A 449-MHz wind profiler radar with low-cost 3 kW transmitter [presentation]
Lindseth, B. J., Brown, W. O. J., Jordan, J., Law, D., Martin, C. L., … Hock, T. F. (2012). A 449-MHz wind profiler radar with low-cost 3 kW transmitter [presentation]. In URSI National Radio Science Meeting. Boulder, CO, US.
The National Center for Atmospheric Research's (NCAR) Earth Observing Laboratory deploys sophisticated instruments and networks to support atmospheric research by university investigators. Among these are wind profiler radars and sounding systems, primarily for boundary layer and precipitation st... Show moreThe National Center for Atmospheric Research's (NCAR) Earth Observing Laboratory deploys sophisticated instruments and networks to support atmospheric research by university investigators. Among these are wind profiler radars and sounding systems, primarily for boundary layer and precipitation studies. In addition to our existing 915-MHz wind profilers, we have recently developed a prototype 449-MHz spaced antenna wind profiler radar. This wind profiler has a modular 54-element hexagonal antenna array that can be expanded to a larger array size and is designed to allow detection of winds at higher altitudes and with better time resolution than the 915-MHz systems. The spaced antenna technique that is used allows computation of horizontal winds from cross-correlation between receivers instead of Doppler shift of steered beams. Low-cost LDMOS 1-kW push-pull pulse amplifier modules are combined to form a 2.5-kW transmitter, with P3dB of 2640W, 63% average drain efficiency at 10% duty cycle, and gain of 15 dB. Coherent and spectral averaging provide detection of radar returns from clear-air Bragg scatter at signal levels of -150 dBm. The profiler is designed for 2-3 month deployments. A three hexagon/receiver version of the system was initially operated in Boulder and then deployed to the Persistent Cold-Air Pool Study (PCAPS) project in Salt Lake City, Utah during winter 2010-2011. Performance of the 449-MHz wind profiler was compared to radiosondes and a 915-MHz wind profiler at the same location. A seven hexagon/receiver system is currently being built and should be operational in late 2012. The higher transmit power and larger aperture will allow wind profiling through the boundary layer and up to 7 km. These systems will be available for deployment for land or ship-based projects. Show less