High performance OFDM communication system

Abstract

OFDM is used in high speed communication systems like LTE. It works by dividing the available spectrum in orthogonal overlapping sub-carriers or by dividing a higher data rate link into low data rate links. Thus OFDM, using orthogonal sub-carriers, achieve high data rates at low bandwidth. However, OFDM is highly sensitive to carrier frequency interferences. And, if carrier position is affected by noise, orthogonality property is lost, which in turn severely affects system performance. The main aim of the project is to apply carrier synchronization for OFDM. Our goal will be to maximize the system performance by applying carrier synchronization on the receiver side. The prototype for the project was initially developed on Xilinx Virtex 5 FPGA using VHDL. After that the project was shifted on NI-USRP 2922 for simulation and real time data transmission. The OFDM model is first simulated on NI LabVIEW Communications System Design Suite and the real time communication is then communicated between two NIUSRPs 2922 for demonstration purposes. The CFO elimination and channel estimation is done on the receiver side.