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Every antenna is at resonance according to length to which it is cut ! They are usually cut to resonate at a particular band of frequencies, ie, Vhf Television band etc.
If no resonance then no signal is present and in such a case antenna is merely a random chunk of metal.
The magnetic field that an antenna puts out will produce an electric current on any conducting surface that it strikes, however if that surface has a characteristic length the induced current will be much stronger on the object. For example, when a Citizens Band signal travels through the air, it completes a cycle in approximately 36 feet. If the object that the magnetic wave strikes is 18 feet long (1/2 wave length), 9 feet long (1/4 wavelength) or 36 feet long (1 full wavelength), then the induced current will be much higher than if the signal struck a metal object that was not some appreciable fraction of the wavelength of the signal.
A resonant antenna is so much more efficient at converting (receiving or transmitting) current between the field and the antenna's feed-point than a non-resonant antenna that much effort is put into configuring resonance. A non-resonant antenna still works as an antenna but simply requires a more sensitive receiver or more powerful transmitter.
If you have ever heard people say they want to "tune" their antenna, they usually mean they mechanically change lengths in relation to the frequency / wavelength they are trying to match. It is also possible to change electrical properties to match frequency, which is more handy for matching multiple frequencies with a single antenna.
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Difference between gsm antenna and microwave antenna?
In GSM mainly using Panel type antennas but in the case of Microwave Antenna using Horn antennas. Microwave anteenas propogate signal straghtly. So line of sight (LOS) is main issue in the case of Microwave antenna, it means that both antennas must be allign in face to face. Microwave antennas are using for link between BTS but GSM antennas are directly link with customers. Antenna Gain also very much difference both cases. JPS o,[.[;.;[.]/]/ pppppppppppppppp
Why does a series resonant circuit cannot be tank circuit?
A series resonant circuit has it's reactive components connected in series with each other; while the reactive components, as in a "tank" circuit, are connected in parallel with each other. The resonant series circuit has the capability of producing usable increased voltage levels across each component at resonance, while the resonant tank circuit does not. The resonant parallel, or "tank" circuit; has the dual capability of creating a situation whereby the input amperage level is reduced to minimum while, at the same time, a maximum amount of circulating amperage is created between the two reactive tank components at resonance.
What is an antenna and what is the difference between an omni antenna and a panel antenna?
"What is an antenna": the antenna is a device that couples electromagnetic fields between free space and a circuit (radio, cell phone, etc.).An omni or omni-directional antennais one that works equally well in all directions. Real antennas can only approximate this to a greater or lesser degree. In most applications, but not all, when someone says "omni antenna" they mean it works the same as you go around the antenna in azimuth.The shape of a "typical" simple donut explains this very nicely. Going around the round edge of the donut, it is the same in all directions. But if you go up from the edge to the top of the donut, its shape changes. It's the same with a simple omni antenna. If you have one on your desk as a wireless access point and you walk around the antenna at the same distance, it will work just the same at every point in your walk. If you climbed up a ladder, though, then as you go up the ladder you will be going towards the top of the donut and how the antenna works will change.A panel antenna is made very differently from an omni-directional antenna. It works a bit like a flash light, focusing all the energy in one direction. If you had a flash light sticking out from the front of a panel antenna, you'd see it stick out a lot in the front and only a little to the sides and up/down. Likewise, the panel antenna works mostly straight in front and only a little to the sides and up/down.
What is an antenna?
In Electomagnetics, Radio, Electronics, etc.:An antenna is a structure that couples energy between a circuit (radio, cell phone, etc.) and free space. The plural is antennas.In Biology, Zoology, etc.:An antenna is an organ used to sense the surroundings. The plural is antennae.
What is the difference between detector and diode detector?
difference between detector and diode
What is the difference between transmitting and receiving antenna?
There is no difference between the two.
Difference between hertz antenna and marconi antenna?
Hertz Antenna is lambda by 2 antenna & marconi antenna is lambda by 4 antenna...
What is the difference between an active antenna and a standard antenna?
An active antenna has a amplifier built in, a standard antenna does not. AKA powered antenna.
What is the difference between an ordinary transformer and resonant coupling energy transfer?
An ordinary transformer uses mutual inductance to transfer energy from one circuit to another, while resonant coupling energy transfer utilizes resonance between the coils to enable more efficient energy transfer. Resonant coupling allows for wireless power transfer over larger distances compared to traditional transformers.
What is the difference between resonance and resonant frequency?
resonance is the behavior of resonant frequency while resonant frequency is the cause of it. There are basically two types of resonance; Electrical and Magnetic. Resonant frequency is that particular frequency for a system for which the system performs its best. while the system at that particular situation can be called the system at resonance
What is the difference between directed antenna and parabolic dish?
about 40 db about 40 db
How do you tell the difference between a boy and a girl mealworm?
If it has antenna that stick up it is a boy and if it has antenna that stick out it is a girl.
What is relation between grasshopper and antenna?
There is no scientific link between grasshoppers and antenna except for the fact that grasshopper have two antenna
Difference between gsm antenna and microwave antenna?
In GSM mainly using Panel type antennas but in the case of Microwave Antenna using Horn antennas. Microwave anteenas propogate signal straghtly. So line of sight (LOS) is main issue in the case of Microwave antenna, it means that both antennas must be allign in face to face. Microwave antennas are using for link between BTS but GSM antennas are directly link with customers. Antenna Gain also very much difference both cases. JPS o,[.[;.;[.]/]/ pppppppppppppppp
What do you understand by bandwidth of a parallel resonant circuits?
The bandwidth of a resonant circuit is defined as the distance between the two -3dB rolloff points in the response curve.
What is the difference between simo and mimo?
In SIMO TX is simple with one antenna and in MIMO N antennas in TX so complex
What is the difference between an omnidirectional and an isotropic antenna?
An isotropic antenna is a theoretical point source that radiates equally in all directions, but it does not exist in reality. Omnidirectional antennas, on the other hand, are practical antennas that radiate in all directions but may have variations in their radiation patterns. In essence, an omnidirectional antenna approximates the radiation characteristics of an isotropic antenna.
