Thesis (PhD)--University of South Australia, 2006 The ever increasing demand for wireless services using mobile cellular communication technology has lead to intensive efforts by researchers to determine the information theoretic limitations of these systems. Toward this end, numerous cellular models have been formulated and analyzed using information theoretic principles to succinctly identify the impact of system constraints and design parameters on performance. One such model that captures the essence of the uplink of a cellular channel is the Gaussian cellular multiple access channel (GCMAC), which is the focus of this dissertation.