Signal Power Summation Using Satellite Transponders Having Orthogonal Polarizations
AssigneeRaysat Broadcasting Corp.
InventorsIlan Barak, Danny Spirtus
Life of this patent
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Abstract
A method for communication includes transmitting first and second copies of a signal toward first and second satellite transponders, respectively, so as to cause the first and second satellite transponders to transmit respective first and second downlink signals with mutually-orthogonal linear polarizations toward a coverage region. A correction is applied to at least one of the first and second copies before transmitting the first and second copies. The correction is selected so as to remove a frequency offset between the first and second downlink signals and cause the first and second downlink signals to have a constant phase offset in at least some of the coverage region.
Claims26
A method for communication, comprising:
- transmitting first and second copies of a signal toward first and second satellite transponders, respectively, so as to cause the first and second satellite transponders to transmit respective first and second downlink signals with mutually-orthogonal linear polarizations toward a coverage region;
- and
- before transmitting the first and second copies, applying to at least one of the first and second copies a correction, which is selected so as to remove a frequency offset between the first and second downlink signals and cause the first and second downlink signals to have a constant phase offset in at least some of the coverage region.
A communication apparatus, comprising:
- an antenna;
- and
- a calibration receiver, which is located in a coverage region of a satellite that includes first and second satellite transponders, and which is configured to receive using the antenna first and second downlink signals having mutually-orthogonal linear polarizations that are transmitted respectively by the first and second satellite transponders in response to first and second copies of a signal that were transmitted respectively toward the first and second satellite transponders by an uplink transmitter, and to cause the uplink transmitter to apply to at least one of the first and second copies a correction, which is selected based on the received first and second downlink signals so as to remove a frequency offset between the first and second downlink signals and cause the first and second downlink signals to have a constant phase offset in at least some of the coverage region.
A communication system, comprising:
- an uplink transmitter, which is configured to transmit first and second copies of a signal toward first and second satellite transponders, respectively, so as to cause the first and second satellite transponders to transmit respective first and second downlink signals with mutually-orthogonal linear polarizations toward a coverage region;
- a calibration receiver, which is configured to receive the first and second downlink signals and to cause the uplink transmitter to apply to at least one of the first and second copies a correction, which is selected based on the received first and second downlink signals so as to remove a frequency offset between the first and second downlink signals and cause the first and second downlink signals to have a constant phase offset in at least some of the coverage region;
- and
- at least one receiver, which is configured to receive a combined signal, generated by a combination of the first and second downlink signals, using a linearly-polarized antenna.
Dependencies are inferred from the claim text.