Behavioral Modeling and linearization of a mm-wave Power Amplifier

The use of digital predistortion for linearizing a millimeter-wave power amplifier (PA) is investigated. A PA operating at 38 GHz is designed using an accurate non-quasi-static transistor model, taking into account both short- and long-term memory effects. A realistic test signal is then used for the identification of a nonlinear auto-regressive moving average (NARMA) behavioral model of the PA. The NARMA-based digital predistorter is then derived and formulated in terms of basic predistortion cells, especially suitable for efficient implementation in an FPGA. The performance of the predistortion solution is preliminarily assessed by means of computer simulations

Behavioral modeling and digital predistortion for the linearization of a mm-wave Power Amplifier

The use of Digital Predistortion (DPD) for linearizing a millimeter-wave Power Amplifier (PA) is investigated. A PA operating at 38 GHz is designed using an accurate nonquasi-static transistor model taking into account both short- and long-term memory effects. A realistic test signal is then used for the identification of a Nonlinear Auto-Regressive Moving Average (NARMA) behavioral model of the PA. The NARMA-based digital predistorter is then derived and formulated in terms of Basic Predistortion Cells, especially suitable for efficient implementation in an FPGA. The performance of the predistortion solution is preliminarily assessed by means of computer simulations

Multicarrier Digital Pre-distortion/ EqualizationTechniques for Non-linear Satellite Channels

Two key advances are envisaged for future missions: (a) spectrally efficienttransmission to meet the increasing demand and (b) sharing of satellite capacityamong different links to meet power/mass requirements. Joint amplification ofmultiple-carrier DVB-S2 signals using a single High-Power Amplifier (HPA) is aparticular application of satellite resource sharing. However, effects specific to sucha scenario that degrade power and spectral efficiencies include (a) an increasedAdjacent Channel Interference caused by non-linear characteristic of the HPA and(b) increased peak to average power ratio. The paper studies signal processingtechniques – digital pre-distortion (DPD) at the gateway and equalization (EQ) atthe User Terminal – to mitigate the non-linear effects and improve power as well asspectral efficiencies. While the algorithms for DPD and EQ are described inliterature, their use in multi-carrier scenario is novel and poses new challenges thatare investigated in the paper.QC 20131218</p