Thispaperdescribes current developments inAlcatel SpaceIndustries carried outonanewconcept ofbeamforming network, realized bymolding assembly and using new3DRFpackaging technologies and interconnections. Theaimistobeableto address alarge panel ofapplications without anyconcept ortechnology majorchanges. I.INTRODUCTION Active antennas forsatellite systems dedicated tomultimedia demandincreasing complexities, especially intermofbeamnumber (m)managed byeachsingle radiating element (nradiating patterns). SoBFNfunctionality iswidened, asit mustinsure powerdivision fromm x1tom xn andalso recombination fromm xnto1xn: - routing ismoreandmoredenseand difficult, particularly toobtain thesame electrical paths forallthesignals, solosses inevitably increase, - theseveral beamsmustbemanaged in amplitude andphase, sochip(attenuator and phase shifter) integration becomes necessary. Nowadays,organicmultilayer PCB technologies arethebest suited torealize beam forming networks. However, these technologies do not fulfill anymorethe following requirements: - whenworking frequency exceeds 20 GHz,RFmultilayer interconnections state of theart, (ofmetallized viaholes, forexample), reaches its limit, - forchip integration inside BENitself, as multilayer PCB realization process (lamination, pressure, thermofusion) is usually incompatible with component insertion inmultilayer. Thisdrawback implies that chips mustbeexternalized. Moreover, theseBFNs arebuilton a honrzontal layer stacking model, whichcreates important constraints onperformances (generally narrowbandwidth) andon interconnection dimensions withradiating elements, placed perpendicularly toBFN.