Receiver controlled medium access in multihop ad hoc networks with multipacket reception

The advent of diversity modulation and signal processing has changed the underlying assumption of the conventional collision model that at most one packet can be received at each node of a network. The use of antenna arrays, code division multiple access (CDMA), and space-time processing with multiuser detection makes multipacket reception (MPR) a more realistic model for the physical layer of future wireless networks. In this paper, a multiple access protocol based on receiver controlled transmissions (RCT) is presented for multihop ad hoc networks with MPR nodes. As a hybrid of scheduled and random access MAC, the RCT protocol is capable of providing high throughput at heavy traffic load and short delay in light traffic. Unlike existing global scheduling techniques, RCT requires only coarse coordination among regions of the ad hoc network, and it scales to networks of arbitrary sizes. Capacity analysis and the application of RCT for Manhattan-type multihop networks are presented where scheduled reception interval and the size of local contention are optimized. Performance analysis and simulations are also presented.