In this Small Business Innovative Research (SBIR) Phase I proposal LinCom Corporation describes how state-of-the-art coding and modulation techniques can be used to increase the data rate on the Space Ground Link System (SGLS). LinCom describes how punctured Turbo Codes can be concatenated with Reed-Solomon Codes to provide coding gains for increased data throughput for those SGLS links that are power limited. For the SGLS links that are band limited, LinCom identifies how bandwidth efficient modulations such as Gaussian Minimum Shift Keying (GMSK) can be used to increase throughput. Together these techniques can double the data rate for the SGLS carrier 2 downlink. Finally, LinCom presents an innovative technique for seamlessly modifying coding/data rate by using coding to directly measure link performance. This technique allows data rate to vary as link conditions change
