Efficient range oversampling processing on the National Weather Radar Testbed

Range oversampling techniques are a practical way to decrease weather radar update times without increasing estimation errors. One of these techniques, adaptive pseudowhitening, was implemented on the National Weather Radar Testbed (NWRT) during the 2010 spring season. Adaptive pseudowhitening utilizes different pseudowhitening matrices based on the estimated signal-to-noise ratio (SNR) and spectrum width at each range gate. This approach leads to better performance than a fixed transformation over widely varying conditions. On the NWRT, scan update times were reduced by roughly a factor of two without a noticeable increase in errors. At higher SNR values, there was even some improvement in data quality. This novel real-time implementation is computationally efficient and simplifies the utilization of different transformations for all of the basic spectral moments. With the forthcoming dual polarization upgrade to the Next Generation Radar (NEXRAD) system, this novel implementation could also be extended to dual polarization variables. An overview of this real-time implementation will be presented along with some practical suggestions for SNR censoring.