High power amplifier design for a new 449 MHz wind profiler radar [presentation]
Lindseth, B., Brown, W., Cohn, S. A., Jordan, J. R., Hock, T., … Lopez, N. (2010). High power amplifier design for a new 449 MHz wind profiler radar [presentation]. In National Radio Science Meeting 2010. Boulder, CO, US.
The National Center for Atmospheric Research (NCAR) deploys 915 MHz wind profilers, primarily for probing the boundary layer and precipitation studies. We aim to extend our profiling range and capability using a new 449 MHz modular design that also provides more flexible deployment options. We ha... Show moreThe National Center for Atmospheric Research (NCAR) deploys 915 MHz wind profilers, primarily for probing the boundary layer and precipitation studies. We aim to extend our profiling range and capability using a new 449 MHz modular design that also provides more flexible deployment options. We have explored system improvements including the use of amplifiers in an active array. The focus of this work is on single transistor Class-E amplifiers with efficiency up to 80% and output power up to 45W. As an introduction to the Class-E mode, our first tests were on a 1W Triquint CLY5 amplifier. Next, we evaluated a Triquint AGR0945E LDMOS transistor in a Class-E amplifier configuration. The input and output match and bias tee circuits were designed in Agilent ADS and fabricated using Rogers 4350B substrate. The output match circuit uses a low output impedance to compensate for the high output capacitance of the device and an open circuit stub at the second harmonic. This amplifier was tested under CW operation with 40W of output power, as well as 10% duty cycle radar pulses with phase modulation. The AGR09045E transistor costs less than $50, and demonstrates the availability of power transistors for $1 per watt or less. These amplifiers can either be combined together in a single amplifier module or distributed in an array behind each patch antenna. High efficiency amplifiers have the benefit of less dissipated heat, which can result in higher reliability and less heat sink weight. These technologies will improve the portability and signal to noise ratio of the system, to provide an easily deployable high sensitivity radar wind profiler suitable for land or ship-based operations. Show less