Highly sensitive, high dynamic range OLNA for single digit photons per bit in space applications

High gain optical amplifiers with low noise are desirable to pre-amplify free-space optical communications signals to usable levels prior to detection without causing significant distortion of the data stream. We report design characteristics and performance of an Optical Low Noise Amplifier (OLNA) for space applications which meet the growing needs of government and industry. Our OLNA technology features high gain ⪆ 60 dB for input powers as low as ⪅ -60 dBm, can operate without optical damage at input powers ⪆ -10 dBm, and has demonstrated noise figures ≤ 4.3 dB (3.8 dB without input isolator) in a non-PM architecture across the 1540-1560 nm band. The system architecture is specifically designed for long-term operation in space environments. Results will be presented verifying the performance of the OLNA through spectral noise figure measurements as well as testing using a variety of communications formats and data rates.