Dr. Gregory L. Charvat

WXR-150 Weather Radar Sidecar

Collins WXR-150 Weather Radar Sidecar

  • Long-range weather radar modification project based on a Collins WXR-150 weather radar set
  • 5.5 Kw, 5.5 uS, 96 Hz PRF, 9.36 GHz, X-band magnetron radar system with an envelope detector (according to the manuals)
  • Sidecar was developed to tap into an old WXR-150 to control the radar system by modern computer control and algorithms
  • LNA was added to the front end of the WXR-150 improving sensitivity (original design has only a mixer in the front end because X-band LNAs were VERY expensive in the 1970’s)
  • Sidecar interfaces with this radar system: A Low-Power Radar Imaging System
  • PRF reduced from 96 to 20 Hz
  • Integration now possible
  • LabView GUI user interface
  • PPI display of amplitude colormap
  • Logarithmic display
  • Automatic azimuth steering of the parabolic antenna
  • Manual electronic steering in elevation
  • Test target injection
  • Developed as part of a low-cost long-range radar learning experiment
  • Applications might include detecting of storm clouds out to 120 nmi (according to Collins specifications)

Summary

This is an experiment developed to understand long-range weather radar systems. The Collins WXR-150 is an airborne weather radar with a maximum range of 120 nmi. This radar uses a magnetron transmit tube with an analog automatic frequency control tuning receiver which sort-of phase locks onto the magnetron during each transmit pulse. It was decided to build a new back end that plugs into my Low Power Radar Imaging System project. A VI was written to control this radar. The radar front end was modified so that automatic gain control is disabled and is now manually controlled. The front end was also modified to include an LNA to improve the receiver performance. Taps were made in the envelope detector circuitry, outputting this data to the new back end. The transmitter is now triggered by an HP pulse generator. The data acquisition PC is also triggered off of this pulse generator.

Collins WXR-150 Weather Radar Sidecar Photos

Shown here are pictures of the Collins WXR-150 weather radar sidecar project.