摘要 |
<p>In a synchronous fixed frame boundary system with variable data rates, a transmitter (10) inserts into a current frame an indication of the data rate of the next frame. As a station modem (18) assembles a current frame for encoding, the station modem (18) inserts a rate indication for the subsequent frame in accordance with information from a vocoder (22) and CPU (20) of the appropriate data rate for the subsquent frame. On the receiver (30) side, rather than decoding multiple times to determine the appropriate data rate for every frame, the receiving station modem (38) discovers the rate of each frame subsequent to the first frame.</p> |