| 摘要 |
A D-AMPS+ cellular communications air interface is presented wherein a packet data control channel and packet data traffic channel is supported in addition to the conventional digital control channel and digital traffic channel. In particular, the packet data control channel and packet data traffic channel support multiple modulation level operation (high versus low). Procedures are provided for mobile station selection, as well as re-selection, of either the high or low-level modulation for the packet channels. Procedures are further provided for facilitating a fall-forward to the high-level modulation packet data control channel, or a fall-backward to the low-level modulation packet data control channel with respect to both uplink and downlink packet data communications. |
