I Can I send an electromagnetic wave to a specific point?

AI Thread Summary
Creating an electromagnetic signal in the 250 kHz to 500 kHz range and directing it to a specific point within 1 cm accuracy in a room is highly challenging. The signal will naturally propagate in all directions, making it difficult to achieve such precision with conventional antennas at these frequencies. Directional antennas are more effective at higher frequencies, but even then, achieving a narrow beamwidth is not feasible until reaching the hundreds of GHz range. The only viable solution for pinpoint accuracy would be to use a laser, as it can create a focused beam with minimal spread. Therefore, for the desired outcome, exploring optical methods rather than traditional electromagnetic waves is necessary.
nlopwer
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TL;DR Summary
I want to know if it is possible to make and send an electromagnetic wave to a specific point in a room.
Since I'm computer engineer and don't have much experiences with electromagnetism, I'd like to know if it is possible to make an electromagnetic signal (250khz - 500khz) and send it to a point (with an error of maximum 1cm) in a room. If yes which devices do I need to setup my experiment?
 
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Your problem is ill-defined. Do you want a single frequency? Do you want signal zero outside yourr 1cm?
Why don't you take a step back and describe what you are actually attempting to do.
 
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nlopwer said:
TL;DR Summary: I want to know if it is possible to make and send an electromagnetic wave to a specific point in a room.

Since I'm computer engineer and don't have much experiences with electromagnetism, I'd like to know if it is possible to make an electromagnetic signal (250khz - 500khz) and send it to a point (with an error of maximum 1cm) in a room. If yes which devices do I need to setup my experiment?

As Hutch said ... you problem is a bit il-defined
But going on what you have stated so far, the answer would be, no.
A signal somewhere in the range of 250 - 500 kHz, the radio/EM signal is going to
propagate out in many/all directions from the antenna ( depending on the style of antenna)
Making a direction antenna for such a low frequency would be near impossible.
The higher the frequency, the easier it is to make a signal directional, but even up into
the 10's of GHz, it's still going to be a very broad beamwidth over the distance of an average room
between the TX and RX. Really narrow beamwidth wouldn't really come into a usable possibility
till freq's in the 100's of GHz - THz range.

The ONLY way that it would be possible, off the top of my head aware of for such a narrow constraint in beamwidth, a cm or so would be a laser. Anything considerably lower in frequency than that of ""light"" IR, VIS or UV, via a collimating lens, is going to spread out and pretty much fill the room.

cheers
Dave
 
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It's rather like shining a light down a microscope to create a small spot. We can't make the spot much smaller than the wavelength, which in the present case is in the order of 1 km.
 
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