基于微波光子I/Q去斜接收的宽带线性调频雷达成像系统
|
摘要
该文提出一种新的基于微波光子I/Q去斜接收的宽带线性调频雷达成像系统方案。发射机利用微波光子倍频技术产生宽带线性调频信号,接收机利用偏分复用-双驱动马赫曾德尔调制器,将回波信号同时输入到两个不同偏振态的调制器上,并通过调节对应调制器的偏置电压在两偏振态之间引入90°相位差,从而实现微波光子I/Q去斜接收。此雷达在具备实时高分辨探测能力的同时,能区分参考点两侧的目标,解决了现有微波光子雷达接收机采用光子混频去斜接收中受镜频干扰导致距离向模糊的问题。该文首先论证了采用I/Q去斜接收的必要性,随后介绍了所提出的微波光子雷达结构与原理,最后开展了目标探测与逆合成孔径雷达成像的实验研究。该雷达工作在K波段,带宽为8 GHz。结果表明该系统可以有效解决镜频干扰引起的距离向模糊。
We propose a novel scheme of broadband LFM radar imaging system based on microwave photonic I/Q de-chirping. In the transmitter, a broadband linear frequency modulated signal is generated by photonic frequency-doubling. In the receiver, echoes reflected from the target are simultaneously sent to a couple of modulators in two polarization states. After the bias voltage of the corresponding modulator is adjusted to introduce a 90° phase difference, photonic I/Q de-chirping reception of radar echoes is achieved. The proposed radar is capable of real-time high-resolution detection and can distinguish the target on both sides of a reference point. The range ambiguity problem caused by image interference in current radar with photonic de-chirping reception is solved. In this study, first, the necessity of I/Q de-chirping is demonstrated. Then, the structure and principle of the proposed photonic-based radar are introduced. A K-band radar with a bandwidth of 8 GHz is established, and an experiment on target detection and inverse synthetic aperture radar imaging is conducted. Results show that the system can effectively suppress the interference from image frequencies.
We propose a novel scheme of broadband LFM radar imaging system based on microwave photonic I/Q de-chirping. In the transmitter, a broadband linear frequency modulated signal is generated by photonic frequency-doubling. In the receiver, echoes reflected from the target are simultaneously sent to a couple of modulators in two polarization states. After the bias voltage of the corresponding modulator is adjusted to introduce a 90° phase difference, photonic I/Q de-chirping reception of radar echoes is achieved. The proposed radar is capable of real-time high-resolution detection and can distinguish the target on both sides of a reference point. The range ambiguity problem caused by image interference in current radar with photonic de-chirping reception is solved. In this study, first, the necessity of I/Q de-chirping is demonstrated. Then, the structure and principle of the proposed photonic-based radar are introduced. A K-band radar with a bandwidth of 8 GHz is established, and an experiment on target detection and inverse synthetic aperture radar imaging is conducted. Results show that the system can effectively suppress the interference from image frequencies.
引文
[1]潘时龙,张亚梅.微波光子雷达及关键技术[J].科技导报,2017,35(20):36-52.doi:10.3981/j.issn.1000-7857.2017.20.004.PAN Shilong and ZHANG Yamei.Microwave photonic radar and key technologies[J].Science&Technology Review,2017,35(20):36-52.doi:10.3981/j.issn.1000-7857.2017.20.004.
[2]ZOU Weiwen,ZHANG Hao,LONG Xin,et al.All-optical central-frequency-programmable and bandwidth-tailorable radar[J].Scientific Reports,2016,6:19786.doi:10.1038/srep19786.
[3]XIAO Xuedi,LI Shangyuan,CHEN Boyu,et al.Amicrowave photonics-based inverse synthetic aperture radar system[C].Proceedings of 2017 Conference on Lasers and Electro-Optics,San Jose,California,2017:1-2.doi:10.1364/CLEO_AT.2017.JW2A.144.
[4]GHELFI P,LAGHEZZA F,SCOTTI F,et al.A fullyphotonics-based coherent radar system[J].Nature,2014,507 (7492):341-345.doi:10.1038/nature13078.
[5]GHELFI P,LAGHEZZA F,SCOTTI F,et al.Photonics for radars operating on multiple coherent bands[J].Journal of Lightwave Technology,2016,34(2):500-507.doi:10.1109/JLT.2015.2482390.
[6]ZHOU Pei,ZHANG Fangzheng,GUO Qingshui,et al.Linearly chirped microwave waveform generation with large time-bandwidth product by optically injected semiconductor laser[J].Optics Express,2016,24(16):18460-18467.doi:10.1364/OE.24.018460.
[7]TONG Yitian,HAN Daming,CHENG Ran,et al.Photonics-based coherent wideband linear frequency modulation pulsed signal generation[J].Optics Letter,2018,43(5):1023-1026.doi:10.1364/OL.43.001023.
[8]MIDDLETON C,MEREDITH S,PEACH R,et al.Photonic frequency conversion for wideband RF-to-IFdown-conversion and digitization[C].Proceedings of 2011IEEE Avionics,Fiber-Optics and Photonics Technology Conference,San Diego,CA,USA,2011:115-116.doi:10.1109/AVFOP.2011.6082154.
[9]CHAN E H W and MINASIAN R A.Microwave photonic downconversion using phase modulators in a sagnac loop interferometer[J].IEEE Journal of Selected Topics in Quantum Electronics,2013,19(6):3500208.doi:10.1109/JSTQE.2013.2263119.
[10]GAO Yongsheng,WEN Aijun,ZHANG Huixing,et al.An efficient photonic mixer with frequency doubling based on a dual-parallel MZM[J].Optics Communications,2014,321:11-15.doi:10.1016/j.optcom.2014.01.065.
[11]YE Xingwei,ZHANG Fangzheng,and PAN Shilong.Compact optical true time delay beamformer for a 2Dphased array antenna using tunable dispersive elements[J].Optics Letters,2016,41(17):3956-3959.doi:10.1364/OL.41.003956.
[12]LI Ruoming,LI Wangzhe,DING Manlai,et al.Demonstration of a microwave photonic synthetic aperture radar based on photonic-assisted signal generation and stretch processing[J].Optics Express,2017,25(13):14334-14340.doi:10.1364/OE.25.014334.
[13]ZHANG Fangzheng,GUO Qingshui,WANG Ziqian,et al.Photonics-based broadband radar for high-resolution and real-time inverse synthetic aperture imaging[J].Optics Express,2017,25(14):16274-16281.doi:10.1364/OE.25.016274.
[14]PENG Shaowen,LI Shangyuan,XUE Xiaoxiao,et al.Highresolution W-band ISAR imaging system utilizing a logicoperation-based photonic digitalto-analong comverter[J].Opticis Express,2018,26(2):1978-1987.doi:10.1364/OE.26.001978.
[15]ZHANG Fangzheng,GUO Qingshui,and PAN Shilong.Photonics-based real-time ultra-high-range-resolution radar with broadband signal generation and processing[J].Scientific Reports,2017,7:13848.doi:10.1038/s41598-017-14306-y.
[16]ZHANG Fangzheng,GUO Qingshui,ZHANG Ying,et al.Photonics-based real-time and high-resolution ISAR imaging of non-cooperative target[J].Chinese Optics Letters,2017,15(11):112801.doi:10.3788/col201715.112801.
[17]ZHANG Fangzheng,GAO Bingdong,and PAN Shilong.Photonics-based MIMO radar with high-resolution and fast detection capability[J].Optics Express,2018,26(13):17529-17540.doi:10.1364/OE.26.017529.
[18]YE Xingwei,ZHANG Fangzheng,YANG Yue,et al.Photonics-based radar transceiver for full-polarimetric inverse synthetic aperture imaging[C].Proceedings of 2018International Topical Meeting on Microwave Photonics(MWP),Toulouse,France,2018:1-4.doi:10.1109/MWP.2018.8552850.
[19]MENG Ziyi,LI Jianqiang,YIN Chunjing,et al.Dual-band dechirping LFMCW radar receiver with high image rejection using microwave photonic I/Q mixer[J].Optics Express,2017,25(18):22055-22065.doi:10.1364/OE.25.022055.
[20]GAO Yongshen,WEN Aijun,ZHANG Wu,et al.Ultrawideband photonic microwave I/Q mixer for zero-IFreceiver[J].IEEE Transactions on Microwave Theory and Techniques,2017,65(11):4513-4525.doi:10.1109/tmtt.2017.2695184.
[21]RICHARDS M A.Fundamentals of Radar Signal Processing[M].2nd ed.,New York:McGraw-Hill,2014:87-112.
[2]ZOU Weiwen,ZHANG Hao,LONG Xin,et al.All-optical central-frequency-programmable and bandwidth-tailorable radar[J].Scientific Reports,2016,6:19786.doi:10.1038/srep19786.
[3]XIAO Xuedi,LI Shangyuan,CHEN Boyu,et al.Amicrowave photonics-based inverse synthetic aperture radar system[C].Proceedings of 2017 Conference on Lasers and Electro-Optics,San Jose,California,2017:1-2.doi:10.1364/CLEO_AT.2017.JW2A.144.
[4]GHELFI P,LAGHEZZA F,SCOTTI F,et al.A fullyphotonics-based coherent radar system[J].Nature,2014,507 (7492):341-345.doi:10.1038/nature13078.
[5]GHELFI P,LAGHEZZA F,SCOTTI F,et al.Photonics for radars operating on multiple coherent bands[J].Journal of Lightwave Technology,2016,34(2):500-507.doi:10.1109/JLT.2015.2482390.
[6]ZHOU Pei,ZHANG Fangzheng,GUO Qingshui,et al.Linearly chirped microwave waveform generation with large time-bandwidth product by optically injected semiconductor laser[J].Optics Express,2016,24(16):18460-18467.doi:10.1364/OE.24.018460.
[7]TONG Yitian,HAN Daming,CHENG Ran,et al.Photonics-based coherent wideband linear frequency modulation pulsed signal generation[J].Optics Letter,2018,43(5):1023-1026.doi:10.1364/OL.43.001023.
[8]MIDDLETON C,MEREDITH S,PEACH R,et al.Photonic frequency conversion for wideband RF-to-IFdown-conversion and digitization[C].Proceedings of 2011IEEE Avionics,Fiber-Optics and Photonics Technology Conference,San Diego,CA,USA,2011:115-116.doi:10.1109/AVFOP.2011.6082154.
[9]CHAN E H W and MINASIAN R A.Microwave photonic downconversion using phase modulators in a sagnac loop interferometer[J].IEEE Journal of Selected Topics in Quantum Electronics,2013,19(6):3500208.doi:10.1109/JSTQE.2013.2263119.
[10]GAO Yongsheng,WEN Aijun,ZHANG Huixing,et al.An efficient photonic mixer with frequency doubling based on a dual-parallel MZM[J].Optics Communications,2014,321:11-15.doi:10.1016/j.optcom.2014.01.065.
[11]YE Xingwei,ZHANG Fangzheng,and PAN Shilong.Compact optical true time delay beamformer for a 2Dphased array antenna using tunable dispersive elements[J].Optics Letters,2016,41(17):3956-3959.doi:10.1364/OL.41.003956.
[12]LI Ruoming,LI Wangzhe,DING Manlai,et al.Demonstration of a microwave photonic synthetic aperture radar based on photonic-assisted signal generation and stretch processing[J].Optics Express,2017,25(13):14334-14340.doi:10.1364/OE.25.014334.
[13]ZHANG Fangzheng,GUO Qingshui,WANG Ziqian,et al.Photonics-based broadband radar for high-resolution and real-time inverse synthetic aperture imaging[J].Optics Express,2017,25(14):16274-16281.doi:10.1364/OE.25.016274.
[14]PENG Shaowen,LI Shangyuan,XUE Xiaoxiao,et al.Highresolution W-band ISAR imaging system utilizing a logicoperation-based photonic digitalto-analong comverter[J].Opticis Express,2018,26(2):1978-1987.doi:10.1364/OE.26.001978.
[15]ZHANG Fangzheng,GUO Qingshui,and PAN Shilong.Photonics-based real-time ultra-high-range-resolution radar with broadband signal generation and processing[J].Scientific Reports,2017,7:13848.doi:10.1038/s41598-017-14306-y.
[16]ZHANG Fangzheng,GUO Qingshui,ZHANG Ying,et al.Photonics-based real-time and high-resolution ISAR imaging of non-cooperative target[J].Chinese Optics Letters,2017,15(11):112801.doi:10.3788/col201715.112801.
[17]ZHANG Fangzheng,GAO Bingdong,and PAN Shilong.Photonics-based MIMO radar with high-resolution and fast detection capability[J].Optics Express,2018,26(13):17529-17540.doi:10.1364/OE.26.017529.
[18]YE Xingwei,ZHANG Fangzheng,YANG Yue,et al.Photonics-based radar transceiver for full-polarimetric inverse synthetic aperture imaging[C].Proceedings of 2018International Topical Meeting on Microwave Photonics(MWP),Toulouse,France,2018:1-4.doi:10.1109/MWP.2018.8552850.
[19]MENG Ziyi,LI Jianqiang,YIN Chunjing,et al.Dual-band dechirping LFMCW radar receiver with high image rejection using microwave photonic I/Q mixer[J].Optics Express,2017,25(18):22055-22065.doi:10.1364/OE.25.022055.
[20]GAO Yongshen,WEN Aijun,ZHANG Wu,et al.Ultrawideband photonic microwave I/Q mixer for zero-IFreceiver[J].IEEE Transactions on Microwave Theory and Techniques,2017,65(11):4513-4525.doi:10.1109/tmtt.2017.2695184.
[21]RICHARDS M A.Fundamentals of Radar Signal Processing[M].2nd ed.,New York:McGraw-Hill,2014:87-112.