Resource Management in Satellite Networks part 35. This book provides significant knowledge on innovative radio resource management schemes for satellite communication systems that exploit lower layer adaptivity and the knowledge of layer 3 IP QoS support and transport layer behavior. The book integrates competencies considering all the parts of system design: propagation aspects, radio resource management, access protocols, network protocols, transport layer protocols, and more, to cover both broadband and mobile satellite systems | Chapter 10 CROSS-LAYER METHODS AND STANDARDIZATION 329 techniques especially in the return link for terminals with small antennas. The adoption of spectrum spreading is a possible solution to reduce the EIRP while preserving the required SNR at the expenses of reduced spectral efficiency. In the forward link the introduction of spreading requires the design of a new DVB-S2 receiver. In the return link each terminal could in principle implement direct spreading within the assigned time and frequency slot MF-TDMA approach . Fading countermeasures the more challenging propagation conditions of the non-LoS scenario can be mitigated by adopting advanced techniques such as diversity and higher layer FEC schemes. Moreover new synchronization acquisition and maintenance procedures need to be employed to cope better with frequent fades. Resource management techniques efficient RRM schemes need to be adopted to account for mobility such as impact of spreading on the MF-TDMA allocation process DVB-RCS support of handover requests with suitable protocols interworking with terrestrial networks in shadowed areas . tunnels cities etc. where gap fillers can be used adaptive schedulin techniques for the forward link that are aware of the physical layer behavior. All these innovative aspects require a cross-layer system design aiming at optimizing the choices made at different layers. The DVB-TM is now working to specify the modifications that are needed for the mobile extension of the DVB-S2 standard 23 . The SatNEx II project 24 is actively involved in this standardization process. DVB-H The broadcast of digital television signals was originally targeted to fixed reception although mobile reception is also feasible with current digital television standards DVB-T DVB-S2 . The Commercial Module of DVB decided to launch commercial requirements for the production of ad hoc specifications able to provide broadcasting to one specific niche of the mobile receivers handheld terminals.
