Abstract: A system and method for aiding emergency service providers in locating an incapacitated individual by use of a wireless communications device. The invention has two major modes of operation based upon whether the line of communication between the handset and call destination is open or closed. If the connection between the handset and the call destination is open, the audible beacon periodically generates a preselected tone through the built-in speaker of the telephone. The audible beacon may be initiated from the call destination location, after there has been an established link between the telephone and the call destination, whether the connection is open or closed. Once the audible beacon is initiated, the stored volume settings of the handset are replaced by the volume settings of the audible beacon system and the preselected tone of a telephone ringer or a beep. The tone remains activated until manually turned off.

Abstract: The present invention is a novel and improved technique for performing coding with particular application to turbo, or iterative, coding techniques. In accordance with one embodiment of the invention, interleaving is performed by generating the address of a memory using a PN state generator. Data is written into a memory in sequential order, and then read out using addresses specified by the PN state generator. To deinterleave, the interleaved data is written into a memory using addresses specified by the PN state generator, and then read out in sequential order. A set of PN state generators that provide excellent coding performance is provided.