Fixed- versus floating-point implementation of MIMO-OFDM detector

In this paper, we investigate the opportunities offered by floating-point arithmetics in enabling an assembly and intrinsics free high-level language based development. We compare the characteristics of floating- and fixed-point arithmetics by simulating a MIMO-OFDM soft output detector in a 3G LTE link level simulator. The hardware complexity and energy dissipation are analyzed by implementing three programmable processors supporting 32- and 12-bit floating-point and 16-bit fixed-point arithmetics. The processors are based on the transport triggered architecture (TTA) that has a very low programmability overhead. The analysis shows that at the same goodput rate a floating-point implementation can achieve a lower gate count and better power efficiency than a fixed-point design.