Amplitude Noise Limiting Amplifier for Phase Encoded Signals Using Injection Locking in Semiconductor Lasers

In this study, a phase-preserving limiter based on injection locking a semiconductor laser is fully investigated as an amplitude limiter for 10 Gb/s constant envelope phase encoded signals. A theoretical analysis on the modulation bandwidth and the modulation transfer function of the injection locked laser is carried out targeting to identify the operational characteristics and the regeneration properties of the proposed amplitude limiter. The theoretical analysis demonstrates the potential of the specific limiter to amplify 25 Gbaud phase modulated signals with simultaneous regeneration of its amplitude properties. Subsequently an experimental investigation demonstrates the performance of the proposed regenerator and addresses its potential exploitation in future optical networks. The specific limiter exhibits significant amplitude noise squeezing capability and extreme implementation simplicity.