[理学]inmarsat bgan系统.ppt

* High level definition of BGAN Platform BGAN is an Inmarsat platform for delivering ‘always on’ Internet Protocol Services, telephony and ISDN Using the new I4 Satellites and a new generation of lighter, smaller terminals, the BGAN system delivers higher data rates at lower costs than any other previous Inmarsat system The BGAN Core Network component is essentially a COT 3G network that would be found typically on terrestrial mobile 3G networks. B-nodes removed User equipment communicates across L band link anywhere with line of sight to an I4 satellite Inmarsat is developing evolutions to BGAN to offer service in other market segments: land mobile (including vehicular), aviation and maritime. Enterprise’ (Land portable) segment in IOR in December 2005 and in AOR-W in May 2006. Infrastructure tried and tested These evolutions run over the same ground infrastructure as ‘Enterprise’, share the same RF carriers, are broadly the same but are optimised/tailored for the specific environment. * Describe BGAN System components integral to SwiftBroadband * Global is about 40% of Earths surface * * * Burum * In terrestrial UMTS a RAN consists of a number of RNS (Radio Network subsystem) that in turn consist of a RNC (Radio Network Controller) and multiple Node-Bs (Base Transceiver Station). The RNC terminates the Iu interface from the core network and provides radio bearers towards the mobile users for signalling and traffic transport using the air interface. The functions of the RNC are: ? Radio Resource Control ? Admission Control ? Channel Allocation ? Power Control Settings ? Handover Control ? Ciphering ? Segmentation / Reassembly ? Broadcast Signalling * The diagram outlines the basic architecture of the BGAN ground network. Notice that there is redundancy built into this as there are two SASs at each site and that these are interconnected. Both lie within the coverage of F1 and F2. Both sites have interconnects to the Inmarsat Head Office in Londo