Siegfried F Rehwinkel

US Patent:

56895496, Nov 18, 1997

Filed:

Dec 1, 1994

Appl. No.:

8/347745

Inventors:

Guido Bertocci - Freehold NJ
William J. Nealon - Neptune City NJ
Siegfried F. Rehwinkel - Middletown NJ
Walter Tomkoski - Jamesburg NJ
Hon-Chi Yu - Aberdeen NJ

Assignee:

Lucent Technologies Inc. - Murray Hill NJ

International Classification:

H04Q 720

US Classification:

379 61

Abstract:

A cordless telephone system includes an arrangement wherein multiple portable units operate with a common base unit using the same security code without conflict or confusion. When a portable unit attempts to establish a radio link with the base unit, for example, this originating portable unit generates a random number which is retained by this unit and also transmitted to the base unit. This random number is substituted for the common stored security code, then shared by the base unit and all of the portable units, for creating a temporary unique security code that is known only to the base unit and the originating portable unit. Interference from other portable units attempting to gain access to the base unit while the originating portable unit is actively communicating with the base unit is thereby advantageously prevented.

US Patent:

60290714, Feb 22, 2000

Filed:

Dec 1, 1994

Appl. No.:

8/347744

Inventors:

Guido Bertocci - Freehold NJ
William J. Nealon - Neptune City NJ
Siegfried F. Rehwinkel - Middletown NJ
Walter Tomkoski - Jamesburg NJ
Hon-Chi Yu - Aberdeen NJ

Assignee:

Lucent Technologies Inc. - Murray Hill NJ

International Classification:

H04Q 738

US Classification:

455463

Abstract:

A cordless telephone system achieves synchronism for each one of multiple portable units to the same communication channel for communicating with a common base unit. The cordless system uses a dual channel process to allow both the freedom to dynamically change channels as needed to avoid interference while simultaneously providing a capability to resynchronize any portable unit with the base unit on a selected active channel. This is achieved through the use of a fixed service channel and an active channel which changes as needed. If a channel change is made during a call, after the call is completed, the base unit returns to the previous active channel and broadcasts a message to the multiple portable units indicative of the new active channel. Also, any portable unit that attempts to communicate with the base unit on the wrong channel and fails to get a response will transmit a message on the fixed service channel requesting the current active channel from the base unit. Responsive to this request, the base unit provides information indicative of the active channel over the service channel.