Fully interconnected spot beam satellite communication system

• US 4,813,036 A
• Filed: 11/27/1985
• Issued: 03/14/1989
• Est. Priority Date: 11/27/1985
• Status: Expired due to Term

• Current Assignee: National Express Incorporated
• Original Assignee: National Express Incorporated
• Inventors: Whitehead, Clay T.
• Primary Examiner(s): Olms, Douglas W.
• Application Number:
  US06/802,990
• Time in Patent Office: 1,203 Days
• Field of Search: 370/57, 370/69.1, 370/104, 455/12, 455/13
• US Class Current: 370/325
• CPC Class Codes: H04B 7/2041 Spot beam multiple access

Abstract

A communication signal can be routed from any location in a spot beam satellite system to any other location within the spot beam system by simply choosing the proper carrier frequency for the uplink to the satellite. The spot beams are fully interconnected without any need for active switching within the satellite. An uplink signal received by one or more satellites in a particular orbit location may be routed, depending on its frequency, to any downlink spot beam. A network control center located on the ground in one of the spot beam coverage areas receives signalling requests from all the spot beam coverage areas and assigns frequencies so that the desired routing can be established. All of this is accomplished without any signal demodulation or active switching of circuit paths in the satellite.

Claims

1. A communication system for providing communication routes between a plurality of communication points, comprising

frequency-selective routing array means having a plurality of electronic paths wherein each electronic path is distinct from each other electronic path and said frequency-selective routing array means is adapted to receive electronic signals and transmit electronic signals and is adapted to be located within an airborne satellite, and

network control means located on the ground and physically apart form said frequency-selective routing array means and adapted to communicate with said communication points and adapted to select carrier frequencies for communications between said communication points and through said frequency-selective routing array means and wherein the frequency of said selected carrier frequencies determines which electronic path is used.

2. A communication system as in claim 1 wherein

said satellite is adapted to use spot beams and said frequency-selective routing array means is adapted to communicate with said communication points using spot beams and wherein said network control means is adapted to communicate with said frequency-selective routing array means using spot beams.

3. A communication system as in claim 2 wherein each said electronic path of said frequency-selective routing array means corresponds to a different carrier frequency and wherein said network control means is adapted to select a particular carrier frequency to be used by each communication point for communications between communication points through said frequency-selective routing array means.

4. A spot beam satellite communication system for providing communication routes between a plurality of ground stations comprising

frequency-selective routing array means having a plurality of electronic paths wherein each electronic path is distinct from each other electronic path and said frequency-selective routing array means is adapted to receive and transmit electronic signals and to be located within an airborne satellite adapted to use spot beams,

network control means physically apart from said frequency-selective routing array means and located on the ground, and adapted to communicate with said ground stations and to select carrier frequencies for communications with said ground stations and through said frequency-selective routing array means, and wherein the frequency of said selected carrier frequency determines which electronic path is used, and

spot beam antenna means located on said satellite and adapted to transmit electronic signals as said spot beams and to receive electronic signals from said ground stations.

5. A spot beam satellite communication system for providing communication routes between a plurality of ground stations comprising

satellite means adapted to be airborne,

frequency-selective routing array means having a plurality of electronic paths wherein each electronic path is distinct from each other electronic path and said frequency-selective routing array means is adapted to receive and transmit electronic signals and to be located within said satellite,

ground stations adapted to transmit signals and to receive signals from said satellite means,

network control means physically apart from said frequency-selective routing array means and located on the ground, and adapted to communicate with sad ground stations and to select carrier frequencies for communications between said ground stations and through said frequency-selective routing array means, and wherein the frequency of said selected carrier frequency determines which electronic path is used, and

spot beam antenna means located on said satellite and adapted to transmit electronic signals as spot beams and to receive electronic signals from said ground stations.

6. A system as in claim 5 including

fractional filter means wherein a fractional filter is in each said electronic path.