ADAPTIVE DELAY REDUCTION OUTBOUND
Original Publication Date: 1997-Mar-01
Included in the Prior Art Database: 2002-May-16
Within the iDEN system, outbound audio data is transferred at lhkbps. Voice samples are VSELP encoded, HDLC encoded, and are then transmitted from the Transcoder within the Base Site Controller (BSC) to the Base Radio (BR). The packets are then sent out over the air to the mobile on an assigned timeslot. An algorithm in the iDEN system called Just in Time Audio (JITA) is implemented to reduce outbound audio delay. JITA works by having the BR Host make estimates of how much sooner pack- ets arrive at the BR than they are needed. This rep- resents excess delay in the system. The BR Host sends the Transcoder timing estimates to change the VSELP encode window so that packets are sent down to the BR just in time to go out over the air.