[SatNews] NSSLGlobal Ltd. and Telemar Scandinavia become the first satellite providers, in conjunction with...
...their core technology partner STM, to announce the introduction of ACM (Adaptive Coding and Modulation) combined with the new DVB-RCS2 standard across all their VSAT network Hubs and customers, with the switch-over taking place by the end of March. The industry leading DVB-RCS2 standard recently underwent a technology leap, bringing the potential of satellite communications to a whole new level. The ACM in DVB-S2 carriers alongside the new ACM capabilities in the DVB-RCS2 standard ("RCS2") for TDMA carriers not only improves 2-way satellite link efficiencies it also rockets throughput potential by up to 250 percent as well as providing up to 2dB more gain allowing extended coverage and link availability in what was previously edge of beam.
ACM, one of the latest developments in DVB technology, counters the problem of Rain Fade; the degradation of signal integrity in poor weather conditions. ACM enables dedicated management of each individual VSAT unit within a spot-beam. It allows the signal sent to each unit to be optimised specifically for the location and interference levels of that individual unit. Previously the signal sent through from the network hub was either fixed, or compensating for the worst conditions any of the individual units suffered. However, with dedicated signal management provided by ACM the network Hub can regulate each VSAT individually, ensuring that every unit receives the optimum signal quality for its specific location and conditions.
The implementation of ACM will have a resounding effect on the performance of the VSATs within the network. The modification will yield improvements of 40 to 100 percent bandwidth efficiency to units affected by Rain Fade, as well as providing an increased coverage area and graceful service degradation during poor conditions. In addition, the major advance from DVB-RCS to DVB-RCS2 offers 8PSK and 16QAM modulation options as well as the usual QPSK, providing additional gain of up to 2dB. Particularly important is that ACM is also implemented on the TDMA carriers allowing for dramatic improvements in average network capacity and link availability over TDMA carriers in high-frequency satellite networks without increasing antenna sizes.

