Non-interfering utilization of non-geostationary satellite frequency band for geostationary satellite communication

• US 8,068,827 B2
• Filed: 10/09/2008
• Issued: 11/29/2011
• Est. Priority Date: 10/09/2007
• Status: Active Grant

• Current Assignee: ViaSat Incorporated
• Original Assignee: ViaSat Incorporated
• Inventors: Tchorz, John C., Miller, Mark J.
• Primary Examiner(s): Rego; Dominic E
• Application Number:
  US12/248,714
• Publication Number:
  US 20090093213A1
• Time in Patent Office: 1,146 Days
• Field of Search: 455/3.03, 455/12.1, 455/13.2, 455/98, 455/427, 455/404.1, 455/404.2, 455/456.1
• US Class Current: 455/427
• CPC Class Codes: H04B 7/185 Space-based or airborne stations; Stations for satellite systemsH04B7/204 takes precedence
• CPC Class Codes: H04B 7/18515 Transmission equipment in satellites or space-based relays
• CPC Class Codes: H04B 7/18528 Satellite systems for providing two-way communications service to a network of fixed stations, i.e. fixed satellite service or very small aperture terminal [VSAT] system
• CPC Class Codes: H04B 7/19 Earth-synchronous stations
• CPC Class Codes: H04B 7/195 Non-synchronous stations

Abstract

A method, satellite and system utilizes non-geostationary satellite orbit (NGSO) frequency spectrum in geostationary satellite orbit (GSO) satellite communication in a non-interfering manner. A ground station transmits signals to a GSO satellite using a GSO frequency band and an extended frequency spectrum including the an NGSO frequency band whenever a noninterference situation exists, i.e., when an NGSO satellite is not in-line between the earth terminal and the GSO satellite or when the NGSO satellite is not utilizing the NGSO band of interest. A command module is provided to instruct the ground station to transmit signals to the GSO satellite using the GSO frequency band and the extended frequency spectrum.

Claims

1. A geostationary orbit (GSO) satellite communication system comprising:

at least one ground station configured to transmit signals to a GSO satellite using a GSO frequency band, the ground station being further configured to transmit signals to the GSO satellite using an extended frequency spectrum, the extended frequency spectrum including the GSO frequency band and a non-geostationary orbit (NGSO) frequency band;

a command module configured to (i) identify whether an NGSO satellite presents an interference situation between the GSO satellite and the ground station, (ii) instruct the ground station to transmit signals to the GSO satellite using only the GSO frequency band if an interference situation is identified, and (iii) instruct the ground station

to transmit signals to the GSO satellite using the extended frequency spectrum if no interference situation is identified.

2. The system of claim 1, the interference situation being identified to exist only if the NGSO satellite is operating on the NGSO frequency band and is disposed between the ground station and the GSO satellite such that the NGSO satellite is substantially in-line between the ground station and the GSO satellite.

3. The system of claim 1, the command module being further operative to cause the ground station to transmit signals to the GSO satellite using the extended frequency spectrum continuously whenever the NGSO satellite is not operating in the NGSO frequency spectrum.

4. The system of claim 1 wherein the extended frequency spectrum comprises an uplink GSO frequency band portion with an uplink NGSO frequency band portion and a downlink GSO frequency band portion with a downlink NGSO frequency band portion.

5. The system of claim 1, the command module comprising a data processing unit coupled to a memory unit configured to store orbital ephemeris data of the NGSO satellite.

6. The system of claim 5, the memory unit being configured to be modified with updated orbital ephemeris data.

7. A geostationary orbit (GSO), satellite comprising:

a receiver configured to receive from one or more ground stations signals in a GSO frequency band and in an extended frequency spectrum, the extended frequency spectrum including the GSO frequency band and a non-geostationary orbit (NGSO) frequency band;

circuitry configured to establish an activated frequency mode to activate one of a GSO frequency band mode and an extended frequency spectrum mode based on information indicating a presence or an absence of an interference situation with an NGSO satellite system; and

a transmitter configured to transmit in one of the GSO frequency band and in the NGSO frequency spectrum based on the activated frequency spectrum mode.

8. The satellite of claim 7 further comprising:

a low-noise amplifier operative to amplify the transmitted signals and output an amplified signal;

a frequency mixer having a first input adapted to receive the amplified signal, a second input coupled to a local oscillator, and an output having a plurality of frequency products including a downlink extended frequency spectrum, the downlink extended frequency spectrum comprising a downlink GSO frequency band and a downlink NGSO frequency band;

a splitter having an input coupled to the mixer output, a first splitter output and a second splitter output;

a switch having a first input, a second input, and an output;

a first bandpass filter having a first bandpass input coupled to the first splitter output and a first bandpass output coupled to the first input of the switch;

a second bandpass filter having a second bandpass input coupled to the second splitter output and a second output coupled to the second input of the switch;

the first bandpass filter being configured to pass the GSO frequency band;

the second bandpass filter being configured to pass the extended frequency spectrum; and

the output of the switch being selectively coupled to either the first switch input or the second switch input.

9. The satellite of claim 7 further comprising:

a control device configured to decode instructions from a command module to couple the output of the switch to the first input or the second input according to the decoded instructions, the control module providing the information indicating presence or absence of an interference situation with an NGSO satellite system.

10. A method for operating a geostationary (GSO) satellite comprising:

receiving at a command module information indicating a presence or an absence of an interference situation between the GSO satellite and a non-geostationary orbit (NGSO) satellite; and

based on the received information, causing the activating in the GSO satellite and a ground station one of a GSO frequency spectrum mode and an extended frequency spectrum mode, the extended frequency spectrum mode providing communication between a ground station and the GSO satellite in a GSO frequency band and a non-geostationary (NGSO) frequency band

causing the transmitting of signals between the GSO satellite and the ground station using the GSO frequency band or the extended frequency spectrum based on the frequency spectrum mode.

11. The method of claim 10, the extended frequency spectrum mode being caused to operate substantially continuously when the NGSO satellite does not operate in the NGSO frequency band.

12. The method of claim 10 comprising using stored orbital ephemeris data of the NGSO satellite system to determine presence or absence of an interference situation with the NGSO satellite system.

13. The method of claim 12, further comprising receiving and utilizing updated orbital ephemeris data.

14. The method of claim 10, the command module being located at one location on earth.

15. The method of claim 10, the command module being distributed among a plurality of locations on earth.