| 摘要 |
A method of communicating data between a base station and a plurality of terminal devices comprises transmitting data from the base station to the plurality of terminal devices in a multicast transmission and transmitting response signals from the terminal devices to the base station to indicate (acknowledge) whether or not the respective terminal devices have successfully received the multicast transmission. The use of a multicast transmission provides an efficient mechanism for communicating the same data to a plurality of terminal device, for example as might be desired in a machine-type communication network. In combination with this, the use of individual response signals, such as ACK / NACK signalling, from the terminal devices allows the base station, or other entity, such as a machine-type communications server, to track which terminal devices have indicated successful receipt of the multicast transmission, and to instigate an appropriate re-transmission protocol accordingly. Suitable for devices requiring a reduced bandwidth, such a smart meters, operating on virtual carriers of a fourth generation 4G, Long Term Evolution, LTE, network, wherein the multicast transmissions and acknowledgements are made using downlink and uplink transmission resources on frequencies selected from with a frequency bandwidth which is smaller than the total frequency bandwidth available. |
