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Re:Raspberry Pi Lidar Scanner by instagib on Saturday April 19, 2025 @10:21PM (#43741070)
Radar technology offers a range of applications, including the ability to detect objects around corners, behind obstacles such as brick walls, and even penetrate human bodies at specific frequencies. However, when multiple sensors yield similar results, it becomes challenging and costly to discriminate which results are valid.

Operating radar at a specific frequency, such as 2.45 GHz (a microwave frequency often used due to its affordability), can be ineffective in environments rich in water droplets (e.g., rain), as these can dominate the radar signals. Higher frequencies enable the detection of smaller water droplets, but switching between frequencies can be expensive. Additionally, varying the radar's detection range to identify objects of different sizes complicates the calculations, involving factors such as minimum and maximum range, power, and time on target.

Cameras typically detect non-moving objects by comparing successive images. In contrast, radar can identify both stationary and moving objects and determine their direction relative to the sensor by emitting a frequency and analyzing the reflected pulses. Lidar, on the other hand, uses light to measure the distance to objects in its path, employing a photoreceptor to capture the reflected light.

Re:Raspberry Pi Lidar Scanner by ndsipa_pomu on Sunday April 20, 2025 @06:21AM (#43742844)
That'll likely be why LIDAR is used rather than RADAR.
Re:Raspberry Pi Lidar Scanner by instagib on Sunday April 20, 2025 @06:53AM (#43742971)
I was responding to Tesla skipping Lidar but apparently it’s a sore topic. As pointed out by someone else Tesla used to use ultrasonic radar sensors but stopped.

“ Until this month's change, all Model S and Model X EVs intended for North America were equipped with radar sensors but the company has been building new Model 3 and Model Y vehicles without any front radar sensors since May 2021. That's when Tesla announced a change for those models away from radar to Tesla Vision” 0

I don’t think many people understand how these systems work but we’re not on a radar or engineering forum.

0. https://www.caranddriver.com/news/a39250157/tesla-no-radar-s...