Study on a new ringing method of EPON

This paper first present a new ringing method which using time tag of relativity according existing ringing method.Then,the new ringing method is compared with the old one.The time delay of sign when transmitting in the fiber is changing when environment factor changed.So,in order to limiting the error of the upstream data at some scope,ringing must be carried out periodically.The minimum ringing cycle of the new one is double of the old one's.Besides,compare with the old ringing method,the new one is achieved more easily and applied more widely.At the last,the two scenarios are compared with experiment,and the result of the experiment is accord with the result of theory analysis.