Spatial Research Of Spectrum Detection Design In Cognitive Radio

The thesis comes from the 863 Program: the research of cognitive radio technique. Cognitive radio was invented to solve the problem of the scarcity of the radio electromagnetic spectrum, the fundamental thought of which is to improve the utilization percent of spectral resource. Cognitive radio is defined as an intelligent wireless communication system that is aware of its environment and uses the methodology of understanding-by-building to learn from the environment and adapt its internal states by making corresponding changes in certain operating parameters in real time, in order to promote the efficient use of the spectrum and revive the lack of spectral resource.The thesis researches the spatial research of spectral detection design in cognitive radio. The improved method defines the interference temperature in arbitrarily location, and it calculates the interference temperature in arbitrarily location by estimating the information of interfering sources and gains the distribution of the interference temperature in the interested area. Then the distribution of the interference temperature is compared with the interference temperature limit, and spectrum holes are gotten. The information of interfering sources needs to be estimated in improved method. Here, the information of interfering sources contains the number of interfering sources, the location of interfering sources and the transmit power. According to the known information of interfering sources, the thesis discusses how to estimate the unknown information of interfering sources on three scenarios. Among which some methods of array signal processing is used. Moreover, the thesis carries on the simulation analysis and comparison.