A real-time software implementation of an OFDM modem suitable for software defined radios

A digital signal processing technology that implements a baseband OFDM modem suitable for software defined radios requires a design platform, which is highly flexible and reconfigurable. In this paper a real-time OFDM system including interleaving and forward error correction algorithms is implemented based on a DSP platform. The software reconfigurable system is developed on a Texas Instruments TMS320C6201 Evaluation Module. Software modules representing discrete system blocks are created and sequentially called upon as needed. Coding efficiency is employed with the use of look-up-tables and cyclic shift registers. Memory management ensures maximal use of on chip memory for critical instructions. Cycle counts are used to calculate maximum bit-rates. Using these results, estimations for rates achievable by a higher performance processor is made.