Dipole antenna
Other antenna types include the “dipole”, where a section of wire, one-half the wavelength, is positioned either horizontally or vertically in the air to transmit signals. Dipoles emit their signals in more of a two dimensional semi-circular or “doughnut” pattern, the key being both the transmitter and receiver’s antennas must be aligned the same (horizontally or vertically). Dipoles do not require a ground-plane are considered “bi-directional,” in that their signals travel in two opposite directions, depending on how the antenna is oriented .
Yagi antenna
The more focused (uni-directional) type of antenna is called a “Yagi.” A Yagi antenna is basically a standard one-half wavelength antenna, but with additional “elements” placed in front of it to focus the energy for transmission in one direction. The “reflector” and “director” elements are just similar-sized resonators spaced appropriately to increase the strength and narrow the direction of the signal prior to transmission. Again, the key to successfully using Yagi antennas is the correct orientation and alignment of the transmitting/receiving antennas.
Sectoral antenna
The requirement to serve a number of small areas from a single base station has resulted in the development of the multiple beam technique, for which the sectoral antenna is ideal .
Parabolic Reflector antenna
This antenna consists of a parabolic metal surface (dish) with a feed antenna in front. The feed antenna consists of a directive antenna such as a dipole and reflector, log-periodic dipole array or horn antenna. This antenna is capable of producing extremely high gains, usually in the 20 - 30 dBi range
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Microwave antenna
Other antenna types include the “dipole”, where a section of wire, one-half the wavelength, is positioned either horizontally or vertically in the air to transmit signals. Dipoles emit their signals in more of a two dimensional semi-circular or “doughnut” pattern, the key being both the transmitter and receiver’s antennas must be aligned the same (horizontally or vertically). Dipoles do not require a ground-plane are considered “bi-directional,” in that their signals travel in two opposite directions, depending on how the antenna is oriented .
Yagi antenna
The more focused (uni-directional) type of antenna is called a “Yagi.” A Yagi antenna is basically a standard one-half wavelength antenna, but with additional “elements” placed in front of it to focus the energy for transmission in one direction. The “reflector” and “director” elements are just similar-sized resonators spaced appropriately to increase the strength and narrow the direction of the signal prior to transmission. Again, the key to successfully using Yagi antennas is the correct orientation and alignment of the transmitting/receiving antennas.
Sectoral antenna
The requirement to serve a number of small areas from a single base station has resulted in the development of the multiple beam technique, for which the sectoral antenna is ideal .
Parabolic Reflector antenna
This antenna consists of a parabolic metal surface (dish) with a feed antenna in front. The feed antenna consists of a directive antenna such as a dipole and reflector, log-periodic dipole array or horn antenna. This antenna is capable of producing extremely high gains, usually in the 20 - 30 dBi range
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