Michael Chambers

US Patent:

62723588, Aug 7, 2001

Filed:

Jun 4, 1998

Appl. No.:

9/090362

Inventors:

Kenneth Wayne Brent - Miami FL
Michael Dwayne Chambers - Plainfield IL
Anne Yin-Fee Lee - Naperville IL
Chinmei Chen Lee - Woodbridge IL

Assignee:

Lucent Technologies Inc. - Murray Hill NJ

International Classification:

H04B 138
H04B 1404
H04M 100
H04Q 720
H04L 1266

US Classification:

455560

Abstract:

Apparatus for performing a smooth by-pass of extra Vocoders in a mobile station to mobile station connection. Vocoders are used in mobile stations using digital signals to communicate with base stations. When the vocoded signals are to be transmitted over the public switched telephone network, they are normally converted into the kinds of signals such as 64 Kb per second pulse code modulation (PCM), used in the public switched network. In accordance with one preferred embodiment of this invention, when a connection is made between two mobile units, the connection is made via a separate asynchronous transfer mode (ATM) network. Arrangements are also available to switch between the ATM network and Vocoders connected to the public switched telephone network when it is necessary to transmit a PCM signal to a land based station, or other equipment. Advantageously, this arrangement allows switches between by-pass mode and non/by-pass mode to be made seamlessly without requiring a synchronous operation of that switch in the two switching systems involved in a connection, and therefore, further improves the voice quality during Vocoder by-pass because there is no disruption of the voice path when the by-pass mode is activated or deactivated.