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.