Signal Cancellation for Satellite Frequency Reuse by Carrier Super-Positioning Multi-level Modulation

This paper proposes a design of frequency reuse for satellite communications by carrier super-positioning for multi-level modulation which is going to be widely used. In the frequency super-positioning, the interference is caused by the undesired signal remained by the imperfectness of replica. The imperfectness is due to the phase and amplitude error between undesired signal and replica and degrades the transmission performance. This paper is trying to solve this issue by minimizing the imperfectness to satisfy multi-level modulation transmission and by making precise replica simple. We show here a design approach for implementing accurate signal canceller for QPSK and 16QAM transmission. A simple method to generate replica is also proposed as an alternative. This method does not require satellite one round trip delay measurement which was required in the conventional canceller.