Investigation of a balanced microwave photonic link utilizing a single few-mode fiber

Abstract

A balanced microwave photonic link, which utilizes mode-division multiplexing in order to combine both of its optical paths into and out of a single six-mode few-mode fiber, is demonstrated for the first time, to the best of our knowledge. Due to non-negligible modal crosstalk, the link exhibited excess radio-frequency gain fluctuations when compared to an equivalent conventional balanced link. The L P 02 + L P 01 mode pair was the most stable with 2 σ (two standard deviations) fluctuations of 0.4 dB about the average link gain, compared to the conventional link’s 2 σ of 0.16 dB. The excess crosstalk-induced fluctuations may render the link impractical to use outside of the laboratory.