A compact, low-power, low-VHF radio for mobile and wireless communication applications

摘要

A cost-effective, low-power, ZigBee-based compact radio system tuned for operation at low VHF band is proposed for mobile communications in complex environments. Existing off-the-shelf radios at this band are bulky, usually operate at high power levels (a few watts), and require relatively large antennas to enable long range communications. To remedy these shortcomings, we develop a small-form-factor low-VHF radio that leverages the ZigBee technology with a frequency conversion technique. A bi-directional frequency converter for the radio is designed to translate ZigBee signals into low-VHF carriers and optimized to minimize power consumption, and simultaneously maximize system gain and sensitivity. This radio also comes with a newly developed miniaturized antenna [1] (≤ 0.02λ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</sub> in height and lateral dimensions at 40 MHz) having much higher efficiency compared to antennas of similar sizes. This antenna allows the compact radio system to operate at lower power and on small robotic platforms needed for military or rescue missions.