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Photonic microwave switching for satellite communication

Microwave switching is of great importance in satellite communications to realize function switching, signal routing, and system reconfiguration. Photonic approaches to realize the microwave switching have advantages in terms of wide bandwidth, high switching speed and immunity to EMI. In this paper, we present a review on the recent advances of the photonic microwave switching for satellite communications. Particular attention is paid to the photonic microwave switching based on optical single sideband (OSSB) wavelength conversion in a semiconductor optical amplifier (SOA). The OSSB signal generation is realized simultaneously with the photonic microwave switching by using the joint self-phase modulation (SPM) and four-wave mixing (FWM) effects in the SOA. The switching crosstalk can be minimized since the OSSB signal occupies the least optical bandwidth. Channel equalities of the photonic microwave switch by use of the cross-gain modulation (XGM) in the SOA are investigated. The influence of the parameters such as the pump and probe signal power, the modulation efficiency and the SOA bias current with the performance of the photonic microwave switch are analyzed and discussed. A 2 × 2 proof-of-concept microwave photonic satellite repeater based on the photonic microwave switch is demonstrated, where stable switching of High Definition (HD) video signals with 1.5-GHz bandwidth without cross interference is successfully realized.