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Title RF communications system block model for evaluation of non-linear HPAs
Translated title RF communications system block model for evaluation of non-linear HPAs
Author Nørgaard, Kristjan S. (Copenhagen University College of Engineering, IHK)
Supervisor Gothelf, Ulrich V.
Institution Ingeniørhøjskolen i København, IHK, DK-2750 Ballerup, Denmark
Thesis level Bachelor thesis
Education Diplomingeniør, Elektronik
Education !!Diplomingeniør, elektronik
Publication date 2013-01
Abstract This report describes the development of a RF communications system block model for evaluation of non-linear L-band HPAs. The model is used to simulate RF link degradations in terms of Error Vector Magnitude (EVM) and transmit power spectral regrowth caused by a non-linear High Power Amplifier (HPA), when used in a User Terminal for a satellite communications system with digital modulation schemes.
The model is implemented in Matlab, and functions for generating an M-QAM modulated baseband signal, and a complex envelope baseband model of the non-linear HPA are described. The complex envelope baseband model of the non-linear HPA is based on measured AM-AM and AM-PM transfer characteristics. Functions to calculate power spectral density, 16-QAM signal constellations, error minimization, and EVM are also developed.
Furthermore the report describes the RF hardware design of a LD-MOS based HPA. Power sweep measurements, transmitted spectrum, and EVM measurements performed on this amplifier and for comparison, a GaN based power amplifier, are used to verify the accuracy of the RF communications system block model.
Abstract This report describes the development of a RF communications system block model for evaluation of non-linear L-band HPAs. The model is used to simulate RF link degradations in terms of Error Vector Magnitude (EVM) and transmit power spectral regrowth caused by a non-linear High Power Amplifier (HPA), when used in a User Terminal for a satellite communications system with digital modulation schemes.
The model is implemented in Matlab, and functions for generating an M-QAM modulated baseband signal, and a complex envelope baseband model of the non-linear HPA are described. The complex envelope baseband model of the non-linear HPA is based on measured AM-AM and AM-PM transfer characteristics. Functions to calculate power spectral density, 16-QAM signal constellations, error minimization, and EVM are also developed.
Furthermore the report describes the RF hardware design of a LD-MOS based HPA. Power sweep measurements, transmitted spectrum, and EVM measurements performed on this amplifier and for comparison, a GaN based power amplifier, are used to verify the accuracy of the RF communications system block model.
Pages 172
Keywords HPA non-linear M-QAM EVM PSD Block model LD-MOS RF communications AM-AM AM-PM Matlab ; HPA non-linear M-QAM EVM PSD Block model LD-MOS RF communicattions AM-AM AM-PM Matlab
External partner Ledere og medarbejdere i private virksomheder
Admin Creation date: 2013-01-01    Update date: 2013-03-14    Source: ihk    ID: ihk-12812489    Original MXD