Capacity in Wireless Systems with Random Access and Delay Constraints

It can be desirable in some wireless systems, including mobile ad hoc networks (MANETs), to use a random access multiple access scheme. In this case, the uncoordinated arrival of packets at a node that receives transmissions from two or more other nodes results in contention. This contention is particularly high at a node that aggregates traffic transmitted from a number of nodes. When delay sensitive information is carried, the physical layer packet loss probability must be low; this requirement, in conjunction with the multiple access contention, severely limits the receive capacity of a node that aggregates traffic from multiple transmitting nodes. Design tradeoffs to increase the capacity are explored, which are applicable to a broad class of packet arrival processes and are applied to a wide range of the number of transmitting nodes.