BANDWIDTH EFFICIENT MODULATION SCHEMES FOR FUTURE TT&C APPLICATIONS

This paper presents initial results of an investigation on bandwidth efficient waveforms for telemetry, tracking and commands (TT&C). Included in the investigation are waveforms that are currently being considered by the International Consultative Committee for Space Data Systems (CCSDS) and American Institute of Aeronautics and Astronautics (AIAA) for standards, advanced waveforms and others that have the potential to become future standards. The goal of this investigation is to recommend a suite of bandwidth efficient modulation schemes for further investigation. This suite of modulation scheme should be suitable for various TT&C applications with data rates ranging from a few hundreds Bit Per Second (bps) to a few hundreds Mega bps (Mbps). First, the philosophy of waveform evaluation is described. The description includes a list of waveform attributes leading to quantitative and qualitative figures of merit for bandwidth efficient waveforms. Then quantitative results for the two most important waveform attributes (bandwidth efficiency and bit error rate performance) are presented. These results will be used by a follow-on study to significantly reduce the number of candidate waveforms, so that all attributes can be more thoroughly evaluated.