HANDOVER BETWEEN ATC AND SATELLITE COMPONENT OF AN INTEGRATED MSS/ATC SYSTEM

• US 20130281010A1
• Filed: 05/03/2013
• Published: 10/24/2013
• Est. Priority Date: 06/05/2006
• Status: Active Grant

• Current Assignee: Globalstar Incorporated
• Original Assignee: Globalstar Incorporated
• Inventors: Monte, Paul A., Gallagher, Vijaya, Shah, Brinda T.
• Granted Patent: US 9,294,187 B2
• Time in Patent Office: Days
• US Class Current: 455/13.4
• CPC Class Codes: H04B 7/18513 Transmission in a satellite or space-based system
• CPC Class Codes: H04B 7/18563 Arrangements for interconnecting multiple systems data switching networks H04L12/00
• CPC Class Codes: H04B 7/19 Earth-synchronous stations

Abstract

A communications system comprising a first transceiver and a second transceiver, which system employs a device that measures power over a frequency band from sources other than those monitoring downlink radiation received at a radio terminal from the satellite, and a controller that receives these power measurements to determine on which frequency channel within a band a transmitter is to transmit.

Claims

1. A communication system comprising:

at least a first transceiver including at least a first receiver and at least a first transmitter;

at least a second transceiver including at least a second receiver and at least a second transmitter;

a device that measures power over a frequency band from sources other than those monitoring downlink radiation received at a radio terminal from a satellite;

a controller that receives and processes said measurements to determine in which frequency channel within the band a transmitter is to transmit; and

wherein signal to noise ratio is measured instead of power.

2. The communication system as defined in claim 1 wherein said at least second transceiver transmits the said frequency channel to said at least first transceiver to determine frequency for said first transceiver to transmit to said second transceiver.

3. A method for handing over wireless communications in a satellite communications system, the satellite communications system comprising at least one satellite that is configured to wirelessly communicate with at least one radio terminal in a satellite coverage area over a satellite frequency band and an ancillary terrestrial component that is configured to wirelessly communicate with at least one radio terminal in the satellite coverage area over at least some of the satellite frequency band, to thereby terrestrially reuse at least some of the satellite frequency band, the handover method comprising:

handing over wireless communications with a radio terminal from the ancillary terrestrial component to the satellite component by determining which frequencies are more suitable or receive less interference in a band by measuring the interference levels at each frequency at a gateway.

5. The method as defined in claim 3 wherein handing over comprises handing over wireless communications with the radio terminal from the ancillary terrestrial component to the satellite component when the radio terminal transmit power exceeds a threshold, an aggregate radio terminal interference exceeds a limit and the satellite component signal quality exceeds a threshold, even though the radio terminal is able to wirelessly communicate with the ancillary terrestrial component.

6. The method as defined in claim 3 wherein handing over comprises handing over wireless communications with the radio terminal from the ancillary terrestrial component to the satellite component if the radio terminal transmit power exceeds a threshold, the satellite component signal quality exceeds a threshold and the radio terminal is at least a predetermined distance away from the ancillary terrestrial component when the radio terminal is able to wirelessly communicate with the ancillary terrestrial component.

4. A method for handing over wireless communications in a satellite communications system, the satellite communications system comprising at least one satellite that is configured to wirelessly communicate with at least one radio terminal in a satellite coverage area over a satellite frequency band and an ancillary terrestrial component that is configured to wirelessly communicate with at least one said radio terminal in the satellite coverage area over at least some of the satellite frequency band, to thereby terrestrially reuse at least some of the satellite frequency band, the handover method comprising:

handing over wireless communications with a radio terminal from the satellite component to the ancillary terrestrial component by determining which frequencies are more suitable or receive less interference in a band by measuring the interference levels at each frequency at a gateway.

7. A communication system comprising:

at least a first transceiver including at least a first receiver and at least a first transmitter;

at least a second transceiver including at least a second receiver arid at least a second transmitter;

said at least second transceiver measures the power over a frequency band;

a controller in said at least second transceiver that receives said measurements to determine which frequency channel within a band the at least first said transmitter is to transmit on; and

said at least second transmitter transmits the said frequency channel information to said at least first transceiver.

8. The communication system as defined in claim 7 wherein said at least second transceiver communicates with a plurality of at least a first set of transceivers.

9. The communication system as defined in claim 7 wherein the at least second transceiver measures the interference or power from each transceiver in the at least first set of transceivers.