SVD is a method to cancel the interference in MIMO system,we often do the SVD of channel as below
\begin{align} \mathbf{H} &= \mathbf{U} \ \Sigma \ \mathbf{V}^{T} \\ % \end{align}
So $ \mathbf{U}$ means the beamforming direction of receiver? and $\mathbf{V}$ means the beamforming direction of transmitter? and the singular value in the diagonal of $\Sigma$ means the gain of channel ?Why can we use this to decrease or cancel the noise ?