Multi-antenna pre-equalization for single-carrier/TDD system

Severe frequency-selective fading, encountered in broadband wireless mobile communication, significantly degrades the single-carrier (SC) signal transmission performance. Multi-antenna frequency-domain pre-equalization (called pre-FDE) is presented for spread-spectrum single-carrier (SC) systems. At the transmitter, pre-FDE, with a transmit power constraint, is applied for each transmit antenna; no equalization function is necessary at the receiver. It is shown, by computer simulation, that pre-FDE transmission can provide significant improvement in the bit error rate (BER) performance in a frequency-selective Rayleigh fading channel and can achieve a BER performance close to that attainable by FDE reception. For a mobile communication system, the pre-FDE transmission for the downlink (base-to-mobile) and FDE reception for the uplink (mobile-to-base) can be implemented at a base station. This allows a simple implementation of mobile transceivers.