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US 2002/0058477 A1Published application
Return link design for PSD limited mobile satellite communication systems
OwnerMichael de La Chapelleinventor
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OwnerMichael de La Chapelleinventor
Estimating the term…
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.
A method for managing radio frequency (RF) transmissions from an RF system of at least one mobile platform operating within a predetermined coverage region to a space-based transponder orbiting within said coverage region, in a manner to maintain a signal-to-noise ratio (Eb/No) of said RF transmissions within a predetermined range, the method comprising the steps of:
A method for managing radio frequency (RF) transmissions from an RF system of at least one mobile platform operating within a predetermined coverage region to a space-based transponder orbiting within said coverage region, in a manner to maintain a signal-to-noise ratio (Eb/No) of said RF transmissions within a predetermined range, the method comprising the steps of:
A method of determining a power spectral density (PSD) of an RF signal from a mobile platform having an RF transmitter/receiver directed at a space-based transponder, said method comprising the steps of:
Dependencies are inferred from the claim text.