Tdd Baseband Communication System Based On Fpga Design And Implementation

With the rapid development of wireless communication technology, a variety ofcommunication standards are widely used presently. So the resource of frequencyspectrum becomes more restricted. People have paid more attention to the mobilewireless communication standards, projects, and systems based on the Time DivisionDuplex(TDD), which has the following features: dispensing with using paird spectrum,ease of implementation and low cost, etc.At present, the3rd generation standards ofwireless mobile communication that spread fast are turning to TDD mode, as well as the4th generation’s which is developed energetically.In China, the wireless mobilecommunicatin mode of TDD mode has been paid a great deal of attention. For example,TD-SCDMA standard with independent intellectual property rights is based on it.This paper establishes a baseband communication system based onTime-Division Duplex mode with Xilinx Virtex-5FPGA.And then finishes thecommunication of120Mbps signals modulated in π/4-QPSK.This system is composedof FPGA,DSP,DAC and ADC. The ADC and DAC complete the conversion betweenanalog signals and digiatal signals.The DSP is made as the network layer,communicating with upper modules. The FPGA will finish most base-band digitalsignal processing of the system.This paper will focus on the base-band digital signalprocessing module in FPGA such as encode and decode.And it finish a interfaceprogram, with it FPGA cound communicate with DSP through EMIF(external memoryinterface).Besides them, the paper also design a module to achieve the synchronizationof communication between two connected devices and control the switchs betweentrassmitter and receiver. After all, the system will be test and the results will beanalysed.The baseband communication system based on the TDD mode of this paper,provides a scheme for the baseband design of the wireless communication system.