This thesis investigates the performance of a phased array of antenna elements conforming to a paraboloidal surface. We hypothesize that such a conformal phased array would have performance comparable to that of a correspondingly sized planar array. The performance of a paraboloidal array of antenna elements was simulated using an array program, and the resulting gains, side-lobe levels, and half-power beamwidths compared to those of a similarly sized planar array. Furthermore, we propose a beam-forming feed network for this paraboloidal phased array, and discuss the influence that coupling between the elements could have on the array performance. Lastly, we propose that such an array be used in conjunction with a parabolic reflector antenna to form a versatile hybrid antenna with several potential applications. / Master of Science

This thesis investigates the design and the performance of low-power microsensors that communicate directly to a satellite or a constellation of satellites. Information is spread using pseudo noise (PN) or Barker codes. The sensors use a single circular microstrip patch element with a wide beamwidth or a miniature phased array antenna that continuously scans to access the satellite(s). The array beam is controlled with a beam-forming network (BFN), which contains 3 or 4-bit phase shifters, which can be made in micro-electro-mechanical systems (MEMS) or in monolithic microwave integrated circuits (MMIC). The antennas are designed using array simulation program called 'ARRAY' and the results are used in another simulation program called Advanced Design System (ADS) to simulate the whole sensor package that uses one of the antennas. The simulation results show that a sensor as small as 2.35 cm in diameter is able to send information with data rate of 1 kbps at bit error rate less than 10?? to low-earth orbit (LEO) satellites with a transmitted power of 27.5 microwatts (-15.6 dBm). / Master of Science