Deepen spectrum notch of CR signals with Partial Response System

Partial response system (PRS) is introduced to OFDM technology to deepen spectrum notch when some subcarriers are turned off. By this, controllable interference which can be removed in the receiver without enhancing system complexity, is introduced to the cognitive radio (CR) signals. It can change spectrum shape of subcarriers of OFDM signals and deepen the spectrum notch when turning off some subcarriers. Therefore, this method can lower the interference between primary users and secondary ones in CR systems. Some simulation results are shown in this paper to approve the performance of this method.