Questions tagged [radar]
The radar tag has no usage guidance.
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Continuity of a quantity in a conical system to determine the velocity field
My research is on radar images and the images are collected in several conical surfaces. These conical surfaces have the same origin, the same maximum length (max flare or max range), but different ...
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Second-order variation of an integral
I was reading the paper SISAR Imaging for Space Debris based on Nanosatellites, in which the Fresnel-Kirchoff diffraction formula is applied for a scenario in which the receiver, transmitter and ...
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Is it possible to build a radar that is shielded behind one meter of ceramic material and still detect people 500 meters away? [closed]
I saw that there are radars which can detect people behind walls so I wonder what are the limitations of radars when it comes to detecting people behind solid objects and if radars can have thick ...
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Aliasing in Pulse Wave Doppler/Radar
There are many pictures on the Internet showing sampling of the output wave and then showing the phenomenon of aliasing, e.g.:
But on the other hand, I find information that in the pulse (Pulse Wave ...
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What are the reflective properties for 77 GHz electromagnetic waves (automotive RADAR)?
Automotive radar uses electromagnetic waves around 77 GHz frequency. Is there some data, tables available about the reflectivity of such waves for various materials, like water, stone, people, metal ...
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Why does radar have a much longer range than infrared sensors? (in the context of military aircraft)
In the context of military aircraft and missiles, radars often have ranges of hundreds of kilometers, while thermal infrared sensors can only barely reach 100 km in the best of circumstances. But ...
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Avoiding radar detection using active noise control instead of a stealth fuselage
was reading about different stealth technologies used by modern aircrafts to avoid radar detection.
Wouldn't it be easier to have a receiver on the airplane listening on the radar frequencies and then ...
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Is it possible for a pulse doppler radar(full coherent) to integrate multiple pulse with different carrier frequencies (during an integration)?
Especially for digital (modern) radar?
Also is it possible (in the same configuration to integrate multiple pulses with the same carrier frequency with intrapulse modulation (each pulse has a ...
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How to calculate relative permittivity from the following chart
So basically, I was using HFSS to run some simulation on a MnZn absorber https://www.researchgate.net/figure/a-Real-and-b-imaginary-dielectric-permittivity-curves-for-RAM-based-on-MnZn-...
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Single-Antenna-Single-Pass SAR interferometry
As I understand, for elevation mapping using InSAR, one typically requires an out-of-plane baseline to create the required phase difference between images to detect objects at height. This usually ...
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What is the explanation that the same material could receives and reflects EM wave signal while another absorbs?
Here is B-2 Spirit, a stealth bomber by Northrop Grumman. Another one is a depiction of a parabolic dish antenna receiver. As we knew, the B-2 is a stealth aircraft, which is not reflects the received ...
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LIDAR vs. RADAR
Our TV news today said the cops have switched from radar to lidar because it is more accurate in fog. But isn't light absorbed by fog more than radar frequencies?
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Can low lying clouds increase the distance of the radar reach from 18 to 120 km?
I have seen an article (sorry its Russian) claiming that low lying clouds have increased the distance of the radar reach from the normal 18 km till as far as 120 km. This allowed the military ship to ...
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Time difference of arrival between radar pulses
Consider the following geometry:
Where $\bar{s} = (s_x,s_y)$ is an object of interest, and $\bar{r_c}$ is the location of the radar.
Let the echo delay time of a radar pulse to the scene center be $...
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How distance is determined between two inertial frames in empty space using Bondi’s radar method?
I have read how Bondi’s radar method can be used between two vessels in empty space to determine their relative distance and also if their distance is increasing or decreasing.
Can Bondi's radar ...
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