Improved autocorrelation demodulation receivers based on multiple-symbol detection for UWB communications

The autocorrelation demodulation (ACD) has potential for use in medium-range low-cost UWB communications, however, its weak performance is a bottle neck. To improve ACD's performance, it is proposed to combine the multiple-symbol detection with ACD to form a multiple-symbol-based ACD receiver. In contrast to ordinary ACD scheme that uses symbol-by-symbol decision, the proposed structure uses block-based multiple-symbol joint decision. Performance of the new scheme is evaluated analytically for arbitrary block sizes employing Gaussian approximation approach. The accuracy of the method is verified by computer simulation. The evaluation shows that the proposed scheme offers several dB improvement in performances with only a moderate increase in complexity.