The advancement and miniaturization of body implanted medical devices pose several challenges to Ultrasonic Transcutaneous Energy Transfer (UTET), such as the need to reduce the size of the piezoelectric resonator, and the need to maximize the UTET link power-transfer efficiency. Accordingly, the same piezoelectric resonator that is used for energy harvesting at the body implant, may also be us...

The RF ion source at Spallation Neutron Source has been upgraded to meet higher beam power requirement. One important subsystem for efficient operation of the ion source is the 2MHz RF impedance matching network. The real part of the antenna impedance is very small and is affected by plasma density for 2MHz operating frequency. Previous impedance matching network for the antenna has limited tun...

A new design of coplanar waveguide (CPW)-fed antenna with circular polarization (CP) and excellent impedance matching is presented. In this design a pair of circular-shaped slits is applied to opposite corners of the slot for enhancing the impedance matching and realizes bandwidth of 134.43% across 2.98-15.20 GHz for VSWR≤2. Furthermore this structure exhibits axial ration bandwidth (ARBW) of 3...

A big challenge in studying organic rich shale is to predict its kerogen content and maturity from indirect observations. Kerogen maturation changes shale texture; for example, it generates microcracks and fractures in the matrix. Assessment of maturity from indirect measurements can be greatly enhanced by exploiting any existing correlations between physical properties, microstructure, and ker...

Measurements of middle ear (ME) acoustic power flow (power reflectance, power absorption, and transmittance) and normalized impedance (acoustic resistance, acoustic reactance, and impedance magnitude) were compared for their utility in clinical applications. Transmittance, a measure of the acoustic power absorbed by the ME, was found to have several important advantages over other measures of a...

An efficient rectifier system along with an impedance matching network is proposed in this article. Impedance matching network is designed using two microstrip lines. Rectifier system for better RF to DC conversion is designed using a bridge rectifier. The proposed rectifier system provides a maximum efficiency of 50%. The impedance matching network improves the overall system performances sign...

Identifying the scatterers and obtaining accurate estimates of ultrasonic scatterer sizes are beneficial adjuncts to characterize (diagnose) disease from ultrasonic backscatterer measurements. A new scatterer size estimation technique has been developed that is based on a 3D acoustic impedance map. Ultrasonic scatterer estimation techniques rely extensively on form factor functions to obtain es...

In this paper, a summary of our work in the area of tunable microwave circuits based on thin film ferroelectrics is presented. First, a technique is introduced to improve the linearity of thin film ferroelectric tunable capacitors. Measurements show an improvement in the 3rd order intermodulation point at the input (IIP3) of 16 dB. Next, the design and fabrication of an impedance tuner employin...