Digital Beam Forming Using Orthogonal Frequency Division Multiplexing in Wireless communication Systems:A Review

Abstract

Transmit beam forming with receive combining may be a simple technique for exploiting the
numerous diversity provided by multiple-input multiple-output (MIMO) systems, and
therefore the use of orthogonal frequency division multiplexing (OFDM) allows low quality
implementation of this theme over frequency selective MIMO channels. This paper proposes
a beam forming technique that reduces feedback necessities for optimum beam forming.
Within the projected design, the receiver send back quantized versions of choose beam
forming vectors and the transmitter reconstructs the missing beam forming vectors through
interpolation. Since a beam forming vector is part invariant and has unit norm, a
replacement spherical linear interpolator is proposed that exploits extra parameters for part
rotation. These parameters square measure determined at the receiver within the sense of
maximizing the minimum channel gain or capability, and sent back to the transmitter
alongside the quantized beam forming vectors. Simulation results show that the projected
beam forming method needs abundant less feedback data than optimum beam forming with
solely slight diversity loss.