Direct spectrum division transmission for highly efficient satellite communications

This paper proposes a new concept in direct spectrum division transmission. The transmitter divides the single carrier modulated signal into multiple "sub-spectra" in the frequency domain and arranges each sub-spectrum so as to more fully utilize the unused frequency resources. In the receiver, the divided sub-spectra are combined in the frequency domain and demodulated. By editing the divided spectrum in the frequency domain, the total bandwidth occupied by the multiple "sub-spectra" is less than that of the modulated signal. The proposed technique allows the unused frequency resources scattered across the bands to be better utilized. In addition, it suppresses the peak to average power ratio (PAPR) compared to conventional multi-carrier transmission techniques. Simulation results show that the proposed technique makes the bit error rate degradation negligible and reduces the PAPR by 1.5dB.