Multiplex communications – Communication over free space – Repeater
Reexamination Certificate
1997-06-12
2001-03-27
Nguyen, Chau (Department: 2663)
Multiplex communications
Communication over free space
Repeater
C455S427000
Reexamination Certificate
active
06208625
ABSTRACT:
FIELD OF THE INVENTION
This invention relates generally to satellite communications and, more particularly, to routing delay-sensitive and non delay-sensitive data through satellites.
BACKGROUND OF THE INVENTION
Prior-art satellite communications networks use either low-earth orbit (LEO), medium-earth orbit (MEO), or geosynchronous orbit (GEO) satellites to transfer data from a data source to a destination. Such data can include, for example, delay-sensitive data such as voice data communicated during a phone conversation. Voice data is particularly delay-sensitive because long, delay-imposed pauses during oral communications can make communication quality poor. Data requiring transfer through a network also can include non delay-sensitive data such as, for example, system overhead data including: call setup information; TT&C data (telemetry, tracking, and control); routing information; billing information; and short messages (e.g., pages).
LEO satellites are better suited than GEO satellites for communication of delay-sensitive data. Because GEO satellites are located at a substantially greater distance than LEO satellites from the earth-based equipment with which they communicate, significantly longer signal propagation delays are inherent in communications between GEO satellites and earth-based equipment. Because of the delay issues associated with GEO satellites, many prior-art satellite communication networks designed for voice communications use LEO satellites to communicate delay-sensitive data traffic.
The call-handling capacity of a LEO satellite network is inversely proportional to the amount of system overhead data which must be routed through the network. Because system overhead data is routed through the LEO satellites in prior-art systems, the satellites cannot provide as many traffic channels as they would be able to in the absence of such system overhead data.
Because high-capacity systems are highly desirable, what is needed is a method and apparatus which increases the traffic carrying capacity of a satellite network by reducing the effect of transferring system overhead data throughout a system.
REFERENCES:
patent: 5218467 (1993-06-01), Ross et al.
patent: 5408237 (1995-04-01), Patterson et al.
patent: 5467345 (1995-11-01), Cutler, Jr. et al.
patent: 5490087 (1996-02-01), Redden et al.
patent: 5887257 (1999-03-01), Olds
patent: 5906337 (1999-05-01), Williams et al.
patent: 0767547 (1996-09-01), None
Article entitled “Personal Communications Via Low Earth Orbit Satellite Communication Networks”, Richard A. Raines and Nathaniel J. Davis, IV (Nov. 1995).
Book entitled “Mobile Communication Satellites” T. Logdson (1995), pp. 129-147, XP002078784.
Krutz Michael William
Vatt Gregory Barton
Zancho William Frank
Bogacz Frank J.
Klekotka James E.
Lee Chiho Andrew
Motorola Inc.
Nguyen Chau
LandOfFree
Method and apparatus for increasing call-handling capacity... 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 and apparatus for increasing call-handling capacity..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for increasing call-handling capacity... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2490387