光子辅助压缩感知技术关键问题研究

为了保证光子辅助压缩感知系统在获取宽带信号的过程中,测量矩阵保持零均值,采用基于马赫-曾德尔调制器的并行结构,以实现待处理信号与零均值随机序列的混频;同时采用数字域后补偿的方式,改善了强度调制器非线性对系统恢复效果的负面影响,在一定范围内提升了系统的恢复效果。结果表明,改进后的光子辅助压缩感知结构在获取宽带射频稀疏信号时,具有更好的恢复效果。

Research of key issues of photonic-assisted compressive sensing technology

In order to ensure the zero-mean property of measurement matrix during the process of acquiring wideband signal by using photonic compressive sensing, a parallel structure based on Mach-Zehnder modulators was used to implement the mixing function of input signal and zero-mean random sequence. At the same time, digital domain compensation was employed to reduce the negative effect of modulator nonlinearity on recovery performance. In this way the system had an improved recovery performance within a certain range. The results show that the improved photonic compressive sensing performs better when acquiring wideband sparse signals.