Channel-access and routing protocols to utilize multiple heterogeneous channels for ad hoc networks.

摘要

In this thesis, we consider a multi-channel ad hoc network employing frequency-agile radios that utilize direct-sequence spread-spectrum signaling. Two of the key distributed protocols for this type of network control channel access and routing. The channel-access protocol is responsible for controlling access to the channels available to the terminals in the network, and the routing protocol determines how packets are forwarded among the terminals in the network. To achieve reliable and efficient network performance, these protocols should cooperate with one another and take advantage of the multiple channels available to the network.;In this thesis, we investigate a number of channel-access strategies for selecting a channel as well as various channel metrics to be used with routing. For our channel-access protocol, one channel is designated the control channel and is used to reserve access to one of the traffic channels. The channel-access protocol selects the traffic channel for a data packet transmission by examining the characteristics of the different traffic channels. New channel metrics are proposed to characterize the channels, and the metric values are used to assign a link resistance value for a link. Least-resistance routing utilizes the link resistances to calculate routes. The performance of the channel metrics for the routing protocol and the channel-access strategies are examined with a discrete-event simulation. From our investigations, we show that a jointly designed protocol that coordinates the channel-access strategies with the channel metrics results in network performance that is better than traditional channel-access and minimum-hop routing protocols.