Photonic-frequency-interleaving-enabled broadband receiver with high reconfigurability and scalability

The photonic frequency-interleaving (PFI) technique has shown great potential for broadband signal acquisition, effectively overcoming the challenges of clock jitter and channel mismatch in the conventional time-interleaving paradigm. However, current comb-based PFI schemes have complex system architectures and face challenges in achieving large bandwidth, dense channelization, and flexible reconfigurability simultaneously, which impedes practical applications. In this work, we propose and demonstrate a broadband PFI scheme with high reconfigurability and scalability by exploiting multiple free-running lasers for dense spectral slicing with high crosstalk suppression. A dedicated system model is developed through a comprehensive analysis of the system non-idealities, and a cross-channel signal reconstruction algorithm is developed for distortion-free signal reconstruction, based on precise calibrations of intra- and inter-channel impairments. The system performance is validated through the reception of multi-format broadband signals, both digital and analog, with a detailed evaluation of signal reconstruction quality, achieving inter-channel phase differences of less than 2°. The reconfigurability and scalability of the scheme are demonstrated through a dual-band radar imaging experiment and a three-channel interleaving implementation with a maximum acquisition bandwidth of 4 GHz. To the best of our knowledge, this is the first demonstration of a practical radio-frequency (RF) application enabled by PFI. Our work provides an innovative solution for next-generation software-defined broadband RF receivers.