System and method for canceling co-channel interference on-board a satellite
View Patent ↗Provided are systems and methods for minimizing co-channel interference on-board a satellite. An up-link signal received by the satellite is post-compensated, where the up-link signal includes a desired signal transmitted by a first transmitter and an interfering signal transmitted by a second transmitter. The post-compensating includes identifying the interfering signal based on post-compensation parameters. In addition, a down-link signal to be transmitted from the satellite to a receiver is pre-compensated. The pre-compensation process includes determining gain relations between a gain of a first satellite antenna which transmits the down-link in a direction of the receiver and a gain of a second satellite antenna which transmits an interfering signal in the direction of the receiver, sampling and scaling interfering signals at the satellite based on the gain relations, and estimating a co-channel down-link interference component that the down-link signal is expected to experience on a path to the receiver.
1. A method for minimizing co-channel interference on-board a satellite, the method comprising:
post-compensating of an up-link signal received by the satellite, the up-link signal comprising a desired signal transmitted by a first transmitter and an interfering signal transmitted by a second transmitter, the post-compensating comprising:
identifying the interfering signal based on post-compensation parameters including locations of the first transmitter and the second transmitter, carrier power levels of the desired signal and the interfering signal, and satellite antenna characteristics;
determining gain relations between a satellite receiver antenna gain in a direction of the first transmitter and a satellite receiver antenna gain in a direction of the second transmitter;
sampling and scaling the interfering signal at the satellite based on the determined gain relations; and
estimating, based on the sampled and scaled interfering signal, a co-channel up-link interference component in the up-link signal,
wherein the post-compensated up-link signal is represented by
Z 1 ( t )=[Delta R/R 22 ]·Y 1 ( t ),
where
DeltaR=(R 11 ·R 22 −R 12 ·R 21 ),
Y 1 (t) is the desired signal transmitted by the first transmitter, R 11 is the satellite receiver antenna gain in the direction of the first transmitter, R 12 is the satellite receiver antenna gain in the direction of the second transmitter, R 22 is an antenna gain of another satellite receiver in the direction of the second transmitter, and R 21 is an antenna gain of the other satellite receiver in the direction of the first transmitter.
2. The method of claim 1 , wherein the post-compensating further comprises:
subtracting the estimated co-channel up-link interference component from the up-link signal.
3. The method of claim 1 , wherein the post-compensating further comprises:
multiplying a weight factor associated with the estimated co-channel up-link interference component with the up-link signal.
4. The method of claim 1 , wherein the post-compensation parameters are stored in a database, wherein the post-compensation parameters are dynamically updated in response to changes in at least one of terrestrial networks, satellite configuration, or carrier operational parameters.
5. A method for minimizing co-channel interference on-board a satellite, the method comprising:
pre-compensating of a down-link signal to be transmitted from the satellite to a receiver, the down-link signal transmitted from a first satellite transmitter antenna and an interfering signal, which interferes with the down-link signal, transmitted from a second satellite transmitter antenna, the pre-compensating comprising:
determining gain relations between a gain of the first satellite transmitter antenna in a direction of the receiver and a gain of the second satellite transmitter antenna in the direction of the receiver;
sampling and scaling interfering signals at the satellite based on the determined gain relations; and
estimating a co-channel down-link interference component that the down-link signal is expected to experience on a path to the receiver,
wherein the pre-compensated down-link signal is represented by:
S 1 ( t )=[Delta T/T 22 ]·Z 1 ( t ),
where Z 1 (t) is an up-link signal or a signal resulting from a previous post-compensation process and DeltaT=(T 11 ·T 22 −T 12 ·T 21 ),
T 11 is the gain of the first satellite transmitter antenna in the direction of the receiver, T 21 is the gain of the second satellite transmitter antenna in the direction of the receiver, T 12 is a gain of the first satellite transmitter antenna in a direction of another receiver, and T 22 is the gain of the second satellite transmitter antenna in the direction of the other receiver.
6. The method of claim 5 , wherein the pre-compensating further comprises:
subtracting the estimated co-channel downlink interference component from the down-link signal.
7. The method of claim 5 , wherein the pre-compensating further comprises:
multiplying a weight factor associated with the estimated co-channel downlink interference component with the down-link signal.
8. A method for minimizing co-channel interference on-board a satellite, the method comprising:
post-compensating of an up-link signal received by the satellite, the up-link signal comprising a desired signal transmitted by a first transmitter and an interfering signal transmitted by a second transmitter, the post-compensating comprising:
identifying the interfering signal based on post-compensation parameters including locations of the first transmitter and the second transmitter, carrier power levels of the desired signal and the interfering signal, and satellite antenna characteristics;
determining gain relations between a satellite receiver antenna gain in a direction of the first transmitter and a satellite receiver antenna gain in a direction of the second transmitter,
sampling and scaling the interfering signal at the satellite based on the determined gain relations; and
estimating, based on the sampled and scaled interfering signal, a co-channel up-link interference component in the up-link signal; and
pre-compensating of a down-link signal to be transmitted from the satellite to a receiver, the down-link signal transmitted from a first satellite transmitter antenna and an interfering signal, which interferes with the down-link signal, transmitted from a second satellite transmitter antenna, the pre-compensating comprising:
determining gain relations between a gain of the first satellite transmitter antenna in a direction of the receiver and a gain of the second satellite transmitter antenna in the direction of the receiver;
sampling and scaling interfering signals at the satellite based on the determined gain relations; and
estimating a co-channel down-link interference component that the down-link signal is expected to experience on a path to the receiver,
wherein the post-compensated up-link signal is represented by
Z 1 ( t )=[Delta R/R 22 ]·Y 1 ( t ),
where DeltaR=(R 11 ·R 22 −R 12 ·R 21 )
Y 1 (t) is the desired signal transmitted by the first transmitter, R 11 is the satellite receiver antenna gain in the direction of the first transmitter, R 12 is the satellite receiver antenna gain in the direction of the second transmitter, R 22 is an antenna gain of another satellite receiver in the direction of the second transmitter, and R 21 is an antenna gain of the other satellite receiver in the direction of the first transmitter.
9. The method of claim 8 , wherein the post-compensating further comprises:
subtracting the estimated co-channel up-link interference component from the up-link signal.
10. The method of claim 8 , wherein the post-compensating further comprises:
multiplying a weight factor associated with the estimated co-channel up-link interference component with the up-link signal.
11. The method of claim 8 , wherein the post-compensation parameters are stored in a database, wherein the post-compensation parameters are dynamically updated in response to changes in at least one of terrestrial networks, satellite configuration, or carrier operational parameters.
12. The method of claim 8 , wherein the pre-compensating further comprises:
subtracting the estimated co-channel downlink interference component from the down-link signal.
13. The method of claim 8 , wherein the pre-compensating further comprises:
multiplying a weight factor associated with the estimated co-channel downlink interference component with the down-link signal.
14. A method for minimizing co-channel interference on-board a satellite, the method comprising:
post-compensating of an up-link signal received by the satellite, the up-link signal comprising a desired signal transmitted by a first transmitter and an interfering signal transmitted by a second transmitter, the post-compensating comprising:
identifying the interfering signal based on post-compensation parameters including locations of the first transmitter and the second transmitter, carrier power levels of the desired signal and the interfering signal, and satellite antenna characteristics; and
pre-compensating of a down-link signal to be transmitted from the satellite to a receiver, the down-link signal transmitted from a first satellite transmitter antenna and an interfering signal, which interferes with the down-link signal, transmitted from a second satellite transmitter antenna, the pre-compensating comprising:
determining gain relations between a gain of the first satellite transmitter antenna in a direction of the receiver and a gain of the second satellite transmitter antenna in the direction of the receiver;
sampling and scaling interfering signals at the satellite based on the determined gain relations; and
estimating a co-channel down-link interference component that the down-link signal is expected to experience on a path to the receiver,
wherein the pre-compensated down-link signal is represented by:
S 1 ( t )=[Delta T/T 22 ]·Z 1 ( t ),
where Z 1 (t) is an up-link signal or a signal resulting from a previous post-compensation process and DeltaT=(T 11 ·T 22 −T 12 ·T 21 ),
T 11 is the gain of the first satellite transmitter antenna in the direction of the receiver, T 21 is the gain of the second satellite transmitter antenna in the direction of the receiver, T 12 is a gain of the first satellite transmitter antenna in a direction of another receiver, and T 22 is the gain of the second satellite transmitter antenna in the direction of the other receiver.
15. A system for minimizing co-channel interference on-board a satellite, the system comprising:
a post-compensation unit which post-compensates an up-link signal received by the satellite, the up-link signal comprising a desired signal transmitted by a first transmitter and an interfering signal transmitted by a second transmitter, wherein the post-compensation unit post-compensates the up-link signal by identifying the interfering signal based on post-compensation parameters including locations of the first transmitter and the second transmitter, carrier power levels of the desired signal and the interfering signal, and satellite antenna characteristics,
wherein the post-compensation unit comprises:
a determination unit which determines gain relations between a satellite receiver antenna gain in a direction of the first transmitter and a satellite receiver antenna gain in a direction of the second transmitter:
a sampling unit which samples and scales the interfering signal at the satellite based on the determined gain relations; and
an estimating unit which estimates, based on the sampled and scaled interfering signal, a co-channel up-link interference component in the up-link signal,
wherein the post-compensation unit represents the post-compensated up-link signal by
Z 1 ( t )=[Delta R/R 22 ]·Y 1 ( t ),
where DeltaR=(R 11 ·R 22 −R 12 ·R 11 ),
Y 1 (t) is the desired signal transmitted by the first transmitter, R 11 is the satellite receiver antenna gain in the direction of the first transmitter, R 12 is the satellite receiver antenna gain in the direction of the second transmitter, R 22 is an antenna gain of another satellite receiver in the direction of the second transmitter, and R 21 is an antenna gain of the other satellite receiver in the direction of the first transmitter.
16. The system of claim 15 , wherein the post-compensation unit further comprises:
a subtracting unit which subtracts the estimated co-channel up-link interference component from the up-link signal.
17. The system of claim 15 , wherein the post-compensation unit further comprises:
a multiplication unit which multiplies a weight factor associated with the estimated co-channel up-link interference component with the up-link signal.
18. The system of claim 15 , wherein the post-compensation parameters are stored in a database, wherein the post-compensation parameters are dynamically updated in response to changes in at least one of terrestrial networks, satellite configuration, or carrier operational parameters.
19. A system for minimizing co-channel interference on-board a satellite, the system comprising:
a pre-compensation unit which pre-compensates a down-link signal to be transmitted from the satellite to a receiver, the down-link signal transmitted from a first satellite transmitter antenna and an interfering signal, which interferes with the down-link signal, transmitted from a second satellite transmitter antenna, the pre-compensation unit comprising:
a determination unit which determines gain relations between a gain of the first satellite transmitter antenna in a direction of the receiver and a gain of the second satellite transmitter antenna in the direction of the receiver;
a sampling unit which samples and scales interfering signals at the satellite based on the determined gain relations; and
an estimating unit which estimates a co-channel down-link interference component that the down-link signal is expected to experience on a path to the receiver,
wherein the pre-compensation unit represents the pre-compensated down-link signal by:
S 1 ( t )=[Delta T/T 22 ]·Z 1 ( t ),
where Z 1 (t) is an up-link signal or a signal resulting from a previous post-compensation process and DeltaT=(T 11 ·T 22 −T 12 ·T 21 ),
T 11 is the gain of the first satellite transmitter antenna in the direction of the receiver, T 21 is the gain of the second satellite transmitter antenna in the direction of the receiver, T 12 is a gain of the first satellite transmitter antenna in a direction of another receiver, and T 22 is the gain of the second satellite transmitter antenna in the direction of the other receiver.
20. The system of claim 19 , wherein the pre-compensation unit further comprises:
a subtracting unit which subtracts the estimated co-channel downlink interference component from the down-link signal.
21. The system of claim 19 , wherein the pre-compensating further comprises:
a multiplication unit which multiplies a weight factor associated with the estimated co-channel downlink interference component with the down-link signal.
22. A system for minimizing co-channel interference on-board a satellite, the system comprising:
a post-compensation unit which post-compensates an up-link signal received by the satellite, the up-link signal comprising a desired signal transmitted by a first transmitter and an interfering signal transmitted by a second transmitter, wherein the post-compensation unit post-compensates the up-link signal by identifying the interfering signal based on post-compensation parameters including locations of the first transmitter and the second transmitter, carrier power levels of the desired signal and the interfering signal, and satellite antenna characteristics, wherein the post-compensation unit comprises:
a determination unit which determines gain relations between a satellite receiver antenna gain in a direction of the first transmitter and a satellite receiver antenna gain in a direction of the second transmitter:
a sampling unit which samples and scales the interfering signal at the satellite based on the determined gain relations; and
an estimating unit which estimates, based on the sampled and scaled interfering signal, a co-channel up-link interference component in the up-link signal; and
a pre-compensation unit which pre-compensates a down-link signal to be transmitted from the satellite to a receiver, the down-link signal transmitted from a first satellite transmitter antenna and an interfering signal, which interferes with the down-link signal, transmitted from a second satellite transmitter antenna, the pre-compensation unit comprising:
a determination unit which determines gain relations between a gain of the first satellite transmitter antenna in a direction of the receiver and a gain of the second satellite transmitter antenna in the direction of the receiver;
a sampling unit which samples and scales interfering signals at the satellite based on the determined gain relations; and
an estimating unit which estimates a co-channel down-link interference component that the down-link signal is expected to experience on a path to the receiver,
wherein the post-compensation unit represents the post-compensated up-link signal by
Z 1 ( t )=[Delta R/R 22 ]·Y 1 ( t ),
where DeltaR=(R 11 ·R 22 −R 12 ·R 21 ),
Y 1 (t) is the desired signal transmitted by the first transmitter, R 11 is the satellite receiver antenna gain in the direction of the first transmitter, R 12 is the satellite receiver antenna gain in the direction of the second transmitter, R 22 is an antenna gain of another satellite receiver in the direction of the second transmitter, and R 21 is an antenna gain of the other satellite receiver in the direction of the first transmitter.
23. The system of claim 22 , wherein the post-compensation unit further comprises:
a subtracting unit which subtracts the estimated co-channel up-link interference component from the up-link signal.
24. The system of claim 22 , wherein the post-compensation unit further comprises:
a multiplication unit which multiplies a weight factor associated with the estimated co-channel up-link interference component with the up-link signal.
25. The system of claim 22 , wherein the post-compensation parameters are stored in a database, wherein the post-compensation parameters are dynamically updated in response to changes in at least one of terrestrial networks, satellite configuration, or carrier operational parameters.
26. The system of claim 22 , wherein the pre-compensation unit further comprises:
a subtracting unit which subtracts the estimated co-channel downlink interference component from the down-link signal.
27. The system of claim 22 , wherein the pre-compensating further comprises:
a multiplication unit which multiplies a weight factor associated with the estimated co-channel downlink interference component with the down-link signal.
28. A system for minimizing co-channel interference on-board a satellite, the system comprising:
a post-compensation unit which post-compensates an up-link signal received by the satellite, the up-link signal comprising a desired signal transmitted by a first transmitter and an interfering signal transmitted by a second transmitter, wherein the post-compensation unit post-compensates the up-link signal by identifying the interfering signal based on post-compensation parameters including locations of the first transmitter and the second transmitter, carrier power levels of the desired signal and the interfering signal, and satellite antenna characteristics; and
a pre-compensation unit which pre-compensates a down-link signal to be transmitted from the satellite to a receiver, the down-link signal transmitted from a first satellite transmitter antenna and an interfering signal, which interferes with the down-link signal, transmitted from a second satellite transmitter antenna, the pre-compensation unit comprising:
a determination unit which determines gain relations between a gain of the first satellite transmitter antenna in a direction of the receiver and a gain of the second satellite transmitter antenna in the direction of the receiver;
a sampling unit which samples and scales interfering signals at the satellite based on the determined gain relations; and
an estimating unit which estimates a co-channel down-link interference component that the down-link signal is expected to experience on a path to the receiver,
wherein the pre-compensation unit represents the pre-compensated down-link signal by:
S 1 ( t )=[Delta T/T 22 ]·Z 1 ( t ),
where Z 1 (t) is an up-link signal or a signal resulting from a previous post-compensation process and DeltaT=(T 11 ·T 22 −T 12 ·T 21 ),
T 11 is the gain of the first satellite transmitter antenna in the direction of the receiver, T 21 is the gain of the second satellite transmitter antenna in the direction of the receiver, T 12 is a gain of the first satellite transmitter antenna in a direction of another receiver, and T 22 is the gain of the second satellite transmitter antenna in the direction of the other receiver.