Spectral Sculpting of OFDM Signal for Opportunistic Spectrum Access
OFDM机会频谱接入的信号频谱成型方法

In this paper, two novel methods called EAIC (Extended Active Interference Cancellation) and EAIC-H (EAIC-Hybrid) for spectral sculpting of OFDM signal are proposed. In EAIC and EAIC-H, cancellation signals are added to OFDM signal to cancel interference in target spectrum band caused by data tones, so that interference perceived by primary user can be limited. The cancellation signal (EAIC tones) has longer time duration than that of OFDM symbol, which enables a better notching capability than that of most existing methods. Simulation results show that the proposed methods can obtain very deep spectral notches of about 80 dB. Compared with EAIC, EAIC-H provides a better tradeoff between notching performance and SNR degradation for high order modulation.