Phase locked loops find wide application in several modern applications mostly in advance communication and instrumentation systems. PLL being a mixed signal circuit involves design challenge at high frequency. This work analyses the design of a mixed signal phase locked loop for faster phase and frequency locking. The PLL is designed in GPDK090 library of CMOS 90nm process to operate at a freq...

Optically stimulated Lock-in thermography (OLT) which is an active thermography technique for NDT is based on propagation and reflection of thermal waves which are launched from the surface into the inspected component by absorption of modulated radiation. Phase angle images obtained by superposition of the initial thermal wave and its internal reflection display hidden thermal structures down ...

This paper explains the design and construction of a phase-sensitive near-field acoustic holography apparatus. By using phase-sensitive lock-in amplifier techniques to record the complex signals of pressure and particle velocity microphones over an extended spatial region, small vibrations can be imaged using the acoustical properties of said vibrations. The apparatus is tested on a vibrating d...

INTRODUCTION The current research was to investigate pilots' visual scan patterns in order to assess attention distribution during air-to-air maneuvers. METHODS A total of 30 qualified mission-ready fighter pilots participated in this research. Eye movement data were collected by a portable head-mounted eye-tracking device, combined with a jet fighter simulator. To complete the task, pilots h...