Tethered Aerostat RADAR System (TARS)
449-MHz RADAR Wind Profiler Project
Radar Wind Profilers (RWP's) have been used for years for weather forecasting, pollution studies, and even to support rocket launches. A new need is now being addressed through funds provided by the Air Force, to support the Tethered Aerostat Radar System (TARS).
The Tethered Aerostat Radar System is a balloon-borne radar. The primary aerostat mission is to provide radar data in support of federal agencies involved in the nation's drug interdiction program. Currently there are 11 sites placed across the southern United States, from the west to the east coast. These aerostats "fly" while being tethered to the ground, and continually scan the horizon tracking airplanes.
Operational concerns for these aerostats include severe weather (affecting its ability to stay aloft) and safety (both in the air and when retrieving the aerostat). RWPs are being installed at the TARS sites by ESRL/PSL to provide crucial information about winds aloft to aid the aerostat operations. The first TARS site with this system was Ft. Huachuca, Arizona; the second was near Key West, Florida. These new RWP sites will also augment the established NOAA network of wind profilers across the central U.S. to support weather forecasting operations. The new 449-MHz RWP is designed to provide 15 min average winds (updated every 5 mins) from 0.15 to 4.0 km above the ground with 0.12 km vertical resolution and run continuously with little operator intervention. The systems consist primarily of commercial-off-the-shelf (COTS) parts and will be integrated and tested at the Boulder Atmospheric Observatory near Boulder, Colorado.
One non-COTS part is the NOAA Radar Wind Profiler Advance Signal Processing System (SPS) modules. The SPS modules operate on a separate computer and handle all data processing from the spectral level on up. The SPS performs multiple spectral peak picking and identification, time- height continuity checks, and provides a "confidence" value for each calculated wind point. This confidence value can be set to screen out virtually all contaminated wind data.
The following are plots of processed data and digital pictures of the system in various stages of integration. The wind barb pictures show calculated wind profiles for different time averages, and for comparison, normal Consensus averaging as generated by LAPXM(TM).