Next generation mobile satellite communications systems involve various types of traffic, including telephone, satellite SCADA and mobile hot spot traffic. The traffic will be broadband up to 1Gbps. To achieve such systems in the S band at affordable cost, innovations in satellite on-board technology will be required along with the adaptive modulation application. This paper introduces the concept of next generation mobile satellite communication and outline the requirements for the on-board equipment. It also presents a multi-beam feeder with a beam-group concept and an adaptive filter as enabling technology for such systems. The multi-beam feeder technique can provide sufficient satellite antenna gain all over the coverage area while enabling power to be focused on the needed beams. The communication capacity can be significantly enhanced with a meticulous resources assignment, which entails a complicated spectrum layout on the feeder link. The on-board adaptive filter allows the feeder link to be packed while maintaining the enhanced capacity.