The speed of a low-earth orbit (LEO) satellites and the large number of LEO satellites flying on the sky is an obstacle for signal transmission and anti-jamming processing at ground stations.
The Doppler effect due to the LEO satellite rapid moving velocity is a nonneglectable
factor for beamforming techniques, which aim to cancel the co-channel interferences (CCI) caused by other simultaneous satellite communications.
In this work, the minimum variance distortionless response (MVDR) beamforming
technique is used at a ground station to mitigate the CCI problem; however, the Doppler effect becomes a serious problem as it affects the steering vector corresponding to thedirection of the target LEO satellite.
To overcome this problem, we take the Doppler effect into account in the steering
vector associated with the LEO satellite, and then substitute the modified steering vector to the gain constraint in a MVDR beamformer.
Simulation results verify that the proposed method effectively overcome the performance degradation problem of the MVDR beamformer at the ground station. The
solution for this problem can be useful for developing a LEO satellite communication
system.

The speed of a low-earth orbit (LEO) satellites and the large number of LEO satellites flying on the sky is an obstacle for signal transmission and anti-jamming processing at ground stations.
The Doppler effect due to the LEO satellite rapid moving velocity is a nonneglectable
factor for beamforming techniques, which aim to cancel the co-channel interferences (CCI) caused by other simultaneous satellite communications.
In this work, the minimum variance distortionless response (MVDR) beamforming
technique is used at a ground station to mitigate the CCI problem; however, the Doppler effect becomes a serious problem as it affects the steering vector corresponding to thedirection of the target LEO satellite.
To overcome this problem, we take the Doppler effect into account in the steering
vector associated with the LEO satellite, and then substitute the modified steering vector to the gain constraint in a MVDR beamformer.
Simulation results verify that the proposed method effectively overcome the performance degradation problem of the MVDR beamformer at the ground station. The
solution for this problem can be useful for developing a LEO satellite communication
system.

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