Effects of Hard Decision on the Detection of Preambles for UWB Non-Coherent Communications

In this paper, the ability of well-known energy detection (ED) and transmitted reference (TR) receivers for ultra wideband (UWB) low data rate (LDR) communications to detect synchronization sequences is studied. We focus especially on the degradation caused if, with an objective of low complexity, a hard decision is done on every chip of the sequence. The probability of missed detection and false alarm are calculated for both receivers in a synchronization scheme compliant with the preambles proposed in the IEEE 802.15.4a draft standard. The equations show that the two receivers have the same performance in terms of receiver operating characteristics (ROC). Then, the effect of hard decision is analytically considered and simulations are performed in order to find a possible trade off between performance and complexity