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This work deals with the possibility to create a high temperature surface acoustic waves (SAW) sensor based on the use of a new piezoelectric material : Ba2TiSi2O8.The wave propagation in the material is at first studied and compared to another material used for harsh environment : LiTaO3. Then a SAW resonator on Ba2TiSi2O8 is designed.
At present the great interest of researchers is stimulated by piezoelectric lateral electric field excited resonators the electric field of which penetrates in contacting vacuum. The characteristics of resonator were studied at moving off its free side the glass plate with a strongly conductive film. It has been shown that parallel resonance frequency unambiguously ties with the gap width between...
A microwave applicator is presented that realizes the theranostic approach by providing two operation modes to detect and treat tumor cells, exemplary in the liver. The tool is based on a planar sensor structure with Split Ring Resonators (SRR) as key elements. For the detection, changes in dielectric properties caused by tissue abnormalities are evaluated by analyzing shifts in the resonance frequency...
Electromechanical characterization of piezoceramic bulk elements around resonance is usually done with low-level continuous excitation signals at room temperature, but in real applications such elements are driven with different types of electrical signals, usually at higher levels and at different ambient temperatures. Both homemade and commercial soft and hard PZT piezoceramic elements were characterized...
A dual-frequency reconfigurable sensing antenna is proposed for temperature monitoring. A double-patch antenna with two slots is designed for dual-frequency matching with a RFID chip at Ultra High Frequency (UHF) band. Thermal switches are added to the two slots to reconfigure the resonant frequencies according to the surrounding temperature. The proposed antenna exhibits a high sensitivity, a compact...
The use of radio frequency techniques is increasing in various applications in biodetection as well diagnostic and therapeutic medicine. This work reports for radio frequency labelfree based systematic biodetection platform; which can be used to identify several types of viruses. The presented technique is able to identify the virus type with few minutes without the use of any biomarkers. A coaxial...
The performance of vector nozzle is evaluated by the aero-engine vector nozzle measuring platform. The airflow temperature of the vector nozzle is as high as 1100K in the thermal test, which is not conducive to measure the thrust vector. There are several factors that affect the vector thrust measurement. The expansion of the heated vector simulation device generates tensile force on the floating...
SF6 based Gas Insulated Switchgear (GIS) are widely used for High Voltage (HV) applications. Due to the environmental impact of SF6 gas, strict regulations have been laid to monitor their use and to restrict their emission from switchgears. Quartz based resonant density sensor is the best technology commercially available today for SF6 monitoring. Frequency response of the sensor is a function of...
This paper presents a stacked multiple coil design for simultaneous multi-parameter narrow-band sensing with RLC-type near-field coupled resonators. The resonant frequency and Q-factor of each RLC sensor is dependent on change of stored energy and loss in response to the parameter of interest. One challenge with these types of sensors is mutual coupling between coils and thus interdependence of parameters...
In this work, we present three different approaches with the objective of increasing the small-signal modulation bandwidth of InP-based VCSELs beyond 20 GHz. The intrinsic bandwidth limitations are overcome thanks to a highly-strained active region, and an ultra-short cavity design. The parasitic cut-off frequency is enhanced by a double-mesa VCSEL design.
This paper presents a simple technique for the calculation of the eigenfrequencies of biconical cavities using the overlapping domain decomposition method in combination with the collocation method, which converges rapidly with increasing number of collocation point pairs and offers a reasonable computation speed.
Thermal domain characterization of a printed log-periodic (LP) antenna is presented. Novel wide-boom geometry is proposed to reduce coupling loss to dipole elements without compromising turn-on frequency. Electro-thermal multiphysics simulation shows that wide-boom improves thermal performance alongside impedance match and gain. Temperature map of the antenna is also measured and experiments verify...
The article concerns the technique of effective and accurate measurement high quality-factor of resonant cavities of Tesla-type that are used in the ILC in superconducting regime. Presented key outcomes that have been obtained using specially developed computerized measuring system with a set of extra UHF parts.
High-resolution computer-controlled oscillator of 2-mm wave-range intended for the low temperature dielectrometer was designed and constructed. The proposed oscillator unit may be used as free-running source as well as phase locked source being included to the frequency synthesis system. Dependence of dielectric loss vs temperature for some diamond-like materials was measured using proposed oscillator...
In this paper, we present new results on the development of an original acoustic waveguides concept based on a Periodically Poled Lithium Niobate transducer. Periodically poled transducers have been investigated recently as an alternative to classical inter-digital transducers for the excitation and detection of guided acoustic waves. We expose here two different structures of RF resonators based...
We report the design of a 50 μW 1.2 MHz monolithic MEMS oscillator embedded in a standard 0.35 μm CMOS with dc-bias lower than 8V. This is the first-time demonstration for a sub-100 μW single-chip CMOS-MEMS oscillator operated in MHz range. To overcome the motional impedance R m > 8 MΩ under sub-10V dc-bias (VP), an ultra-low input referred noise (< 25 fA/rtHz), high gain integrator-differentiator...
On-chip integration of quartz resonators with Si devices opens new opportunities for microsystem miniaturization and enhanced performance. In addition to integrating with electronics, the integration of piezoelectric quartz resonators with other sensors of different material composition is also possible. In this paper, we demonstrate that a VHF SC-cut quartz resonator can be integrated within a high-aspect-ratio...
We demonstrate a synchronously stimulation method for achieving coherent population beating (CPB) atomic clock with the CPB signal which have continuous wave and higher signal-to-noise ratio. In this method we synchronously apply the coherent population trapping (CPT) resonant stimulating lights together with the detuned detecting lights to obtain continuous CPB oscillation signal. Under the stimulation,...
In this paper, a novel mass-sensitivity-based method for field measurement of liquid viscosities using a quartz crystal microbalance (QCM) is presented. And a model which yields a quantitative description of the influence of the liquid properties on the oscillation frequency is established as well. The viscosity of liquids (which loaded on a QCM's center) could be quickly and conveniently obtained...
This paper presents a comparison of several piezoelectrically driven MEMS flexural plate wave (FPW) resonators, all with the electrical interfacing located on the top of the device and fully isolated from the fluidic interface and detection surface on the back of the device, in order to avoid mutual interference. The devices to be compared include devices designed to have wavelengths of 60μm and 100μm,...
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