  In this paper, we propose a Singular-Value-Decomposition-based
variable-resolution Analog to Digital Converter (ADC) bit allocation design for
a single-user Millimeter wave massive Multiple-Input Multiple-Output receiver.
We derive the optimality condition for bit allocation under a power constraint.
This condition ensures optimal receiver performance in the Mean Squared Error
(MSE) sense. We derive the MSE expression and show that it approaches the
Cramer-Rao Lower Bound (CRLB). The CRLB is seen to be a function of the analog
combiner, the digital combiner, and the bit allocation matrix. We attempt to
minimize the CRLB with respect to the bit allocation matrix by making suitable
assumptions regarding the structure of the combiners. In doing so, the bit
allocation design reduces to a set of simple inequalities consisting of ADC
bits, channel singular values and covariance of the quantization noise along
each RF path. This results in a simple and computationally efficient bit
allocation algorithm. Using simulations, we show that the MSE performance of
our proposed bit allocation is very close to that of the Full Search (FS) bit
allocation. We also show that the computational complexity of our proposed
method has an order of magnitude improvement compared to FS and Genetic
Algorithm based bit allocation of $\cite{Zakir1}$
