A radio antenna (or just aerial) is a transducer that can send and receive radio waves (electromagnetic waves) designed for radio, TV, cell phones, radar or satellite. A radio antenna is a transducer with a usable efficiency can perform one or both of these energy conversions: marketable alternating electrical energy for transmission of radio wave energy. Marketable radio wave energy to alternating electrical energy (military antennas).
Within the transmission we can define co-polar diagram that represents the communication from to a desired polarity and polarized radiation pattern with the opposite polarity to that you already have. The most important parameters of the radiation pattern are: pointing direction: The maximum radiation. Directivity and Gain. Main lobe constitutes angular range around the direction of maximum radiation. Side lobes are other relative maxima, lower the principal value.
A typical loop antenna is made of copper, in resonance with a variable capacitor when transmitting and can withstand high voltages. The transmission can take many amps and the voltage across the capacitor several kilovolts. Loops of copper are more effective than lower managers, due to the large flow. Loops are circular and more efficient than squares, an alternative is octagoner that are easier to manufacture.
Comparing an antenna yagi with a satellite, the antenna yagi have a F / B ratio of about 15 dB (depending on model and manufacturer) while for the parabolic relationship F / B is> 35dB (depending on model and manufacturer) . This is observed as "good" antenna on rejection of signals by the rear. The higher the paramentro in parabolic antennas will be better. The 15 dB of antenna yagui it can also be interpreted as the attenuation that would have on the system, if for example a bounced capture of a building, by the rear of the wave. Radiation resistance - when power is supplied to an aerial, radiating part of it and part is converted into heat dissipating. When talking about radiation resistance, it is made taking into account that cannot be measured directly.
If the antenna is replaced by the radiation resistance, this would do their job, ie, would produce the same amount of power that the antenna would radiate. The radiation resistance is equal to the ratio of the power radiated by the aerial divided by the square of the current in its feed point. One could obtain an mast efficiency, given that is the ratio of the radiated power and the dissipated power.
You can also define the beam width between zero, which is the angular range of the main beam of a radiation pattern between two adjacent zeros to maximum. Create antennas radiated electromagnetic fields. Polarized electromagnetic defined in a certain direction, as the geometric shape that traces the edge of electric field vector at a certain distance from the antenna, to change the time.
Every day use of aerials to transmit and receive signals (data) throughout the world by millions of people is ordinary. General: Everything is connected without cables using in some degree antennas for the exchange of information (data). An aerial is a (metal wire) device designed for the purpose of emitting or receiving electromagnetic waves into free space. A transmitter antenna transforms electrical energy into electromagnetic waves, and a receiver performs the inverse function.
The characteristics of an antenna depends on the relationship between the dimensions and the wavelength of a signal transmitted or received radio frequency. If the masts dimensions are much smaller than the wavelength are called elementary antennas, whether they have dimensions of order of a half wavelength resonating and if its size is much larger than the wavelength are directives.
Within the transmission we can define co-polar diagram that represents the communication from to a desired polarity and polarized radiation pattern with the opposite polarity to that you already have. The most important parameters of the radiation pattern are: pointing direction: The maximum radiation. Directivity and Gain. Main lobe constitutes angular range around the direction of maximum radiation. Side lobes are other relative maxima, lower the principal value.
A typical loop antenna is made of copper, in resonance with a variable capacitor when transmitting and can withstand high voltages. The transmission can take many amps and the voltage across the capacitor several kilovolts. Loops of copper are more effective than lower managers, due to the large flow. Loops are circular and more efficient than squares, an alternative is octagoner that are easier to manufacture.
Comparing an antenna yagi with a satellite, the antenna yagi have a F / B ratio of about 15 dB (depending on model and manufacturer) while for the parabolic relationship F / B is> 35dB (depending on model and manufacturer) . This is observed as "good" antenna on rejection of signals by the rear. The higher the paramentro in parabolic antennas will be better. The 15 dB of antenna yagui it can also be interpreted as the attenuation that would have on the system, if for example a bounced capture of a building, by the rear of the wave. Radiation resistance - when power is supplied to an aerial, radiating part of it and part is converted into heat dissipating. When talking about radiation resistance, it is made taking into account that cannot be measured directly.
If the antenna is replaced by the radiation resistance, this would do their job, ie, would produce the same amount of power that the antenna would radiate. The radiation resistance is equal to the ratio of the power radiated by the aerial divided by the square of the current in its feed point. One could obtain an mast efficiency, given that is the ratio of the radiated power and the dissipated power.
You can also define the beam width between zero, which is the angular range of the main beam of a radiation pattern between two adjacent zeros to maximum. Create antennas radiated electromagnetic fields. Polarized electromagnetic defined in a certain direction, as the geometric shape that traces the edge of electric field vector at a certain distance from the antenna, to change the time.
Every day use of aerials to transmit and receive signals (data) throughout the world by millions of people is ordinary. General: Everything is connected without cables using in some degree antennas for the exchange of information (data). An aerial is a (metal wire) device designed for the purpose of emitting or receiving electromagnetic waves into free space. A transmitter antenna transforms electrical energy into electromagnetic waves, and a receiver performs the inverse function.
The characteristics of an antenna depends on the relationship between the dimensions and the wavelength of a signal transmitted or received radio frequency. If the masts dimensions are much smaller than the wavelength are called elementary antennas, whether they have dimensions of order of a half wavelength resonating and if its size is much larger than the wavelength are directives.
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