FPGA Implementation of Polyphase Digital Down Converter for WiMAX Systems

ABSTRACT This paper briefs the implementation of a reconfigurable digital down converter (DDC) on a field-programmablegate array (FPGA) development board to be used in worldwide interoperability for microwave access (WiMAX) applications. The proposed polyphase design includes a parallel number of coordinate rotation digital computer (CORDIC) processors and low-passfinite impulse response (FIR) filters. Furthermore, the single rate FIR filter works with complex data input using canonical implementation. This strategy reduces multiplications and computational complexity. Additionally, the sample rate factor can be dynamically reconfigured to support multistandard DDC architectures. The mathematical expressions of the proposed design are briefly described. Comparison results indicate that the proposed design saves the hardware resources to achieve a cost-effectivesolution for software-definedradio standards. The simulation and experimental results are used to verify the correctness and feasibility of the polyphase DDC structure.