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Satellite Communications Systems and Emergency Communications Dr. Joseph S. Bravman Omnisat, LLC December 12, 2005 Why Satellites • Advantages – – – – Highly portable & ubiquitous connectivity Independent of damaged or unreliable infrastructure Assured access Work well to interconnect hybrid network links • Issues – – – – Beyond Line of Sight limitations Can be expensive or unfamiliar Often not what is in use at local level GEO Delays cause unexpected IT problems Commercial Satellite Markets • Communications – Backhaul Capacity – VSATs & Private Networks – Broadcast (DTH & SDARS) – Internet & IP based – Satellite Telephony – Misc. • Navigation • Remote Sensing Shares Solutions with Urban Warfare • Similarities – Need for collaboration – Similar operating environment – Complex interoperability and multilevel security • Differences – Dual use and commercial technologies are more easily embraced – No export issues with coalitions – AJ/LPI/LPD not a major factor – Less issue with sharing with civilian population Elements of Emergency Communications • Phases of a disaster or event – – – – – Monitoring & preparation Warning Crisis Mitigation & management Restitution • System elements expand and contract through these phases • Communication system functions – – – – – – Sensor communications Broadcast communications Command & control Collaboration Tactical communications Communications restitution The Problem & the Solution • Fragmented nature of responders - Stovepipes & Interoperability issues • “Bring your own” – small, low cost and flexible equipment • Leverage off high impact commercial technology • Mix of push and collaborative pull on data sets • Caching with automated updating • Multi-node • Optimal use of spectrum for bandwidth and coverage • Hybrid networks solve non-LOS and create local resiliency • Satellites independent of infrastructure • Secure interaction with flexible authorization required • User attributes are used to tailor data transfer • Must be scalable at all levels Platform Features • Multilevel security - encrypted data transfer with distributed administration • Assures access due to multi-tier priority scheme and automatic queue management • Packetization and data scheduling provides flexibility and efficiency in intermixing and transferring all types of files (data, software, commands, media) • Version control allows simultaneous operation of multiple versions • Conditional access defines >10 million users or user groups • Files are assigned address to create bundles of information ( >10 million addresses are initially provided) • Conditional access insures that the right information gets to the correct user using address fields & can be changed at any time • Geocoding can be added to provide convenient additional filter • System time is distributed and controls timed features Hybrid Network Various Satellite Systems . Various Satcom Uplinks Multiple terminals link to mesh for redundancy Data Data is cached & locally archived Local Cache . Internet Mesh Mobile Terminal Additional Fixed Sites connected by conventional means or Satcom terminals Mesh PDA with Wireless Mobile & Portable assets Laptop with Wireless Packet Radio Mesh Network Mesh ` Fixed & transportable assets Mesh Uses of terminals • Packet Radio nodes create resilient mesh • Ad hoc users gain local and long range connectivity beyond LOS • Command and control features may be remoted to field • Push/broadcast fills local cache with information that is likely to be required • Collaborative software allows multimedia interactivity • Terminal characteristics are transmitted to control resolution, etc. to minimize overwhelming links and processors Communications Elements 50 Mb/s 5 Mb/s 500 Kb/s 50 Kb/s 5Kb/s P A C K E T R A D I O Local Ku/Ka-Band Satellite L/S-Band Satellite UHF/VHF Satellites Regional Continental Satellite Solution Advantages • Satellites provide instantaneous dissemination of information and a common operating picture – Gets it to the user faster and at low cost. • Satellite systems not susceptible to terrestrial boundaries and costs. Easily becomes part of hybrid solution. • System solution benefits from off-the shelf components leading to overall affordability and quick implementation – But must be efficiently integrated with open standards • System must be valuable beyond crisis usage – critical to business case • Demonstrations and rapid prototyping propels fieldable solutions