| 摘要 |
An alarm device is arranged to transmit an alarm signal indicative of an alarm condition being met. The alarm device accesses a record of a list of cellular networks available for communication with the device. The record includes information identifying each of the networks, and a measure of the reliability of communication over each network. The alarm device selects a network with which to establish a communication link based on the measure of the reliability of communication over the network, and attempts to establish a communications link with the selected network. The measure of reliability of communication over each network may be based on signal strength, such as the cell signal quality; signal to noise ratio; number of cells within effective range of the device; and bit error rate. The network with the highest measure of reliability may be selected by the device. |
