A Compact Photonic-delay Line Phase Noise Measurement System Based on an Electro-absorption Modulated Laser

An approach for phase noise measurement of microwave signal sources is proposed and experimentally demonstrated based on an electro-absorption modulated laser (EML). By replacing the laser source and intensity modulator of a conventional photonic-delay line method with a single EML, the proposed phase noise measurement system achieves low cost and simple structure, as well as maintaining high measurement accuracy. In the proof-of-concept experiment, accurate measurement of single-sideband phase noise of the 10 GHz microwave signals under test is achieved. The phase noise floor of the measurement system is below -130 dBc/Hz @ 10 kHz offset.