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Calibration of Speed Enforcement Down-the-Road Radars



John R. Jendzurski, Nicholas G. Paulter Jr.


We examine the measurement uncertainty associated with different methods of calibrating the ubiquitous down-the-road (DTR) radar used in speed enforcement. These calibration methods include the use of audio frequency sources, tuning forks, a fifth wheel attached to the rear of the vehicle with the radar unit, and the speedometer of the vehicle. We also provide an analysis showing the effect of calibration uncertainty on DTR-radar speed measurement uncertainty.
Journal of Research (NIST JRES) - 0415
Report Number


dtr radar, police radar, radar calibration, speedometer, tire, tuning fork, uncertainty


Jendzurski, J. and Paulter, N. (2009), Calibration of Speed Enforcement Down-the-Road Radars, Journal of Research (NIST JRES), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed May 22, 2024)


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Created May 1, 2009, Updated November 10, 2018