Relative-intensity-noise cancellation in bandpass external-modulation links

A new method of optically summing time-shifted complementary signals to cancel relative intensity noise (RIN) in narrow-band external-modulation optical links is proposed and demonstrated. Differential-link noise figure and dynamic-range improvement are compared to the conventional low-biased modulator configuration for suboctave applications. RIN suppression of 12 dB at 4 GHz is demonstrated.