| 摘要 |
A method (10) is provided of setting up a call over a multiple bit-rate transmission channel between a central module (25) and a remote module (22). The channel comprises at least one first transmission channel (401) having a primary bit rate and at least one second transmission channel (402) having a secondary bit rate. Each of said first and second transmission channels is a two-way channel comprising a first transmission half-channel (43, 45) in one direction and a second transmission half-channel (44, 48) in another direction. The method comprises the following steps: setting up a call on the primary transmission channel, scanning for a signal indicating a secondary bit-rate requirement, and if a signal indicating a secondary bit rate requirement is detected, bit-rate switching from said first transmission channel (401) to the second transmission channel (402). The switching is undertaken at different points in time for said first transmission half-channel (43, 45) and said second transmission half channel (44, 48).
|
