  A major goal of upcoming experiments measuring the Cosmic Microwave
Background Radiation (CMBR) is to reveal the subtle signature of inflation in
the polarization pattern which requires unprecedented sensitivity and control
of systematics. Since the sensitivity of single receivers has reached
fundamental limits future experiments will take advantage of large receiver
arrays in order to significantly increase the sensitivity. Here we introduce
the Q/U Imaging ExperimenT (QUIET) which will use HEMT-based receivers in chip
packages at 90(40) GHz in the Atacama Desert. Data taking is planned for the
beginning of 2008 with prototype arrays of 91(19) receivers, an expansion to
1000 receivers is foreseen. With the two frequencies and a careful choice of
scan regions there is the promise of effectively dealing with foregrounds and
reaching a sensitivity approaching 10$^{-2}$ for the ratio of the tensor to
scalar perturbations.

Astrophysics