Micro-Coded Programmable Solution for a Class of OFDM Applications

Abstract

In modern communications systems, there is a growing need for programmability, yet cost pressures push towards full ASIC solutions. Our paper describes a common platform capable of implementing different OFDM-based computational requirements. This engine can compute Radix-2, and Radix-4 DFT and IDFT, Pre- twiddling and post twiddling, complex gain scaling and shift scaling. A novel technique for automatic overflow protection will be described, which reduces internal quantization effects. The complexity is much lower than that of a general purpose DSP and the gate count is comparable to full hardware implementation, yet the engine provides performance comparable to full hardware and programmability through the execution of microcode.