Why is it difficult to detect static objects using a 24 GHz RADAR system in cars particularly at high speeds ? static objects could be a stationary vehicle, a police barrier, a animal on the road or a dead end like a wall or tree etc... It is easier to detect a moving vehicle than the static object. Why is that so ? Considering both moving and stationary object will reflect back RADAR pulses. The RADAR system is a Front Collision Warning System installed in the front of the car.
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because the road and traffic signs are static as well – Marko Buršič May 26 '16 at 09:34
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Is it? Says who? Is it because the objects are radar-transparent? – pjc50 May 26 '16 at 09:39
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Static relative to what? – Roger Rowland May 26 '16 at 10:16
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Static relative to the car of course – user974168 May 26 '16 at 10:58
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3None of your examples are static relative to the car, unless the car is not moving. – Roger Rowland May 26 '16 at 11:07
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Useful search term : "doppler". – May 26 '16 at 11:18
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To categorize static objects having no Doppler shift, a radar system would need the resolution and image processing capabilities approaching those of a vision system. – Chris Stratton May 26 '16 at 14:54
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It is because of ground clutter. Car manufacturers use Doppler radar. Doppler radar utilizes the Doppler effect to help the radar to distinguish objects that are close together.
You can see how the moving object has different frequency and can be distinguished from the terrain even though the range return is identical. The problem with stationary objects is that they have the same Doppler shift as the earth, trees, signs etc. The radar cannot distinguish between a dead animal and the road.
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