METHOD FOR PROVIDING RING BACK TONE SERVICE BY USING MULTIMEDIA AUDIO CODEC IN WCDMA SYSTEM

摘要

A method for supplying an RBT(Ring Back Tone) by using a multimedia audio CODEC(Coder Decoder) in a WCDMA(Wideband Code Division Multiple Access) system is provided to enable a receiving MS(Mobile Station) to supply an RBT sound source to a sending MS by using a preset multimedia audio CODEC, so that the sending MS can reproduce the RBT sound source by using the stored multimedia audio CODEC. A sending MS sends a call proceeding message to an origination MSC(Mobile Switching Center)(S202). An HLR(Home Location Register) includes information on a receiving-side MS and routing information on a termination MSC in the first SRI(Send Routing Information) response message, and then transmits the response message to the origination MSC(S204). The origination MSC sends the first IAM(Initial Address Message) to the termination MSC(S206). The termination MSC performs a paging procedure to the receiving MS(S210), and transmits the second IAM message to a CRBT(Caller RBT) server(S212). The CRBT server transmits the first ACM(Address Complete Message) to the termination MSC(S214). The termination MSC sends a setup message to the receiving MS, and the receiving MS sends a call confirm message to the termination MSC(S216). The origination MSC sends the first alerting message to the sending MS(S220), and an RBT sound source using a multimedia audio CODEC is transmitted to the sending MS(S222).