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Additional file 1. Methods. Table S1: CT1812 pharmacokinetic parameters in plasma and CSF of two AD patients after a single 560-mg oral dose.

International audience; Digital predistorsion (DPD) is a commonly used approach to compensate for the power amplifiers (PA) nonlinearities and memory effects as well as to improve its power efficiency. To alleviate the restriction brought by high peak-to-average power ratio (PAPR) of input signals, crest factor reduction (CFR) is needed for higher efficiency. In modern communication systems, power of transmitted signals gets lower, which makes complexities of CFR and DPD become non-negligible. This paper proposes a new approach to realize a joint CFR and DPD model using neural networks (NN). The modeling accuracy is guaranteed by a new proposed augmented iterative learning control (AILC) algorithm for the NN training signals. Compared with conventional ILC, the proposed AILC is shown more robust according to simulation and experimental results. The proposed AILC-based NN-CFRDPD is experimentally evaluated on different test benches.

International audience; Neural networks (NN) are efficient techniques for behavioral modeling of power amplifiers (PA). This paper proposes a genetic algorithm to determine the optimal hyperparam-eters of the NN model for a PA. Different activation functions are compared. The necessary number of training epochs is also studied to get an optimal solution with a significantly reduced computational complexity. Experimental measurements on a PA with different signals validate the NN models determined by the proposed method.

International audience; This letter proposes a method to study the tradeoff between the power amplifier (PA) power efficiency and the corresponding digital predistortion (DPD) model complexity needed for its linearization. The linearization performance estimated with the adjacent channel power ratio (ACPR) is treated as a control variable. In order to study at different PA operating points (OPs), an algorithm is proposed to trace approximate Pareto fronts of the ACPR versus the DPD model number of coefficients. Crest factor reduction is applied when the backoff of the OP is less than the peak-to-average power ratio (PAPR) of the long-term evolution (LTE) signal. Experimental results on a PA with an LTE signal give interesting insights on the relationship between DPD complexity and PA power efficiency.

International audience; The power efficiency and the linearity of a power amplifier (PA) depend on its operating point. A high efficiency generally corresponds to poor linearity. To optimize the efficiency/linearity trade-off, crest factor reduction (CFR) techniques are classically implemented along with digital predistortion (DPD) to control the PA operating point. Joint CFR/DPD can be realized with a single model so that the running complexity of the CFR is negligible. This paper fully explores the clipping-and-bank-filtering (CABF) method for joint CFR/DPD and extends it to the multi-carrier case with validation on experimental results. Compared with conventional approaches, it provides either better linearization performance or lower complexity at the same PA operating point. The study is completed with a discussion on the choice of windows in the filter bank. The proposed CABF-based joint CFR/DPD model is then experimentally evaluated on a test bench with two PAs using single-carrier and 2-carrier 20~MHz long term evolution (LTE) signals as the stimulus.