Fully On‐Chip Microwave Photonic Instantaneous Frequency Measurement System

Microwave photonics (MWP) is an emerging field that studies the interaction between microwave and lightwave for myriad communication and information applications. Recently, new opportunity for MWP has emerged driven by the advances of integrated photonics. However, despite significant progress made in terms of integration level, a fully on-chip MWP functional system comprising all the necessary photonic and electronic components, is yet to be demonstrated. Here, the status quo is broken and a complete on-chip solution for MWP system is provided, by exploiting hybrid integration of indium phosphide, silicon photonics, and complementary metal-oxide-semiconductor electronics platforms. Applying this hybrid integration methodology, a fully chip-based MWP instantaneous frequency measurement (IFM) system is demonstrated. The unprecedented integration level brings great promotion to the compactness, reliability and performances of the MWP IFM system, including a wide frequency measurement range (2-34 GHz), ultralow estimation errors (10.85 MHz), and a fast response speed (approximate to 0.3 ns). Furthermore, the chip-scale MWP IFM system is deployed into realistic tasks, where diverse microwave signals with rapid-varying frequencies at X-band (8-12 GHz) are accurately identified in real-time. This demonstration marks a milestone for the integrated MWP, by providing the technology basis for the miniaturization and massive implementations of various MWP systems.