On Routing and Rate Control Strategies in Wireless Multi-Hop Random Access Networks

In this paper, we investigate in the context of multi- hop ad hoc wireless networks the impact of combined multi-rate and packet forwarding and routing operations on the throughput performance of the system. Our models and analysis results reveal key performance and design options involving the cross- layer operation of such networks. We carry out mathematical analysis in computing the transport throughput performance of the network under the use of different modulation/coding schemes (MCSs) that operate at different data rates. The medium access control (MAC) scheme is assumed to be based on a random access (pure ALOHA type) protocol. In configuring the parameters of the employed MCS, we use the Information theoretic (Shannon´s) capacity formula, as well as settings that are based on IEEE 802.11 implementations. The results provide characterizations of the network´s (end to end) throughput performance in terms of the underlying physical (and certain MAC) layer parameters in combination with the setting of the link and network layer involved packet forwarding range and routing scheme configuration. Our models provide important guidelines for the design of such rate adaptation algorithms and for the selection of the involved parameters and schemes at the physical, link and network layers.