A multiplicative system is examined which consists of a 21-element array with a tapered amplitude distribution and a monopole. Radar applications are considered in the following respects:(1) The influence of the distance between the phase-centres on beam-width and side-lobe level.(2) Multiple target response for several relative strengths, phases and angular separations.The results are evaluated using an analyser for complex Fourier series and compared with similar situations in linear arrays. An estimate is given of the unwanted phenomena to be expected. Further experimental research seems to be justified and the difficulties of such experiments are outlined.