Research And Optimization Of Collaborative Spectrum Sensing Technology At Cognitive Networks

With the development of wireless communication technology, it is obviously for the lack of spectrum resources and the inefficiency of static spectrum allocation policy. How to improve the spectrum utilization has become a core issues in wireless communication. Dr. Mitola proposed the concept of cognitive radio in1999to solve the problem of the shortage of spectrum resources. Soon, cognitive radio became a hot research field in wireless communications. Spectrum sensing is a very important research topic in cognitive radio. This paper studies the cooperative spectrum sensing technology on cognitive networks.Firstly, this paper does some research on the key technologies of cognitive radio, especially on various technologies for spectrum sensing.Secondly, this paper proposes a passive collaborative detection scheme based on sensing compensation, focusing on analyzing the advantages and disadvantages between the technology of single point detection and the technology of collaborative spectrum detection, this paper does a lot research on the detection performance and energy loss for both passive detection and active detection. Simulation results show that, both in AWGN channel and Rayleigh fading channel, the detection performance of proposed scheme is superior to the traditional passive detection program and its energy loss is much lower than active detection scheme, at the same time, the delay of collaborative detection is shorten and the spectrum detection performance is improved.Lastly, this paper also does some research on data fusion scheme in the proposed scheme, and proposes an asynchronous fusion strategy to match the proposed detection scheme. Find the law between the data fusion cycle and the detection performance by researching the effect to asynchronous fusion strategy from various environmental factors. At last, proposes an adaptive strategy for data fusion through practical model simulation.