In the process of the continuous development of the Internet of things, new and old technologies of wireless network appear alternately. Network compatibility issues become the core of technology breakthrough. This paper studies on the heterogeneous wireless network, and optimizes the network with cooperative relay technology. It studies on the heterogeneous wireless network selection algorithm; puts forward the utility function parameters setting method based on fuzzy inference system, to solve the problem of function parameters index for different mobile terminals, implementing relay positioning and power allocation from oneway and two-way relay transmission systems respectively.