Title:
PSD制限下における移動衛星通信システム用リターンリンク設計
Document Type and Number:
Japanese Patent JP4753528
Kind Code:
B2
Abstract:
A system and method for managing access to a satellite-based transponder by a plurality of aircraft each having a mobile radio frequency (RF) system. The system employs a ground-based network operations center ("NOC") having a central control system for managing access to the satellite-based transponder so that the aggregate power spectral density (PSD) of the RF signals of all the mobile systems does not exceed, at any time, limits established by regulatory agencies to prevent interference between satellite systems. This is accomplished by accurately estimating the PSD of each mobile terminal at the NOC using a reverse calculation method to determine mobile terminal EIRP and then using antenna models to project the EIRP on to the GEO arc. Accurate knowledge of the mobile terminal location and attitude is acquired through periodic reports sent from the mobile terminal to the NOC. The invention employs a dual loop return link power control system whereby the receive Eb/No from the aircraft is measured at the ground station and power control commands are sent back to the aircraft to maintain the receive Eb/No within a tight control range above the threshold Eb/No value. The second control loop on the mobile terminal maintains the EIRP at the commanded levels during rapid changes in attitude.
Inventors:
De la chapel, michael
O'Brien, Kevin M
O'Brien, Kevin M
Application Number:
JP2002531644A
Publication Date:
August 24, 2011
Filing Date:
August 23, 2001
Export Citation:
Assignee:
The Boeing Company
International Classes:
H04B7/19; H04B7/26; H04B7/185; H04W84/06
Domestic Patent References:
| JPH11127097A | 1999-05-11 |
Foreign References:
| US5734962A | 1998-03-31 | |||
| WO1997001101A1 | 1997-01-09 | |||
| WO1998045962A1 | 1998-10-15 | |||
| US5463656A | 1995-10-31 |
Attorney, Agent or Firm:
Sonoda Yoshitaka
Kobayashi Yoshinori
Kobayashi Yoshinori