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In this paper, a portable system for noninvasive detection of fractures in human bones is presented. A planar microwave ring resonator is used as the sensor. The proposed planar microwave sensor is designed using the finite integration-based CST Microwave Studio and tested on a human bone covered by porcine tissues. Fracture induced in the bone was detected by monitoring the transmission characteristics of the sensor as it scans the affected region. The resonant frequency of the ring resonator has been observed at every scan point, and the values are plotted using iterative curvature-based interpolation, improved new edge directed interpolation, and Lanczos imaging technique. The extent of fracture is then derived from the image. The average accuracy of the detected fracture for Lanczos method of resampling was 98.86%. The specific absorption rate was below the minimum level of 1.6 W/Kg at every point of scanning. Portable noninvasive monitoring of fractures in the tibial bone will help in immobilizing the affected part at an earlier stage, thereby reducing the recovery time for patients. [ABSTRACT FROM AUTHOR]

A novel reconfigurable 3-D frequency selective surface (FSS) exhibiting bandstop response is proposed in this paper. The unit cell of the proposed 3-D FSS is constructed from concentric threaded cylinders. The proposed novel 3-D FSS achieves reconfigurability by sliding technique. It offers frequency tuning from 1.86 to 3.10 GHz by sliding the outer cylinder over the inner cylinder. The proposed FSS offers bandstop response in the L- and S-band microwave frequencies. In addition, the proposed 3-D FSS provides polarization- and angular-independent operation. The prototype of the 3-D FSS is fabricated, and the simulation results are validated using measurements. [ABSTRACT FROM PUBLISHER]

This paper proposes a method for detection of cracks in bare printed circuit board sheets before etching of interconnects and mounting dies. A microwave planar sensor probe is designed, and the impedance matching property is used for anomaly detection in flame retardant-4 sheets. The proposed technique and apparatus is first validated through finite-integration-based technique and then through measurement. The resonant frequency information thus obtained is then plotted on a 2-D gradient representation matrix. A novel Windows VB-based application software is developed to determine the dimensions of the crack in the sample through various interpolation operations and dimensioning technique on the image matrix. These are then effectively displayed in a graphical user interface. [ABSTRACT FROM AUTHOR]