563305 is referenced by 34 patents.

A push-to-talk communication device to participate in a group communication net 100 is claimed. The group communication net 100 comprises a controller 104 to manage the group communication net 100 and interface with the push-to-talk communication devices 108, 112 and 116. A processor converts information signals into packet data suitable for transmission over a distributed network. The processor may also have identification information, and updates its identification information when its current identification information has or is about to change. The processor then transmits its new identification information to the controller 104. The push-to-talk devices 108, 112 and 116 also comprise a transmitter to transmit packet data through a first channel to the controller. A receiver receives packet data through a second channel from the controller. The push-to-talk devices 108, 112 and 116 also comprise a user activated mechanism to activate the transmitter when a user of the communication device wishes to transmit packet data to the controller.

Method and apparatus for participating in group communication services in an existing communication system
Application Number
Publication Number
Application Date
April 10, 2001
Publication Date
November 21, 2003
Rosen Eric
Crockett Douglas M
Maggenti Mark
Qualcomm Incorporated
H04L 012/00