In this report, we use pencil-beam Doppler weather radar data, combined with on-airport ground clutter measurements, to analyze the performance of the six-level weather channel in the next generation airport surveillance radar, the ASR-9. A key tool was a computer procedure that used these data to simulate the output of the ASR-9s weather channel, including effects of the radars fan-shaped elevation beams, short coherent processing intervals and ground clutter filters. Our initial analysis indicates that a the combination of high-pass Doppler filters and spatialtemporal smoothing should normally prevent ground clutter from having a significant effect on the controllers weather display b the spatialtemporal smoothing processor will result in weather contours that are statistically stable on a to-scan basis, reinforcing controller confidence in the validity of the data c relative to the coarse resolution imposed by use of the NWS levels, accurate two-dimensional parameterizations of storm reflectivity can be estimated. Our assessment indicates that the ASR-9s weather reflectivity maps should be reliable. The radar will be widely deployed at significant air terminals, and will provide a combination of high update rate and large volumetric coverage not available from other sensors. These attributes should lead the ASR-9 becoming an important component of the Federal Aviation Agencys modernized weather nowcasting system.
Original contains color plates: All DTIC and NTIS reproductions will be in black and white.