Modulation-Averaging Reflectors for Extended-Cavity Optical Sources

We propose and theoretically analyze a novel transmitter emitting m wavelength-division multiplexed and independently modulated optical signals. The transmitter is based on an extended cavity formed by m wavelength-agnostic reflective semiconductor optical amplifiers (one for each wavelength) on one end and a single modulation-averaging reflector on the other end of the cavity. We show that optimally designed modulation-averaging reflectors can efficiently change the intensity probability density function from bound bit-stream modulation to a normal distribution and thereby improve signal-to-noise ratio of all emitted optical signals. This improvement may potentially allow the realization of cost-efficient wavelength division multiplexing passive optical networks (WDM-PON).