Chromatic dispersion immune microwave photonic phase shifter based on double-sideband modulation

A chromatic dispersion (CD) immune microwave photonic phase shifter (MPPS) based on double-sideband (DSB) modulation is proposed and demonstrated. An optical spectrum processor introduces the phase shift to the MPPS. The DSB signals along two orthogonal polarizations are demodulated to two RF signals with both quadrature amplitude and phase items, transferring the CD-induced power fading to the phase item of the synthetic RF signals. Experimental results show that the RF signals over 14-25 GHz obtain random phase shift in 360° range without a power fading point (PFP) after passing through a dispersion compensation fiber with CD of -331  ps/nm. The phase variation and power variation of the phase-shifted signal are <±5.7° and <±0.9  dB, respectively, at the original PFP at 16 GHz.