Minimum allowable spectrum sensing time for DVB-T signals

Spectrum sensing has been identified as a key enabling functionality to ensure that cognitive radios would not interfere with the primary user, which are the Digital Video Broadcasting - Terrestrial (DVB-T) receivers. This paper deals with spectrum sensing techniques used for efficient utilization of the limited spectrum resources. The most used technique is the energy detection (ED) as it is the simplest one for real time implementation and performs well for high SNR. This paper is an extension for our previous work of the Improved Periodogram-Based (IPB) method [11]. IPB method introduces an enhanced ED technique, which led to better performance in low SNR conditions. The proposed IPB method is based on the Welch-Bartlett Method used for power spectral density (PSD) estimation in frequency domain, to make the detection more robust in a noisy environment. Simulation results are performed on DVB-T signals in additive white Gaussian noise (AWGN) context. These show that the proposed detector performs much better than the conventional energy detector. We also examine the minimum allowable spectrum sensing time and obtain the minimum sensing time that satisfies the optimum FFT resolution under the probability of a specified false alarm constraint.