Determination of the threshold solution for an «improved» energy detector in spectrum sensing Rayleigh channel

Background. The classical scheme of an energy detector is widely used as part of spectrum sensing systems. The simplicity of the energy detector implementation and the required minimum of a priori data are its main advantages. The development of these schemes is an «improved» energy detector, which has been actively considered in the. The development of these schemes, which do not require complicating the algorithm of operation or additional data, is an «improved» energy detector, which brings it closer in characteristics to coherent types of detectors, which has been actively considered in the last decade. Aim. The article discusses the problem of determining most important parameter-the threshold for detecting a licensed user by the criterion of the minimum total probability of errors of the 1st and 2nd kind, which can be easily generalized to the criterion of the minimum average risk, it is more suitable in many practical situations for detecting spectrum occupancy situations for cognitive users. Threshold optimization is considered using the example of a well-known and well-studied Rayleigh fading channel. Methods. The threshold value is determined based on the solution of the differential equation for the sum of error probabilities. Results. The solution in the form of a normalized threshold is a function of one variable: the average signal-to-noise ratio. Conclusion. The results obtained make it possible to correlate the characteristics with those of a classical energy detector, as well as a CFAR detector that meets the specified technical requirements for the false alarm level. It also confirms the importance for any type of energy detector of quality indicators for estimating the noise power in a channel, such as the range of possible values of this power and the range of reliable sensing results.