All Questions
6
questions
15
votes
7
answers
2k
views
Why does the length of an antenna matter when electromagnetic waves propagate perpendicular to the antenna?
The optimum length for a dipole antenna is a multiple of half the wavelength that it is designed to receive or emit. Why is this? If an electromagnetic wave has E in the x-axis, B in the y-axis, and ...
- 161
1
vote
1
answer
63
views
If the speed of light is a constant value and the wavelength is constant (antenna), how can one antenna transit/receive different frequencies?
The speed of light is about 300,000,000 m/s, and the wavelength is determined by the design of the antenna, how can one antenna transmit different frequencies other than just the one defined by
f = c /...
- 13
0
votes
1
answer
679
views
How to explain mobile phone rings inside microwave oven? [duplicate]
So finally tested myself and found: mobile phone rings inside microwave oven.
Microwave oven frequency is 2.5 GHz which gives wavelength of 12 centimeters. Cellular network waves are even longer. Thay ...
- 1,732
3
votes
1
answer
2k
views
Does grounded sheet metal reflect or absorb radio waves?
By "radio waves" I mean waves used for radio transmission appliances, e. g. within 1 MHz to 10 GHz.
If the size of the metal sheet makes a difference, please answer for a infinite sheet and a fridge.
...
1
vote
1
answer
884
views
Radio waves collision versus waves in a pond collision
Please see the attached picture:
We are trying to show an image to visualize radio wave collision and interference with regards to Maritime AIS Technology. What do colliding radio waves have in ...
- 281
33
votes
7
answers
23k
views
Radio antennas that are much shorter than the wavelength
From my limited experience with ham radio when I was a kid, I expect transmitting and receiving antennas to have lengths that are on the same order of magnitude as the wavelength, and in fact I recall ...
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