Estimating pointing loss for user terminals of a satellite communications system

• US 8,077,629 B2
• Filed: 01/28/2009
• Issued: 12/13/2011
• Est. Priority Date: 01/29/2008
• Status: Active Grant

• Current Assignee: ViaSat Incorporated
• Original Assignee: ViaSat Incorporated
• Inventors: Miller, Mark J.
• Primary Examiner(s): MARCELO, MELVIN C
• Application Number:
  US12/361,417
• Publication Number:
  US 20090190491A1
• Time in Patent Office: 1,049 Days
• Field of Search: 370/252, 370/316
• US Class Current: 370/252
• CPC Class Codes: H04B 17/40 of relay systems
• CPC Class Codes: H04B 7/185 Space-based or airborne stations; Stations for satellite systemsH04B7/204 takes precedence
• CPC Class Codes: H04B 7/18513 Transmission in a satellite or space-based system
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

Techniques are provided herein for monitoring the performance of a satellite communications system, including techniques for determining the pointing loss of a plurality of user terminals in the satellite communications system using the isotropic radiated power (EIRP) of the satellite.

Claims

1. A method for estimating the pointing loss for a plurality of user terminals of a satellite communications system, the method comprising:

calculating a terminal specific constant for each user terminal in the plurality of user terminals, the plurality of user terminals having a similar effective isotropic radiated power (EIRP) of the satellite;

identifying a terminal in the plurality of user terminals having a maximum terminal specific constant, the terminal associated with the maximum terminal specific constant having a minimum pointing loss in the plurality of terminals;

calculating the EIRP of the satellite using the terminal specific constant for the terminal having the maximum terminal specific constant; and

estimating the pointing loss for each of the plurality of user terminals, except for the terminal having the maximum terminal specific constant, using the EIRP of the satellite.

2. The method of claim 1 wherein the terminal specific constant is a function of a symbol rate of the link, Bolzmann'"'"'s constant, path loss and a measured signal to noise ratio.

3. The method of claim 1 wherein calculating the terminal specific constant further comprises solving for the following equation:

4. The method of claim 1 wherein calculating the EIRP of the satellite using an ideal gain-to-noise-temperature (G/T) and the terminal specific constant for the terminal having the maximum terminal specific constant further comprises:

calculating the value of EIRP of the satellite for using the following equation;

5. The method of claim 1 wherein estimating the pointing loss for each of the plurality of user terminals using the EIRP of the satellite further comprises:

estimating the value of pointing loss for each user terminal using the following equation;