This document describes the scheme and prototype test results of a broadband radioastronomy receiver aimed to obtain polarisation data of Cosmic Microwave Background (CMB) radiation from the sky. Nominal receiver bandwidth is 26 to 36 GHz. The radiometer will work as a polarimeter to obtain the polarisation Stokes parameters (Q, U and I) of the incoming electromagnetic signal to the feed-horns. Prototype tests have demonstrated the receiver concept based on electronic phase switching in two balanced branches. The correlation between signals is performed directly at 31 GHz by a broadband 3 dB/180º hybrid coupler
