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What do you mean by directional antenna?
A directional antenna or beam antenna is an antenna which radiates or receives greater power in specific directions allowing increased performance and reduced interference from unwanted sources. Satellite television receivers usually use parabolic antennas.
What is the use of directional antenna?
Directional antennas pull in signals better from one direction. In this direction, they can detect a weaker or more distant signal than an equivalent omnidirectional antenna. The trade-off is that they do this by decreasing their ability to pull in signals from other directions.
What are the characteristics of directional antenna?
Directional antennas usually exhibit unidirectional properties. In other words, their maximum gain (increase in efficiency) occurs in a single direction. So-called bidirectional antennas have two high-gain directions, usually oriented opposite to each other in space.
What is MIMO in 5G?
Multiple-input/multiple-out (MIMO) technology is an established wireless communications technique for sending and receiving multiple data signals simultaneously over the same radio channel. Massive MIMO uses many more transmit and receive antennas to increase transmission gain and spectral efficiency.
How does MIMO 5G work?
MIMO systems require a combination of antenna expansion and complex algorithms. MIMO algorithms come into play to control how data maps into antennas and where to focus energy in space. Both network and mobile devices need to have tight coordination among each other to make MIMO work.
How are phased array antennas used for beamforming?
A phased array antenna enables beamforming by adjusting the phase difference between the driving signal sent to each emitter in the array. This allows the radiation pattern to be controlled and directed to a target without requiring any physical movement of the antenna.
When to use analog vs.digital beamforming?
Concepts like beamforming and analog vs. digital become part of the discussion when the topic turns to “What’s next?” In high frequency mmWave transmission, large path loss during signal propagation limits the transmission range; to overcome this obstacle, directional antennas with beamforming abilities are used in transmission and reception.
What are the different types of beamforming techniques?
These different types of beamforming techniques find applications in scanning sonar, radar (see the large Duga-3 phased array above), WiFi, and soon MU-MIMO in 5G. The poor-man’s way of doing beamforming is to simply switch the transmitted signal between different directional antennas with an RF switch.
How are antenna arrays used in beam scanning?
In beam scanning, a single main beam of an array is steered and the direction can be varied either continuously or in small discrete steps. Antenna arrays using adaptive beamforming techniques can reject interfering signals having a direction of arrival different from that of a desired signal.