Radar sensor failure

[dpavid]

What might be some reasons why an radar antennae or sensor fails to give out true infomation?

not things that can go wrong with hardware but what aspects of the outside world can interfere with normal operation?

We're building a rover that can use a sensor to pickup its surroundings but want to be sure that it can work in all places.

Thankyou!

[johnnygoode1]

I just posted a similar question here a few days ago about failure modes of a radar sensor. We had already looked at RF noise, ghost targets, and obscurants on the sensor but I'm sure other modes exist. What about an antenna that sort of radiates in a pattern that can't be reflected by the environment?

[TheUnnamedNewbie]

Antenna grating lobes can be an interesting thing.

[radar_macgyver]

Multipath (also called three-body scatter) - the beam undergoes specular reflection off one target, illuminates a second, then the energy makes the return trip. Causes additional targets to appear at further range from a strong one.

Sidelobe illumination - you pick up a strong target that's not where your antenna's pointed because it falls in the sidelobe of the antenna's pattern

Attenuation - absorption of transmitted energy by the medium or by the object being detected

Anomalous propagation - caused by refractive index changes in the atmosphere causing the beam to bend towards the ground (probably not an issue for small radar systems)


What sensor are you using? That has a huge impact on the kinds of imperfections you can expect.

[wmcdonald1]

If the installation angle of the radar is imperfect you could get bad readings but I think the doppler effect would take care of that.

[johnnygoode1]

If it's anything like the one I was looking at it's a small automotive radar sensor with a range of about 200 meters.