Open AccessPhotonic microwave waveform generation based on phase modulation and tunable dispersion
Author(s) -
Yongsheng Gao,
Aijun Wen,
Hanxiao Zheng,
Liang Dong,
Lin Lin
Publication year - 2016
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.24.012524
Subject(s) - waveform , optics , arbitrary waveform generator , phase modulation , microwave , bandwidth (computing) , photonics , duty cycle , signal generator , signal (programming language) , modulation (music) , materials science , optoelectronics , physics , phase noise , telecommunications , computer science , power (physics) , radar , acoustics , chip , quantum mechanics , programming language
Photonic generation of microwave waveforms is currently an interesting topic due to the advantages of large bandwidth and immunity to electromagnetic interference. In this paper, a photonic microwave waveform generator with tunable waveforms and repetition rates is proposed and experimentally demonstrated. A continuous-wave (CW) light is phase modulated by a local oscillator (LO) signal to generate optical sidebands. By locating the phase modulator (PM) in a Sagnac loop, we can control the intensity and phase of the carrier of the phase modulated signal. Then a compact tunable dispersion compensation module is used to introduce phase shifts to the optical sidebands. Thanks to the flexible controlling of the optical signal, the generation of microwave waveforms with tunable shapes and repetition rates can be realized. In the demonstration experiment, full-duty-cycle triangular and square waveforms with repetition rates of 5 and 10 GHz (bandwidths of 15 and 30 GHz) are successfully generated, respectively. The bandwidths are expected to be improved to above 120 GHz if larger-bandwidth measurement instruments are used. In addition to the flexible tunability, the proposed scheme also features the advantages of easy implementation and free from bias drift.