Enhanced Amplitude Noise Tolerance of a Self-Seeded RSOA Laser Using Balanced Detection

Self-seeded cavity lasers appear as attractive colorless sources for dense wavelength division multiplexed passive optical networks. Although this technology has already demonstrated high performance in a number of experiments, the strong multimode behavior of these kilometer-long cavities results in large relative intensity noise (RIN) that can become the main limiting factor for transmission. In this letter, we correlate the transmission performance degradation to the RIN increase when the cavity length increases. We evidence a better tolerance to amplitude noise when a combination of Manchester encoding and balanced detection is used in a proof-of-concept experiment. Using this combination, the cavity length can be four times longer than when using standard non-return-to-zero encoding for the same bit-error-rate performance.