Narrow spotbeams satellite systems are nowadays being deployed by most of the satellite operators: IPstar by Thaicom in Ku band, Viasat-1, Hylas-1 by Avanti, Ka-Sat by Eutelsat, YahSat-1A and-1B, and hosted payloads are also embarked by satellite operators such as SES or Arabsat. There is a clear trend towards narrower spot beams and the generalisation to all frequency bands, from C band to Ka band. Intelsat recently announced also its EPICTM initiative. To achieve a large number of beams, a classical approach is to have each of the beams created by a single feed: as many feeds as beams need to be created; this is a Single Feed per Beam (SFPB) approach. To generate the full coverage, three to four antenna apertures are needed, each reflector offering transmit (Tx) and receive (Rx)simultaneous operation. Thermal distortion of these multireflector systems creates a differential depointing of the reflectors, which induces degradation of the radio-frequency coverage. With such an SFPB solution the ever-increasing number of beams leads to a corresponding increase in the number of feeds, which has a significant impact on antenna complexity, mass and accommodation requirements. Altogether the accommodation constraints imposed by the satellite platform and/or the launcher may be violated. To alleviate accommodation limits, multiplefeed- per-beam (MFPB) reflector antennas, generating a high number of beams with a single antenna aperture, offer clear advantages. So far only Tx or Rx operation has been possible from a single aperture due to the antenna complexity. With the development of narrow beam satellite payloads in all frequency bands, it would be highly beneficial if satellite system integrators could propose more compact solutions to satellite operators, leading for instance to hosted payloads in either C-, Ku or Ka bands. The purpose of this activity is thus to demonstrate the benefits of such a compact solution for a satellite operator and to define the efforts required to develop an antenna supporting this concept. The activity shall be performed considering the C, Ku and Kabands (the budget is for the three frequency bands), leading to potentially different solutions for the different frequency bands. Some possible configurations that could be studied and traded-off are anticipated. Among others, one may refer to (a) SFPB oversizedshaped reflector antennas (b) MFPB reflector antennas operating in TX and RX, employing diplexers at feed level; (c) Discrete LensAntennas in which the lens aperture is shared by the TX and the RX elements and implementing two physically separated RX and TX feed clusters. The following approach shall be implemented (1) Definition of a reference mission and accommodation requirements (2) Definition of metrics for assessments of benefits against state of the art solutions (3) Survey of potential antenna architectures and selection of the preferred solutions (4) Assessment at system level (payload and satellite) and presentation to selected satellite operators to gather feedback (5) Detailed analysis of selected solutions (6) Definition of a development roadmap(7) Synthesis.