OFDM vs. single-carrier : a multi-antenna comparison
2004 IEEE International conference on acoustics, speech and signal processing, VOL IV, proceedings: audio and electroacoustics signal processing for communications
IEEE International Conference on Acoustics, Speech, and Signal, Processing, MAY 17-21, 2004, Montreal, CANADA
, p. 753-756
University of Antwerp
There is an ongoing discussion in the broadband wireless world about the respective benefits of Orthogonal-Frequency-Division-Multiplexing (OFDM) and Single-Carrier with Frequency-Domain equalization (SC-FD). SC-FD allows for more relaxed front-end requirements, of which the power amplifier efficiency is very important for battery-driven terminals. OFDM, on the other hand, can yield improved performance at low complexity. Both schemes have extensions to multiple antennas to enhance the spectral efficiency and/or the link reliability. Moreover, both schemes have non-linear versions using Decision-Feedback Equalization (DFE) to further improve performance of the linear equalizers. In this paper, we compare these high-performance OFDM and SC-FD schemes using multiple-antennas and DFE, while also accounting for the power amplifier efficiency. To make a realistic comparison, we also consider most important digital imperfections such as channel and noise estimation, transmit and receive filtering, clipping and quantization as well as link layer impact. Our analysis shows that for frequency-selective channels the relative performance impact of the power amplifier is negligible compared to the frequency diversity impact. The higher frequency diversity exploitation of SC-FD allows it to transmit more efficiently than OFDM in most cases. Therefore, SC-FD is a suitable candidate for broadband wireless communication, especially for battery-powered up-link transmission.