Interference temperature estimation based on the detection of directions of arrival of multiple sources

To improve the frequency spectrum utilization of secondary users,a novel interference temperature estimation approach based on direction-of-arrival(DOA)is presented in this paper. By deriving the angles between the interference signals and primary user signals,the actual interference signal sub-value in the same direction of the primary user communication is estimated. The new method outperforms the conventional algorithm by improving signal-to-interference ration(SIR)and reducing the interference temperature estimation value,which can match the real radio propagation environment. Practical measurement and simulation results show the effectiveness to improve the frequency spectrum utilization of secondary users.