Proposal of QAM-OFDM System with IDAR Method for Non-Linear Satellite Channel

The future satellite communication systems are required to support the higher transmission data rate for providing multimedia services by employing the efficient modulation method such as multi-level QAM. However, the employment of conventional single carrier transmission method with multi-level QAM would cause the fatal degradation of signal quality due to the non-linear amplifiers located at the Earth station and satellite. To overcome this problem, this paper proposes the multi-level QAM-OFDM technique with IDAR method designed for satellite channel. In the IDAR method, the characteristics of non-linear amplifiers are required to be known at the receiver. This paper also proposes the estimation method for the characteristics of the non-linear amplifiers by using low PAPR preamble symbols. Various computer simulations are conducted in this paper to verify the effectiveness of proposed method in the non-linear satellite channel