The tag has no usage guidance.

learn more… | top users | synonyms

0
votes
1answer
20 views

What exactly is an “instrumentation radar”? [closed]

I am coming across this term "instrumentation radar" without exactly defining it but with adjectives like high performance, mono pulse etc. But what exactly is an instrumentation radar?
-1
votes
0answers
35 views

How was light used to detect targets in pre-radar times? [closed]

I read that light (optical systems) was used to detect targets in the air and sea before radar was used. I saw photos of light being focused in the skies etc. But I want to know more about this - How ...
5
votes
0answers
64 views

What happens to a radar signal when it meets with a superconductor? [duplicate]

A radar system has a transmitter that emits radio waves called a radar signal, consisting of electromagnetic radiation. What happens when it meets with a strong superconductor, considering the fact ...
0
votes
0answers
10 views

How does Dual-polariasation weather radar detect raindrops that have a larger H to V ratio

I was reading this document on dual polarisation weather radar - http://www.wdtb.noaa.gov/courses/dualpol/documents/DualPolRadarPrinciples.pdf and looking at how this can be used to detect when water ...
2
votes
0answers
36 views

Wavelength, frequency, and radars [closed]

I'm doing a high school paper on the effects of frequency alterations on a radar image. Can someone recommend a book which I can use?
0
votes
3answers
156 views

How do radar speed signs work?

Everyday when I'm going back home from college, I pass by this big radar speed sign and I've noticed that it does a peculiar thing. The sign is placed on a downward slope of the street. So say I'm ...
8
votes
1answer
173 views

Is radar-style 'pulse coding' (stretch, amplify, interact, and then compress) used in the optical domain?

Chirped Pulse Amplification (CPA) is an optics technique for producing short laser pulses at intensities which are high enough that the gain medium would destroy itself through nonlinear phenomena ...
0
votes
2answers
89 views

Does radar affect magnetism?

Does radar affect magnetism? Let's say I have two magnets, one is suspending the other. Would radar affect the magnetic field?
0
votes
2answers
112 views

Why can't LIDAR be implemented with traditional antennae?

In robotics, LIDAR and RADAR are both used for obstacle detection. The data they produce are very similar, but they do have different qualities (LIDAR is more precise but less robust). There are many ...
0
votes
0answers
89 views

Looking for full equation for radar cross section of corner reflector

There's a well-known formula for the RCS of a corner reflector (aka corner cube), to wit $ \sigma \varpropto \frac{L^4}{\lambda^2} $ . I've found several sources which cheerfully say "...valid for $ ...
0
votes
1answer
169 views

Why would a sweeping LIDAR or RADAR beam not produce an artificial Doppler shift?

Assuming a bi-static Radar or LIDAR with a stationary transmitter and a stationary target and a stationary receiver, with a sweeping RADAR/LIDAR beam reflecting off a stationary target: Why would the ...
1
vote
2answers
96 views

Radars on Space Ships

If a radar (say, an x-band radar similar in size to that of a modern fighter aircraft) was carried by a spaceship, would the radar have a greater range in vacuum of space than it has in atmosphere?
0
votes
1answer
991 views

Simple explanation of Coherent integration radar

I have a physics background, and I'm reading some physics data analysis papers where they keep throwing around the term coherent integration. I've done the google search, but the best answer I could ...
0
votes
2answers
88 views

Chaff-RF Relationship?

What is the relationship between chaff length and the frequency it is meant to interfere with? I've read that specific lengths of chaff are more effective as a countermeasure for specific frequencies,...
0
votes
0answers
187 views

Radar Vs. Sonar

What is the true difference between radar and sonar? My understanding is that radar uses a reflected EM wave, while sonar uses a compression (shock wave) of the material it's in. (It compresses water, ...
1
vote
3answers
2k views

Do radio waves interact with electrical wiring?

AFAIK radio waves can be influenced by magnetic fields (when not traveling through a vacuum). Electrical wires create a magnetic field perpendicular to the length of the wire, as a function of the ...
1
vote
0answers
19 views

Conjugated-Phase Matching

I am working on imaging applications of phase-conjugation in optics, in particular phase-conjugation imaging from recorded holograms. I have found several useful sources, but I cannot find a book ...
0
votes
0answers
127 views

Radar as range detector between cars-static sender vs dynamic sender

Say I have a radar transmitter on a car,used to detect its distance from a car in front of it by measuring the doppler shift on the reflected wave. i.e Car 1 is the source, its wave gets reflected by ...
17
votes
2answers
7k views

How do they measure the rotational speed of cricket balls?

The 2013 Ashes series (a cricket thing between England and Australia) are underway as of today and it seems they have a new (to me) gimmick. It appears that they are now able to measure almost ...
1
vote
2answers
330 views

Scale-down modeling for radar cross-section measurement

Scale-down models for targets are used for radar cross-section measurements of huge-size objects. Is there any upper limit to the scaling factor on downscale modeling as a $100~\text{m}$ length of ...
4
votes
1answer
803 views

Does weather obstruct microwaves and radiowaves?

I read an article ('How airplanes use radar' at Bright Hub.com) that stated that airplanes use radio waves for communication because they aren't obstructed by weather. Is this true?
0
votes
1answer
172 views

Can natural predators detect human stealth technology?

Just a thought experiment since bats are probably not swift enough to take evasive action in the scenario described. If a cloud of bats were to encounter a B-2, or F-35, or F-117 or any of the other ...