No abstract

A self-oscillating optical frequency comb (OFC) generator is designed and experimentally demonstrated using an electro-absorption modulated laser based optoelectronic oscillator and a recirculating frequency shifter. A 10-GHz 38-tone OFC is generated with a 1.2-dB flatness.

A scheme for multi‐band frequency generation is proposed and experimentally demonstrated using a dual‐parallel Mach–Zehnder modulator (DPMZM)‐based optoelectronic oscillator (OEO). The principle of this generator is theoretically described in detail. It is found that multiple frequencies with a small power variation can be produced by setting the three working points and the modulation depth of the DPMZM. In the proving experiment, an 8‐GHz fundamental oscillation with a side mode suppression ratio of 44 dB is generated. The phase noise is measured to be −96.8 dBc/Hz @ 10 KHz offset with a 100‐m and 1‐Km optical fibre used in the two oscillation loops. When the oscillating signal is applied to drive the two sub‐modulators in the DPMZM, doubled and tripled frequencies are produced at the same time, and the phase noises of the two frequencies are also measured to be −90.2 dBc/Hz and −85.9 dBc/Hz @10 KHz, respectively.

A scheme for binary phase-coded microwave signal generation is proposed and experimentally demonstrated with a dual-parallel Mach–Zehnder modulator (DPMZM). The carrier of the generated phase-coded signal is provided by the built-in dual-loop optoelectronic oscillator (OEO) based on the DPMZM. The principle of this signal generator and the oscillating condition of the OEO is theoretically described in detail. It is found that phase-coded signals can be produced by setting the three working points and the modulation depth of the DPMZM. In the proving experiment, a 10-GHz oscillating signal with a side mode suppression ratio of 49 dB is generated. The phase noise of this carrier wave is measured to be − 80 d B c / H z at 10 kHz offset with a 100-m and 1-km optical fiber used in the two oscillation loops. When 1-Gbit/s and 2-Gbit/s coding signals are, respectively, applied to the DPMZM, two 10-GHz self-oscillating phase-coded signals are eventually produced, and the π phase shift in the signals is successfully confirmed with the phase information extracted from the phase-coded signals.