Telecommunications – Radiotelephone system – Zoned or cellular telephone system
Reexamination Certificate
1999-03-05
2001-01-16
Eisenzopf, Reinhard J. (Department: 2682)
Telecommunications
Radiotelephone system
Zoned or cellular telephone system
C455S515000, C455S161300, C455S185100
Reexamination Certificate
active
06175733
ABSTRACT:
TECHNICAL FIELD
This invention relates in general to wireless communication services, and more particularly to restoring communication service to a communication device upon experiencing an interruption of communication service.
BACKGROUND OF THE INVENTION
Wireless communication systems are in widespread use in virtually all metropolitan areas of the world. In particular, communication systems using a geographic frequency reuse scheme, more commonly known as cellular communications systems, are the most popular. As a communication device moves from one serving cell to another, communication service hands off from one cell to the next in corresponding fashion.
One drawback with these communication systems is that communication service is sometimes lost or interrupted. Primarily this occurs when the signal from the serving cell is lost, and no other serving cells can be detected. There are a number of common scenarios where this occurs. One occurs when the communication device is camped on a serving cell, meaning no hand off to another cell is imminent, and the communication device enters an area that is shielded from serving cell's signal, such as in elevator, or upon entering a tunnel. Another scenario occurs when the communication device travels from an area covered by a serving cell into zone where there is no serving coverage, often referred to as a “dead zone.”
The conventional method of restoring service involves scanning the serving cell frequency that was in use when the interruption occurred, and the frequencies of the neighbor cells of the serving cell in an attempt to locate a suitable carrier. This method is fine for minor interruptions, but it fails to account for situations where the communication device has moved to a new area during the interruption. Therefore, there is a need for a method of restoring communication service to a communication device that takes into consideration the possibility that the communication device may be in a new region when it becomes possible to restore communication service.
REFERENCES:
patent: 5262769 (1993-11-01), Holmes
patent: 5457816 (1995-10-01), Koyama
patent: 5497508 (1996-03-01), George
patent: 5499386 (1996-03-01), Karlson
patent: 5517677 (1996-05-01), Moon
patent: 5711001 (1998-01-01), Bussan et al.
patent: 5751772 (1998-05-01), Mannette et al.
patent: 5937351 (1999-08-01), Seekins et al.
Barker, Jr. Charles R.
Parikh Saumil
Seekins David S.
Eisenzopf Reinhard J.
Garrett Scott M.
Kincaid Lester G.
Motorola Inc.
LandOfFree
Method for recovering communication service does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method for recovering communication service, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for recovering communication service will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2552729