| 摘要 |
The circuit includes a modem with a circuit (1) providing a first signal (CD) indicating the load on the network according to a comparison between the received signal (RAI) and a predetermined threshold value. A device switches the modem into a transmission or reception mode. A digital circuit (10) provides a second signal (CD') indicating the load on the network. This is determined by identifying a predetermined sequence of data in each transmission frame before a data message. A further circuit (5,6,8) authorises switching of the modem into its transmission mode when the load signals (CD,CD') both indicate the absence of a transmission. |
