Efficient Implementation of 64-Point FFT/IFFT for OFDM on FPGA

Orthogonal Frequency Division Multiplexing (OFDM) is a multi-carrier modulation technique which divides the available spectrum into many carriers. OFDM uses the spectrum efficiently compared to FDMA. With the rapid growth of digital wireless communication in recent years, the need for high-speed mobile data transmission has increased. FPGAs have become key components in the implementation of high performance DSP systems. The objective of this paper is to design and efficiently implement FFT and IFFT blocks required for a base band OFDM transmitter and receiver on FPGA hardware. IFFT/ FFT blocks are complex to implement and main blocks of OFDM system i.e. it consumes more resources. So, a efficient technique used here in which FFT/IFFT is implemented in such a way that it consumes very less resources. This module of 64-point FFT and IFFT is designed using VHDL programming language. In this work, a pure VHDL design, integrated with some intellectual property (IP) blocks, is employed to implement an OFDM transmitter and receiver. The proposed design is map and test on Xilinx Virtex 5 FPGA and for simulation, synthesis and implementation XILINX ISE 13.1 software is used.