Implementation of orthogonal frequency division multiplexing modem using radix-N pipeline fast fourier transform (FFT) processor

In this paper, a new Radix-N pipeline fast Fourier transform (FFT) processor for the implementation of IEEE 802.11a baseband orthogonal frequency division multiplexing (OFDM) modem for wireless local area network (WLAN) is proposed. The newly proposed scheme has a simple control structure and multiplication block is designed based on canonic signed digit (CSD) with N/4 twiddle factors, which enables both hardware complexity and power consumption to be reduced as about less 33% and 66% respectively than the conventional Radix-4 pipeline and Radix-2 pipeline structures. In order to verify the real time operation, the IEEE802.11a baseband OFDM test-bed with the newly proposed Radix-N pipeline FFT processor is implemented using field programmable gate array (FPGA) devices.