Multipath reflections are usually a source of lack of accuracy in antenna measurements. The Matrix Pencil method has demonstrated to be an accurate algorithm to identify the direct wave and the reflected one in semi-anechoic chambers measurements. In this paper, this method has been used to retrieve antenna radiation pattern measured in non anechoic environment. Very good accuracy between reference data and retrieved data has been found for directive antennas and reasonable good accuracy has been found for a wideband omnidirectional monopole.