05311570 is referenced by 87 patents and cites 16 patents.

A communications switching system such as a PBX, central office switch and the like, responds to an incoming call to a called party by signaling a paging device as well as some other communications device having communications capability different from that of the paging device. In the disclosed embodiment, which pertains to a private branch exchange (PBX), this other communications device is one which provides two-way voice communications. Advantageously, the paging device may also be provided with the capability of signalling the communications system that the called party will shortly answer the call via a communications device possessing two-way voice communications. Upon receipt of this pager-transmitted signal, the communications system, if desired, can be provided with the ability to provide an announcement to the calling party of the called party's intent to answer the call. Once the called party reaches any voice communications device connected to the system, the incoming call is redirected to that device upon the called party providing a predetermined identification to the communications system.

Title
Integration of wireless paging in a communication system
Application Number
7/699084
Publication Number
5311570
Application Date
May 10, 1991
Publication Date
May 10, 1994
Inventor
Lawrence J Haas
Broomfield
CO, US
Gary J Grimes
Thornton
CO, US
Agent
David R Padnes
Assignee
AT&T Bell Laboratories
NJ, US
IPC
H04Q 7/04
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