In this paper, an original focal array for multibeam antenna is presented. It is based on Multiple Feed per Beam geometry. Each beam is produced by a cluster of feed horns illuminating a parabolic reflector. Three adjacent clusters of the focal array overlap for enhancing the illumination performance within the size-constrained array lattice. The Beam-Forming Network is the key component and drives the overall performance of the radiating structure. It is composed of tri-dimensional interleaved couplers made of circular waveguides and interconnected by thin radial rectangular waveguides. The design, manufacturing and measurement of a Ka-band Multiple Feed per Beam focal array are reported. It is composed of 31 feed horns displayed in 7 clusters, for a global size of about 6λd where λd denotes the free-space wavelength at the lowest operating frequency. The realized gain is higher by 1dB than the gain provided by the Single Feed per Beam focal array having analogous size.