Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [antenna]

Antenna (radio), also known as an aerial, a transducer designed to transmit or receive electromagnetic (e.g. TV or radio) waves. -Wikipedia

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How does an antenna radiate (how do currents flow through the wire)

I don't understand how antennas radiate a signal. I understand the basics of antennas (wavelength, electron E field, etc.), but I simply don't understand how a current can go through a wire that doesn't have negative pole. Can you please explain…
depecheSoul
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Why are wifi antennas covered in plastic?

Couldn't it be like a radio antenna (wifi is radio after all), telescopic and without any encasing?
Quora Feans
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Directionality and gain: yagi versus parabolic antenna

I have a very remote cabin at 1000m (3000f), where I have close to no phone reception, so lately I have been trying to research as much as I can fathom of radio basics, but still without being able to conclude on anything with regards to what kind…
oligofren
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How does a receiving antenna generate current/voltage?

I have see on many websites people explaining how antennas radiates energy. But I am failed to find an explanation on how a receiver (i.e. receiving antenna) generates current/voltage? Can anyone explain?
Kumar
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motorcycles and vehicle ground loop detectors

I have been asked if it is feasible to make a motorcycle accessory that will trigger the traffic ground loop antenna sensors that typically fail to register the motorcycles presence. Reading up on these sensors, I find that they detect a vehicle by…
steverino
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How does having more antenna help in a networking router

When I look at networking routers on the market, those that provide external antenna connections offer at least 2 connections. What is the reason for having 2 antenna? Most if not all, have their antenna virtually at the same locality since they are…
Jake
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Antenna Identification

I believe the right most antenna is a mono-pole helical "rubber ducky" (please correct if wrong). But what type of antenna is on the left? It is terminated with a U.FL connector (not shown) and the center pin connects to a thin copper braid covered…
Mark B
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DIY Antenna Tuning

I know that getting a perfect tuning network for an antenna and transceiver requires some rather expensive equipment plus human knowledge to operate the equipment. I have never done any antenna tuning, but I would like to know if there is any way a…
Kellenjb
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What is the maximum and minimum of antenna gap of dipole antenna?

Consider the picture below is design of half wave length dipole antenna. I read some explanation that it is the best design to get the optimum transmit power. Or it is cut to 0.47Lamda to 0.48Lamda to get the optimum impedance (CMIIW). But my…
Sitorus
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How does a wire dipole antenna work when not straight?

I recently bought an FM antenna for a receiver like this. I've flattened it out a good bit on my windowsill but it's far from straight and is fairly wavy/curled from being bundled like this for who knows how long after manufacturing. How does this…
brenzo
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Chip antenna on breadboard

Is it possible to experiment with chip antennas on a breadboard? Any circuits available to let me do that? I am looking at this chip antenna, but any other is ok.
lyassa
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VHF Direction finding circuit

I want to take part in a direction finding exercise on 145.300 MHz FM. I have a 25-25 centre zero micro amp meter, which I intend to use to detect the direction of the FM carrier via an antenna. I am reasonably familiar with electronics but not…
William
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Monopoles on rooftops

During my commute every morning in the bus with nothing else to do, I have a strange tendency to notice antennas on the roofs of buildings. Almost every building has a Yagi, which I've been told is for TV reception. Another one which I see that…
S. Rotos
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Antenna to receive 50Hz

The human body seems to be a good antenna to pick up 50Hz, at least touching a scope's probe shows a 50Hz waveform more than a volt in amplitude. Is it possible to construct an electronic antenna that does the same thing? (Wavelength at 50Hz is…
Federico Russo
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How do the flat antennas pick up vhf signals?

The rabbit ear antenna had those two long poles for the VHF frequencies since those frequencies have pretty long wavelengths. The new flat antennas like mohu leaf and winegard don't have long wires in them. However they work extremely well based on…
SamFisher83
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