SSB and DSB Enabled Hybrid Waveforms for the Space-Ground Link System

The spectrum sharing problems call for the solutions to compress the uplink space-ground link system (SGLS) spectrum and minimize the interference to the neighboring bandwidth. In this paper, single sideband (SSB) and double-sideband (DSB) enabled hybrid waveforms are proposed to reduce the bandwidth and improve the spectrum efficiency of SGLS. A hybrid modulation (HM) structure is designed to generate the double sideband command signals and single sideband telemetry and ranging signals. At the receiver side, a Costas loop-based carrier synchronization supports the demodulation of hybrid waveforms. Numerical results show the implementation losses associated with the hybrid modulation-demodulation processes are negligible. The hybrid waveforms cut the required bandwidth in half, while giving essentially the same bit error rate (BER) performance as traditional DSB waveforms.