The technology of the relay can improve the coverage and the spectrum utilization in broadband access system used on the business of the broadcast TV.Meanwhile
routing is a key part in the study of relay technology.A multi-path routing algorithm is proved in this work.The algorithm includes route discovery
route maintenance
route manage and the mechanism of the relay selection.It can adapt to the change of the network and select the extract relay.The simulation shows that the algorithm can improve the performance of the network in the throughout and time delay
with saving the source of system bandwidth and traffic balance.