High Power (50W), 1.5um WDM Fiber Laser Transmitter with Effective FWM Mitigation

NASArsquo;s Space Communications and Navigation (SCaN) roadmap for 2025 and beyond shows the need for optical links for Earth, lunar, inter-planetary, and relay networks requiring 10-100x higher data rates than current state-of-the-art space-based optical communications systems. Future laser communications system requirements include data rates gt;1 Gbps downlink from planetary bodies, and gt;100 Gbps low-geosynchronous earth orbit (LEO-GEO) networks. To support high-data-rate communications for long-range GEO and inter-planetary missions, a new class of laser communications transmitter is required with high average power (gt;20 W), high efficiency (gt;20%), and high peak power (gt;1 kW)mdash;and capable of 16-ary and 128-ary pulse position modulation (PPM) formats. Wavelength-division multiplexed (WDM) systems must also have output power that is spectrally flat with minimal cross-talk.Fibertek proposes to develop and demonstrate a high lambda;-channel count (up to 20 channels), gain-flat, high power, spaceflight prototype transmitter with an innovative Four Wave Mixing (FWM) mitigation capability or deep space optical communication (DSOC) links.nbsp; High power, multi-wavelength channel fiber amplifiers are fundamentally limited in channel count scaling to 4 channels and power scaling due to FWM non-linearities causing Pulse Energy Variation (PEV).nbsp; Our innovative approach effectively mitigates FWM resulting in compact, efficient, reliable and space-qualifiable system.nbsp; These enhancements increase the data capacity scaling by gt;10x over the current state of the art high power WDM transmitter enabling the next generation of high speed DSOC links.m.