An unsigned autocorrelation based blind spectrum sensing approach for cognitive radio

Autocorrelation-Based Spectrum Sensing for OFDM Signals over Multipath Fading Channel in Cognitive Radio Systems

“…The proposed spectrum-sensing method is compared with conventional blind spectrum-sensing methods based on unsigned autocorrelation [18] and entropy [17] over the AWGN channel in Figure 13. Shaikh et al [18] considered the OFDM-transmitted signal for energy detection and the unsigned autocorrelation for BPSK digital modulation on the AWGN Detection probability of the proposed, unsigned-autocorrelation-based, entropy-based and energy-based spectrum-sensing methods under BPSK modulation channel, and thus we consider this scenario for comparison here. For the performance comparison, common parameters are used for all the blind methods at a false alarm probability of 0.001.…”

“…The system complexity of the method is high due to the use of automatic gain control (AGC) and an analog-to-digital converter (ADC). However, recently, unsigned autocorrelationbased blind spectrum sensing was proposed, where a band pass filter is used before the autocorrelation calculation [18]. The detection performance of the method is unsatisfactory in severe noise environments.…”

“…We have considered an FFT with a large size for an OFDM-transmitted signal for the performance evaluation of spectrum sensing. In simulations, the proposed method is compared with autocorrelation-based [18], [19], well-known energy-detection-based [14], and entropy-based [17] spectrum-sensing methods for detecting OFDM-transmitted signals. As a result, the proposed method shows a marked performance improvement relative to these methods.…”