Wireless networks are rapidly developing into heterogeneous networks that can adopt a variety of base station sizes and types. In addition to macro cells, these networks can also use micro cells, urban cells, micro cells, and even nano cells. These different kinds of base stations must meet different needs. For macro cell and cloud ran architecture, baseband and return processing are separated from RF using CPRI / obsai over fiber. Small cells have a higher level of integration, and return, baseband and and RF processing are usually integrated on a single platform. Based on throughput, serial bandwidth, power consumption level and the number of users, the requirements of small cells are quite different; In some cases, it can be implemented on a single device.