  In multi input multi output antenna systems, beamforming is a technique for
guarding against the negative effects of fading. However, this technique
requires the transmitter to have perfect knowledge of the channel which is
often not available a priori. A solution to overcome this problem is to design
the beamforming vector using a limited number of feedback bits sent from the
receiver to the transmitter. In the case of limited feedback, the beamforming
vector is limited to lie in a codebook that is known to both the transmitter
and receiver.When the feedback is strictly limited, important issues are how to
quantize the information needed at the transmitter and how much improvement in
associated performance can be obtained as a function of the amount of feedback
available.In this paper channel quantization schema using simple approach to
codebook design (random vector quantization)is illustrated. Performance results
show that even with a few bits of feedback, performance can be close to that
with perfect channel knowledge at the transmitter.
