| 摘要 |
A wireless telecommunication device conducts base station pages at large intervals, such as 30 seconds, rather than the more conventional 0.5 to 4 seconds. The network processes calls placed to that telecommunication device in accordance with an SMS (Short Messaging Service) type protocol rather than a conventional voice call protocol. Particularly, the network sends an SMS to the telephone indicating that a third party is calling (hereinafter termed a "pre-call SMS"). The pre-call SMS indicates the telephone number of the third party. The user of the telephone may call the third party back. In accordance with this protocol, the need to page at very short intervals so as to permit a telephone call to be established in "real-time" is eliminated. Therefore, the paging interval can be increased substantially, thereby substantially prolonging battery charge lifetime of the telephone. In accordance with another aspect of the invention, when a cellular telephone sends a pre-call SMS, it temporarily decreases its paging interval to a more conventional interval such as 0.5 seconds for a predetermined period of time (e.g., 1-5 minutes) after placing a call so that, if the called party returns the call, the calling party will receive the return call in real-time and be able to answer the incoming call and establish a voice call. |
