High Power Optical Amplifier

The objective of this proposal is to develop innovative highly reliable HPOA for free space laser communications based SATCOM operating over broad ranges of temperatures and of radiation environment. The Phase I effort is focused on investigating the feasibility of manufacturing of such a HPOA by means of simulating and designing the amplifier for the desired optical specs as well as modeling and designing optic/electronic components and packaging for the required reliability specs. Our proposed design is based on two stage rare earth doped fiber amplifier. The first stage is a pre-amplifier with a low noise figure (i.e. 3dB), while the second stage is a high power amplifier based on a doped double clad fiber that would provide high output power (i.e. >500mW) in saturation when pumped with multimode pumps. In order to meet bandwidth requirement of 1500nm and 1450nm in additon to 1550nm, the HPOA designs based on amplified spontaneous emission filtering in Er/Yb doped and based on Thulium double clad fiber will also be investigated for 1470-1520nm and 1450-1480nm, respectively. The proposed HPOAs consist of COTS components that have been widely used in telecommunications with proven reliability in terms of power handling and life time. In addition to Telecordia standards where the minimum operation temperature is 0C, pump lasers’ temperature controller circuitry will be modified to accommodate an operation temperature down to -40C utilizing our patented ultralow power consumption circuitry designs as means to minimize required operation power and associated thermal management issue. The proposed aluminum/PolyRAD packaging will be modeled and designed utilizing the radiation modeling code, NOVICE, to meet the radiation shield specs, as well as utilizing thermal modeling tool, COSMOSM, to provide thermal management.. The projected dimensions and weight of the proposed HPOA are 15x12x4cm3 and 1.8lb, respectively.