Satellite MIMO digital beam-forming under nonlinear high-power amplifier and keyhole
Kwon, Hyuck M.
Pham, Khanh D.
MetadataShow full item record
M. Goswami, H. M. Kwon, K. Pham and J. Lyke, "Satellite MIMO Digital Beam-forming under Nonlinear High-Power Amplifier and Keyhole," 2019 International Conference on Computing, Networking and Communications (ICNC), Honolulu, HI, USA, 2019, pp. 313-317
In a satellite communication (Sat-Com) system, channel coefficients from multiple-input, multiple-output (MIMO) antennas are correlated strongly because of a long propagation distance and a narrow angle spread. This is referred to as a keyhole (KH) channel, which results in a rank deficiency in the MIMO channel and a reduction in the number of simultaneously supportable multiple-access users. In addition, a high-power amplifier (HPA) in a satellite transponder distorts the transmitted signal due to its nonlinearity and memory. The aim of this paper is to study a satellite beamforming (BF) method and to investigate its signal-to-interference-plus-noise ratio (SINR) degradation due to the KH and HPA nonlinearity effects. A closed form of an optimum BF vector is not available due to HPA nonlinearity and memory, and a BF vector with simple complexity is desirable in practice. Therefore, this paper proposes a satellite transponder that uses column vectors from a discrete Fourier transform (DFT) matrix as precoding BF vectors in order for multiple ground terminals to meet their SINR demands.
Click on the DOI link to access the article (may not be free).