A Novel Synthetization Approach for Multi Coupled Line Section Impedance Transformers in Wideband Applications

In this paper, a novel synthetization approach is proposed for filter-integrated wideband impedance transformers (ITs). The original topology consists of N cascaded coupled line sections (CLSs) with 2N characteristic impedance parameters. By analyzing these characteristic impedances, a Chebyshev response can be derived to consume N + 2 design conditions. To optimize the left N − 2 variable parameters, CLSs were newly substituted by transmission lines (TLs) to consume the remaining variable parameters and simplify the circuit topology. Therefore, there are totally 2N − N − 2 substituting possibilities. To verify the proposed approach, 25 cases are listed under the condition of N = 5, and 7 selected cases are compared and discussed in detail. Finally, a 75–50 Ω IT with 100% fractional bandwidth and 20 dB bandpass return loss (RL) is designed and fabricated. The measured results meet the circuit simulation and the EM simulation accurately.

Influence of Diffusion and Impedence Parameters on Wave Propagation in Thermoelastic Medium

The aim of the present paper is to study the impact of diffusion and impedance parameters on the propagation of plane waves in a thermoelastic medium for Green and Lindsay theory (G-L) and the Coupled theory (C-T) of thermoelasticity. Results are demonstrated for impedance boundary conditions and the amplitude ratios of various reflected waves against the angle of incidence are calculated numerically. The characteristics of diffusion, relaxation time and impedence parameter on amplitude ratios have been depicted graphically. Some cases of interest are also derived from the present investigation.

Measurement of Impedance of AGM Solar Battery for RAPS Applications

The paper deals with the measurement of the cell impedance parameters during discharging and charging of the AGM 200Ah 6V Sun Power lead acid battery. Real and imaginary part of impedance of the battery were measured by PEIS method. Results of the impedance changes during discharging and charging were plot to Nyquist diagrams. Important values - ohmic resistance RS, charge transfer resistance RCT, double layer capacity CDL and Warburg coefficient σ were found during discharging and charging of the solar battery.

Synthesis of Antennas for Active Glazing Unit with Photovoltaic Modules

The problem considered in the paper concerns the synthesis process of antennas for autonomous semi-passive RFID transponder/sensors dedicated to active glazing units. Glazing units are frequently used in modern multi-storey buildings to create amazing facades. When they are integrated with photovoltaic (PV) modules, active units are obtained. It is desirable, mainly for economic reasons and in order to ensure the high efficiency of a micro-photovoltaic power plant, that active glazing units are equipped with a system for monitoring their operating parameters. In connection with this, design problems occur that fall within the fields of sensor technology and radio communications. The main purpose of the presented study was to prepare appropriate input data for design tools used in the synthesis of antenna systems in the UHF band. Many important issues are considered including: proximity to structural elements of the building facade and PV cells, which disturbs the shape of the radiation pattern and affects the impedance parameters of the antenna system; the need to ensure easy integration of the RFID sensor and the specified object, without significant interference in the production of glazing units; appropriate shaping of the radiation pattern in order to enable reading and writing of the RFID tag from both inside and outside the building; impedance matching to the selected RFID chip in the broadest possible frequency range, etc.

Theoretical model and dynamic wave-amplification effect of the high intensity Helmholtz sound source

Helmholtz sound source consists of Helmholtz resonator and speaker and belongs to a new type of high-intensity sound source. It has potential industrial advantage in the aerodynamic acoustic application for the large amplitude wave. Based on the lumped parameter principle of acoustic impedance, an acoustic theoretical model is suggested. The model reveals the amplification regulation of the sound source on the acoustic wave. Through the acoustic theoretical computation, a dynamic amplification and an amplification limitation are analyzed. The wave-amplification effect attributes to the parameter regulation of the macro, micro, and dynamic-varied sizes of the sound source. The repetitive motion of the vibrating membrane of speaker causes three working states of balance, squeeze, and stretch. The three states act as specific boundary conditions and demonstrate as three different theoretical curves. The theoretical boundary curves codetermine an experimental curve, which essentially limits the practical amplification effect. Nevertheless, the amplification gain of sound pressure amplitude reaches up to 1.8 times, and the potential maximum amplitude reaches up to 3600 Pa (164 dB). The two quantitative characteristics indicate the maximum capability of the sound source on wave-amplification effect. The control sensitivity of the complicated impedance parameters on wave amplification is 0.26 Pa/Hz. The acoustic theoretical model is valuable in the series aspects of the industrial design, manufacture, and application of the sound source. Especially, the theoretical innovation lays the foundation of solid to these aspects.

Odorant Binding Changes the Electrical Properties of Olfactory Receptors at the Nanoscale

The transduction of odorant binding into cellular signaling by olfactory receptors (ORs) is not understood and knowing its mechanism would enable developing new pharmacology and biohybrid electronic detectors of volatile organic com-pounds bearing high sensitivity and selectivity. The electrical characterization of ORs in bulk experiments is subject to microscopic models and assumptions. We have directly determined the nanoscale electrical properties of ORs immobilized in a fixed orientation, and their change upon odorant binding, using electrochemical scanning tunneling microscopy (EC-STM) in near-physiological conditions. Recordings of current versus time, distance, and electrochemical potential allows determining the OR impedance parameters and their dependence with odorant binding. Our results allow validating OR structural-electrostatic models and their functional activation processes.

Analysis of a method for measuring deposit impedance parameters using charge amplifier and lock-in voltmeter

Parameters such as capacitance and conductivity are measured to describe the properties of a medium, including its moisture content. These methods do not deliver highly accurate results in materials that are characterized by low homogeneity, varied porosity, high conductivity and high water content. This study proposes a more accurate method for estimating the parameters of any medium. In the experimental setup, a charge amplifier and a phase-sensitive voltmeter were applied to determine resistance and capacitance parameters of a medium based on the signals received by the measuring system. The proposed method can be applied to non-homogeneous media containing both dielectric and conductive materials. The described measuring system is composed of two flat electrodes whose size can be adapted to the dimensions of the analyzed medium. A method for processing the sensing signal to determine the impedance characteristics of a medium with the use of a phase-sensitive voltmeter was described. The measuring system was modeled in Matlab/Simulink, and the results were discussed.