基于双驱动DP-MZM的倍频双啁啾信号产生方法  

Frequency-multiplying Dual-chirp Microwave WaveformGeneration Based on a Dual-drive DP-MZM

作　　者：张昆[1] 赵尚弘[1] 林涛[1] 王国栋 李赫 李轩[1] 朱子行[1] ZHANG Kun;ZHAO Shanghong;LIN Tao;WANG Guodong;LI Hai;LI He;LI Xuan;ZHU Zihang(College of Information and Navigation,Air Force Engineering University,Shaanxi,Xi’an 710077,China)

机构地区：[1]空军工程大学信息与导航学院,西安710077

出　　处：《空间电子技术》2020年第4期109-116,共8页Space Electronic Technology

基　　金：国家自然科学基金(61571461);陕西省自然科学基金(2019JQ707)。

摘　　要：提出了一种基于双驱动双平行马赫增德尔调制器(DP-MZM)的倍频双啁啾线性调频(LFM)信号产生方法。方案中,DP-MZM的上臂受射频驱动,产生偶数阶光边带;下臂受基带信号调制,产生单边带光信号。合理地设置驱动信号的调制系数和主调制器的直流相移,可抑制DP-MZM输出光信号中的载波分量。耦合光信号平方率检波后,可产生载波二倍频、带宽四倍频的双啁啾LFM信号。实验验证了所提方案的可行性,获得了载频14 GHz、带宽1.6 GHz、时宽带宽积1600的双啁啾LFM信号。对波形进行自相关处理,1μs的波形被压缩至0.762 ns,对应脉冲压缩比为1312。所提方案无需偏振器件和光滤波器,具有操作简单、调谐性高的优势,产生信号表现出好的旁瓣抑制性能和脉冲压缩性能。利用模糊函数分析了产生信号对雷达距离-多普勒模糊的改善,搭建了运动目标场景验证了产生信号的探测性能。Frequency-multiplying dual-chirp linearly frequency modulated(LFM)signals generator based on a dual-drive dual-parallel Mach-Zehnder modulator(DP-MZM)is demonstrated.In the approach,upper arm of the DP-MZM is driven by an RF signal to generate even-order sideband signal.Lower arm of the DP-MZM is driven by a baseband signal to generate single sideband optical signal.The carrier component of DP-MZM can be suppressed by adjusting the modulation indices of the drive signals and the DC phase shift of the main modulator reasonably.After square-law detection of coupled optical signals,dual-chirp LFM signals with carrier frequency-double and bandwidth-quadruple can be generated.Experiments verify the feasibility of the proposed scheme,and dual-chirped LFM signals with carrier frequency of 14 GHz,bandwidth of 1.6 GHz and time-bandwidth product of 1600 are obtained.Waveforms of the dual-chirp signals are auto-correlated.Waveform with time duration of 1μs is compressed to 0.762 ns,corresponding a pulse compression ratio of 1312.The proposed approach has the advantages of simple operation and high tunability for no polarization device and optical filter involved,and the generated signals show good sidelobe suppression and pulse compression performance.The improvement of range-Doppler coupling is analyzed by using the ambility function,and the detection performance of the generated signal is verified by build moving target scenes.

关 键 词：微波光子雷达 双啁啾信号 双平行马赫增德尔调制器 探测精度 

分 类 号：TN98[电子电信—信息与通信工程]