Method and device for accurately pointing a satellite earth station antenna

• US 20060181455A1
• Filed: 02/15/2005
• Published: 08/17/2006
• Est. Priority Date: 02/15/2005
• Status: Active Grant

• Current Assignee: ViaSat Incorporated
• Original Assignee: WildBlue Communications, Inc. (ViaSat Incorporated)
• Inventors: Hudson, Erwin C., Martin, Remberto L.
• Granted Patent: US 7,289,062 B2
• Time in Patent Office: Days
• US Class Current: 342/359
• CPC Class Codes: H01Q 1/1257 using the received signal strength
• CPC Class Codes: H01Q 3/08 for varying two co-ordinates of the orientation

Abstract

A device for measuring the received signal strength at an Earth station antenna has the capability to provide an accurate pointing indication when the frequency bands and other key characteristics of the satellite signals are not uniform over the coverage area. The device has an input port, a plurality of passive or active signal filters, a filter selector and an output port. The device may further contain a signal amplifier with automatic or manual gain control. A plurality of filters is provided which may be coupled singularly or in combination between the input port and the output port. Each filter or combination of filters is associated with a particular geographic area and capable of allowing the satellite signal assigned to that geographic area to pass while attenuating or blocking other signals, noise and interference. The filter selector is used to connect the appropriate filter or combination of filters between the input port and the output port. A signal amplifier with manual or automatic gain control may be included to provide an output signal at the desired signal level. The output port may be connected to a power measuring unit, antenna pointing meter or other similar device to provide an accurate antenna pointing indication in the particular geographic area corresponding to the filter or filter combination selected.

Claims

1. A method of accurately pointing a satellite Earth station antenna by:

selecting a signal filter based on the geographic location at which the user Earth station antenna is to be installed;

wherein the selected filter has bandpass characteristics selected based on parameters of a satellite signal associated with that geographic location such that the satellite signal associated with that location is allowed to pass while effectively blocking other signals, noise and interference not associated with the satellite signal provided at that location;

configuring a signal meter to measure satellite signals received by a user Earth station antenna through the selected filter;

receiving from the user Earth station antenna a plurality of signals, noise and interference across a plurality of frequency bands at an input to the selected filter;

isolating, using the selected filter, the satellite signal associated with that geographic location;

measuring a signal strength of the isolated satellite signal with the signal meter; and

positioning the user Earth station antenna to maximize the signal strength or other related measure of signal quality as indicated by the signal meter.

2. The method of claim 1, wherein configuring the signal meter comprises attaching the selected filter to at least one of the signal meter and a signal amplifier device that is coupled to the signal meter.

3. The method of claim 1, wherein the signal meter is coupled to a housing, the housing comprising:

an input port which may be attached to an output of a user Earth station antenna;

a plurality of filters with bandpass characteristics based on parameters of the satellite signal associated with that geographic location, such that the satellite signal associated with that location is allowed to pass while effectively blocking other signals, noise and interference not associated with the satellite signal provided in that location;

a filter selector operable to insert a particular filter into the signal path between the user Earth station antenna and the signal meter;

an output port operable to be coupled to the signal meter;

wherein selecting the filter comprises selecting one of a plurality of filters and wherein configuring the signal meter comprises configuring the filter selector so that the satellite signal of interest received at the input port is transmitted through the selected filter to the signal meter.

4. The method of claim 1, wherein the Earth station antenna is located in one of a plurality of satellite antenna beams formed by a plurality of satellite antennas, such that the signals transmitted by the satellite may differ in at least one of frequency band, bandwidth, and spectral shape across the plurality of beams.

5. The method of claim 1, wherein the satellite operates within at least one of Ku-band and Ka-band and provides at least one of two-way audio, two-way data and two-way video service using antenna beam frequency reuse in a plurality of beams formed by the satellite antennas.

6. The method of claim 1, wherein the satellite operates within at least one of Ku-band and Ka-band and provides one-way communication using antenna beam frequency reuse in a plurality of beams formed by the satellite antennas.

7. The method of claim 1, wherein the Earth station antennas are located in one or more beams where less than the full complement of satellite transmitters is activated.

8. The method of claim 1, wherein the signal is transmitted by an airborne communications device operating above the surface of the Earth in a manner to allow for line-of sight transmissions.

9. The method of claim 1, wherein the signal is transmitted by a communications device fixed in a manner to allow for line-of sight transmissions.

10. A device for accurately pointing a user Earth station antenna comprising of:

an input port which may be attached to an output of a user Earth station antenna;

a plurality of signal filters which may be coupled to the input port, each filter associated with a particular geographic area and operable to allow a signal received in a frequency band assigned to that geographic area to pass while effectively blocking signals, noise and interference in other frequency bands;

a filter selector operable to insert a selected filter into the signal path between the Earth station antenna and a signal meter;

an output port operable to be coupled to a signal meter and to provide the filtered signal to the signal meter.

11. The device of claim 10, further comprising a signal amplifier in the signal path between the user Earth station antenna and the signal meter operable to amplify the signal to a level sufficient to allow the signal meter to measure the filtered satellite signal.

12. The device of claim 10, wherein the signal amplifier is operable to receive power through the signal path received through at least one of the input port and the output port.

13. The device of claim 10, further comprising the signal meter, wherein the signal meter is operable to measure the signal strength of the filtered satellite signal;

and a housing, the housing enclosing at least a portion of each of the filter selector, the signal amplifier, the amplifier output port, and the signal meter.

14. The device of claim 10, wherein the filter input port comprises a threaded portion operable to couple to a coaxial cable through which signals are transmitted to the filter input port.

15. The device of claim 10, further comprising:

a microwave receiver coupled to the filter input port and operable to receive signals transmitted at a frequency greater than approximately one (1) Gigahertz (GHz); and

a housing enclosing at least a portion of each of the selector, the signal amplifier, the filter input port, and the microwave receiver.

16. The device of claim 10, wherein:

the device is operable to operate at an intermediate frequency of approximately 1-2 GHz;

the input port and the output port comprise type-F coaxial connectors;

the plurality of filters comprises eight filters;

the filter selector comprises a mechanical switch with eight positions;

each filter is further operable to allow a signal received within a unique frequency band to pass;

each of the unique frequency bands comprises a range of approximately sixty (60) Megahertz (MHz);

the device has an amplifier with a fixed gain of approximately ten (10) decibels (dB); and

the device is powered by a direct current (DC) voltage present at the input port.

17. A device for accurately pointing a satellite Earth station antenna comprising:

a plurality of attachable signal filters, wherein each signal filter is operable to be attached to a signal meter and is associated with a particular geographic area and operable to allow a satellite signal received in the frequency band assigned to that geographic area to pass while effectively blocking signals in other frequency bands; and

a signal amplifier, the signal amplifier comprising an amplifier input port which may be selectively attached to a selected signal filter and an amplifier output port operable to be coupled to a signal meter, and wherein the signal amplifier is operable to amplify an output of the selected signal filter to a level sufficient to be measured by the signal meter.

18. The device of claim 17, wherein:

each of the signal filters comprises a threaded portion;

the amplifier input and output ports comprise a threaded portion;

the signal meter input comprises a threaded portion; and

the threaded portion of each of the signal filters is operable to be connected to either the threaded portion of the amplifier input port or the threaded portion of the signal meter input port.

19. The device of claim 17, wherein the device further comprises:

the signal meter;

a housing comprising an input port, an output port, and a socket operable to couple to the selected signal filter, wherein the housing encloses at least a portion of the signal meter and at least a portion of the selected signal filter;

the input port of the housing operable to couple to the satellite Earth station antenna;

the output port of the housing operable to couple to the signal meter; and

the selected signal meter operable to couple to at least one of the output port and the input port of the housing.

20. The device of claim 17, wherein:

the device operates at an intermediate frequency of approximately 1-2 GHz;

each signal filter comprises a filter input port that includes a type-F coaxial connectors and a filter output port that includes a type-F coaxial connectors;

the amplifier input port includes a type-F coaxial connector and the amplifier output port includes a type-F coaxial connectors;

the signal meter further comprises a meter input port that includes a type-F coaxial connector;

the plurality of signal filters comprises eight signal filters;

each signal filter is further operable to allow a signal received within a unique frequency band to pass;

each of the unique frequency bands comprises a range of approximately sixty (60) Megahertz (MHz);

the signal amplifier has a fixed gain of approximately ten (10) decibels (dB); and

the signal amplifier is powered a direct current (DC) voltage present on at least one of the amplifier input port and the amplifier output port.

21. The device of claim 17, wherein two or more of the signal filters are operable to be attached in combination to at least one of the signal amplifier and the signal meter.