Cooperative Spectrum Detection System with Multicarrier BPSK Transmitters and Double-Sampling Rate DMC Receiver

The employment of a double-sampling rate (dsr) at the receiver of the decision-making center (dmc) in a multicarrier cooperative spectrum detection (csd) system is investigated in this paper. the spectrum detection is obtained for a cognitive mobile communication network with a single licensed user (lu) and multiple cognitive users (cus). in the investigated system, each cu performs a local-detection independently; based on the local detection, a single-bit local-decision is taken at each cu. decisions from cus are modulated using a binary phase-shift keying (bpsk) and then transmitted to the dmc over orthogonal subcarriers and under frequency-selective rayleigh fading channels. signals from cus are observed at the dmc receiver and sampled at a rate twice that of the transmitter to gain diversity. the results - verified using matlab plots - show that using the dsr at the dmc receiver reduces the overall sensing errors and removes performance degradation effects due to the timing-offset between the cus transmitters and the dmc receiver. moreover, these improvements are achieved without any degradation in the spectral-efficiency of the system or increase in the complexity of the transmitter at the cu.