The LInear amplification with Nonlinear Component transmitter is a high power efficient architecture for radio communication systems. Nevertheless, this architecture is sensitive to mismatches between the two paths and its efficiency performances are dependent on the power amplification stage topology. Additively, careful attention has to be paid to baseband performances in terms of sampling rate, Digital to Analog Converters (DACs) resolution, reconstruction filter bandwidth... In this paper, we present the specification of the reconstruction filters for a single carrier WCDMA 3GPP base station transmitter and this, according to the Power Amplifier (PA) class (switched mode (SMPA) or AB class). We address the impact of the class of the PAs on the overall performances and on the reconstruction filters specifications. Admissible time delays and gain mismatches between the two paths will also be quantified.

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This work investigates the impact of dielectric loading on the RF performances of integrated VCO and PLL systems. Both On-Chip and System-Level (On-Board) experimental characterizations are carried out to determine influence of various substances (resins, salted water, petroleum, sugar mixture) on frequency variations, taking into account the importance of mechanical fixture. Calibration and monitoring aspects are discussed towards real-time measurement of aqueous concentrations of liquids for medical applications.