MICROWAVE AND OPTICAL TECHNOLOGY LETTERS

IoT enabled smart bus for COVID-19
Anandkumar A, Dinakaran K and Mani T
The main objective of this project is to ensure the safety precautions in public transportation. This project monitors and stores the database of number of allowed users with their respective temperature. The person's identity is monitored with the help of radio frequency identification (RFID) tags. The sensors and RFID reader are interfaced with the Arduino. If the temperature is increased then the threshold level alert message is passed to the person personal mobile through global system of mobile communication and the bus door does not get opened. Then if any fire, breakdown and accident exist it sends intimation to the nearby hospitals and fire service via the control room. The current location of the bus is known by using global positioning system. The entire module information controlled by IoT and the data are stored in cloud server. This system also can be implemented in theaters\shopping malls to monitor the number of allowed persons with their respective temperature as per government instructions.
Heterogeneous Anthropomorphic Phantoms with Realistic Dielectric Properties for Microwave Breast Imaging Experiments
Mashal A, Gao F and Hagness SC
We present a technique for fabricating realistic breast phantoms for microwave imaging experiments. Using oil-in-gelatin dispersions that mimic breast tissue dielectric properties at microwave frequencies, we constructed four heterogeneous phantoms spanning the full range of volumetric breast densities. We performed CT scans and dielectric properties measurements to characterize each phantom.
TUNABLE RING LASER BASED ON A SEMICONDUCTOR OPTICAL AMPLIFIER AT 1300 NM USING A SIMPLE WAVELENGTH SELECTION FILTER
Jeon M, Kim J, Song JW, Lee H, Choi S and Nelson JS
A simple, compact, and low cost tunable ring laser with a commercial semiconductor optical amplifier (SOA) was demonstrated. The tunable ring laser is based on an external wavelength filter cavity that is analogous with the Littman configuration with a diffraction grating, a mirror, and a simple slit. The unique structural advantage of this new system is that the slit is displaced to select a desired wavelength instead of tilting the mirror as in the Littman configuration. This allows easy control over the selected wavelength by the translating action of the slit. The full width half maximum (FWHM) wavelength turning range is 45 nm, and the wavelength resolution is about 2 pm. The demonstrated tunable ring laser has 2 mW output power. The side mode suppression ratios is 70-73 dB.