FPGA Implementation of a TVWS Up- and Downconverter Using Non-Power-of-Two FFT Modulated Filter Banks

This paper addresses an oversampled filter bank (OSFB) approach to up- and down-convert any or all of the 40 channels in the United Kingdom's TV white space (TVWS). We particularly consider the use of non-power-of-two fast Fourier transforms (FFTs), which provides a greater choice of design parameters over existing OSFB implementations. Using a field-programmable gate array (FPGA) software defined radio (SDR) platform, we compare two different 40-point FFT-based implementations of the system - one fully parallelised, one serialised - with an existing design using a radix-two 64-point FFT in terms of implementation cost and power consumption.