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Antenna array may refer to:

• an interferometric array of radio telescopes used in radio astronomy.
• a phased array, also known as a smart antenna, an electronically steerable directional antenna typically used in RADAR and in wireless communication systems, in view to achieve beamforming, multiple-input and multiple-output (MIMO) communication or space-time coding.
• See below:

An antenna array is a group of isotropic radiators such that the currents running through them are of different amplitudes and phases. These are radiators of EM frequency and energy. Antenna arrays are the solution to the problem defined as the limitations of operating a single antenna. An example of the problem is that although a dipole antenna allows for better control of direction than an isotropic(omni-directional) antenna, as the length of the dipole increases, the control of direction decreases. Hence control by changing the length of a single antenna is very limited. Greater flexibility and control can be obtained for directing the beam with an arrangement of multiple radiators.

There are a few different general types of antenna arrays. When the array is arranged in a straight line this is called a linear array. Antennas arranged in parallel lines on one plane has a plane array in two dimensions. Many planes in a group of arrays or antennas results in a three dimensional array. An antenna array may consist of a group of isotropic (omni-directional) radiators. Or, the array may have a group of radiators that are identical. In a group of identical radiators all the antennas must be share the same orientation in space. The same orientation results in the desired effect of reinforcement or cancellation of the electric field intensity. The same orientation ensures polarization in the same direction in space.

References

1. ^ Swarte, V.V. (1993, Reprint-2006). Electromagnetic fields and waves. New Dehli: New Age International Ltd. pp. 396, 397. ISBN 8122404685. {{cite book}}: Check date values in: |date= (help)

• Disambiguation pages