none IT concepts geostationary mediumEarth and lowEarth orbit satellite characteristics spectrum and licensing satellite technology progress important Internetservice satellite projects and some of their implications ID: 709028
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Slide1
Satellite connectivity
Skills
: noneIT concepts: geostationary, medium-Earth, and low-Earth orbit satellite characteristics, spectrum and licensing, satellite technology progress, important Internet-service satellite projects and some of their implications
This work is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 License. Slide2
Where does this topic fit?
Internet conceptsApplicationsTechnology (communication)ImplicationsInternet skillsApplication development
Content creation (images)Slide3
Altitude (miles)
Latency
(milliseconds)Orbit time (hours) Low-earth orbit (LEO)< 1,200 20-25Around 2 Medium Earth orbit (MEO)1,200-22,236110-130
Around 12
Geostationary orbit (
GEO
)22,236250-28024
Orbit characteristics calculator
Where would the moon be in this illustration?
Why
is the GEO altitude exactly 22,236 miles while LEO and MEO are ranges?
Satellite orbit characteristicsSlide4
GEO: The vision
In 1945, Arthur C. Clarke proposed geostationary satellite
communication in an article entitled “Extra Terrestrial Relays.”He later wrote 2001 a Space Odyssey and other science fiction stories.Fig 2. Transmission from A being relayed to point B and area C; transmission from D being relayed to whole hemisphere.Slide5
Animate
GEODone for many years.
Used primarily for broadcast and slow, expensive rural Internet connectivityOrbits in 24 hours, so remains fixed in the skySlide6
Source
GEO
GEO ISPs and broadcast companies are well established.GEO technology has and continues to improve.Since the satellite appears to be stationary, the antenna does not have to move.Replace with a photo of a sat antennaSlide7
Animate
GEO
SourceSlide8
MEO
US GPS geolocation services uses x sats at xx altitude.
Between x and y are visible at once.China, Russia and the European Community also operate MEO geolocation systems.Animate
SourceSlide9
O3b status
MEO - SES O3b
Leading MEO Internet service provider todaySatellites orbit at the equatorServing maritime, airlines, governments and rural mobile operatorsWill deploy significantly advanced “Mpower” satellites in the next two yearsSlide10
MEO & GEO
Animated sourceO3b’s MEO satellites will interoperate with over 50 GEO satellites of their parent company SES.Slide11
LEO
Traditionally used for Earth imaging, and scienceLarge constellations for global Internet service being developed
AnimateTeledesic constellation
Teledesic
failed in the 1990s, what has changed since then to make newcomers optimistic?Slide12
LEO constellations hope to provide Internet connectivity for
Homes and organizations in poor and remote areas Ships at sea and other off-shore locations like oil rigs.Airplanes in flightCellular networks and WiFi hotspots
Government agencies and large enterprisesInter-city and international backbone providersSlide13
Live map
Moving “footprint” of a famous LEO satelliteThe International Space Station is in low-Earth orbit below the altitudes of the planned Internet-service constellationsSlide14
O3b status
OneWeb
statusSpaceX Starlink statusLeading LEO/MEO new-comersTelesatAmazonChinaSlide15
What will happen if the flashlight (satellite) moves farther away?
Where is the light the brightest?
Satellite footprintSlide16
Footprint example – LEO and VLEO (very low Earth orbit)
Where would the strongest signal would be within the footprint?Slide17
Some evolving, critical technologiesElectronic
beam switching and shapingInter-satellite laser linksComponent reuseDebris mitigationLayer integrationCurrent event on mr steven catching a fairingSlide18
No moving parts
fast switchingMass productionWill improveAnimated
sourceWatch this location during animation.Electronic beam switching and shapingSlide19
SpaceX’s
original plan:Five lasers per satelliteFour connect to north-south neighborsOne connects to nearest east-west crossing satellite
Inter-satellite laser linksSpeed of light communicationCentral to fast long-distance linksNot yet ready for deploymentSlide20
Component reuse
Booster
2nd stageFairingSatellites inside the fairingRecovering boosters frequently fairing one time so farSlide21
Component reuse, today and tomorrowSlide22
Ms. Chief and Ms. Tree
Video
Fairing recoverySlide23
Very cool video
Booster recoveryThe Falcon Heavy rocket uses three boosters. Here two land simultaneously. (The third tried to land on a barge, but failed).Slide24
Debris remains an unsolved problem (but many people are working on it).
As of last night, 8,761 objects
had been launched into outer space and 5,293 were still in orbit (source).SpaceX alone has permission to launch over 12,000 satellites and has asked for 30,000 more.There are many ideas for dealing with debris, including the illustrated here from SpaceX (source).Slide25
LEO/GEO layer integration
Radio
frequencyLaserSource (49 second video)Latency > LEOFootprint > LEOSlide26
Patent
Hybrid leo/haps constellation for fixed broadband
Dynamically track the current availability, location, weather, bandwidth of reachable nodes and route traffic accordingly.Slide27
The network data model represents the nodes (vertices) and links (edges) in the topology and includes all accessible wired and wireless links. The data model is time-dynamic; each directional edge is associated with a set of time intervals of predicted accessibility with predicted link metrics throughout each accessible interval.
Source
Loon SDN: Applicability to NASA's next-generation space communications architectureBrian Barritt and Vint Cerfhttps://www.theverge.com/2019/1/31/18200879/alphabet-project-loon-sdn-networking-technology-telesat-satellite-dealLOON balloons tavel a lot slower than LEOsAre there controllers in every sat?Brian Barritt, Senior Engineer @ Loon will speak about hybrid infrastructure (loon/LEO?).https://www.satshow.com/http://www.circleid.com/posts/20190215_google_baloons_and_telesat_satellites/Slide28
Source
Multi-Layer integrationAn integrated Internet with terrestrial, atmospheric, LEO, MEO, GEO and deep-space
layersSES MEO/GEO integrationTelesat using Google Loon softwareDevising standards for 5G mobile-satellite integrationThis is the start of an ongoing project for many yearsSlide29
While making a lot of money to pay for itSlide30
Some radio news
Good news – higher frequency means faster transmission.Good news – higher frequency means smaller antennas.Bad news – higher frequency means more power or less distance.Worst
news – radio signals interfere with each other.Better news – technologies are being developed to mitigate interference.Programmable “smart” radios can detect interference and switch frequencies and power levels and focus and shape beams.Slide31
Communication between satellites and the ground
Radio frequencies are used between satellites and the ground.Sample radio spectrum allocations:AM radio: 535 to 1,700 KHzFM radio: 88 to 108 MHzKU band: 12 to 18
GHzMost satellites use Ku band frequencies today, but will use higher frequencies in the future.What happens when you change the channel on your TV set?Slide32
Most radio spectrum must be licensed
Do
WiFi radios uses licensed or unlicensed spectrum?Each country controls its own spectrum regulator. Ours is the Federal Communications Commission.the International Telecommunication Union, a UN agency, tries to keep spectrum use uniform. Slide33Slide34
Source
Do all Internet users have the same quality of service?
Is there a digital divide within the United States?Address the “digital divide”Slide35
Los Angeles to Punta Arena, Chile
Fewer, faster hops than fiber on long routes
SourceSlide36
Routing simulation
Watch here for simulation resultsSlide37
Inter-satellite linksSlide38
Teledesic failed in the late 1990s, what has changed?Slide39
Early geostationary satellite dish in rural India
Proposed low-Earth orbit satellite terminal with solar panels
Technology progress – ground station equipmentSlide40
Technology progress – communication
Beam forming
High speedLaser between satellitesSlide41
Booster landing videoSlide42
Reusability
Payload increases
Technology progress – rocketrySlide43
LEO optimismSlide44
SummarySlide45
Resources
Track the progress of the Internet-service satellite projects here.Slide46
I mentioned three leading companies
Which one(s) is/are pursuing the consumer market?Which one(s) is/are pursuing other markets?What are some non-consumer markets for satellite connectivityWhich is best suited to the consumer Internet service market: LEO, MEO or GSO?
Which has a larger footprint: LEO, MEO or GSO?Which has a longer latency time: LEO, MEO or GSO?What is latency a measure of?Self-study questionsSlide47
mPower
MEO plus over 50 GEOs Animated source
4,000 steerable, shapeable beams per satelliteFirst seven under constructionLaunch next year