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Summarization: In this paper, we investigate how the incident power at the tag affects the backscattered signal that reaches the reader. It is shown experimentally and theoretically that the backscattered complex signal, i.e. magnitude and phase, changes significantly with respect to the incident power at the tag’s antenna. This effect is neglected in prior art and is due to the change of the input impedance of the tag’s front end, due to the presence of non-linear components, like the rectifier’s diodes. Measured deviation of 14dBs and phase shift of 100 degrees is reported herein. These variations might lead to large localization errors, depending on the method and the measured quantity, unless the localization algorithm accounts for the expected variability. Παρουσιάστηκε στο: 2021 IEEE International Conference on RFID Technology and Applications

This paper presents the design and implementation of a wideband power amplifier (PA) suitable for applications using signals with large peak-to-average-power-ratio (PAPR). The proposed design approach is based on reducing the load modulation factor compared to conventional Doherty PA. To demonstrate the principle, a PA that operates between 2.55 GHz and 3.8 GHz has been implemented and tested. In this frequency range, the measured peak output power is 49.3 ± 0.5 dBm and the measured drain efficiency is between 47-60 % for output power levels corresponding to 8 dB output back-off (OBO).

Spiking Neural Network (SNN) acts as a part of the third generation of Artificial Neural Networks (ANNs). Evolving Spiking Neural Network (ESNN) is one of the most broadly utilized among in SNN models in numerous current research works. During the classification process, ESNN model acts as a classifier and three parameters are used in this article. However, the parameters are needed to set manually before the classification process. To solve the stated problems, ESNN required an optimizer that able to optimize the three parameters such as similarity value, modulation factor and proportion factor. The best estimations of parameters are adaptively chosen by Harmony Search Algorithm (HSA) to abstain from choosing appropriate values for specific issues through the trial-and-error approach. Therefore, this article proposed the integration of ESNN as a classifier and HSA as an optimizer for parameter optimization. The experimental results give favorable accuracy rates via the hybrid of ESNN and HSA.

We show that optimizing pre- and post-dispersion compensation can increase the section of low fourth-order modulation factor in the transmission link. In experiments, we demonstrate reach increase for 32 Gbaud PM-16QAM by using 25% to 50% pre-compensation of the dispersion.

The driver active assistances have gained recently in importance and become usual features in commercialized vehicles. Nevertheless, the sharing of the vehicle control with the driver, especially for the steering assistances, is an open issue. The rear wheels steering could be an answer to this question. This study contains the development of a control law for the rear steering able to provide lane departure avoidance and lane keeping. The design of the control law is casted as a LMI (Linear Matrix Inequality) optimization problem in order to take into account constraints, as the rear steering actuator limitation. A modulation factor is added to allow a flexible activation strategy of the rear steering assistance. Preliminary simulation results are presented to explain the concept.

Based on the theory of energy conservation, the Energy Balance (EB) model of a PSM (Pulse Skip Modulation) converter in DCM (Discontinuous Current Mode) is proposed in this paper. The relationships of the output voltage versus modulation factor M and load resistances R are given. The stability of a PSM converter in DCM is analyzed based on this proposed EB model. Simulation results show that chaos never occurs but bifurcations happen for a PSM converter in DCM. The PSM converter will be stable at either period-(n+m) bifurcation mono-cycle stabilization or (ni +mi) multi-cycle stabilization. ni=1 or mi=1 always occurring whenever a PSM converter operating in DCM is proved by simulation. The boundary resistances of period-(n+m) bifurcation and the output voltage ripples are also given in this paper.

The JT-60U gyrotron has a triode electron gun, which enables to control its oscillation output by adjusting its anode voltage. The output was successfully recovered by anode voltage control when it was terminated. Moreover, the output was modulated at 0.7 MW up to 500 Hz with modulation factor 80 %.

Analysis is presented of a linear dynamic model, around the static operation point, for a series resonant converter operating with small amplitude modulating signal and a modulation factor less than one. Comparison of the theoretical results with those found experimentally shows the validity of the proposed model also as regards the shift of the dominant pole with switching frequencies approximate to the resonance frequency. This happens to be particularly precise for values of Q greater than 1.5 where the first harmonic approach is much more valid. In conclusion, the proposed model approximates very closely to the behavior of the physical system for values of f/sub S//f/sub O/ greater than 0.6 and values of Q greater than 1.5. >