Abstract:

With the increase of primary user’s (PU) transmission performance, the cognitive user’s (CU) performance will be decreased rapidly in cognitive wireless networks (CWNs). A new opportunistic cooperative transmission scheme based on spectrum sensing in CWNs is proposed. Then, a closedform expression of average bit error ratio (BER) for the proposed scheme is presented over Rayleigh fading channels. Numerical simulations are conducted to compare the proposed scheme with the traditional noncooperative transmission, showing the merits of the proposed scheme in terms of BER, and the transmission performance of CU in CWNs are improved without interfering with the regular transmissions of  PU.