Polar Communications Handbook

8/14/2019 Polar Communications Handbook

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Pol eC om

Communicationin Polar Regions


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Communication in Polar Regions 5

A c k n o w l e d g e m e n t s

Thank you for your support!

Maria Bergqvist, Ericsson ResponseDag Nielsen, Ericsson ResponseMark Phillips, Ericsson Response

Sven Lidstrm, Swedish Polar Research SecretariatJohan Sidenmark, Swedish Polar Research Secretariat

Olavi Trydhed, Satellite ConsultantAnders Bjrkman, Swedish Space Corporation Stockholm Teleport

George Falk, IDG Europe

Tom Sjgren, Human Edge Technology

Malcolm Dixeilus

Bjrn Pehrson, Course Director KTHTerrence Brown, Course Director KTHUlla Skidn, KTHTanyingyong Voravit, Coach KTH

Everybody participating in our survey

And everyone else who has contributed to our work

Communication in Polar Regions4

C r o s s - r e f e r e n c e

Iridium 6Inmarsat BGAN 9Inmarsat GAN 10Inmarsat B 12Inmarsat D+ 14Globalstar 16Orbcomm 18Intelsat VSAT 20DVB-RCS 21Argos 22Future satellite constellations 24GPS 25

Satellite data

Iridium 6Inmarsat BGAN 9Inmarsat GAN 10Inmarsat B 12Inmarsat D+ 14Globalstar 16Orbcomm 18Intelsat VSAT 20DVB-RCS 21Argos 22Future satellite constellations 24HF Radio 26WLAN 30WMAN 31GSM 32Microwave links 34

Data

Iridium 6Inmarsat BGAN 9Inmarsat GAN 10

Inmarsat B 12Globalstar 16HF Radio 26VHF Radio 28GSM 32

VoiceInmarsat D+ 14Orbcomm 18Argos 22

GPS 25

Positioning

Photograph by: Sean Loutitt - National Science Foundation


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I r i d i u m


C o m p a n yThe Iridium system was developed by Motorola,aunching the rst satellite on 5 May 1997. After

15 launches a constellation of 66 satellites wasup and running in the orbit and ready for thetart of service in January 1999.

n the rst months of operation, Iridium didnt getenough customers because of the high phoneprice (up to $3 000) and trafc cost (up to $7per minute). Instead, customers chose muchcheaper terrestrial networks such as GSM.

Despite a dramatic price cut in summer of 1999

it was already too late to save the company.Iridium led for bankruptcy in August 1999 andthe satellites were planned to burn up in theEarths atmosphere.

The satellite constellation was saved by a groupof U.S.-based investors who purchased thesystem for 0.5% of its original value. Iridium LLCbecame Iridium Satellite LLC and the companyunderwent reorganization.

According to experts, the satellite constellationwill be viable until 2014 without any additionalsatellite launches.

N e t w o r k Coverage: Truly globalNr of satellites: 66Orbit height: 780 km - Low Earth OrbitOrbit time: 100 minutesInclination: 86.4Frequency: 1.6 GHz (L-band)

T e l e p h o n yVoice bit rate: 2.4 kbit/sServices: Point to point calling

Call forwardingVoice mailSMSPaging

I r i d i u m data

dataD a t aTransmission bit rate: 2.4 kbit/sConnection type: Circuit switchedDelay (up and down): 10 msDownload of 1 MByte: 58 min.Suitable for: E-mail

Transfer of small lesRemote controlling

$

E c o n o m i c sTo land line: 0 .85 - 2 USD/minTo Iridium: Down to half of land priceTo other sat: 10 USD/min or moreSMS: 0.50 USD

For Internet Direct Data it usually costs 50% more than the rate to land lines.

The prices vary with different monthly andpre paid plans provided by different VARs(Value Added Resellers). Lower pricing

may be possible for Africa, USA andCanada. Prices are subject to change.

S u r v e y o f U s e r sSatisfaction:Desire:

Useful, handy, ReliableSome time periods of no coverage

HighHigh


dataS h o r t B u r s t D a t a(for transmission of small messages)Max data amount: 1960 bytes (send)

1890 bytes (receive)Transmission time: < 20 sSuitable for: Remote controlling Automatic tracking

Telemetry reporting

T e c h n o l o g i e s

D i r e c t I n t e r n e t D a t aThis service provides Internet connectivitywithout the need for an ISP. With itstransparent compression of data, speeds ofup to 10 kbit/s can be reached.

A technique called spoong quickly andautomatically connects for data transmissionand disconnects when idle. This reducesconnection time costs, while the connectionappears online all the time.

C o m i n g s e r v i c e sA packet based data service based on ShortBurst Data will be available in late 2005. Theservice will offer a transmission bit rate of 9.6kbit/s.

Push-to-Talk Group Calling (PTT) is a servicefor multiple user communication. It is similar to function of VHF radios. Commercialavailability is planned for 2006.


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I r i d i u m Continued


M u l t i p l e d e v i c e sFor higher transmission speeds, up to 16 Iridiumdevices can be interconnected at 16 times

the cost. Due to synchronization trafc, 4 or 8devices are more cost efcient than 16. Thissolution is called RUDICS.

P r o d u c t s

r i d i u m r e f e r e n c e sBBC, http://news.bbc.co.uk/1/hi/business/681646.stmridium, http://www.iridium.com/

NAL, http://www.nalresearch.com/StandardModems.html

S p e c i f i c a t i o n sIridium 9505A (approx. USD 1400)

Weight: Under 375 gDimensions H x W x D: 158 x 62 x 59 mmAmbient temperature: -10C / +55 CRelative humidity: 93% RH at 40 C

Battery standby: 30 hoursBattery talk time: 3.2 hoursPower consumption: avg. 0.57W

Port interface(s): 1xRS232 data adapter Card interface(s): 1xSIMWireless interface(s ): External antenna

PhoneWith Iridium 9505Aportable satellite phone,you can keep connectedall over the World with

one telephone number,by using a mini personalubscriber identity moduleSIM) card.

t is the only satellite phoneystem that has truly global

coverage.

A data kit is necessary for using the phones built-inmodem.

S p e c i f i c a t i o n sNAL A3LA-DGP (approx. USD 1700)

ModemWeight: 689 gDimensions: 196 mm x 83 mm x 40 mm

Phone

Weight: 200gDimensions: 161 mm x 55 mm x 26 mm

Input Voltage Range: 4.0VDC to 4.8VDCAvg. Standby Current: 680mA @ 4.4VDCAvg. Transmit Current: 1.5A @ 4.4VDCAvg. Call Current: 1.0A @ 4.4VDCPeak Power-Up Current: ~2.7A @ 4.4VDC

Modemwith GPS and Phone

The NAL A3LA-DGPis a combination

of Iridium 9505Asatellite phoneand NAL satellitedata modem with build-in GPS system.

The modem can be controlled by a PC/PDA/micro controller via a serial port.

See www.nalresearch.com for more info.

I n m a r s a t BGAN data


N e t w o r k (future service)Coverage: 85 % of worlds land massNr of satellites: 2 (Inmarsat I-4)Orbit height: 36 000 km

Geostationary Earth OrbitOrbit time: 24 hoursInclination: 0Frequency: L-band (1-2 GHz)

T e l e p h o n yHigh quality 3G supported telephonyServices: Point to point calling

Conference callingCaller IDCall forwardingCall waitingVoice mail

dataD a t aTransmission bit rate: up to 432 kbit/sConnection type: Packet switched

Delay (up and down): 500 msDownload of 1 MByte: 20 sSuitable for: E-mail

Web browsingTransfer of large lesVideo conferencingVideo broadcastVideo store-and-forward

$E c o n o m i c sPrices have not been made ofcial attime of writing. They may speculativelybe similar to R-BGAN prices.

Later this year, another I-4 satellite is plannedto launch to form a global constellation ofthe new generation satellites. Those twosatellites will provide the new BroadbandGlobal Area Network service, which isplanned to be commercially launched inearly 2006.

The rst new service to be launched onthe Inmarsat-4 satellites will be BGAN abroadband-speed mobile satellite servicedelivering data and voice, simultaneouslythrough one device.

Europe, Africa, Asia and Western Australiawill be covered by the rst satellite (F1),followed by coverage in North and SouthAmerica after launch of the second (F2).

The service will be available in Europe, theMiddle East, Africa and Asia in late 2005. InQ2 2006, the service will expand to North

and South America.

As for coverage in Polar Regions Inmarsat,as most other providers, are conservative inguaranteeing service. However, experimentshave shown that there has been GANcoverage a bit outside guaranteed areas,although not around the poles.

Subscribers of Inmarsats Global AreaNetwork (GAN) and mini-M services willget higher levels of network reliabilityand availability through the increase innetwork capacity due to launch of the newsatellites.

Regional BGAN satellite IP modems willcontinue functioning with increasedcoverage in new regions by a softwareupdate, but the bit rate remains the same(144kbit/s). Regional BGAN users will beoffered to upgrade to new terminals.

On 11 March 2005, the rst satellite of thenext generation I-4 satellites was launchedsuccessfully. This is the rst step into the globalmobile satellite broadband communicationera.



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I n m a r s a t GAN data

N e t w o r k Coverage: 98 % of worlds land mass

Spot beam areaNr of satellites: 4 (Inmarsat I-3)Orbit height: 36 000 km

Geostationary Earth OrbitOrbit time: 24 hoursInclination: 0Frequency: 1.6 GHz (L-band)

T e l e p h o n yVoice bit rate: 4.8 kbit/s or 64 kbit/sServices: Point to point calling

Conference callingCall forwardingVoice mailSMS

dataD a t a I S D NTransmission bit rate: 64 kbit/sConnection type: Circuit switched

Delay (up and down): 500 msDownload of 1 MByte: 2.2 min.Suitable for: Transfer of large les

Video conferencingVideo broadcastVideo store-and-forward

dataD a t a M P D STransmission bit rate: up to 64 kbit/sConnection type: Packet switchedDelay (up and down): 500 msDownload of 1 MByte: 2.2 min.Suitable for: E-mail

ChatWeb browsing

$E c o n o m i c sVoice: 2.5 USD/minISDN: 7.8 USD/minMPDS: 35 USD/MByte

Prices are approximate and subjectto change.

The Inmarsat Global Area Network (GAN)combines the IT network with a global mobilecommunication network. It satises the needfor high-bandwidth communication thatenterprises demand.

Global Area Network offers two services- Mobile ISDN and newly launched MobilePacket Data Service, depending on whichkind of communication one prefers.

Inmarsats Mobile Packet Data Service(MPDS) is a packet-switched service thatprovides packet-based charge rather thanairtime-based charge. It supports manypopular IP-based applications.

As for coverage in Polar Regions Inmarsat,as most other providers, are conservative inguaranteeing service. However, experimentshave shown that there has been GANcoverage a bit outside guaranteed areas,although not at the poles.



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I n m a r s a t G A N Products


S p e c i f i c a t i o n sThrane & Thrane TT-3080A(approx. USD 11 600 excluding VAT)

Weight: 1.7kg (terminal)3.5kg (antenna)

Dimensions H x W x D: 43 x 205 x 200 mm(excluding antenna)

Ambient temperature: -25C / +55CRelative humidity: 95% RH at 40C

Battery standby: 100 hoursBattery talk time: 4.8kbit/s: 4 hours64kbit/s: 2 hours

Battery data time: 4.8kbit/s: 2 hours64kbit/s: 35 min.

Power consumption: 0.1 W (idle)40 W (active)

Power supply: 9.5-20V DC

Port interface(s): 1xRJ45, 2xRJ11, 1xUSB,1xRS232, 1xaudio in,1xaudio out

Card interface(s): 1xSIM, 1xPCMCIAWireless interface(s) : Panel antenna

Thrane & ThraneTT-3080AThe TT-3080A from Thrane & Thrane is packedin a magnesium case, suitable for ruggedoutdoor use.

The antenna can be put 70 meters away fromthe terminal and it is easyto unfold and setup. Onecan double throughputto 128 kbit/s by linkingtwo terminals together,delivering large datatransfer and videotransmission at highspeed.

S p e c i f i c a t i o n sNera WorldCommunicator(approx. USD 10 600 excluding VAT)

Weight: 3.9 kgDimensions H x W x D: 68 x 260 x 355 mmAmbient temperature: -25C / +55CRelative humidity: 95% RH at 40C

Battery standby: 70 hoursBattery talk time: 4.8kbit/s: 9 hours

64kbit/s: 6 hoursBattery data time: 3 hoursPower consumption: 0.7 W (idle)

32 W (active)Power supply: 10-32V DC

Port interface(s): 1xRJ45, 1xUSB, 1xRS232Card interface(s): 1xSIMWireless interface(s): Panel antenna, DECT

NeraWorldCommunicatorThe WorldCommunicator from Nera ismade by polycarbonate, so the advancedelectronics are protected from extremeclimatic conditions.

One can double throughput to 128 kbit/s bylinking two terminals together, delivering largedata transfer and video transmission at highspeed.


I n m a r s a t B data

N e t w o r k Coverage: Global except poles

Global beam areaNr of satellites: 4 (Inmarsat I-3)Orbit height: 36 000 km


T e l e p h o n yVoice bit rate: 16 kbit/sServices: Point to point calling

Voice mailSMS

dataD a t aTransmission bit rate: 64 kbit/s (HSD)

(and 9.6 kbit/s)

Connection type: Circuit switchedDelay (up and down): 500 msDownload of 1 MByte: 2.2 min.Suitable for: Transfer of large les

Video conferencingVideo broadcastVideo store-and-forward

$E c o n o m i c sVoice: 2.8 - 3.8 USD/minData 9,6 kbit/s: 2.8 - 3.8 USD/minData 64 kbit/s: 9.5 - 10 USD/min

Prices are subject to change and varywith zones and time of day.

Inmarsat B is designed to replace theanalogous Inmarsat A. It offers better quality,

more cost-effective and greater capacity.The Inmarsat B system has channels for voice,telex, fax and data separately.

It offers an additional feature called Highspeed data (HSD), which is suitable for high volume data communication, suchas transfer of compressed and slow-scanvideo.

Two terminals can be connected to get atransmission rate of 128kbit/s. This is called

Duplex HSD.The coverage of Inmarsat B in Polar Regionsis better than the GAN service. Dependingon elevation and other factors, InmarsatB may be available on the outer parts ofAntarctica.

S u r v e y o f U s e r sSatisfaction:Desire:Clear communication compared toIridium on same ship

OKHigh



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I n m a r s a t B Products


S p e c i f i c a t i o n sNera Saturn Bm(approx. USD 22 000)

Power consumption: Recv: 100WSend: 200W

Power supply: 22-31V DCPort interface(s): 5xRJ11

2xRS232(9pin)1xRS232(25pin)1xNMEA0183

Wireless interface(s): Separate antenna unit

Terminal

Weight: 4kgDimensions H x W x D: 70 x 310 x 236mmAmbient temperature: -25C / +55CRelative humidity: 95% RH at 40C

Antenna unitWeight: 90kgDimensions H x W x D: 145 x 142(d)cmAmbient temperature: -35C / +55CRelative humidity: 95% RH at 40C

NeraSaturn BmThe Saturn Bm offers Inmarsat B service suchas telephone, telex, fax and data commu-nications. It provides digital b-directionalcommunication services.


dataD a t aFor short messages

Connection type: Packet switchedSuitable for: Remote tracking

Remote control

$E c o n o m i c sOther pricing plans than time and data

based plans apply for Inmarsat D+. Check with resellers.

Inmarsat D+ is a data service for shortmessaging and reporting using a built-in GPSreceiver. It is a low-cost, two-way store-and-forward solution offered by Inmarsat.

I n m a r s a t D+ data

P r o d u c t

N e t w o r k Coverage: Global except poles

Global beam areaNr of satellites: 4 (Inmarsat I-3)Orbit height: 36 000 km


The terminal can be used with web-basedtracking applications, remote monitoring and

asset tracking. It transfers GPS coordinatesand other environmental data.

S p e c i f i c a t i o n sSkywave DMR-200 L

Power consumption idle: 0.25WPower consumption active: Recv: 0.9W

Send: 10WWeight: 640 gDimensions L x Diameter: 100x160 mmAmbient temperature: -40C / +70CRelative humidity: 95% RH at 30CPower supply: 9-30V DCPort interface(s) : 1xConxall mini-con-xWireless interface(s ): Build-in antenna

Skywave

DMR-200 L The DMR-200 L is an integrated Inmarsat-D+ transceiver, GPS receiver and omni-directional antenna.

It is suited inlocations wherethe Inmarsatsatellites are ata low elevationangle to theterminal, for example Polar Regions.



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C o m p a n y b a c k g r o u n d

nmarsat was originally formed as anntergovernmental organization over 20

years ago. It focused on maritime-basedcommunication for voice, fax and data. In1999, Inmarsat became a privatized limitedcompany.

Until today, Inmarsat have launched no lesshan three generations of geostationaryatellites into the orbit, making it a worldwideeading company in global mobile satellitecommunication.

The rst generation, called Inmarsat I-2 satelliteswere launched during 1990-92, they provide

lease capacity as well as backup for the secondgeneration I-3 satellites.

The second-generation I-3 satellites werelaunched during 1996-98, which addsfunctionality that generates both global beamsand seven spot beams. The spot beams provideextra bandwidth for areas with higher demandof service. The current services (except RegionalBGAN) which Inmarsat offers today are usingthe I-3 satellites.

On 11 March 2005, the rst satellite of thenext generation I-4 satellites was launchedsuccessfully. See the Inmarsat BGAN section for more information.

I n m a r s a t

n m a r s a t r e f e r e n c e sClasatcom, http://www.clasatcom.com/inmarsat/inmarsathistory.htmnmarsat, http://www.inmarsat.com/

Marlink, http://www.marlink.com/Crystal communications, http://www.crystalcommunications.net/Skywave, http://www.skywave.com/Nera, http://www.nera.no/Trans European Technology, http://www.tet.co.uk/

G l o b a l s t a r data


N e t w o r k Coverage: RegionalNr of satellites: 48Orbit height: 1 500km

Low Earth OrbitOrbit time: 114 min.Inclination: 52Frequency: 1.6, 2.5 GHz (L, S-band)

T e l e p h o n yServices: Point to point calling

Call forwardingVoice mailSMS

dataD a t aTransmission bit rate: 9.6 kbit/sConnection type: Circuit switched

Delay (up and down): 16 msDownload of 1 MByte: 15 min.Suitable for: E-mail

Transfer of small lesSimple web browsingRemote controlling

$E c o n o m i c sOutgoing: 1 - 3 USD/minIncoming: 0 - 2.8 USD/minSMS: 0.50 USD

Prices are subject to change andvary with zones.

Globalstar was established in 1991 from adivision of Ford Aerospace. The 48 satelliteswere launched during 1997-2000 and thecommercial service began in late 1999.

Only after 2 year of operation, the companywent into Chapter 11 reorganization. In April2004, Thermo Capital Partners took over thecontrol of Globalstar.

In 2004, Globalstar announced to launch

new data compression service to increasethe data rate; it also announced that a newfaxing service would be available.



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G l o b a l s t a r Products


S p e c i f i c a t i o n sEricsson R290

Weight: 350gDimensions H x W x D: 162 x 62 x 39mmBattery (standby): 6 hoursBattery (talk time): 1.5 hoursPort interface(s): 1xAccesory portCard interface(s): 1xSIM

Wireless interface(s ): External antenna

S p e c i f i c a t i o n sQualcomm GSP 1620

Power consumption idle: 2.4WPower consumption active: Send: 4.8W

Recv: 0.5WWeight: 180 g

(excluding antenna)Dimensions H x W x D: 17 x 75 x 190mm

(exclude antenna)Ambient temperature: -30C / +60CPower supply: 5-16V DCPort interface(s): 1xDB25, 1xRS232Wireless interface(s ): External antenna

EricssonR290You can use EricssonR290 for both GSM andGlobalstar network. Whenhe cellular coverage is

not available, the phonecan switch to satellitemode and connect tohe Globalstar network.

t requires only one SIMcard, one phone andone phone number for both GSM and Globalstar network. You can getone bill to cover bothatellite and cellular callsf the service provider allows it.

QualcommGSP 1620 modemThe QUALCOMM GSP-1620 provides two ma-

jor features: two-way business-to-business In-ternet communication with eld equipmentand monitor, track, operate, manage andcontrol their remote assets.

G l o b a l s t a r r e f e r e n c e sGMPCS, http://www.gmpcs-us.com/products/globalstar/globalstar.htmGlobalcom, http://www.globalcomsatphone.com/globalstar/history.htmlCellular, http://www.cellular.co.za/phones/ericsson/archive/ericsson_r290.htmQualcomm, http://www.qualcomm.com/qws/solutions/gsp1620.html


N e t w o r k Coverage: Global

(Only store-and-forward)Nr of satellites: 30Orbit height: 800 km

Low Earth OrbitOrbit time: 101 min.Inclination: 45 (two: 78 and 108)Frequency: 137 - 150 MHz

dataD a t aDownlink bit rate: 4.8 kbit/sUplink bitrate: 2.4 kbit/sConnection type: Packet switchedDelay (up and down): approx. 10 msDownload of 1 MByte: 30 min.Suitable for: Email

Transfer of small lesRemote controlling

$E c o n o m i c sSubscription fee 45 USD/monthTrafc fee approx. 5 USD/kbyte

Prices are subject to change.

Orbcomm was the rst service provider ofglobal LEO satellite data and messaging

communication service.It provides narrowband two-way digitalmessaging, short data communication andGPS service globally.

Orbcomm has true global coverage,but there are only two satellites that orbit

O r b c o m m data

over Polar Regions, therefore the datatransmission delay could be signicantlyhigher than transmitting from lower altitude,regions.

Orbcomm announced that they would

launch a new satellite in Q1 2006. Thesatellite will be put into a Polar orbit asOrbcomms third polar orbiting satellite. It willstill provide the existing services plus supportfor United States Coast Guards AutomaticIdentication System (AIS) capability.



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S p e c i f i c a t i o n sStellar-sat ST2500

Power consumption idle: 0.72WPower consumption active: Send: 30W

Recv: 1.08WDimensions H x W x D: 35 x 110 x 222mmAmbient temperature: -40C / +85CPower supply: 9-36V DCPort interface(s): 3xRS232

6xdigital in6xdigital out5xanalog in


Stellar-satST2500The Stellar-sat ST2500 modem has manyerial and I/O interfaces for the connection

of many sensors.

The power management features and GPSaccuracy are one of the best in the market.

S p e c i f i c a t i o n sPower consumption: 1.44 W (idle)Power consumption: 30 W (active)Weight: 425gDimensions H x W x D: 25 x 124 x 213 mmAmbient temperature: -40C / +85CPower supply: 9-36V DCPort interface(s): 2xRS232

1xRS485,4xdigital out switches,8xdigital in4xanalog in


QuakeGlobal Q2000Quake Global Q2000 module has fullRF/EMI protection and shielding to ensureenhanced RF performance and systemsensitivity.

Reliable operation in remote and severeenvironments is ensured by an extendedoperating temperature range and avibration-resistant design ensures

O r b c o m m Products


O r b c o m m r e f e r e n c e sMobilecomms-technology, http://www.mobilecomms-technology.com/projects/orbcomm/Orbcomm, http://www.orbcomm.com/Stellar Satellite Communications, http://www.stellar-sat.com/html/products/st2500.htmlQuake Glocbal, http://www.quakeglobal.com/prod_data_sheets/q2000.pdf

I n t e l s a t V S A T data


N e t w o r k Coverage: Global except polesNr of satellites: 27Orbit height: Geostationary Earth OrbitOrbit time: 24 hoursInclination: 0 (usually)Frequency: Several possibilities

dataD a t aTransmission bit rate: 64 kbit/s - 45 Mbit/sConnection type: Circuit switchedDelay (up and down): 500 msSuitable for: All services types including

broadband services

$E c o n o m i c sExample oneDownlink bit rate: 128 kbit/sUplink bit rate: 64 kbit/sMonthly fee: 4 700 USDInitial setup cost: 1 500 USD

Example twoDownlink bit rate: 256 kbit/sUplink bit rate: 128 kbit/sMonthly fee: 6 900 USDInitial setup cost: 1 500 USD

The monthly fee enables unlimited usage.Prices are subject to change.

VSAT stands for Very Simple ApertureTerminal. It is a solution for xed mountedtwo-way satellite communication.

Intelsat provides VSAT Internet Connection

services to a Tier-1 Internet backbonenetwork through its Internet Trunking Service(ITS). It bundles the space segment, teleport,and Internet services into a completesolution for customers with a single monthlytariff.

The satellites are GEOs with coverage toapprox. 75 degrees north and south.

Data rates from 128 kbit/s to 45 Mbit/sdownlink can be provided depending onprotocol, equipment and monthly cost. Therecommended frequency for Polar Regionsis C-Band with an antenna of 2.4 meters indiameter.

Other teleports could be used, such asthe Stockholm Teleport. Intelsat is the VSATprovider with the biggest global coverage.There are many other, such as Eutelsat, withvarious coverage.

V S A T r e f e r e n c e sStockholm Teleport, http://www.ssc.se/default.asp?groupid=20049101584724Intelsat, http://www.intelsat.com



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D V B - R C S dataDigital Video BroadcastingReturn Channel via SatelliteN e t w o r k Frequency downlink: 14 GHz (Ku-band)Frequency uplink: 30 GHz (Ka-band)

There are at this moment no knownsatellites with coverage in Polar regionsthat offer DVB-RCS services.

dataD a t aDownlink DVB-S bit rate: 35 - 40 Mbit/sUplink RCS bit rate: 144 kbit/s - 2 Mbit/sConnection type: Packet switchedDelay (up and down): 500 msSuitable for: All types of services

including broadband services

$E c o n o m i c sDVB-RCS services cost less than VSATservices since the capacity is sharedwith others. Prices differ between serviceproviders.

Equipment costs from 1 300 USD to 64 000USD depending on transmit capability ofthe terminal.

Expertise is needed for the network sustainability and network maintenance.

Digital Video Broadband Return Channelvia Satellite is a two way DVB satellite systemwhere the end user has the transmit capabilityvia the same antenna. In conventional digitalvideo satellite broadcasting, the user terminalequipment only receives.

The satellite user terminal receives the DVB-Sransmission in the standard way generatedby a satellite hub station. Packet data is sentover the forward link in the common way for e.g. MPEG, data streaming. A common satellitechannel has 36 MHz bandwidth and data ratesup to 35-40 Mbps.

The satellite user terminal transmits by using aMulti Frequency Time Division Multiple AccessMF- TDMA) access scheme to share the

capacity available for transmission by theerminal. The band used to transmit from terminalo hub stations is Ka band(29.5-30 GHz).

D V B - R C S r e f e r e n c e sDr Gorry Fairhurst, http://erg.abdn.ac.uk/research/future-net/digital-video/DD Electronics, http://www.ddelec.com/internet/two_way.htmGilat Satellite Networks, http://www.gilat.com/SkyEdge_DVB-RCS_TechnicalSpecs.asp?Sbj=635

D i s h s i z eThe transmission speed depends on thesize of the satellite dish.

Dish s ize Sending speed65-75 cm 144kbps75-90 cm 384kbps95-130cm 2048kbps


A r g o s data

N e t w o r k Coverage: True globalNr of satellites: 6 (NOAA)Orbit height: 833 km

Low Earth OrbitOrbit time: 101 min.Inclination: 98.8Frequency: 400 MHz

dataD a t aNo downlink Uplink bit rate: max 2560 bit/sConnection type: Packet switched

Suitable for: Remote tracking

$E c o n o m i c sThere are two types of prices:

1) The World Meteorological Organization and IntergovernmentalOceanographic Commission organizes the Joint Tariff Agreement. The JTAnegotiates a tariff structure each year and that is available for all government-nanced or non-prot programs.

2) Additional services(not connected to JTA and will be billed directly from Argos, 2004 prices)Automatic Distribution Service (ADS) usingemail or FTP through the Internet

0.10USD/kbyte

Accessing data on-line using Telnet/SSHthrough the Internet

0.25USD/min

Databank for data archived monthly, postedas mail

180USD/CD-ROM (600Mb)180USD/3.5 diskette (1.4Mb)

The Argos system has been operational since1978. It was founded under an agreement(Memorandum of Understanding) between

the National Oceanic and AtmosphericAdministration (NOAA, USA), the NationalAeronautics and Space Administration(NASA, USA) and the French Space Agency(CNES).

Argos service includes locating platformequipped with a transmitter anywhere inthe world, collecting data from sensorsconnected to the transmitter . Over 10

thousand Argos transmitters are nowoperating around the world.

The satellites get the data sending from thetransmitter and retransmit it to the Argoscenter for processing. One can retrieve thedata through public data networks, oftenwithin 20 minutes of transmission.

Argos system uses small transmitters with lowpower consumption, it means that Argoscan be used to track small animals.



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A r g o s Product


PTT-100 30gSolar Argos/GPSPTT-100 30g Solar Argos/GPS provide ac-curate location information and perfectdata collection for researchers and it onlyweight for 30g. It means it can be carriedon polar bears, sh and birds easily. Another advantage of PTT-100 Solar Argos/GPS ishe efcient power management.

t gains the power from a tiny solar panel,with the latest battery managementechnology, the solar power can support it

for a quite long time. It can be programmedto record GPS locations at intervals duringthe day and relay them to the user via Argosevery third day.

S p e c i f i c a t i o n sPTT-100 30g Solar Argos/GPS

Dimensions: 62 x 22 x 21 mmWeight: 30 gPower output: 200mWOutput impedance: 50 ohmsTransmission interval: 45 to 120 sSupply voltage: 3.6 - 4 VTemperature range: -15 to 45 C

A r g o s r e f e r e n c e sArgos, http://www.argosinc.com/Microwave Telemetry, Inc., http://www.microwavetelemetry.com/Bird_PTTs/12g.php

F u t u r e s a t e l l i t e s


T e l e d e s i cFrom the beginning, Teledesic planned 840active satellites in 1994, the number drops to288 active satellites in 1997 after a Boeing-led redesign and before the merge withMotorolas Celestri.

Teledesic later overtook ICO. In February2002, Teledesic announced that thirty MEOsatellites are planned. On 1 October 2002,Teledesic was ofcially suspending its satelliteconstruction work.

E l l i p s o Elliptical is unique for its design of ellipticalMedium Earth Orbits (MEOs) where thealtitude varies depending on the coordinatesof the satellites.

It utilizes the property that the Worldspopulation is concentrated on the North halfof the Earth, thus it has more coverage inthe North than the South, makes bandwidthsharing more effective.

S k y b r i d g eSkyBridge was proposed by Alcatel andit was a 64-satellite LEO constellationconcept. Now they are plans to changeto a geostationary satellite system, while inJanuary 2002 it was reported that SkyBridgewas on hold.

I C OICO (for Intermediate Circular Orbit) wasoriginally designed by Inmarsat, knownas Inmarsat P. It later formed a separatecompany and then led for bankruptcy [4].Craig McCaw led a group of internationalinvestors to provide $1.2 billion to acquirethe ICO business in May 2000.

The concept of ICO is to make personalmobile communications possible all over the World by planning a family of qualityvoice, wireless Internet and other packet-data services. The goal of ICO is for datacapabilities and voice quality It will becomparable or superior to those of currentterrestrial mobile networks.

dataD a t a Planned transmission bitrates

System Teledesic Ellipso Skybridge ICO

Downlink 64 Mbit/s 28.8 kbit/s 5/60 Mbit/s 144 kbit/sUplink 2 Mbit/s 28.8 kbit/s 0.5/6 Mbit/s 144 kbit/s

R e f e r e n c e sLloyds satellte constellations, http://www.ee.surrey.ac.uk/Personal/L.Wood/constellations/Ellipso, http://www.ellipso.com/ICO, http://www.ico.com/

data



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G P S Global Positioning SystemN e t w o r k Coverage: Truly globalNr of satellites: 24 (plus spares)Orbit height: 20 200 km

Medium Earth OrbitOrbit time: 12 hoursInclination: 55Frequency: 1.58 GHz (L-band)

$E c o n o m i c sThe standard GPS service is free of directuser fees.

The Global Positioning System, usually calledGPS (the US military refers to it as NAVSTARGPS), is a satellite navigation system usedfor positioning ones precise location andproviding a highly accurate time referencealmost anywhere on Earth or in Earth orbit.

It uses an intermediate circular orbit (ICO)satellite constellation of at least 24 satellites.The GPS system was designed by and iscontrolled by the United States Departmentof Defense and can be used by anyone,free of charge.

The GPS satellites continuously transmitdigital radio signals that contain data onthe satellites location and the exact timeto the earth-bound receivers. The satellitesare equipped with atomic clocks that areprecise to within a billionth of a second.

The GPS system was developed for militaryservices at beginning and it has beenpopular to civilians now. The GPSs StandardPositioning Service worldwide is free ofcharge. Only a low cost GPS receiver (price$100 to $200) is needed, which could becombined in a bundle with a PDA or cellphone.

In Europe, companies concern aboutthe level of control over the GPS network and commercial issues has resulted in theplanned GALILEO positioning system. Galileowill be a political statement of Europeantechnological independence from theUnited States.

A strong motivator for seeking technologicalindependence is the policy of the UnitedStates government to employ only Americancompanies for the building of componentsfor the GPS.

GPS is also used widely in navigation. It helpspeople know how to get another placeduring expedition and traveling.If expedition is the process of researchingsomething from one location to another,then tracking is the process of monitoringit as it moves along. GPS tracking service isalso suitable to the animal investigation.

There are some other commercial uses ofGPS, including land measurement, mappingand road construction.

R e f e r e n c e sGalileo, http://www.galileoju.com/indexf.htmGPSWorld, http://www.gpsworld.com/gpsworld/

L i n k Range: IntercontinentalFrequency: 2 - 15 MHz

V o i c eHalf duplex - Walkie talkie typecommunication with varying quality

H F Radio High Frequency data

dataD a t aDownlink bit rate: 0 ~ 2 kbit/s*Uplink bit rate: 0 ~ 2 kbit/s*Delay (up and down): varying*Download of 1 MByte: ~70 min. or more*

Suitable for: E-mailTelex

Transfer of small les*Depending on distance, time of day, and several

other factors

$E c o n o m i c sYearly frequency licensing fees should bepaid to the involved countries. Such feesare very cheap compared to all satelliteservices.

HF radio links is useful for half-duplex voicecommunication, but unreliable. The reliabilitydepends on the weather conditions,antenna, frequency, right angle of takeoff, output power, etc. While we are usingfor voice communication we can either transmit (push to talk) or receive, but not theboth at the same time.

It does not support for voice conferenceand it should be online always. However, it iseconomically feasible when compared withsatellite phones, microwave and wirelesslinks. It does not require any expensivehardware. It does not require much technicalknowledge. It is easy to handle and use.

When compared with wireless technologylike 802.11x, which can cover at the maxof 10 miles. This help for long distancecoverage. The HF radio signals, by reectingto ionosphere follow the curvature of theearth. Therefore, we can reach quite longdistance by using the HF signals.

E-mail through HF links is also possible, butnot browsing. Once radio link connect tothe remote HF link it downloads mail andsend the mails to any mail. It allows sendingthe attachment of 110Kbytes of plain text.It also allows sending fax through E-mail.There is software available for sending mailthrough HF-links like Bush-mail, Wave-mailand Air-mail etc.


Slow but OK

OKMedium





15/23

H F R a d i o Products


Bush mailBush-mail is an E-mail system. It is providingervices in Africa to connect the remote villages

where is no telephone system.

Services provided by Bush-mail:Once the Bushlink is connected we can

automatically upload and download thencoming mails. It allows 5 pages of plain text110kbytes) or attachments of word of 110kbytes

or excel sheet of 110 Kbytes at the maximumper mail for commercial usage.

It also provides the service of sending faxhrough e-mail.It doesnt allow spam and junk mails.It requires minimum power of 12V.Time delay of sending and receiving the mail

rom the bush link to anywhere in the world isapproximately 30 minutes. However, this canalso be improved by using proper frequency to5mintues for forwarding.

In the futureThe Kielradio company is planning to expandhere HF data network services in Antarctica.

There future plans to set station in Patagoniaand South Africa, so from there they can cover he Antarctica region. There services in thisegion may be available by October 2005.

Wave mailWave mail is e-mail system used in radio links.All the e-mails sent through this are compressedautomatically while sending and decompressionis done after receiving. It can be also used tosend e-mails through satellite phones (Iridium,Inmarsat, and Thuraya) attached to thismodems.

Services: We can send and receive E-mails with text,graphics. Compression and decompression is doneautomatically Transceiver control Message deliver and failure notication is alsosent, its optional One wave mail station can handle 7modems Wave mail allows online discussion betweentwo stations

HF modemSchuemperlin Pactor-III is software upgrade ofPactor-II modem. It improves 3 to 5 times faster then Pactor -II. When compared with Pactor-II,Pactor-III uses most robust modulation. Under good conditions, the propagation is equivalentto satellite phones.

The maximum speed of uncompressed is 2722bit/s and the online compression can be up to

5.2kbps. The Pactor-III is multi-tone waveformuses up to 18 carriers, but Pactor II uses twocarriers. A HF modem is approximately 680USD.

H F R a d i o R e f e r e n c e sBushlink, http://www.bushlink.co.tz/index.htmKielradio GmbH, http://kielradio.com/Schuemperlin, http://www.schuemperlin.com/

L i n k Range: Less than or equal to line-of-

sight depending on transmittingpower among other things

Frequency: 30 - 300 MHz

V o i c eHalf-duplex - Walkie-talkie typecommunication with varying quality

V H F Radio Very High Frequency

$

E c o n o m i c sThere are license free frequency spectrumsof the VHF band in many countries.

Transceiver: 100-300 USD

Repeater: 700-1500 USDAntenna: 30-300 USD

Very high frequency (VHF) is the radiofrequency range from 30 MHz (wavelength10 m) to 300 MHz (wavelength 1 m).Frequencies immediately below VHF is HF,and the next higher frequencies are knownas Ultra high frequency (UHF).

Common uses for VHF are FM radio broadcastat 88-108 MHz and television broadcast(together with UHF). VHF is also commonlyused for terrestrial navigation systems andaircraft communications.

VHF frequencies propagation characteristicsare ideal for short-distance terrestrialcommunication, with a range generallysomewhat farther than line-of-sight fromthe transmitter. Unlike high frequencies (HF),

the ionosphere does not usually reect VHFradio and thus transmissions are restricted tothe local area.

VHF is also less affected by atmospheric noiseand interference from electrical equipmentthan low frequencies. Whilst it is more easilyblocked by land features than HF and lower frequencies, it is less bothered by buildingsand other less substantial objects than higher frequencies.

An approximation to calculate the line-of-sight horizon distance is: Distance in miles= square root of (1.5 * height of antenna infeet)


Good short rangeDependability too variable

OKHigh


V H F R a d i o R e f e r e n c e sTackletogo.com, http://store.tackletogo.com/sthohxhavhf1.htmlMultec Communications,http://www.rfwiz.com/Maxon/Repeaters/Maxon_SR-6151_SR-6451_Repeater.htm



16/23

V H F Radio Products


S p e c i f i c a t i o n sStandard Horizon HX260S Handheld VHF

Weight: 0.45 kgDimensions: 135 x 61 x 41 mmTemperature Range: -20 C to +60 C

Battery Voltage: 7.2 VDCStandby: 30mAReceive: 180mATransmit: 1.5A High, 0.7A LowBattery Life: 8 hours 5W, 12 hours 1W

(5% TX, 5% RX, 90% Standby)

Frequency: TX: 156.025-157.425 MHzRX: 156.050-163.275 MHz

S p e c i f i c a t i o n sMaxon SR-6100 seriesRepeater & Base Station

Weight: 7.2kgDimensions: 184 x 216 x 298 mmTemperature Range: -30 C to 50 CFrequency Range: VHF 148-174 MHz

UHF 450-480 MHzInput Voltage: 13.8 VDC 20%Standby:


17/23

W - M A N IEEE 802.16 WiMAX data


WiMAX is an acronym that stands for Worldwide Interoperability for MicrowaveAccess, is a certication mark for productsthat pass conformity and interoperabilitytests for the IEEE 802.16 standards. IEEE802.16 is working group number 16 of IEEE802, specializing in point-to-multipointbroadband wireless access.

WiMAX is an evolution technology usedto improve the last mile broadbandconnectivity in the metropolitan area. It canprovide long distance and exible coverageand much higher data rate services than thetraditional last mile solutions, like DSL/LAN.

The current 802.16 standard is IEEE Std 802.16-2004, approved in June 2004. It rendersthe previous (and 1st) version 802.16-2001obsolete, along with its amendments 802.16aand 802.16c. IEEE Std 802.16-2004 addressesonly xed systems. This standard may bereferred to as xed wireless because it usesa mounted antenna at the subscribers site.

The antenna is mounted to the user site in thebalcony or a roof, which communicate to thebase station without cables. This technologycan provide various data rate solutionbased on the customers requirement andthe coverage of the central base station. Inanother word, its an ideal solution for both

remote area and crowded urban area. Seegure-1

Intel began shipping its rst-ever processor that taps into the wireless standard 802.16-2004 in April 2005. In addition, someequipment vendors announced productsusing the chip, formally called the Intel Pro/Wireless 5116.

An amendment 802.16e is in the works whichadds mobility components to the standard.802.16e standard focus on full portabilitysolution. The mobile clients could moveanywhere with the connectivity with theWiMAX base station without xed antenna aslong as under its coverage. See gure-2. The802.16e is still in draft state. This amendmentis expected to be completed in 2006.

Intel, the world leading Microprocessor Company, is the maker of WiMAX andhas rolled out the silicon for WiMAX. TheWiMAX Forum is an industry-led, non-prot corporation formed to promote andcertify compatibility and interoperabilityof broadband wireless products. Member companies support the industry-wideacceptance of the IEEE 802.16 and wirelessMAN standards, including Alcatel, AT&A,Cisco System, Ericsson, Nokia, SiemensMobile, etc.

L i n k (theoretical)Standard Range Frequency

802.16 2004 Up to 45 km 2 - 11 GHz802.16 e 5 Km 2 - 6 GHzdata

D a t a (theoretical)Standard Throughput Download

of 1 MByte802.16 2004 Up to 75 Mbit/s 0.1 s802.16 e Up to 30 Mbit/s 0.3 s

Suitable for: Interconnecting WLANs

W - M A N R e f e r e n c e sIEEE 802.16 Working Group on Broadband Wireless Access Standards,http://grouper.ieee.org/groups/802/16/WiMAX Forum , http://www.wimaxforum.org/homeIntel, http://www.intel.com/netcomms/technologies/wimax/

L i n k Coverage: Up to 35 km

(one macro cell)

Frequency: 900 MHz1800 MHz1900 MHz

V o i c eVoice bit rate: 13 kbit/sServices: Point to point calling

Conference callingCall forwardingCall holdCaller IDVoice mailShort Message Service (SMS)

G S M Global System for Mobile Communication data

dataD a t a

Dataservice

Bitrate Downloadof 1 MByte

Switching

Standard 9.6 kbit/s 15 min Circuit switchedHSCSD Up to 60 kbit/s 2.5 min Circuit switchedGPRS Up to 40-50 kbit/s 3 min Packet switched

Suitable for: E-mailTransfer of small to medium lesWeb browsingRemote controlling

Generally, the coverage is based on thenumber of subscribers. We could set up amacro cell in the remote area; if number ofsubscribers increases, micro cell could be setup in the macro cell hierarchically as long asfollowing the frequency reuse concept.

Typically, one cell could provide a maximumof 1000 channels for calling simultaneously.It means 1000 subscribers could call at thesame time.

Ericsson is the largest supplier of mobilesystems in the world and supports all major standards for wireless communication.Ericsson can provide mobile communication

equipments of all mainstream 2G and 3Gstandards around the world.

For the polar expeditions, Ericsson plays animportant role of GSM system sponsor. Awhole GSM system was set up on one of thevessels and a volunteer from Ericsson joinedthe expedition to maintain and operate theGSM system.

With one base station set on one of thevessels, the whole expedition teams werecovered and people on different ships couldeasily maintain contact with very goodvoice quality instead of VHF radio or satellitephones.

$E c o n o m i c sGSM is a complex and expensive system,which costs approximately 3 million USDfor the system (without installation) andaround 0.5 million USD a year for opera-tions and maintenance.

S u r v e y o f U s e r sSatisfaction:

Desire:High

High





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19/23


I n t e r c o n t i n e n t a l d a t a

Trafc costThe satellite technology services that maybe relevant for polar expeditions differ insome aspects such as transmission speed,delay, reliability and pricing.

Since expeditions differ a lot in length,destination and number of participants,they have very different needs for communication.

No service with time-based pricing is efcientfor sporadic usage such as web browsing.For such uses, the packet-based servicessuch as Inmarsat GAN MPDS and the newBGAN would be suitable, but also xedpriced VSAT could be suitable if the monthlytrafc is more than 300 MByte per month.

The graph below shows, for each ofthe intercontinental communicationstechnologies, the monthly cost of datatrafc as a function of the amount of datasent each month.

It is assumed in the calculations thattransmissions over services with time-basedpricing are done as efciently as possible;that there is almost no idle time. That impliesfor example sending of les and batches ofemails, not web browsing.

For such transmission of les and emails ofan amount of no more than ten MByte per month, HF Radio and Inmarsat B are thecheapest.

Sending or receiving from 10 to 300 MByteper month makes Inmarsat GAN ISDN andHF Radio the cheapest. HF Radio, being far the cheapest, however has poor reliabilityand very low speed. If time is a factor, itsnot an option.

For any type of usage with amounts ofover approximately 300 MByte, Intels VSATalternative 1 is the cheapest. If higher speedis desired, there are substantially faster alternatives at correspondingly higher costs.

1

10

100

1 000

10 000

100 000

1 000 000

0 , 2 5 0 ,

5 1 2 4 8 1 6 3 2 6 4 1 2 8

2 5 6

5 1 2

1 0 2

4

2 0 4

8

4 0 9

6

8 1 9

2

1 6 3 8 4

3 2 7 6 8

G l o b a

l s t a r

Intelsat VSAT alt 2

HF Radio

I r i d i u m

I r i d i u m

x 8

O r b c o m

m

Intelsat VSAT alt 1

I n m a r s

a t B

I n m a r s

a t G A N

I S D N

I n m a r s

a t G A N

M P D S

M o n

t h l y c o s t

( U S D )

Monthly amount of data sent (MByte)

C o m p a r i s o n


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I n t e r c o n t i n e n t a l d a t a Continued

Transmission speedn the graph below, the differences ofransmission speed between intercontinentalcommunication technologies is shown.

The fastest one is VSAT, which can provideup to 45 MBit/s. Inmarsats coming serviceBroadband Global Area Network will be theastest available with a mobile terminal. For

handheld equipment Globalstar is currently theastest with its 9.6 kbit/s.

HF Radio, which is the slowest and mostunreliable, is often also the cheapest. It canserve as a backup as it can be independent ofservice providers.

In some parts of Polar Regions, choosing is notreally possible due to the coverage situation. Atthose places, such as the poles, Iridium is the onlychoice for reliable real time communication.

HF radio could work, but is interfered with bynorthern lights. Orbcomm could be used for store-and-forward of small messages.

H F R a

d i o

I r i d i u m

O r b c o m m

G l o b a

l s t a r

I r i d i u m

x 8

I n m a r s a

t

G A N M P D S

I n m a r s a

t

G A N I S D N

I n m a r s a

t B

I n t e l s a

t

V S A T a

l t 1

I n t e l s a

t

V S A T a

l t 2

I n m a r s a

t

B G A N

0

400

300

200

100

kbit/s


R e g i o n a l d a t a

Speed and rangeShowing in the graph below is the maximumtransfer rates and distances for regional andlocal connectivity technologies that could beused within an area on Polar expeditions.

Sorted by distance, W-LAN on the left is the onewith the shortest distance offered. HF Radio issuperior with its intercontinental range. The barsin the back indicate these distances.

The bars in the front illustrate data speed. Ascan be seen, 802.16 2004 WiMax is superior for distances up to 45 km.

It should not be forgotten that all thesetechnologies use different types of equipment,everything from a GSM phone to large antennamasts.

Cost is another issue that differs a lot betweenthem. See the technology section for moreinformation.

WLANGSM

WMAN

Microwavelink HF Data

Mbit/s

km0

10

20

30

40

50

60

70

80

90

100

5000+

8 0 2

. 1 1 g

8 0 2

. 1 6 2 0 0 4

L o c a l v o i c e c o m m u n i c a t i o n

For voice communication a few alternativesare suitable. Handheld VHF is a classic, notneeding any infrastructure. Problems are thatline-of-sights is need and that the sound qualityoften is poor. It is a half duplex technologywhich means that only one can speak at thesame time. This can be frustrating for people noused to that.

GSM is a alternative. It provides a more reliable

and more usable way of communicating.It could be hooked up to the internationalphone network over satellite, enabling globalconnectivity. Cost is however very high. Seetechnology section.

Another reliable and good alternative is satellitephone such as Iridium or Globalstar. While theyoffer great communication and security, theyore often a bit to expensive for small talk.

C o m p a r i s o n


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R e s e a r c h s t a t i o n sLet us take a possible scenario with tworesearch stations situated 40 km apartrelatively close to the fringe of Antarctica.One of them is the main station with room for 20 persons. The other is a small station wereve persons can spend a couple of nights.There are also mobile units, i.e. snowmobilesaround and between the stations.

These parties need communication betweeneach other and to the civilization back home. Most important is voice for safetypurposes but also data may be needed for sending research data, coordinates andphotos.

IntercontinentalFor global connectivity, several technologiescould be suitable. VSAT might be a bit topricey for this scenario. Assuming that thereis coverage on the Inmarsat I-3 global beam,Inmarsat B will be the cheapest availablesatellite service for transmission of les andemails.

HF radio could be a very good complementfor transmission of not so urgent emails.Since there are no trafc costs, one couldtry to send a batch of emails with HF rst. Ifunsuccessful, due to southern lights (aurora)or other interference, one could just switchon the Inmarsat B.

Iridium is a good backup, providing a reliableway to send emails and make importantphone calls. There should be at least onephone per location and mobile unit.

For web browsing, a packet-based serviceis optimal. The closest to that currently inAntarctica would be the Iridium InternetDirect Data service, which simulates packetswitching. However, at a speed of 2.4kbit/s web browsing is hardly a pleasantexperience, even without loading ofpictures.

In the near future however, Iridium say theywill provide a real packet-based serviceof 9.6 kbit/s. This would enable a morecost efcient way for simple browsing. Textchatting could be the absolutely cheapest

S o l u t i o n s

A research station in AntarcticaPhotograph by: Jenny Baeseman/Univ. of Colorado - National Science Foundation


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C o m p a r i s o n & S o l u t i o n s r e f e r e n c e sCONTACT product, http://www.humanedgetech.com/IDG Europe AB, http://www.idgeurope.com/Telemar Scandinavia, http://www.telemar.se/Iridium, http://www.iridium.com/Inmarsat, http://www.inmarsat.com/home.aspxEricsson Response, http://www.ericsson.com/about/ericssonresponse/

I c e b r e a k e r This scenario is on an icebreaker, housingmore than a hundred people for a coupleof months. Continuing on the solutions for the research stations, here would be naturalto have several WLAN access points, linkingall the passengers with local email and lesharing. If there are several ships, they couldbe linked with WLAN and WMAN.

VoIP could be a way for local voicecommunication. An even more appealingsolution is to have a GSM system onboard,enabling everybody to use their own cellular phones to call each other without trafccosts. Such a system is however costly and

requires a person to maintain it.

The Ericsson Response program did preciselythat on the ACEX expedition 2004. With theresults were successful, they decided todo it again on Beringia 2005. They are alsogoing to connect the GSM system to theicebreakers internal telephone system.

For intercontinental communication, a VSATor DVB-RCS solution could be feasible. For that, a stabilized antenna is needed. Suchan antenna is a dish that automaticallyrotates to always point to the satellite for any bearing of the ship.


R e s e a r c h s t a t i o n s Continuedway of communication with the civilizationback home.

Although Inmarsat doesnt guaranteeanything, their new BGAN service may havecoverage also. This would most likely bemore cost efcient and pleasant than anyIridium service.

With all that bandwidth, one needs to restrainoneselves and others usage. The cost canquickly escalate to repulsive levels if youare not careful. Chatting on MSN, ICQ or IRC is very cheap, but if your Windows startsdownloading updates in the background,you could be spending 100 USD per minutewithout knowing it.

For voice, Iridium would be the cheapest.Inmarsat B could be used for backup or when there is need for higher sound quality.Voice over IP (VoIP) over BGAN would bepossible but not economically feasible.

RegionalBy having a WLAN access point at the mainstation, exible transmission of les and emailis possible between researchers laptops. Alocal email server could be set up providing

an easy and familiar way to share results,photos, thoughts and les within the station.

To make it more valuable, WLANs could beset up on the other station and on mobileunits. These could be interconnectedwith as a WMAN (Wireless MetropolitanArea Network) such as WiMax, when itsavailable.

In this case, VoIP would be an excellent wayfor voice communication, replacing VHFradios. PDAs with built-in WLAN capabilitiescould be used.

For safety purposes, automatic trackingof mobile units could be done with acombination of GPS and an Iridium modemthat sends coordinates regularly with theShort Burst Data service. The informationcan then be accessed at the main stationthrough an internet connection.

One good way to easily put text, photo,audio and even video on a personal homepage is to connect a PDA or laptop toan Iridium phone. CONTACT is a productincluding software and server space thatmakes it very easy and cost efcient toupdate a home page from anywhere in theworld.

S o l u t i o n s

A mobile unit in AntarcticaPhotograph by: Kris Kuenning - National Science Foundation

An icebreaker Photograph by: Al Hickey - National Science Foundation


23/23

Documents

Polar Communications Handbook