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SatMagazine

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Title:
SatMagazine
Alternate title:
Sat magazine worldwide satellite magazine
Place of Publication:
Sonoma, CA
Publisher:
SatNews Publishers
Publication Date:
Frequency:
Monthly
regular
Language:
English
Physical Description:
volumes : illustrations ;

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Subjects / Keywords:
Artificial satellites in telecommunication -- Periodicals ( lcsh )
Artificial satellites in telecommunication ( fast )
Genre:
serial ( sobekcm )
periodical ( marc )

Notes

Dates or Sequential Designation:
Vol. 1, no. 1 (April 2003)-
General Note:
"Your satellite connection to the world."

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University of Florida
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University of Florida
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Copyright, SatMagazine. Permission granted to University of Florida to digitize and display this item for non-profit research and educational purposes. Any reuse of this item in excess of fair use or other copyright exemptions requires permission of the copyright holder.
Resource Identifier:
173221287 ( OCLC )
ocn173221287

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University of Florida
Digital Aerospace Collection

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SatMagazine February 20101 The U.S. Satellite Market S at M a g azi n e W o r l d wid e Sa t ellit e Ma g azi n e February 2010

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SatMagazine February 20102

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SatMagazineVol. 3, No. 1February 2010Silvano Payne, Publisher + Writer Hartley G. Lesser, Editorial Director Pattie Lesser, Editor P.J. Waldt, Associate Editor Chris Forrester, Associate Editor Michael Fleck, Contributing Editor Simon Payne, Development Manager Authors Chris Forrester Thierry Guillemin Hartley Lesser Pattie Lesser John Monahan Tony Radford Thierry GuilleminPublished monthly by Satnews Publishers 800 Siesta Way Sonoma, CA 95476 USA Phone: (707) 939-9306 Fax: (707) 838-9235 2010 Satnews Publishers We reserve the right to edit all submitted materials to meet our content guidelines as well as for grammar and spelling consistency. Articles may be moved to an alternative issue to accommodate publication space requirements or removed due to space restrictions. Submission of content does not constitute acceptance of said material by SatNews Publishers. Edited materials may, or may not, be returned to author and/or company for review prior to publication. The views expressed in our various publications do not necessarily reflect the views or opinions of SatNews Publishers. All included imagery is courtesy of, and copyright to, the respective companies. BEAM Intro The editors >>>>>>>>>>>>>>>>>>>>>>> 4BEAM Doing More With Less By John Monahan, RT Logic >>>>>>>>>>>>> 5 CONTENTS Cover images: WISE launch and spacecraft, courtesy NASA + United Launch Alliance >4 >5 >8BEAM A Good Deal, Or No Deal? By Northern Sky Research (NSR) >>>>>>>>> 8INSIGHT Being Global Is Not The Key By Chris Forrester >>>>>>>>>>>>>>>>>> 14INSIGHT New Or Used? By Tony Radford, Paradise Datacom >>>>>>> 25EVENT CABSAT MENA 2010 By CABSAT >>>>>>>>>>>>>>>>>>>>>> 38EVENT AOG 2010 By PacTel International >>>>>>>>>>>>>> 41FOCUS The Future Of Air Traffic Comms By Dr. Marcus Werner, TriaGnoSys >>>>>>> 31FOCUS A WISE Project By JPL / NASA >>>>>>>>>>>>>>>>>>>> 53FOCUS Combatting Satellite Interference By Thierry Guillemin, Intelsat >>>>>>>>>>> 45TECH CHANNEL What Is Network Latency? By O3b Networks >>>>>>>>>>>>>>>>>> 69 >14 >25 >55

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SatMagazine February 20104 BEAMThis past year has been rather interesting for the U.S. satellite industry. While some companies have faired extremely well, others have felt enormous pressures descend upon them as global competition works its will upon the various SATCOM segments most specifically the satellite manufacturing and launch markets to say nothing of the decrease in capital spending across the globe. We are not in the business of prognostication. We present fact and opinion however, from all of our various contacts and analysis of accounts from within the industry, 2010 seems ready to offer far more in the way of positive, rather than a negative, business outlook for the U.S. satellite industry. Some of these observations are based upon the following facts...New technologies and ideas abound New companies are arriving on scene with strong financial bases and talent New thoughts and tactics are being employed to reduce costs Companies are testing and entering new market segments, resulting in growth Cooperation between competitors enables all to profit from shared resources Increasing global competition for the U.S. satellite market is forcing a re-evaluation of business strategies to ensure prime supplier positioning Perhaps so, with cooperation comes... innovation through motivation! The Editors

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SatMagazine February 20105 Due to budgetary pressures by the US Government, there will be renewed interest in providing new, modernized capabilities through technical refreshment efforts. Upgrading a legacy ground system through a technical refresh offers many advantages over a new-start acquisition. Capabilities can be provided in a timely and cost effective manner. Risk can be reduced by taking a phased approach to adding new, modernized features. oing More With Less BEAMD

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SatMagazine February 20106 A more responsive system hardening capability is possible through on-going information assurance upgrades to counter evolving cyber threats. perform the same missions that, in not only solve current problems, but but also simplifies logistics/sustainment maintenance of the fielded capability. By taking a technical refresh approach, participate in the development activities. Without the programmatic burdens of a more agile technology companies to play a bigger role in solving legacy ground system problems. These companies tend to be more responsive to customer needs BEAMeffective solutions compared to the more established, bigger primes. About the commentatorJohn Monahan is President of RT Logic, Systems. RT Logic has been supporting provided the space sustainment capabilities including: modems, receivers, front-end devices, red/black separation devices, and more. RTL has an unmatched reputation for solving the toughest obsolescence issues and developing and integrating capabilities into

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SatMagazine February 20108 BEAM Protostar I and Ariane 5 launch vehicle images courtesy of ArianespaceProtoStars Satellites A Good Deal, Or No Deal? The October 29th sale at auction of the ProtoStar-1 satellite for $210 million to Intelsat raised a few eyebrows in the industry as some immediately questioned whether Intelsat had overpaid.Northern Sky Research

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SatMagazine February 20109 BEAM jumped to this contention or, at a minimum, argue that Intelsat has made insufficient information publicly available to independently judge if they paid a fair price for ProtoStar-1. There are of course many issues that to estimate the value of a satellite asset, and the simple fact is that not all satellite of the key issues that must be assessed by any operator considering buying an Do You Have A Slot?While a seemingly obvious first question, majority of potential bidders for an asset like ProtoStar-1. Especially given the history surrounding this satellite, any serious bidder has to have solid rights frequency plan. This includes both uplink the satellites transponder capacity that transponders, that are broadcasting both in the FSS and BSS segments. the ProtoStar-1 satellite does not have this satellite if it already had rights to a slot and frequencies that covered, or nearly so, the entire broadcast range of the satellite.Do The Frequency Coordination + Footprint Match?Assuming an operator interested in an in-space asset has an adequate slot, slot and frequencies are coordinated allocated frequencies and, specifically, if the coordination applies to the actual footprint of the satellite. For for footprints covering Europe, but if it is not coordinated for a footprint over the Middle East and Africa, even if an operator has a slot, they could have problems selling capacity. So again in the ProtoStar-1 case, the satellite has more inherent value to slot, but has a good coordination (or precedence in its filings for eventual coordination negotiations) for the specific have at the location.Is There Demand For The Capacity At The Location?The third issue again seems simplistic, but is in fact critical. A satellite operator may

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SatMagazine February 201010 have a good slot that is coordinated, but demand for the capacity at the slot? value of the satellite and coordinated capacity that is of no use if there is no one to sell it to. Conversely, if a satellite operator does see demand, then the be reasonable (but not certain) to assume that the main target market is in fact Africa and the Middle East. Assuming this is correct, ProtoStar-1 in net present value terms. This is because they can almost immediately begin serving demand in Africa and the (again assuming Africa and the Middle East are in fact the target market) because there is currently substantial unmet from Demand, 6th Edition fill rates could drop substantially in than demand in Africa and the Middle East. By beating its competitors to of this demand at the prevailing higher capacity pricing before others reach the on capacity pricing as supply increases.What About ProtoStar-2?While certainly not the only issues that bidding for ProtoStar-1, the above three BEAM Protostar 2 satellite, image courtesy of Boeing

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SatMagazine February 201011 slots) and paid the price it did (and can start tapping demand immediately). The above three points also prove interesting if they are applied to the upcoming ProtoStar-2 auction. Again, the issue of having an available slot that is coordinated bidders. ProtoStar-2 is also relatively of the satellite for DTH services. This complicates the financial evaluation of ProtoStar-2 because any slot too far 107.7 degrees East essentially zeros out the net present value of the S-band payload since there is very little (if any) demand be highly concerned about even a small The above seems to give an advantage to SES World Skies in the ProtoStar-2 the closest slot ( 108.0 degrees East NSS-11 East slot does not have substantial, if any, one hand, this implies that an eventual purchase of ProtoStar-2 by SES could be BEAM

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SatMagazine February 201012 location? The fact that the company contract yet for this location (their interference, but potential future To further support this argument, and AsiaSat has left no doubts about an eventual purchase of ProtoStar-2, and bid for the satellite. And again, moving the S-band payload. All of the above leads NSR to speculate that ProtoStar-2 might in fact fetch a other issues not addressed here are the purchase decision. from the NSR report entitled...Global Assessment of Satellite Supply and Demand, 6th EditionAbout NSRNorthern Sky Research (NSR) is an international market research telecommunications technology and applications. NSR primary areas of media applications. geographic regions and a number of telecommunications sectors, NSR is a leading provider of in-depth market insight and analyses. Since each NSR product is based on future perspectives, step ahead of the competition and plan for future opportunities in all markets. reputation as a premier market research leading publications. BEAM

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SatMagazine February 201013 BEAM

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SatMagazine February 201014 >1 Eutelsat fleet >2 W2A >3 KA-SAT >4 W3B >5 EUROBIRD 9A >1 >2 >3 >4 >5

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SatMagazine February 201015 INSIGHT eing Global Is Not The KeyBMichel de Rosen, is settling in well in his new role. Former CEO Giuliano Berretta is now the Parisnon-executive chairman following his retirement to day responsibilities. Mr. de Rosen, who enjoyed a long career in the pharmaceutical sector, stressed that in some way he is at a disadvantage chief execs.FORRESTER

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SatMagazine February 201016 company is in bad shape. Well, that Giuliano has left us a strong company. built for the short and medium term and He outlined a series of possibilities, topic he returned to more than once, of priorities is Solaris Mobile, Eutelsat SES, to see S-band W2A Solaris has banked an insurance cheque for some 133 million euros as antenna failure to meet its specifications. Solaris Mobile is, says Mr. de Rosen, understood they have been able to arounds, and thus have time to fully consider options. INSIGHT Mr. de Rosen is on record as saying the Eutelsat must not be sucked into a comfortable state of selfsatisfaction. Business journals are littered with stories of companies that, in the belief they were the greatest, were toppled off their perch by someone else trying harder, said de Rosen. The bankers often tell us you must be global. I ask them why? Michel de Rosen, CEO, Eutelsat

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SatMagazine February 201017 time to fully understand the situation community for the claim. The agreement the system, and to regulators at national and European level to see the licences fully developed. have yet to be active are doing and going to and convincingly these Mr. de Rosen said that Solaris market, especially in regard to potential development of mobile video services in Europe anticipated, and the fact not moved faster than the reality. The transmission system is beaming S-band/DVB-SH video and audio signals to some test vehicles. Customers or more accurately, potential customers have already seen INSIGHT

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SatMagazine February 201018 for the upcoming 3G Global Forum, and sound like. And it is impressive. A test drive offered radio services, and most importantly drop-out or other troubling artefacts. solution beams a mini-WiFi signal into the car, enabling up to three different images iPhone potentially dozens of different users (on and other vehicle-based telematics is a key advantage.Currently, the scheme assumes the repeaters filling in the local urban gaps but also complementing the core channel INSIGHT China Maybe But Russia NowEutelsat and Intersputnik, the International Organisation of Space Communications, have signed a long-term agreement for 16 transponders at Eutelsats 36 degrees East video neighbourhood. Valid for the entire on-orbit life of W7, which has been co-positioned with W4, it will guarantee longterm capacity for digital TV and broadband services in Russia.The deal will provide new resources for the Gazprom Media Group, which operates the DTH platforms NTV Plus and Tricolor. With co-location of W4 and W7, Eutelsat has effectively doubled its broadcasting capability at 36 degrees East, which covers Russia and Ukraine.

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SatMagazine February 201019 similar chip-based battery driven device markets, remembering antenna, are currently and Spain. Ondas Media is seen by most as being a strong contender in this space and already has contracts signed Renault, BMW and Nissan. SMS-type short messages to be sent directly from a vehicle up to the satellite. Transmission but the technicians say it looking to see standards open standard for this aspect of the technology. Mr. de Rosen has strong praise for former in June last year, and it old vision focused on telephony into a productivity. Not all companies have this INSIGHT

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SatMagazine February 201020 enterprising spirit and it is a remarkable achievement. The commercial, financial and operational metrics of a private the company. We are lean, dynamic and fast to adopt a good idea. Unless you better to build and rely on a strong team group of people to be a real team, that is be the best. Bankers often visit us and say INSIGHT And More Biz For AfricaEutelsat signed a fresh contract with Multichoice Africa that covers 20 transponders on Eutelsats W7 craft (36 deg E). It is one of Eutelsats largest-ever deals, and represents a new 6-transponder extension to the current contract, and also a time extension. Multichoice already uses Eutelsats W4 craft at 36 deg E, and services are being currently transferred to W7. This 15-year agreement extends the relationship to 2025.With the move to W7, MultiChoice Africa has consolidated all of its Ku-band pay-TV activity outside Southern Africa onto one Eutelsat satellite. In addition to benefiting from better signal levels and improved coverage for all the regions already served from Eutelsats 36 degrees East neighbourhood, MultiChoice Africa has extended its Ku-band service to additional countries, notably Ethiopia, which has been receiving DStv in C-band, requiring large domestic antennas.

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SatMagazine February 201021 a compelling reason for Eutelsat to be global in terms of creating real value for the company and its shareholders. Eastern Europe, the Middle East and current prices, potential price evolution, competitive landscape and of course realistic opportunities. With such an approach, the East looks more interesting De Rosen enthusiastically about the upcoming launch of Ka-Sat, later this year. He said from the market is to believe in the Tooway distributors clear evidence that people need satellite resources for broadband. to be at this time. We are active in all our pressure on our colleagues to do more, While being perhaps deliberately vague about his immediate plans geographically, De Rosen spoke enthusiastically about generally. He and Mr Berretta had recently received, he added. He commented this is the result of years Eutelsat top management and Chinese authorities. But he said there is more a real presence in Asia and to then implement a plan. Eutelsat, amongst ProtoStar-1 the sluggishness in many individual markets and surplus of capacity leading Mr. de Rosen of revenues looks certain to pass through the 1 billion euros mark this year. Video percent. But data and broadband traffic is also

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SatMagazine February 201022 usage clients-generated revenues of of our businesses and geographic position, he remained firmly of the business and generate solid revenues by the mid-term life of the satellite. Mr. de Rosen interestingly joked that even some admit. He is on record as saying that, as percent of a satellite, and his statement (Editors Note: The March issue of SatMagazine will offer a number of articles dealing with SatBroadcasting, including 3DTV, and Chris exam of the latest 3D happenings at CES, which occurred earlier this year in Las Vegas.) INSIGHT About the authorLondon-based Chris broadcasting journalist. He reports on all aspects of the TV industry emphasis on content, the business television and emerging technologies. This includes interactive multi-media and the digitized content over all delivery platforms including cable, satellite and digital terrestrial TV mobile. Chris has been investigating, researching and reporting on the

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SatMagazine February 201025 INSIGHTLong before the term recycle became the buzzword of the times, peddlers of pre-owned satcom equipment were scouring the planet in search of post-warranty treasure bargainpriced system components scarred from years of faithful service, but with some operational time presumed to still be left on the clock. ew Or Used? The Chronicles Of SATCOMNRADFORD

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SatMagazine February 201026 INSIGHT Vast inventories of potential harvests of teleports unable to survive fierce competition and turbulent markets, and like hungry buzzards circling high above desert steer doomed to a drink-less fate, final gasp a death knell preceding the inescapable finality of liquidation. millions of hours (by the manufacturers of course), satcom products had a propensity to outlive the life spans of the purchased. This created the opportunity to resurrect dormant craftsmanship so it could once again generate precious plan and yield huge savings for architects desiring to build Earth stations on the cheap, or in days instead of months.Despite the promise of these obvious practice, but history has obvious value proposition. an unscrupulous broker, deceived, oversold, and ultimately betrayed, by a for a charismatic purveyor of tongued serpent possessed an inane talent for looking one straight in the eye and undeliverable promises.

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SatMagazine February 201027 INSIGHTDale Carnegie himself, this convincing disaster and emotional distress. had the immediate need my list of deliverables schedule pressure to meet a critical uplink, the long lead-time for antenna threatened our impending disaster. Boy, While perusing the advertisements in a popular industry an ad promising huge inventories of quality, used equipment ready for immediate delivery. Being skeptical to say the least.But a guided tour revealed a seemingly de-commissioned Earth station components piled about like Lego blocks ready to be actually visualize the end to a history of long deliveries and high prices.

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SatMagazine February 201028 Like an oil-soaked puffin flapping Valdez and drifting aimlessly into the customer under immense pressure to get a satellite link established and identifying INSIGHT Rescue A RelicThough delivery of the equipment to 11 meter feed equals one unusable pile of scrap metal. To quote the installers on though deathly long delivery. and the broker slithered back under the heard from again. Though permanently a demonic soul sculpted by forces of create a positive result. be entered into the Chronicles have lived it. A testimonial intended might be forced to navigate should the necessary due-diligence not be done Tony RadfordThe moral of this story is simple. The availability and brokerage of quality used equipment has a distinct and quantifiable value to the industry. When purchased through a reputable broker, great deals can be had, schedules reduced and savings realized. Quality brokers are out there vying to keep rescue a relic. After really more fun?

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SatMagazine February 201031 FOCUSNotwithstanding the current economic climate, air transport is forecast to double by 2025 according to the latest Eurocontrol figures. And it is abundantly clear that current air traffic management (ATM) systems around the world will simply not be able to cope. To address this issue, as well as issues of safety and security, there are a number of he Future Of Air Traffic Management CommunicationsTTRIAGNOSYS

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strategic government-funded projects develop the most appropriate and techniques for the future needs of ATM. Theses include the Transportation System ( NextGen ) in the US and Single European Sky ATM Research (SESAR) in the European Union.The overarching objective of these projects is the more efficient use of available airspace, without compromising on safety. A key enabler of many of the required changes is improved communications between air traffic controllers and pilots. That inevitably will mean increased, and smarter, use of satellite communications. Communication between controllers and pilots has, for many years, used VHF, or for longer range HF, voice communications. Both have limitations that will only be exacerbated as air traffic volumes increase. HF, for instance, does enable long-range communication, but certainly does not provide the comprehensive global coverage of which satellite communications is capable. An additional limitation of the existing technology is that as controllers currently use a single frequency, and when a sector is very FOCUSFigure 1: Visualization of the NEWSKY seamless satellite/terrestrial link handover demonstration

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SatMagazine February 201033 busy, many pilots will be listening to the same signals, which can, and occasionally does, lead to confusion. The latter limitation is already being addressed by the introduction of Controller Pilot Data Link Communications (CPDLC ). It enables air traffic controllers and pilots to communicate using pro forma data messages, to avoid confusion and save time, though of course the system also allows for free text entry when necessary. NEWSKY NexGen ATMThe next generation of ATM technology will be based on Internet technology, the use of both satellite and terrestrial communications, and the interface between them. This is an area in which the European Union is taking a lead, in particular through NEWSKY, an EU-funded research project that has recently come to a conclusion, and in which TriaGnoSys, the expert in satellite-based communications and information transfer, was responsible for the development of the relevant satellite and terrestrial communications solutions, and the handover processes between the two.As proof of concept of the NEWSKY project, a simulated flight was conducted between Europe and the US at the projects final presentation in October 2009 at the German Aerospace Centre. The three phase simulation over European, oceanic and North American airspace involved testing both voice and data connectivity between pilots and controllers, to deliver continuous, seamless communications throughout the three key phases of the flight. Weather maps and CPDLC-like data messages were also transmitted over the links. FOCUS

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The first phase was in European airspace. Both terrestrial and satellite (Inmarsat BGAN, in this case) radio links were available and either could be selected, based on the programmed link selection rules. The rules are based on a number of factors, including the availability of a specific satellite link, efficiency of the terrestrial radio link which depends on, among other factors, the weather and indeed cost.The second phase of the flight was over oceanic airspace, where only satellite connectivity was available. The simulation demonstrated the seamless automatic handover from the terrestrial network without loss of session continuity. The third and final phase was over North American airspace. As with the first phase, the link selection rules governed which link to use, again with automatic handover. FOCUS Figure 2: NEWSKY ATM testbed architecture

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SatMagazine February 201035 ATM technology is central to the NEWSKY research. The full name is Networking the Sky for Aeronautical Communications, and the concept was the integration of a range of applications, using Internet Protocol version 6 (IPv6) as the basis. In addition to the key air traffic control (ATC) communications, other applications include airline operation communications, airline administrative correspondence, and passenger communications. One of the key considerations for the use of IP is that is combines high reliability, cost savings, and an optimal alignment with the evolution of communication and security technologies through the use of Commercial(COTS ) solutions. Also, the focus has been on a move away from proprietary software, to allow wide access. In addition, since this system is based on IPv6 for future-proofing, it is backwards compatible with IPv4. In short, every business uses IP, making it the obvious candidate for the next generation of ATM communications. Cost remains a key factor in the development of air traffic technology, course, it is not as important as reliability, and safety is the overriding consideration of the decision-making process in both the public and private sectors. FOCUS communications for ATM have been provides the most efficient satellite use of satellite payload, brings satellite usage VoCeM, as the name suggests, cuts the an idea of the scale of savings provided so much attention, is actually even more only 3.3 kbit/sec, including all overheads. header compression, voice transcoding The three main elements of the technology are:First, the voice payload is transcoded for transmission with a new AMBE2+ codec (Advanced Multi-Band Excitation), providing significant bandwidth efficiencies without compromising quality. Figure 3: Cost Savings Using VoCeM

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SatMagazine February 201036 Secondly, each header is compressed to the minimum servers to reconnect the information in the correct way). VoCeM removes all redundant headers and compresses the useful ones. Finally, VoCeM uses multiplexing to bundle a number of voice payloads together, to form a single packet, further reducing the headers required.The key benefit this technology provides is cost saving. Based on current satellite VoCeM can provide: FOCUSFurthermore, quality is not compromised. Telecoms providers use a scale of zero to increasingly important role in ATM, not available. As efficiency and safety unacceptable for aircraft to be out of touch at any point during the flight, and satellite costs are reduced, ATM services using satellite links are the future.

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SatMagazine February 201037 About the authorDr. Markus Werner is one of the founders of TriaGnoSys. He received a Dipl.in electrical engineering. Markus received and teaches satellite communications courses for telecommunications professionals.

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EVENTThis important broadcasting through Digital Broadcasting runs from March 2nd through 4th and will provide high level information and real-life experiences for those involved digital radio, and file based production industries. Speakers from MENA and around the world will offer attendees their invaluable expertise. This is a platform for broadcasters and other industry players to exchange views and experiences on launching and supporting CABSAT MENA 2010Valuable + Free To Attend!

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SatMagazine February 201039

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SatMagazine February 201040 New Compression Technologies Building Network Infrastructure File-based Production Workflow File-based Production for Radio Implementing Digital Broadcasting: Network Planning Broadcasting Middle East Implementing Content Protection Technologies and IPTV in the MENA region Transmitting Facility Infrastructure Also free to attend during this conference is the GVF MENASAT Summit The Middle East and North Africa Satellite Summit is themed Development Dynamics in Wireless Applications Market.The GVF Summit, held on March 3rd, brings together industry leaders to identify and discuss the development and satellite-hybrid services and communication technology users, operators, manufacturers and analysts, opportunity for the MENA region. The Summit highlights include...The MENA Communications Market Panorama Understanding Unified Value Chain OpportunitiesMENA Industry and Government as Satellite Service Customer Application Focus Regional End-User Vertical Market FocusTechnology Focus CABSAT MENA has become digital media industry. CABSAT MENA is to gain an edge over their competitors, all the more so in the MENASA region, face to face relationships are critical to successful business dealings. The event and services from the entire spectrum of digital media from content creation to management to delivery. response to the increasing demand of the satellite industry. Satellite MENA is the first ever definitive event of its kind in the region, serving broadcasters, commercial entities, telecoms operators, government, Satellite MENA aims to be the industry opportunities, formulate strategies and create partnerships for video, voice, data EVENT

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EVENTAustralasia Oil & Gas Staged in the city of Perth, AOG 2010 is held annually and has run for over a quarter of a century international petroleum expo, showcasing the latest technical challenges and solutions connected with oil and gas exploration, production, and transportation. The entire spectrum of the industry is covered, from exploration and production technology to gas processing, pipelines, communications and more.Premiere Industry Exposition

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SatMagazine February 201042 EVENTAOG is the place -To source new products + services To compare new products and supplier offerings To ensure that you select the correct products and services for your business To keep abreast of the latest launches to free seminars on the show floor AOG is a showcase for new innovations attendance this is your opportunity to assess all solutions in an impartial environment.Plan to attend the Subsea Australasia Conference, Health & Safety or Carbon Storage Seminars. At AOG 2010, communication companies participating PacTel International. The director of the company, r, believes this is a great opportunity for the Company to present their range of telecommunications Stand Y22. Appointments can be made prior to efficient as possible. Pactel International was co-founded in 2003 by Andrew Taylor and Steffen Holzt, both with more than 20 years of experience in the satellite and telecommunications industry. Andrew worked in various commercial and engineering roles at PanAmSat, Comsyst, Optus, and Telstra. Steffen started his career in satellite communications in the Pacific Islands. In 2000, he founded Pacific IP Services in New Caledonia, which merged into Pactel International.Pactel International focuses on satellite telecommunications and broadcast services within the Asia-Pacific Region. Company services include Internet backbone connectivity, VSAT data solutions, VOIP gateways, broadcast and streaming video solutions, international private leased line, equipment hosting as well as satellite ground system and network design.The Company focus is on high quality, customized and affordable telecommunications solutions for the telecommunications carriers, ISPs, government organizations, Mining, Oil & Gas industries, broadcasters and businesses that have a need for dedicated solutions to meet their connectivity challenges. With the head office in Sydney, Australia, and regional offices in the Pacific Islands, Pactel International offers support to all of their customers who live and work in similar time zones. Pactel International works closely with their customers and adopts a hands-on approach during the design, implementation, and delivery of all solutions.The Company implements fully customized solutions to match their customers specific telecommunications needs; from point to point links through to fully managed networks all receive the highest quality solutions at extremely competitive rates. What sets Pactel International apart is their expertise in using satellitebased technologies to provide telecommunications solutions at highly competitive rates.

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ombatting Satellite InterferenceCINTELSAT FOCUSFor decades, the satellite industry has achieved steady growth by meeting end-user demand for reliable, cost-effective communications for a wide variety of applications. Each day, thousands of corporations, broadcasters, government agencies and other organizations worldwide depend upon immediate access to satellite networks for Internet

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SatMagazine February 201046 connectivity, video conferencing, LAN/ WAN interconnections, distance learning, Radio(RFI ) has become a critical threat to satellite reported each year create obstacles for daily operations. Ultimately, end television signals, data transmissions and other customer services To promote an interference-free space environment, Intelsat recently launched the ( I3 data and communications alerts are implemented to focused on enhancing customer and operationmaintaining an interferencefree space environment is to actively provide the means to responsibly access global satellite interference for other users. To meet to train VSAT installers and satellite Training For VSAT Installers training from the Global VSAT Forum (GVF) training and certification program. The GVF courses educate technicians on proper equipment installation and FOCUS

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SatMagazine February 201047 customer technicians to be trained. discount on training for organizations based in developing countries. The discounted rate is part of the Scholarship Program. Certification training program has served as the industry-standard since been continually updated a combination of online, interactive, simulatordriven training modules and formal hands-on skills testing all managed through the GVF training portal at www.gvf. coursehost.com. Hands-on skills testing and supplementary classroom sessions are supported by GVF instructors and regional The training program has recently been upgraded to specifically reinforce core skills that field technicians need to prevent accidental uplink interference. GVF510 (Core Skills for Satellite Technicians) online course includes intensive instruction and practice using 3-D simulators. Upon completion of FOCUS

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the course, and demonstration of their GVF Basic VSAT Installer Certification. The certification indicates that a technician understands the importance of interference mitigation and has the skills to minimize interference Training For SNG Field Operators number of sessions on BeaconSeek SlingPath SNG online training program. After evaluating a number of training Jazeera and Arqiva, among others, have successfully completed the SlingPath training. We believe SlingPath is ideally FOCUS requirements of SNG field operators. supporting our customers by facilitating this training course at a reduced rate.Improving Industry-Wide QoS These include the establishment of a Carrier ID System operators and the Satellite User Interference Reduction Group ( SUIRG),

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SatMagazine February 201049 FOCUS a satellite has an embedded identification the emergency contact information of the interference source to satellite operators, resolve the interference incident. Data Sharing Program is imperative for numerous critical satellite operator procedures, including operators can standardize, formalize and automate these procedures. Satellite Operator RFI Alert Network and suspect that the interfering signal may be from a source outside their to reduce the duration of customersatellite operators, manufacturers, industry organizations and end-users must prioritize interference mitigation and ensure that field technicians and engineers have appropriate skills. By sharing critical information on interference incidents and resolutions, and properly training technicians, the satellite and end-user communities can of end-user operations and continued global satellite communications. About the author is responsible for managing terrestrial and space-segment operations encompassing Customer Systems Management and Planning, and all phases of spacecraft development, launch and operations. Canyon University

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SatMagazine February 201050 For many years, GVF has provided comprehensive skills training to thousands of VSAT technicians worldwide. To accomplish this, GVF uses online, interactive training to deliver a sequence of VSAT installation certification courses. The basic course teaches the core skills that are critical for satellite interference prevention. Optional, follow-on courses cover advanced theory, practical techniques, and specialized training for specific terminals.Each student is assigned a private account on the GVF Learning Management System (LMS). After logging in, the student steps through the lessons at their own pace. Each lesson concludes with a quiz and, in certain cases, a simulator skills assessment. There is a comprehensive exam at the end of each course and downloadable reference materials are provided. Students who need extra time to study new materials are welcome to linger. However, if they encounter topics with which they are already familiar, they can move through the courses more quickly. Flash-based simulators provide realistic, critical skills practice with features that go beyond what is possible in a classroom. For example, the antenna-pointing simulator uses an interactive 3D model of an actual VSAT antenna. The student must learn the functions of all the bolts and fasteners, place a wrench on the right ones at the right times, and make real adjustments. The 3D graphic is updated as the student turns azimuth, elevation, etc. Behind the scenes, the software computes link budget updates, antenna beam patterns, mechanical backlash and lock-down shifts, and true meter behavior based on C/N. Not only is the simulation realistic, it can report details that cannot easily be seen on a real antenna such as true pointing accuracy and graphical depiction of the beam and satellites in the sky.No special Internet connection or PC hardware or software is required for these online courses. Certification concludes with a hands-on skills test, offered by GVF-qualified examiners worldwide. The screen shot below illustrates the dish-pointing skills exercise from the GVF Core Skills for VSAT Technicians course.The GVF Method

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SatMagazine February 201051 Basic SNG Operations is the initial SlingPath satellite newsgathering (SNG) course aimed at the absolute beginner. It takes the student through satellite basics, including how satellites are used in newsgathering. The course outlines the theory of critical SNG system component parts, various key technical parameters, and operational procedures with satellite operators including the risk of causing interference, and how to work safely in the field. The presentation of the training is user-friendly, highly graphical, and interactive with even the most complex subjects presented in an approachable fashion. Once a student has enrolled, all the training is accessed through a web browser. There are no DVDs or training manuals sent out to the student. Anyone in the world with the most basic Internet connection can access this state-of-the-art course. The student logs in with their unique username and password to access the course at any time to suit their schedule. It is comprised of seven modules, with a self-check test at the end of each module. Each time the student logs off, their position is stored. When the student logs back in, they can choose to resume where they last left off, or jump to a different module. Most importantly, after completion of all seven modules (completion is defined as having attempted the self-check test at the end of every module), there is a multiple-choice exam the student must pass with a score of 80 percent in order to be awarded the Final Certificate. The student can attempt the modules and the examination as many times as they wish (though the questions randomly change each time) over the 12-month life of the training seat. The normal price of the training seat is US$595.The screenshot to the left is from the SlingPath Basic SNG Operations training and is an overview summarizing the TV signal uplink process.The SlingPath Method

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SatMagazine February 201053 FOCUS WISE ProjectAJET PROPULSION LABUnited Launch Alliance capped 2009 with the launch of a Delta II Infrared Survey Explorer (WISE) spacecraft at 6:09 a.m. PST, on Thursday, December the 17th. Rocketing from Space Launch Complex-2, the launch was the eighth Delta II during 2009 and represents the 37th successful mission launched by ULA in its first 36 months of operation.

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SatMagazine February 201054 FOCUS hundreds of times greater than ever of hundreds of millions of objects and producing millions of images. The darkest near-Earth asteroids and comets. Delta II 7320-10C configuration vehicle featuring a ULA first stage booster by a Pratt & Whitney Rocketdyne RS-27A main engine and three Alliant Techsystems solid rocket motors. An Aerojet AJ10118K engine second stage. The payload diameter composite payload fairing.Mission OverviewThe Wide-field Infrared Survey Explorer, or WISE sky in infrared light, picking up the and producing millions of images. The before, including the coolest stars, and some of the darkest near-Earth about the origins of planets, stars of data for astronomers to mine for decades to come. greater than its predecessor, the Infrared Astronomical Satellite in space Spitzer Space Telescope and the Observatory, a European Space Agency all sorts of unseen cosmic treasures, including rare oddities. near-Earth objects, both asteroids and bodies, and hundreds of thousands of main asteroid belt. By measuring the get the first good estimate of the size

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SatMagazine February 201055 FOCUSdistribution of the asteroid population. about the composition of near-Earth objects and asteroids are they fluffy These Jupiter-like balls of gas form like stars but fail to gather up enough mass to ignite like stars.The objects are cool and faint, and nearly impossible to see in or ULIRGs the distant universe, but appear virtually should find millions of ultra-luminous

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SatMagazine February 201056 of these could be the most luminous stars; disks of planetary debris around young stars; a detailed look at the and more. The most interesting Spitzer Space Telescope, the Observatory TelescopeSOFIA James Webb Space Telescope the most surprising finds to come out infrared light around familiar stars like Vega and Fomalhaut. Astronomers soon from pulverized rock in disks of planetary debris. The findings implied that rocky planets like Earth could be common. Today hundreds of astronomers study these debris disks, and Hubble recently captured an actual photograph of a planet orbiting Fomalhaut kilometers (326 miles), circling Earth via the poles about 15 times a day. snapshots can be taken every 11 seconds over the entire sky. Each position on the and detectors are kept chilled inside a Thermos-like tank of solid hydrogen, from picking up the heat, or infrared, After a one-month checkout period, then begin a second scan to uncover even more objects and to look for any changes in the sky that might have occurred since the first survey. This frozen-hydrogen cryogen runs out. Data months after the end of the survey, or about 16 months after launch, and a months after launch. FOCUS

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SatMagazine February 201057 FOCUSMission Operations includes all facilities required to operate the satellite; acquire its telemetry; and process, distribute and archive data products. JPL is responsible for all ground operations that track and control the spacecraft. from a sun-synchronous around the poles at the to night, called the terminator. The orbit is designed to precess, that it stays over this line. This ensures that continuously soak up the snaps images of the sky overhead, mapping each orbit. As Earth orbits around the sun, these strips of images Adjustments are made every half orbit to keep the telescope pointed at the correct strip of sky, in advance. Surveying is interrupted four times a day to transmit images to the ground via the Tracking and Data Relay Satellite System data to a ground station at White Sands,

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SatMagazine February 201058 and some telemetry data are transferred to the at the at Caltech.Science Data Processing + Archiving converts them into high-quality images be archived and distributed to the user Science Goals + Objectives vastly improved sensitivity and resolution over past missions. All-sky surveys are interest, and, in some instances, have opened up entire fields of study. Many modern surveys have combed the sky successful Infrared Astronomical Satellite microns is from the Cosmic Background Explorer hundreds of millions of space objects. Like scanning the grains of sand on a endure for decades to come. and catch objects that have changed relatively nearby. The science goals of the mission are:To find the nearest and coolest stars To find the most luminous galaxies in the universe To find and study asteroids in our solar system To better understand the evolution of planets, stars and galaxiesOther Goodies including thousands of dusty, planetFOCUS

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SatMagazine February 201059 piece together the evolution of stars and came to be. its first look at the starry surveying in infrared as navigation charts for other missions such Spitzer Space Telescopes, pointing them to the most interesting targets shortly after the space starlight for the first time. This direct link will reveal the picture, which shows 3,000 stars in the Carina constellation. The image covers a patch of sky about three times larger than the full moon. because it does not contain any unusually could damage instrument detectors if observed for The Spacecraft FOCUS

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SatMagazine February 201060 the spacecraft bus. The Space Dynamics Laboratory in Logan, Utah, designed, fabricated and tested the instrument, (16-inch) telescope and four infrared each, all kept cold inside an outer frozen hydrogen, called a cryostat. a giant Thermos see a resemblance to the Star Wars robot R2-D2. After launch, the hydrogen vents on the cryostat are opened and the instrument cover is ejected. have occurred, a scan mirror in the only moving part in the instrument.At the bottom of the instrument stabilized, eightsided spacecraft bus that houses the computers, electronics, battery needed to keep the observatory operating and oriented correctly trackers for precision FOCUS

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SatMagazine February 201061 pointing are mounted on the sides of is mounted on one side of the bus, and a science images to the ground is mounted on the opposite side. The bus structure is composed of aluminum honeycomb panels deployable parts the only moving parts are to turn the satellite.The base of the spacecraft structure system of springs to reduce stress from the rocket on the satellite. A metal clamp band attaches the second stage of the rocket to the base of the satellite, and spacecraft to separate from the launch vehicle once in orbit.Command + Data HandlingThe command and data handling system brain, responsible for monitoring and controlling all spacecraft Spacecraft Control Avionics the Southwest Research Institute a single-board RAD750 computer, memory, a command and telemetry interface, an instrument interface, FOCUS

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SatMagazine February 201062 a flash memory card and spacecraft handles engineering and science data to be sent to Earth.Electric Power hit the solar panel properly, the satellite facing the sun and the instrument pointed by Spectrolabs, Sylmar, California. The Attitude Determination and Control The spacecraft attitude determination and control system is used to adjust the of a complementary set of four reaction Momentum build-up in the reaction sensors provide measurements of the visible-light electronic cameras called charge-coupled devices (CCDs). They are capable of acquiring, tracking and identifying multiple stars in their fields pointed in different directions, so that, measurements from one star tracker, the other one can be used. Ball Aerospace & Technologies Corp. manufactured the CT-633 star trackers.Telecommunications Tracking Data Relay Satellite System day, an average of 15 minutes each time, the poles every orbit, the survey can be the all-sky map.The NASA satellites relay the spacecraft health and science data to a ground From there the spacecraft telemetry is sent to JPL, and the science data to the at Caltech. FOCUS

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The NASA satellites also relay commands using four omni-directional antennas on receive commands from the ground at either four or 16 kilobits per second.Flight SoftwareThe observatory uses stored commands to perform its normal operations and also receives commands and sequences computer translates the stored and ground commands into actions for various spacecraft subsystems. The for all parts of the spacecraft and continuously monitors the health and safety of the observatory. The of autonomous functions, such as attitude control and fault protection, problem has occurred. perform a number of preset actions to resolve the problem or put the spacecraft in a safe mode until ground controllers can respond.Thermal Control SystemThe spacecraft is protected by an onboard thermal control system that consists primarily of passive elements: multilayer insulation blankets, radiator panels, thermal coatings and finishes. heaters provide precise temperature camera and scan mirror electronics, maintaining electronics above survival temperatures in contingency modes.Science Instrument diameter (16-inch) aperture and is designed to continuously image broad FOCUS

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SatMagazine February 201064 a-half times the diameter of the moon.L-3 SSG-Tinsley in Wilmington, all made of aluminum and coated in gold to improve their ability to reflect infrared light. Four of the mirrors form mirror onto the flat scan mirror. The cancels the changing direction of the frame images to be taken every 11 seconds. The scan mirror then snaps continues to survey the sky.The remaining mirrors form a focused image of the sky onto the detector arrays. Before reaching the arrays, the light passes through a series of images of the same part of the sky at The image quality, or resolution, of that it can distinguish features one microns, the resolution is 12 arcseconds, or one three-hundredth of a degree. Astronomical Satellite could at 12 and 25 microns, and many hundred times Detectors over past infrared survey missions. The convert light to electrons using an alloy made of mercury, cadmium and tellurium. The electrons from each of the millionevery 1.1 seconds, and the result sent to the instrument electronics. These detector 1RG Teledyne Imaging Sensors Camarillo, Californnia. of the instrument to improve their performance. The 12and 22-micron readout electronics specially developed DRS Sensors & Targeting Systems, Cypress, California. FOCUS

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SatMagazine February 201065 Cryostat radiation from cool objects, the telescope and detectors must be kept at even colder temperatures to avoid picking up their the detectors for the 12and 22-micron (minus 265 degrees Celsius or minus detectors operate at a comparatively To maintain these temperatures, the telescope and detectors are housed giant Thermos bottle. The cryostat is from the detectors -its insulating Lockheed Martin Advanced Technology Center colder, or primary cryogen tank, the and 22-micron detector arrays. To achieve primary tank from nearly all the heat from degrees Fahrenheit). This secondary tank popsicle. A deployable aperture cover ground to prevent air from getting in. sent to eject the aperture cover. Three FOCUS

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SatMagazine February 201066 the spacecraft by a set of springs. An aperture shade is mounted at the top of the telescope to shield the open cryostat sky, this is enough cryogen to complete one-and-a-half surveys of the entire sky after a one-month checkout period in orbit.NASAs Explorer Program Explorer Program Explorer 1 launch in Cosmic Background Explorer (COBE) Mission. managed by JPL for the U.S. Army. The provide frequent flight opportunities for science missions led by a principal investigator and occur over relatively short periods of time. They are selected via a highly competitive announcement of opportunity process. The program currently administers only principal investigator-led heliophysics and astrophysics science investigations; in the past, it covered more fields of science. for space science and to incorporate educational and public outreach activities as integral parts of space science investigations. independent, but share a common funding and NASA oversight management structure. The program is designed to accomplish high-quality scientific investigations using innovative, streamlined and efficient contain mission cost through commitment to, and control of, design, development and operations costs. the Heliophysics DivisionScience Mission Directorate. The Goddard Space Flight Center in Greenbelt, Maryland.Jet Propulsion Laboratory, is at UCLA. The office is based at the University of California, Berkeley. NASA for their invaluable contributions in authoring this article. FOCUS

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W

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SatMagazine February 201069 TECH CHANNEL hat Is Network Latency Why Does It Matter? WO3b NetworksInternet data is packaged and transported in small pieces of data. The flow of these small pieces of data directly affects a When data packets arrive in a smooth and timely manner the user sees a continuous flow of data; if data packets arrive with large and variable delays experience is degraded.

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SatMagazine February 201070 TECH CHANNELWhat Is Latency?According to Wikipedia, latency is a time is initiated, and the moment one of its effects begins or becomes detectable. The period of latency the effects of an action of latency. time delay imparted by each element involved in the transmission of data.Networking 101 properly grasp the latency issue. Early need to be able to handle thousands to millions of users on one cohesive The key design feature of the TCP/ container for shipping. The container that IP Datagram IP Packet.header, data. The Header contains information used for routing the packet to the destination. The data can be any information that needs to be transported such as a snippet of streaming music Packet is defined by the data protocol that is being carried. Data protocols OSI Model: process of turning your application data into something that can be transported on the computer. These applications are

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SatMagazine February 201071 TECH CHANNEL to and from applications are turned into the TCP/IP Stack various computer operating systems. These differences may seem trivial as long as the protocols are implemented implementation can be a significant cause step process: Data from a source application 1. is passed down through the stack. During this process the application data is wrapped into IP Datagrams which are commonly called packets. Packets are then transmitted by the sending computer in the network. Packets are passed along the 2. network (purple line) until they reach the destination computer. Packets are received from the 3. network by the destination computer and are passed up through the stack. During this process the application data is extracted and then passed along to the destination application.The additional encapsulation at Layer 2 is called framing This is the stage Layer 1 medium connection. This layer handles the conversion of the layer 2 bits into electrical, optical, or radio signals that can be transported. The NIC or Network Interface Card, can be radio interface.

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SatMagazine February 201072 What Causes Latency?As described above there are many logical, electrical, and physical elements model identifies each of these elements delays, another name for latency, occur at every stage of the process.Application Layer LatencyLayer 7, 6, 5 the processor or the efficiency of the to manipulate and present data. source of application latency is the need application performance such as the amount of memory.Serialization Latencies at the Transport Layers called serialization. Serialization takes a finite amount of time and is calculated For example: Serialization of a 1500 byte packet used on a 56K modem link will take 214 milliseconds Serialization of the same 1500 byte packet on a 100 MBps LAN will take 120 microseconds Serialization can represent a significant transmission rates, but for most links this delay is a tiny fraction of the overall contributors.Data Protocols + Latency layers range from simple to advanced. Many transport protocols use information to ascertain link performance and attempt to adapt to specific conditions present on be addressed later in this article.Routing + Switching Latencies to be passed from Point A to Point B. Serialization delay = packet size in bits / transmission rate in bits per second TECH CHANNEL

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SatMagazine February 201073 that are interconnected by links such as algorithms to continuously update their one to get the packet to its destination. congestion along the path, can change the traffic induces delays (latencies) caused by This refers to the amount of processing a packet, process it and transmit it on nanoseconds and are generally negligible latency tends to contribute only 5 percent of the end to end delay for the average Queuing + Buffer Management over-use of the outgoing link after the While over-utilization of high-speed instances of congestion are common on When congestion occurs, routers use sophisticated data queue management algorithms such as WRED (Weighted Random Early Detection) to minimize data loss. Congestion can cause queuing delays to become infinite since packets full. Queuing algorithms use a variety of packet management schemes to ensure queuing latency is minimized; best common practice WRED configurations What Is Propagation Delay?Propagation delay is a phenomenon the medium cause the transmitted the velocity factor ( VF). Most people are fiber-optic cables have similar velocity factors. Fiber optic cables typically construct. many types have a VF of 66 percent. TECH CHANNEL

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SatMagazine February 201074 Satellite communication links use information. The information is converted from electrical signals to radio signals using a modem (modulator/demodulator). antenna, they travel at the speed of light. to London is the great circle distance caused only by propagation delays in the only one sending one single data bit and delayed by the propagation delay. This amount of data being transmitted, the transmission rate, the protocol being used, or any link impairment. Propagation delay = distance/speed: These are the latencies caused only by propagation delays in the transmission sending one single data bit and you delayed by the propagation delay. This amount of data being transmitted, the transmission rate, the protocol being used, or any link impairment.Transmission Rate + BandwidthTransmission Rate is a term used to Transmission rate is commonly measured as the nuMBer of bits measured over a medium if the medium is a copper These rates are primarily limited by the properties and construction of the copper TECH CHANNEL

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SatMagazine February 201075 interface card are also a factor. Even the Fiber-optic transmission rates range from limiting fiber-optic transmission rates is end of the fiber.Wireless LANs and satellite links use a modem (modulator/demodulator) to convert then convert the signal back into bits. The limiting factor in radio-based links is the Radio Bandwidth occupy radio spectrum. Radio spectrum is not an unlimited resource and as such must be shared. To prevent radio radio spectrum is controlled by nearly every government on the planet. The amount of radio spectrum occupied by any given radio signal is called its bandwidth.The nature of radio spectrum use is understand that generally the occupied the modem to occupy more radio bandwidth Lower modem data rates will let the modem occupy less radio bandwidthAs radio spectrum is a limited resource, satellite links.Data Bandwidth is synonymous to the transmission rate of a data link.A 10 MBps copper LAN cannot sustain traffic flowing at a higher rate than 10 megabits every second A satellite link using modems operating at a 600 MBps rate cannot flow any more than 600 megabits every second obtainable over a given transportation segment over a given period of time.Latency + TCP/IPThe final detail required for on in the transport layer. Recall that TECH CHANNEL

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SatMagazine February 201076 the transport layer is the process of encapsulating application data into connectionless connection based Connectionless data is simply pushed to the destination connectionless packet traverses the but if anything happens to it along the this manner seems risky but depending transporting streaming music, and video, and Voice over IP traffic. The transport protocol commonly used for connectionless traffic is called User Datagram Protocol or UDP. This protocol is popular as there is no overhead or connection management the data is just sent along. There is no retransmission of lost packets because having them arrive late is not useful for voice or video that is being played out in real-time by the receiving computer.Connection are far more complicated. These data is that both the sending and receiving computer applications are very interested in ensuring the integrity of every piece protocol commonly used for connectbased traffic is called the Transmission Control Protocol, or TCP. TCP provides error free sequenced delivery of packets. missing, TCP asks for retransmission. The To support the additional connection management features, TCP packets contain additional information in used throughout the establishment of the connection and are the key to providing control of the connection. TCP connections use a client/server model to describe the sender and receiver of data. necessarily mean a computer performing is listening for TCP connections. TCP connections have three phases:Establish the connection1. Send the data2. Close the collection3. TECH CHANNEL

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SatMagazine February 201077 Phase 1Establishing the connection requires 3 packets...the client sends a connect request SYN (synchronize) packet to the server the server replies with a SYN-ACK (synchronize acknowledge) packet the client confirms the receipt of the SYN-ACK by sending back an ACK (acknowledge)Phase 2 the data transfer can start. ACK NACK types are used to tell the sender that packets have been not received or it contains a bit error, the transmission of the Phase 3Upon completion of the data transport session, the the closing initiator sends a FIN (finish) packet the other side of the link replies with a ACK the closing initiator send a coMBination FIN/ACK to end the connection protect the integrity of the data, TCP packets have several features...Sequence NuMBers TTimestamps Flow Control Congestion Control Checksums All of these features are used to guarantee the integrity of the data. They are also used by TCP to determine the quality of the link and to tune the TCP responds to congestion control. The TCP congestion control process uses longer than normal to respond, TCP assumes that the link is being congested This vital step helps reduce the impact processing limitations. By throttling the output of data when congestion is sensed, the TCP congestion control mechanism plays a key role in the flow of TCP/IP traffic. TECH CHANNEL

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SatMagazine February 201078 Congestion control is generally a valid response does often indicate that a portion of the link has a data bottleneck.A Fictional Data Download actually 32 megabits (32 MB). cannot simply create a 32 MB packet to transport our image; such a large packet of variable sizes, but the Maximum Transport Unit ( MTU) is generally only packets, but handling these is not yet commonplace for many parts of the not useful image data. The size of the Based on the amount of data payload bits per packet. Even this nuMBer can layer formatting of the data, but for this payload is useful image data. normally become shortened instead of our full MTU but to keep the math easy We are downloading the file from a local computer using a 10 Mbps LANThere is no other traffic on that 10 Mbps LAN we get the whole pipeThe link is operating perfectly, no need to repeat any data during this transmissionThere is no appreciable latency. This is a copper LAN and a relatively short cable run which is not adding any appreciable propagation delay Notice that even for a link that is operating perfectly, the transfer of our needs to be transported. This overhead is Activity # packets x packet length Total bytes Total Bits (bytes X 8) Connection setup 3 x 60 bytes 180 1440 Transmit the file 2778 x 1500 bytes 4,167,000 33,336,000 ACK packets 2778 x 60 bytes 166,680 1,333,440 Connection close 3 x 60 bytes 180 1440 Totals 5562 packets 4,334,040 34,672,320 bits TECH CHANNEL

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SatMagazine February 201079 long that should take. This is simple...34.6 Mb/10 Mbps = 3.46 seconds image file in just over 3 seconds.The Real World Assumption 1: The file you want is available on a local computer. Reality 1: The file is more likely to be some physical distance away. This is not necessarily a problem, but it means we need to traverse a much more complicated network path to get to our data. Assumption 2: We get the whole 10 Mbps to ourselves. Reality 2: This is feasible only for the local LAN. It is a certainty that once your little 1500 byte TCP/IP packet reaches the Internet backbone, it will be joined with millions of other packets working their way through the Internet. Your image file packets are going to be mixed in with other traffic such as emails, streaming music files, and so on. You simply dont get the Internet all to yourself.Assumption 3: The link is operating perfectly.Reality 3: Internet traffic is routed through an extremely complex collection of hardware which is scattered all over the Earth. The reality is that sometimes a fiber or copper cable is cut or is mistakenly disconnected. A piece of networking equipment such as a router or a switch can break, leaving some other path to pick up and route the extra traffic. When this happens, Internet traffic can start to fill up queues and bottlenecks occur. As mentioned earlier, queuing delays can become significant when the network is operating through a bottleneck.Assumption 4: There is no appreciable latency present in our network. Reality 4: The reality is that all of the earlier discussed sources of latency are genuine factors in realworld networks. The impact of latency starts to become noticeable when the latency is significantly longer than the transmission time for the data. transmission rate in terms of the number rate into its measure of time.Bit transmission time = 1/(bits per second) TECH CHANNEL

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SatMagazine February 201080 rates take longer to transport packets of same as the bit transmission rate, then the still be streamed very close to each other. become much more noticeable because content from the CNN web page. The only remained the same. Type of Link Time required to transmit 1 bit Time for one 1500 byte packet 14.4 Kbps telephone modem 69 microseconds 823 milliseconds 1 Mbps LAN 1 microsecond 12 milliseconds 10 Mbps LAN 100 nanoseconds 1.2 milliseconds 600 Mbps satellite channel 1.6 nanoseconds 19.2 microseconds The 50 ms latency link took 3 sec The 150 ms latency link took 5 sec The 300 ms latency link took 11 sec The 600 ms latency link tool 17 sec Effective Bandwidth of a link. Packets are still being transported at the same bit rate but due to latency it is taking much more time for all noticeable to the user and creates the impression that a link is not operating at a high speed. O3b recently conducted another page. This is a very common activity and latency on the time to load the Wall Street Journal TECH CHANNEL

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SatMagazine February 201081

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SatMagazine February 201082 Satellite Link Latencies satellite technologies. Satellite links can introduce larger latencies than due to long distances from the ground stations to the satellite. The table on the satellite configurations... The O3b Networks MEO orbit constellation at an altitude of 8063 Kilometers A geosynchronous satellite at 35,786 Kilometers the propagation delays are doubled as the signal has to travel both up to the TECH CHANNEL

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SatMagazine February 201083 in the average internet latency from milliseconds. This range of latency is caused by the change in distance to the the satellite is closest to the customer By comparison, the same Lagos customer site using a geosynchronous satellite to to see latencies of 552 milliseconds. The required to make a data request and to start receiving the requested data. This data request time includes...The request packet from the user to the web serverThe web server acknowledging the requestThe web server pushing to requested data to the user TCP also includes a returned ACK packet from the user to the web server but this time is not counted in the Data Request Cycle. but this time is not counted in the Data Request Cycle. almost 1 second before they start getting TECH CHANNEL

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SatMagazine February 201084 When looking at the basic latency more immediate feedback and quicker access to data.SummaryWe have described the structure of the functions of the various protocol layers, and the causes of latency in Latency and overall throughput is the route that the packets have to take and congestion control protocols and latency than traditional geosynchronous About the company The Company is committed to connecting billion consumers and businesses in headquarters are in St. John, Jersey, technical development are managed TECH CHANNEL

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Advertisers AAE System 37 Advantech 47 CABSAT Mena 2010 39 Comtech EF Data 55 Futron 19 IDGA 23 Integral Systems 17 Miteq / MCL 59 NAB 29 Newtec CY 7 Northern Sky Research (NSR) 13 03b Networks 2 PacTel International 43 Paradise Datacom 21 Singapore Exhibition Services 67 SMi Group 61 Wavestream 27 A SatNews Publishers publication Copyright 2010, SatNews Publishers