B-modes of Cosmic Microwave Background ( CMB ) polarization can be created by a primordial gravitational wave background .
If this background was created by Inflation , then the amplitude of the polarization signal is proportional the energy density of the universe during inflation .
The primordial signal will be contaminated by polarized foregrounds including dust and synchrotron emission within the galaxy .
In light of the WMAP polarization maps , we consider the ability of several hypothetical CMB polarization experiments to separate primordial CMB B-mode signal from galactic foregrounds .
We also study the optimization of a CMB experiment with a fixed number of detectors in the focal plane to determine how the detectors should be distributed in different frequency bands to minimize foreground confusion .
We show that the optimal configuration requires observations in at least 5 channels spread over the frequency range between 30 GHz and 500 GHz with substantial coverage around 150 GHz .
If a low-resolution space experiment using 1000 detectors to reach a noise level of about 1000 nK ^ { 2 } concentrates on roughly 66 % of the sky with the least foreground contamination the minimum detectable level of the tensor-to-scalar ratio would be about 0.002 at the 99 % confidence level for an optical depth of 0.1 .