Isaac was born in Kahalu‘u on the island of O‘ahu. He attended UH Hilo to complete his pre- engineering courses, then transferred to the UH M?noa, where he is currently a senior in Electrical Engineering with an emphasis in Electrophysics. After he graduates in Spring 2014, he plans to pursue a PhD in radio-frequency (RF) engineering.
Home Island: Oahu
Institute when accepted: UH Manoa
Development of Baseline Measurements and
a Routine Testing System for TBAD using TSIM
Project Site: W.M. Keck Observatory
Mentors: Randy Campbell & Luca Rizzi
The W.M. Keck Observatory uses a 20-W laser to excite a sodium layer in the upper atmosphere, in order to create an artificial guide star for its adaptive optics system. This laser can potentially damage the vision of airplane pilots, or be a source of confusion for them. Because of this, the laser must be shuttered whenever an aircraft enters laser-affected airspace. The current detection method is to station human personnel outside the observatory to watch for aircraft by eye. To assist with this manual method (and eventually replace it, once fully tested and approved), Keck has acquired a new Transponder-Based Aircraft Detector (TBAD) system: since it is expected that virtually all aircraft will use a transponder that sends out a signal, or “squawk,” for purposes of guidance and navigation, TBAD uses a patch-array antenna to acquire these signals and automatically shutter the laser beam when the aircraft enters potentially dangerous airspace. A log is generated by TBAD of relevant data, such as shutter state, time, telescope position, and squawk code. A TBAD simulator, TSIM, was created to test TBAD — the simulator generates a signal much like the ones generated by an aircraft, and can be used to test various aspects of TBAD’s capabilities. We created a program to analyze the data received by TBAD during TSIM transmission. The data could then be used to develop baseline measurements that could be compared to routine testing data. A Python program was written to extract such information as minimum power detectable, beam width, and off-axis angles. The program’s graphical output includes plots of variables such as signal strength vs. off-axis angle. Once TBAD is approved, Keck will be able to rely solely on TBAD as its main aircraft protection, and TSIM will be used to routinely test TBAD against baseline measurements.