Deep out-of-band radiation reduction by using joint filterbank and cancellation carriers in cognitive radios

A deep spectrum sculpting is necessary to enable coexistence between a cognitive radio (CR) user and a licensed user which has low dynamic range and is susceptible to interferences. In this paper, we propose to use joint filter-bank based multicarrier system and cancellation carriers to guarantee an almost free interference transmission and keep the quality of services of licensed adjacent bands unchanged. We investigate the performance of the proposed method with different well-known existing methods from viewpoints of the average level of out-of-band power, spectral efficiency, and computational complexity.