Abstract: The present invention relates to a device for measuring characteristics of an electromagnetic field emitted by a source being tested, comprising a radiating element (8), a support (6) for said radiating element and a mount (5) on which said support is fastened. It is characterized in that it comprises a screen (7) carried by said support (6) and interposed between said radiating element (8) and said mount (5), and in that said screen (7) is adapted to reflect the beams (R1, R2) impinging upon it so as to re-emit and scatter them into space, along determined directions (R?1, R?2). In the measuring device wherein said radiating element (8) is associated with the sighting axis (?), so as to point the measuring device (4) along determined measuring directions, said screen (7) can be shaped such that said determined directions (R?1, R?2) include large amplitude angles with said sighting axis (?). The measurement site can comprise an anechoid chamber (9) enclosing said source and having walls (90).