摘要 |
A mobile communications system comprising a first network 2 operable with a first communication protocol, a second network 3 operable with a second communication protocol and a portable communication device 10 operable with the first and the second communication protocols. The first communication protocol results in a lower power consumption by the device whilst in a standby status than the second communication protocol. The device is arranged to default to the first protocol whenever the device enters a standby status. The device may also be arranged to default to the protocol which uses less power in an active status whenever the device enters an active status. |