Abstract
In this thesis, we consider the transport capacity of a Gaussian multiple access channel (MAC) in a mobile communications scenario in which all the nodes are allowed to be mobile. The transport capacity was first proposed by Gupta and Kumar as a figure of merit about how effectively a wireless network operates, and is given by the summation of the ratereward products (the products of the data rates and the associated rewards for the successful transmission of the data) over all transmitter-receiver pairs. Most existing works on the maximal transport capacity are for a fixed wireless communications network in which all the nodes are located at fixed positions. However, it has been shown by Grossglauser and Tse that if mobility could be exploited to increase the maximal transport capacity. Therefore, in this thesis we investigate the maximal transport capacity of Gaussian MACs in the scenario that all the nodes are allowed to be mobile, and study the optimal positions of the mobile nodes that achieve the largest possible maximum transport capacity.