Electrical Engineering Stack Exchange
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Questions tagged [radar]

Anything related to RADAR (RAdio Detection And Ranging) systems, their operations and circuits. RADAR systems are used to detect and locate a target by sweeping a beam of microwaves across a region of space and detecting echo signals reflected by the target.

Anything related to RADAR (RAdio Detection And Ranging) systems, their operations and circuits.

RADAR systems are used to discover and locate an object by sweeping a beam of microwaves across a region of space and detecting the echo signals reflected by the object itself.

See also Wikipedia on RADAR.

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Will radar/lidar still work when every car is equipped with them?

Self driving cars rely on cameras, radar, and lidar to recognize the environment around them. Cameras of course don't interfere with each other, since they are passive sensors. Since a signal received directly from another transmitter is much…
crj11
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How did old WW2-era radars accurately measure time delay and integrate this into an oscilloscope?

The speed of light is about 300,000 km per second. An error of just 1 ms would result in being off by about 300 km, which is far too much error for a radar. I would guess it needs accuracy on the order of 10 microseconds in order to get range…
DrZ214
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How does LIDAR avoid getting confused in an environment being scanned by hundreds of other LIDAR?

(Meta: I do not know an appropriate place for this on Stack Exchange. There does not appear to be any groups related to autonomous driving technology and computer 3D vision / perception systems.) For self driving vehicles using 3D depth perception…
Dale Mahalko
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Why are sound waves the best choice for many location detectors?

I'm currently working on my high school final project, which is basically a radar. I'm using the SRF05 detector to detect objects that are near the surface of the device. My current assignment is to learn and summarize all the different components…
Eminem
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What power limitations was chirped radar designed to overcome?

Chirped Pulse Amplification (CPA) is an optics technique, winner of the 2018 Nobel Prize in physics, which is used for producing short laser pulses at intensities which are high enough that the gain medium would destroy itself through nonlinear…
E.P.
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Can I improve the directivity of an X-band radar module with integrated plane-patch antenna?

Lots of detail provided in case it's needed. I'm continuing to tinker with remote proximity sensors driven by an Arduino (and eventually just an ATMEGA* chip and its safety buddies) and have a pretty good prototype so far. It picks up motion just…
Joshua Nozzi
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How does / can this radar wave detector circuit work?

I have difficulties to understand how the below circuit can detect radar waves by only using C1 and the lengths of its wires to IC1. Can this work? And if yes, how? What is the physics theory behind this? This circuit uses a 1458 dual op-amp to…
arminb
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Why do the Duga-1 dipoles look like an array of birdcages?

Looking for sources for the question What Soviet signals attempted to scramble communication and sabotage Apollo missions? I ran across the Wikipedia article for Duga Radar. Below are cropped and rotated bits from the images in the article. The BBC…
uhoh
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Uniform Linear Array (ULA) beamwidth and angular resolution using FFT

I have a four element uniform linear array receiver and I want to know what will be the angular resolution if I perform perform Fast Fourier Transform (FFT) over antenna elements. As I think that it will be same as the beam width of the array. The…
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Help reverse engineering RCWL-0516 microwave proximity detector module

I got a cheap RCWL-0516 microwave doppler radar proximity sensor module to evaluate. The RF part of this has surprisingly few components (what looks like a MMBR941M NPN and a hand full of passives)... but I think more important is the microwave…
jdesbonnet
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Radar received RF signal phase-shifted by 90 to obtain I/Q signals

I am trying to get idea how marine radar works before start any repairing process. And this part confused me, most articles that i saw explain that in mixing stage we obtain I/Q signals using LO signal and as well LO shifted by 90 degree, but…
Tremax
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Does this VCO produce a sine wave or square wave

I'm looking at the datasheet for the analog devices hmc431lp4 voltage controlled oscillator, and I can't tell if its output waveform is a sine wave or square wave. The datasheet doesn't label the oscillator as being harmonic or relaxation. I'm…
Saunders
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24GHz Radar : IF amplification and strange mixer output

I am currently working on a project where I have to study a microwave Doppler Radar. Here are some details so that you can better understand it : a local oscillator (LO) at 24GHz is linked to an emitter antenna. A moving target reflects back the…
C_Computing
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Why does medical ultrasound use pulses instead of chirps?

My background is in radar where it's quite common to use chirped excitation signals (i.e. pulse compression). I have noticed that this method seems to not be used in medical ultrasound. Why not?
Colin Marcus
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IC / logo identification: 5.8 GHz radar MMIC marked "5810"

Can anyone identify the pictured IC or the manufacturer logo on it? It's a 5.8 GHz radar MMIC with 1 Tx, 1 Rx, PLL, power amplifier, mixer, and low noise amplifier, presumably from an Asian semiconductor company. It's in a 3x3 mm QFN package with 20…
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