Efficiency of energy detection for spectrum sensing in a Poisson field of interferers

Spectrum sensing is arguably the most important task expected of a cognitive radio. An effective spectrum sensing algorithm enables the cognitive radio to transmit without causing harmful interference to the licensed user. However, in a multi-user environment, the aggregate interference to the sensing node may adversely affect its sensing performance. In this paper, we investigate the performance of a sensing node in the presence of unlicensed user interference in a non-cooperating secondary network. We model the interference as a Poisson point process in the two dimensional plane and characterize the effect of various factors such as the sensing time and density of interferers on the overall performance of the spectrum sensor. To this end, novel expressions have been developed to calculate the false alarm and detection probabilities of an energy detection sensor in an interference environment. The results obtained were verified using Monte Carlo simulation techniques.