A novel approach to realize broadband microwave spectrum sensing based on photonic RF channelization and compressive sampling (CS) is proposed. The photonic RF channelization system is used to slice the input broadband signal into multiple sub-channel signals with narrow bandwidth in parallel and thus the rate of pseudo-random binary sequence (PRBS) and the bandwidth of the MZM for CS can be largely decreased. It is shown that a spectrally sparse signal within a wide bandwidth can be captured with a sampling rate far lower than the Nyquist rate thanks to both photonic RF channelization and CS. In addition, the influence of the non-ideal filtering of the photonic channelizer is evaluated and a novel approach based on measuring twice is proposed to overcome the problem of frequency aliasing induced by the non-ideal filtering. It is demonstrated that a system with 20 Gbit/s PRBS and 2.5 GS/s digitizer can be used to capture a signal with multiple tones within a 40 GHz bandwidth, which means a sampling rate 32 times lower than the Nyquist rate.

中文翻译：

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基于光子射频信道化和压缩采样的宽带微波频谱传感

提出了一种基于光子射频信道化和压缩采样 (CS) 实现宽带微波频谱感知的新方法。光子射频信道化系统用于将输入的宽带信号并行切片为多个窄带宽子信道信号，从而大大降低伪随机二进制序列(PRBS)的速率和用于CS的MZM的带宽。结果表明，由于光子 RF 通道化和 CS，可以以远低于奈奎斯特速率的采样率捕获宽带宽内的频谱稀疏信号。此外，评估了光子信道器非理想滤波的影响，提出了一种基于两次测量的新方法来克服非理想滤波引起的频率混叠问题。