Calculations of attainable values for space resolution and radiometric sensibility of a spaceborne two-dimensional synthetic aperture microwave polarimetric interferometer are carried out. It is shown that for the most preferable Y-shaped interferometer configuration, it is possible to achieve (within the transparency windows of waveband 3--22.5 mm) a space resolution of 0.5--1 km and a radiometric resolution close to 1 K at the receiver bandwidth of 100 MHz. For cross- and T-shaped resolutions, values close to the above can be reached.