Analytical Techniques for Performance Evaluation of Fountain-Coded File Distribution in Packet Radio Networks

Convenient analytical techniques are developed for use in preliminary design of systems and protocols for the delivery of fountain-coded files from a source node to a destination node with the assistance of a relay node. Each node has a half-duplex packet radio, and the time-varying disturbance on each link is represented by a lumpable finite-state Markov chain. The analytical techniques include the use of first passage times and recurrence times in the derivation of an exact expression for the completion time of file transfer over a radio link and the application of results on Markov-correlated Bernoulli trials to obtain exact expressions for completion times of relay-aided file transfer in wireless networks. In the development of analytical techniques, we employ capacity-achieving channel codes and ideal fountain codes; however, we present simulation results for packet radios that employ practical channel codes and for which the fountain code is a standard systematic raptor code.