Photonic-Assisted Instantaneous Frequency Measurement System Based on a Scalable Structure

We propose and demonstrate a new photonic-assisted instantaneous frequency measurement (IFM) system based on a scalable structure. By using multiple scalable modules, the proposed IFM system can achieve both large operating bandwidth and high measurement resolution. A rough measurement is given by a module with large operating bandwidth but low resolution. The final high resolution measurement is performed by other modules, which have smaller operating bandwidths but higher resolutions. By using four scalable modules simultaneously, the system achieves resolutions of ±0.1 and ±0.025 GHz for the 1-20 and 7-20 GHz frequency measurement ranges, respectively. By increasing the number of scalable modules, the resolution can be further improved.