Ultra-Wideband Relay Communication Systems

Graduation date: 2016Access restricted to the OSU Community, at author's request, from December 31, 2015 - December 31, 2017Impulse-radio ultra-wide-band (IR-UWB) signaling is a promising technique\ud for high-speed, short-range relay communications networks. Depending on how\ud the relay node retransmits the signal, there are two main relay schemes: conventional\ud one-directional (one-way) relay model, and bi-directional (two-way) relay\ud model. In bi-directional relay communications, wireless network coding (WNC),\ud also called physical-layer network coding (PNC), could be applied to overcome\ud the spectral efficiency limitation of the conventional one-way relay.\ud \ud In the first part of this work, we propose asynchronous, differential, and\ud bidirectional decode and forward (ADBDF) and asynchronous, differential, and\ud bidirectional denoise and forward (ADBDNF) UWB relay methods, where the\ud relay node (RN) does not need to be synchronized with the end nodes (ENs). The\ud proposed schemes are attractive for networks in which stringent/complicated\ud synchronization between the RN and the ENs may not be feasible.\ud \ud The second part of this work focuses on UWB channel classification. We propose\ud a 2-dimensional (2-D) LOS/NLOS classification scheme that uses skewness of the channel impulse/pulse response. The proposed channel classification decreases\ud the complexity of existing channel classification methods and can be used\ud in a variety of areas such as localization, relay communications, and cooperative\ud communications.\ud \ud The final part of this work deals with compressive sensing (CS) algorithms\ud that employ sub-Nyquist sampling for UWB communications. We develop coarse\ud graining (CG) for the proposed CS sub-Nyquist sampling technique, which leads\ud to: (1) reduced sampling rate at the receiver, and hence reduced use of analog-to-digital\ud converters (ADCs) resources; and (2) low-complexity channel estimation