13-04-2013, 03:59 PM
SMART ANTENNAS
SMART ANTENNAS.pptx (Size: 368.02 KB / Downloads: 35)
What is SMART ANTENNA ?
A smart antenna consists of an antenna array, that changes the array pattern in response to Signal environment to improve the performance of a communication system
SWITCHED BEAM ANTENNAS
These antenna systems detect signal strength, choose from one of several predetermined, fixed beams, and switch from one beam to another as the mobile moves throughout the sector.
ADAPTIVE ARRAY ANTENNAS
Adaptive antenna technology provides optimal gain while simultaneously identifying, tracking, and minimizing interfering signals.
SDMA(SPACE DIVISION MULTIPLE ACCESS
More than one user can be allocated to the same physical communications channel simultaneously in the same cell separated by angle only.
This is the next step in an evolutionary path toward increasing the capacity of cellular systems.
CONCLUSION
A smart antenna is a digital wireless communications antenna system that takes advantage of diversity effect at the source (transmitter), the destination (receiver), or both.
SAS can generate a set of “flexible” beams. In what follows, the pattern, beamwidth, and gain of each beam can be adjusted even adapted individually to optimize the capacity of a CDMA network.
Specifically, unlike the conventional scheme, no tower climbing and no physical changing of antenna orientation are needed. All the required sector orientation and beamwidths are software-controllable, remotely configurable.