Cooperative Spectrum Detection Algorithm Based on Likelihood Ratio Law for Cognitive Radio Systems

摘要

The cognitive radios must have the capability to determine if a signal from a primary transmitter is locally present in a certain spectrum. This paper proposed a cooperation algorithm for spectrum detection based on likelihood ratio for primary users' detection in multi-user's cognitive radio system, this algorithm has especially considered different channels decline with the state of decaying of the route between primary users and a lot of cognitive users, the single node detection adopts the energy law. According to the likelihood ratio law, the mathematical model is set up, and has simplified relevant parameters rationally, has reduced algorithm complexity.