This paper characterizes the interferometric phase for a fixedreceiver bistatic SAR system. Also, the expressions for the interferometric phase and image resolution cell are summarized. It will be distinguished between two particular acquisition geometries : back-scattering and forward-scattering. A bistatic interferometric chain has been implemented whose particularities are discussed. The theoretical developments are complemented with the comparison of the Digital Elevation Models (DEM) generated from the bistatic interferometric data acquired with our fixed receiver, named SABRINA (SAR Bistatic Receiver for INterferometric Applications) with a SRTMDEM and a Digital Terrain Model (DTM) from the Institut Cartografic de Catalunya (ICC).