提出了一种将受激布里渊散射(SBS)应用于被动毫米波综合孔径成像中的方案。运用光纤SBS效应,对毫米波的抑制载波双边带(DSB—SC)调制信号的一个边带进行放大同时抑制另一个边带,实现毫米波信号的抑制载波单边带(SSB—SC)调制。将该方案应用于被动毫米波综合孔径成像中,在获得毫米波信号上变频的同时实现了光学滤波以及单边带功率放大。深入分析了SBS实现SSB~SC调制的原理以及运用于被动毫米波综合孔径成像中的可行性。实验结果表明:本文方案可以有效实现毫米波的上变频、功率放大及滤波功能;与传统电光调制系统相比,本文方案简单有效,由于系统对携带毫米波信息的边带有放大作用,可以运用于毫米波功率较低时的成像。
A method for synthetic aperture passive millimeter wave imaging based on stimulated Brillouin scattering (SBS) in optical fiber is proposed. In the system of the passive millimeter wave imaging, a singld-sideband signal carrying the amplitude and phase information of the millimeter wave is acquired in each link. In this scheme, the single-sideband suppressed-carrier modulation of the millimeter wave signal is achieved by using SBS in fiber to suppress a sideband of the modulated millimeter wave signal and to amplify another. Apparently, this technique realizes electro-optic modulation and up-conversion of the millimeter wave. Furthermore, optical filtering and amplification of the single sideband are demonstrated. Compared with traditional up-converted approaches, the sparse aperture passive imagin4g based on SBS is discussed theoretically. In addition, the viability of this scheme is rigorously analyzed. Experimental results demonstrating the viability of this scheme are Presented. Therefore, compared with traditional approaches, this scheme is simpler and more competitive. As the amplification of the single-sideband signalr s power,this system based on SBS could be used to achieve the image of the millimeter wave with lower power.