2017
Priority date	Aug 17, 2015
Publication date	Apr 19, 2018
Grant date	—

Abstract

A full-spectrum covering ultra wideband full-photonics based radar system comprising a signal transmitter, a transceiver module, and a signal receiver. The signal transmitter comprises a mode-locked laser, a first dispersion module, a first optical coupler, a second optical coupler, a first optical filter, a second dispersion module, a second optical filter, a first adjustable time delay module, a third optical coupler, an optical amplifier, and a first photodetector; the transceiver module comprises a band selector, a first electrical amplifier array, a T/R component array, an antenna array, and a second electrical amplifier array; the signal receiver comprises a third optical filter, a second adjustable time delay module, an electro-optical modulator, a third dispersion module, a second photodetector, an analog-digital conversion module, and a signal processing module. The system has continuous tunability for center frequency, bandwidth, and time width of the wideband signal with high coherence and ranging accuracy.

First claim

We claim:

1 . A full-spectrum covering ultra wideband full-photonics based radar system, comprising
a signal transmitter, the signal transmitter further comprising
a mode-locked laser having an output end,
a first dispersion module,
a first optical coupler having an input end, a first output end, and a second output end,
a second optical coupler having an input end,
a first optical filter having a filtering bandwidth,
a second dispersion module,
a second optical filter having a filtering bandwidth,
a first tunable time delay module,
a third optical coupler having an input end,
an optical amplifier, and
a first photodetector,
a transceiver module, the transceiver module further comprising
a band selector having an input end and more than two output ends,
a first electrical amplifier array having electrical amplifiers,
a T/R component array having T/R components,
an antenna array having antennas, and
a second electrical amplifier array, and
a signal receiver, the signal receiver further comprising
a third optical filter having a filtering bandwidth,
a second tunable time delay module,
an electro-optical modulator having an rf input end and an optical input end,
a third dispersion module,
a second photodetector,
an analog-digital conversion module, and
a signal processing module,
wherein the output end of the mode-locked laser is connected via the first dispersion module with the input end of the first optical coupler, and the first output end of the first optical coupler is connected with the input end of the second optical coupler; the second optical coupler splits an optical path into a first optical path and a second optical path, with the first optical path traversing successively the first optical filter and the second dispersion module till the input end of the third optical coupler, and the second optical path traversing successively the second optical filter and the first tunable time delay module till the input end of the third optical coupler; the third optical coupler couples a signal of the first optical path and of the second optical path respectively into one optical signal and outputs via the optical amplifier to enter the first photodetector; the first photodetector converts the optical signal into an electrical signal and inputs to the input end of the band selector of the transceiver module, each of the output ends of the band selector is connected successively with the respective electrical amplifier of the first electrical amplifier array, the respective T/R component of the T/R component array, and the respective antenna of the antenna array, to form a channel for a respective waveband; an echo signal of an electrical signal transmitted from the antenna array is returned by a to-be-detected target and passes successively via the respective antenna of the antenna array, the respective T/R component of the T/R array, and the second electrical amplifier array to form a target echo electrical signal to be inputted to the rf input end of the electro-optical modulator; an optical signal of the second output end of the first optical coupler successively passes via the third optical filter and the second tunable time delay module to be inputted into the optical input end of the electro-optical modulator to form an optical pulse carrier wave; the electro-optical modulator loads the target echo electrical signal onto the optical pulse carrier wave to form an echo modulation optical signal corresponding to the target echo electrical signal, with the echo modulation optical signal of the electro-optical modulator successively passing via the third dispersion module, the second photodetector, and the analog-digital conversion module to enter the signal processing module.

2 . The full-spectrum covering ultra wideband full-photonics based radar system of claim 1 , wherein the mode-locked laser is a mode-locked laser with low jitter and wide spectrum.

3 . The full-spectrum covering ultra wideband full-photonics based radar system of claim 1 , wherein the filtering bandwidth of the third optical filter is greater than the filtering bandwidth of the first optical filter and the filtering bandwidth of the second optical filter.

4 . The full-spectrum covering ultra wideband full-photonics based radar system of claim 2 , wherein the filtering bandwidth of the third optical filter is greater than the filtering bandwidth of the first optical filter and the filtering bandwidth of the second optical filter.

Assignees

• Univ Shanghai Jiaotong

Inventors

• Zou Weiwen
• Zhang Hao
• Zhang Siteng
• Chen Jianping

Classifications

• G01S7/28

  Details of pulse systems · CPC title

• G01S13/26

  wherein the transmitted pulses use a frequency- or phase-modulated carrier wave · CPC title

• G01S17/88 Primary

  Lidar systems specially adapted for specific applications · CPC title

• G01S13/0209

  Systems with very large relative bandwidth, i.e. larger than 10 %, e.g. baseband, pulse, carrier-free, ultrawideband · CPC title

• G01S7/03 Primary

  Details of HF subsystems specially adapted therefor, e.g. common to transmitter and receiver · CPC title