Microwave photonics channelized receiver with high phase stability.

Acquiring phase relationships among channels is crucial for channelized receivers to achieve large instantaneous bandwidth. In conventional technical approaches, the system exhibits significant sensitivity to environmental disturbances and fails to maintain stable phase relationships across channels, resulting in significant challenges in acquiring cross-channel phase information. Consequently, extensive additional digital signal processing is necessitated to extract the phase information of broadband signals. To mitigate these limitations, this study proposes a novel microwave photonics (MWP) channelized receiver with high phase stability based on dual optical frequency combs (OFCs). The system is meticulously designed to ensure the same phase jitter across all channels at the hardware level, thereby preserving stable phase relationships among channels. This architectural innovation significantly enhances the system's immunity to environmental disturbances. In the experimental evaluation, dual-tone signals were employed to assess the phase stability among channels within the system. The root mean square values of phase jitter among all the channels were within 1.71 degrees. Additionally, comprehensive system testing was conducted using broadband linear frequency modulation (LFM) signals and broadband quadrature phase shift keying (QPSK) signals. The received signals were successfully reconstructed. Through repeated measurements, it was demonstrated that the demodulated LFM signals exhibited stable side mode suppression ratios, while the QPSK signals yielded stable constellation diagrams post-demodulation. These experimental results conclusively validate the phase stability of the proposed system. Notably, this system represents the hardware-level implementation of a channelized receiver capable of maintaining stable phase relationships among channels based on dual OFCs. Furthermore, it has experimentally demonstrated, for the first time, the channelized reception and synthesis of a single broadband digital signal. This advancement provides a potential solution for phase-stabilized channelized reception of broadband signals, offering a robust solution for applications requiring high phase stability and large instantaneous bandwidth.