Multi-Differential Slightly Frequency-Shifted Reference Ultra-wideband (UWB) Radio

The frequency-shifted reference (FSR) ultra-wideband (UWB) communication scheme has been recently proposed by the authors. The key idea of the FSR-UWB system is to employ a reference signal that is slightly shifted in frequency from the data-bearing signal, and it has been shown that this results in a very simple receiver architecture. In particular, such a scheme obviates the need for the delay element that greatly complicates implementation of the receiver in standard transmitted reference UWB (TR-UWB) systems. In this paper, we propose a multi-differential FSR-UWB system, where multiple data carriers employ a single reference carrier. This modification essential increases the number of (differential) degrees of freedom available for signaling in the system. However, unlike most communication systems that provide such a dimensionality increase, the large ratio between the UWB system bandwidth and the carrier separation allows the multi-differential FSR-UWB to achieve this significant increase in signal space dimensionality over the standard FSR-UWB system with only a negligible increase in bandwidth. After a general performance characterization, applications to parallel data signaling, multidimensional signaling, and narrowband interference cancellation are considered that demonstrate the utility of the proposed scheme.