Improved Range-Velocity Ambiguity Mitigation for the Terminal Doppler Weather Radar

Range and velocity ambiguities pose significant data quality challenges for the FAA's Terminal Doppler Weather Radar (TDWR). A major upgrade is currently being developed for the radar data acquisition (RDA) system of the TDWR. With the anticipated enhanced signal processing and waveform specification capabilities, there is an opportunity to improve the range-velocity (RV) ambiguity mitigation scheme as well. We propose using a combination of pulse phase-code processing and multiple pulse repetition interval (multi-PRI) waveform processing for first-trip protection and velocity dealiasing. Because these two RV ambiguity mitigation methods are complementary in range-fold protection capability, an adaptive selection algorithm that uses a preceding long-PRI scan for complete unambiguous range coverage will determine the optimal waveform/processing choice on a radial-by-radial basis. We present results using both simulated and real weather data, which reveal dramatic improvements in RV ambiguity mitigation over the current operational approach.

*This work was sponsored by the Federal Aviation Administration under Air Force Contract No. F19628-00-C-0002. Opinions, interpretations, conclusions, and recommendations are those of the authors and are not necessarily endorsed by the U.S. Government.