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Switched beam systems..................................................................................................... |
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Working...
This is the simplest technique, and comprises only a basic switching function between separate directive antennas or predefined beams of an array. The setting that gives the best performance, usually in terms of received power, is chosen. Because of the higher directivity compared to a conventional antenna, some gain is achieved [1]. Pros & cons.... a.This kind of antenna will be easier to implement in existing cell structures than the more sophisticated adaptive arrays, which also means low cost. b.The signal strength can degrade rapidly during the beam switching. In addition, if the interferer is at the center of the selected beam and the user is away from the center, the interfering signal can be enhanced far more than the desired signal. Dynamically phased arrays ................................................................................. Working... By including a direction of arrival (DOA) algorithm for the signal received from the user, continuous tracking can be achieved and it can be viewed as a generalization of the switched beam concept. Pros & cons... a. In this case, the received power is maximized. b. It does not null the interference.
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