digital beamforming; phased arrays; Satellite communications; Beam pattern; Digital beamforming; Growing demand; High capacity; High-capacity; Lattice beams; LEO Constellation; Phased-arrays; Triangular-lattice; Computer Networks and Communications; Array signal processing; Fast Fourier transforms; Antennas; Satellites; Lattices; Interference; Structural beams; Discrete Fourier transforms
Abstract :
[en] The growing demand for high-capacity satellite communications, particularly in Medium Earth Orbit (MEO) and Low Earth Orbit (LEO) constellations, has made digital beamforming essential to enhance system performance by producing simultaneous beams. Among various techniques, Fast Fourier Transform (FFT)-based beamforming is favored for its power efficiency and effectiveness in terms of Signal-to-Interference Ratio (SIR) when the number of antennas matches the number of beams. However, to reduce costs and complexity in the RF-chain, the number of antennas is often reduced relative to the number of beams, compromising beam pattern orthogonality and degrading the SIR. This article investigates the combination of techniques to mitigate this degradation, including regular spaced triangular-lattice beam pattern and antennas, hexagonal subarray lattices, 4-color scheme, and tapering, all working synergistically to enhance the overall SIR. The proposed method employs regular hexagonal sampling grids, enabling the generation of triangular-lattice beam pattern using standard rectangular FFT-routines. By avoiding interpolation, this approach minimizes artifacts in beam pattern generation over wide fields of view and preserves the SIR, making it particularly suitable for satellite applications. The simulation results demonstrate that the proposed strategy, using a 16-point FFT-beamforming approach with only 100 antenna elements, significantly enhances the SIR by nearly 20 dB compared to the regular scenario.
Precision for document type :
Review article
Disciplines :
Electrical & electronics engineering
Author, co-author :
VASQUEZ-PERALVO, Juan Andres ; University of Luxembourg > Interdisciplinary Centre for Security, Reliability and Trust (SNT) > SigCom
HA, Vu Nguyen ; University of Luxembourg > Interdisciplinary Centre for Security, Reliability and Trust (SNT) > SigCom
GARCES SOCARRAS, Luis Manuel ; University of Luxembourg > Interdisciplinary Centre for Security, Reliability and Trust (SNT) > SigCom
NGUYEN, Ti Ti ; University of Luxembourg > Interdisciplinary Centre for Security, Reliability and Trust (SNT) > SigCom
CUIMAN MARQUEZ, Raudel ; University of Luxembourg > Interdisciplinary Centre for Security, Reliability and Trust (SNT) > SigCom
European Space Agency through “EFFICIENT DIGITAL BEAMFORMING TECHNIQUES FOR ON-BOARD DIGITAL PROCESSORS (EGERTON)” Luxembourg National Research Fund (FNR), through the CORE Project (C³): Cosmic Communication Construction
Funding text :
This work was supported in part by the European Space Agency through \u201CEFFICIENT DIGITAL BEAMFORMING TECHNIQUES FOR ON-BOARD DIGITAL PROCESSORS (EGERTON)\u201D (Opinions, interpretations, recommendations and conclusions presented in this paper are those of the authors and are not necessarily endorsed by the European Space Agency) under Project 4000134678/21/UK/AL, and in part by the Luxembourg National Research Fund (FNR), through the CORE Project (C3): Cosmic Communication Construction under Grant C23/IS/18116142/C3\u02C6.
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