Starlink satellites Report for alls.pptxBloomsTech
Starlink is a satellite internet constellation operated by SpaceX, providing high-speed, low-latency internet access to users around the world. This report details the engineering aspects of Starlink, including its design, deployment, and operation. It also discusses the potential benefits and challenges of Starlink technology.
Starlink is a constellation of thousands of small satellites orbiting Earth in low-Earth orbit (LEO). These satellites provide internet access to users on the ground by relaying signals between the satellites and ground stations. Starlink was founded by Elon Musk in 2015 with the goal of providing internet access to underserved areas of the world.
this presentation is about satellite communication which includes working of gps ,vsat ,frequency bands ,needs of communication satellite ,types of satellite ,working ,orbits ,elements involved in working ,transponder ,satellite control center ,satellite network
APNIC Foundation, presented by Ellisha Heppner at the PNG DNS Forum 2024APNIC
Ellisha Heppner, Grant Management Lead, presented an update on APNIC Foundation to the PNG DNS Forum held from 6 to 10 May, 2024 in Port Moresby, Papua New Guinea.
Registry Data Accuracy Improvements, presented by Chimi Dorji at SANOG 41 / I...APNIC
Chimi Dorji, Internet Resource Analyst at APNIC, presented on Registry Data Accuracy Improvements at SANOG 41 jointly held with INNOG 7 in Mumbai, India from 25 to 30 April 2024.
More Related Content
Similar to VNNIC Internet Day 2023: On LEOs and Starlink
Starlink satellites Report for alls.pptxBloomsTech
Starlink is a satellite internet constellation operated by SpaceX, providing high-speed, low-latency internet access to users around the world. This report details the engineering aspects of Starlink, including its design, deployment, and operation. It also discusses the potential benefits and challenges of Starlink technology.
Starlink is a constellation of thousands of small satellites orbiting Earth in low-Earth orbit (LEO). These satellites provide internet access to users on the ground by relaying signals between the satellites and ground stations. Starlink was founded by Elon Musk in 2015 with the goal of providing internet access to underserved areas of the world.
this presentation is about satellite communication which includes working of gps ,vsat ,frequency bands ,needs of communication satellite ,types of satellite ,working ,orbits ,elements involved in working ,transponder ,satellite control center ,satellite network
APNIC Foundation, presented by Ellisha Heppner at the PNG DNS Forum 2024APNIC
Ellisha Heppner, Grant Management Lead, presented an update on APNIC Foundation to the PNG DNS Forum held from 6 to 10 May, 2024 in Port Moresby, Papua New Guinea.
Registry Data Accuracy Improvements, presented by Chimi Dorji at SANOG 41 / I...APNIC
Chimi Dorji, Internet Resource Analyst at APNIC, presented on Registry Data Accuracy Improvements at SANOG 41 jointly held with INNOG 7 in Mumbai, India from 25 to 30 April 2024.
APNIC Policy Roundup, presented by Sunny Chendi at the 5th ICANN APAC-TWNIC E...APNIC
Sunny Chendi, Senior Advisor, Membership and Policy at APNIC, presents 'APNIC Policy Roundup' at the 5th ICANN APAC-TWNIC Engagement Forum and 41st TWNIC OPM in Taipei, Taiwan from 23 to 24 April.
DDoS In Oceania and the Pacific, presented by Dave Phelan at NZNOG 2024APNIC
Dave Phelan, Senior Network Analyst/Technical Trainer at APNIC, presents 'DDoS In Oceania and the Pacific' at NZNOG 2024 held in Nelson, New Zealand from 8 to 12 April 2024.
'Future Evolution of the Internet' delivered by Geoff Huston at Everything Op...APNIC
Geoff Huston, Chief Scientist at APNIC deliver keynote presentation on the 'Future Evolution of the Internet' at the Everything Open 2024 conference in Gladstone, Australia from 16 to 18 April 2024.
IP addressing and IPv6, presented by Paul Wilson at IETF 119APNIC
Paul Wilson, Director General of APNIC delivers a presentation on IP addressing and IPv6 to the Policymakers Program during IETF 119 in Brisbane Australia from 16 to 22 March 2024.
draft-harrison-sidrops-manifest-number-01, presented at IETF 119APNIC
Tom Harrison, Product and Delivery Manager at APNIC presents at the Registration Protocols Extensions working group during IETF 119 in Brisbane, Australia from 16-22 March 2024
Benefits of doing Internet peering and running an Internet Exchange (IX) pres...APNIC
Che-Hoo Cheng, Senior Director, Development at APNIC presents on the "Benefits of doing Internet peering and running an Internet Exchange (IX)" at the Communications Regulatory Commission of Mongolia's IPv6, IXP, Datacenter - Policy and Regulation International Trends Forum in Ulaanbaatar, Mongolia on 7 March 2024
APNIC Update and RIR Policies for ccTLDs, presented at APTLD 85APNIC
APNIC Senior Advisor, Membership and Policy, Sunny Chendi presented on APNIC updates and RIR Policies for ccTLDs at APTLD 85 in Goa, India from 19-22 February 2024.
Lao Digital Week 2024: It's time to deploy IPv6APNIC
APNIC Development Director Che-Hoo Cheng presents on the importance of deploying IPv6 at the Lao Digital Week 2024, held in Vientiane, Lao PDR from 10 to 14 January 2024.
Italy Agriculture Equipment Market Outlook to 2027harveenkaur52
Agriculture and Animal Care
Ken Research has an expertise in Agriculture and Animal Care sector and offer vast collection of information related to all major aspects such as Agriculture equipment, Crop Protection, Seed, Agriculture Chemical, Fertilizers, Protected Cultivators, Palm Oil, Hybrid Seed, Animal Feed additives and many more.
Our continuous study and findings in agriculture sector provide better insights to companies dealing with related product and services, government and agriculture associations, researchers and students to well understand the present and expected scenario.
Our Animal care category provides solutions on Animal Healthcare and related products and services, including, animal feed additives, vaccination
Bridging the Digital Gap Brad Spiegel Macon, GA Initiative.pptxBrad Spiegel Macon GA
Brad Spiegel Macon GA’s journey exemplifies the profound impact that one individual can have on their community. Through his unwavering dedication to digital inclusion, he’s not only bridging the gap in Macon but also setting an example for others to follow.
Meet up Milano 14 _ Axpo Italia_ Migration from Mule3 (On-prem) to.pdfFlorence Consulting
Quattordicesimo Meetup di Milano, tenutosi a Milano il 23 Maggio 2024 dalle ore 17:00 alle ore 18:30 in presenza e da remoto.
Abbiamo parlato di come Axpo Italia S.p.A. ha ridotto il technical debt migrando le proprie APIs da Mule 3.9 a Mule 4.4 passando anche da on-premises a CloudHub 1.0.
1.Wireless Communication System_Wireless communication is a broad term that i...JeyaPerumal1
Wireless communication involves the transmission of information over a distance without the help of wires, cables or any other forms of electrical conductors.
Wireless communication is a broad term that incorporates all procedures and forms of connecting and communicating between two or more devices using a wireless signal through wireless communication technologies and devices.
Features of Wireless Communication
The evolution of wireless technology has brought many advancements with its effective features.
The transmitted distance can be anywhere between a few meters (for example, a television's remote control) and thousands of kilometers (for example, radio communication).
Wireless communication can be used for cellular telephony, wireless access to the internet, wireless home networking, and so on.
1. On LEOs and Starlink
Geoff Huston AM
Chief Scientist, APNIC
November 2023
2. screenshot from starwatch app
Screenshot: https://asia.nikkei.com/Business/Telecommunication/Elon-Musk-s-Starlink-launches-satellite-internet-service-in-Japan
Screenshot - https://www.theverge.com/2022/8/25/23320722/spacex-starlink-t-mobile-satellite-internet-mobile-messaging
LEOs in the News
3. Newtonian Physics
• If you fire a projectile with a speed
greater than 11.2Km/sec it will not
fall back to earth, and instead head
away from earth never to return
• On the other hand, if you incline the
aiming trajectory and fire it at a
critical speed it will settle into an
orbit around the earth
• The higher the altitude, the lower
the orbital speed required to
maintain orbit
4. Solar Radiation Physics
• The rotating iron core of the
Earth produces a strong
magnetic field
• This magnetic deflects solar
radiation – the Van Allen Belt
• Sheltering below the Van
Allen Belt protects the
spacecraft from the worst
effects of solar radiation,
allowing advanced
electronics to be used in the
spacecraft
6. Low Earth Orbit
• LEO satellites are stations between 160km and 2,000km in altitude.
• High enough to stop it slowing down by “grazing” the denser parts of the earth’s ionosphere
• Not so high that it loses the radiation protection afforded by the Inner Van Allen belt.
• At a height of 550km, the minimum signal propagation delay to reach the satellite and back is 3.7ms,
at 25o it’s 7.5ms, and at the horizon it’s 18ms
screenshot from starwatch app
Image - spacex
7. Starlink Constellation
If you use a minimum angle of elevation of 25o then at an
altitude of 550km each satellite spans a terrestrial
footprint of no more than ~900Km radius, or 2M K2
At a minimum, a LEO satellite constellation needs 500
satellites to provide coverage of all parts of the earth’s
surface
For high quality coverage the constellation will need 6x-
20x that number (or more!)
7
8. Starlink Constellation
• 4,276 in-service operational spacecraft, operating at an altitude of 550km
https://satellitemap.space/
8
9. So LEOs are “interesting”!
• They are very close to the Earth – which means:
• They don’t need specialised high-power equipment to send and receive
signals
• Even hand-held mobile devices can send and receive signals with a LEO!
• They can achieve very high signal speeds
• It’s a highly focussed signal beam
• They are harder to disrupt by external interference
• But you need a large number of them to provide a continuous service
• The extremely host cost of launching a large constellation of LEO
spacecraft has been the major problem with LEO service until recently
• Which is why Motorola’s Iridium service went bankrupt soon after launch
10. What’s changed recently?
• SpaceX’s reusable rocket technology has slashed the cost of lifting
spacecraft into low earth orbit
SpaceX
https://ourworldindata.org/grapher/cost-space-launches-low-earth-orbit
Cost/Kg
(log
scale)
Time
12. Tracking a LEO satellite
550km
27,000 km/h
Satellite
horizon to horizon: ~5 minutes
13. Looking Up
Starlink tracks satellites with a minimum
elevation of 25o.
There are between 30 – 50 visible Starlink
satellites at any point on the surface
between latitudes 56o North and South
Each satellite traverses the visible aperture
for a maximum of ~3 minutes
13
14. Starlink Scheduling
• A satellite is assigned to a user terminal in 15 second time slots
• Tracking of a satellite (by phased array focussing) works across 11
degrees of arc per satellite in each 15 second slot
client
11o
15 seconds
14
15. Starlink Scheduling
• Latency changes on each
satellite switch
• If we take the minimum
latency on each 15 second
scheduling interval, we can
expose the effects of the
switching interval on latency
• Across the 15 second interval
there will be a drift in latency
according to the satellite’s
track and the distance relative
to the two earth points
• Other user traffic will also
impact on latency, and also
the effects of a large buffer in
the user modem
16. Starlink Spot Beams
• Each spacecraft 2,000 MHz of spectrum for user downlink and splits it into 8x channels
of 250 MHz each
• Each satellite has 3 downlink antennas and 1 uplink antennas, and each can do 8
beams x 2 polarizations, for a total of 48 beams down and 16 up.
16
“Unveiling Beamforming Strategies of Starlink LEO Satellites”
https://people.engineering.osu.edu/sites/default/files/2022-10/Kassas_Unveiling_Beamforming_Strategies_of_Starlink_LEO_Satellites.pdf
19. Reported Capacity
& Latency
• This is going to present some interesting issues for conventional TCP
• TCP uses ACK pacing which means it attempts to optimize its sending
rate over multiple RTT intervals
• The variation in latency and capacity occurs at high frequency, which
means that TCP control is going to struggle to optimize itself against a
shifting target
19
27. Protocol Considerations
• Starlink services have two issues:
• Very high jitter rates
• High levels of micro-loss
• Loss-based flow control algorithms will over-react and pull back the
sending rate over time
• Short transactions work very well
• Paced connections (voice, zoom, video streaming) tend to work well most of
the time
• Bulk data transfer, not so much
• You need to move to less loss-sensitive flow control algorithms, such
as BBR to get good performance out of these services
28. What about Starlink Gen2?
• These satellites are larger, heavier and operate at a higher power level
• More bandwidth available, better SNR, and high achievable data
speeds
• Multiple orbital plans at a collection of discrete altitudes
• Incorporates 5G cellular services
• Will use inter-satellite laser connectors to support packet routing
across satellites – few details as yet
29. I don’t want to leave you with
the wrong impression of Starlink
Starlink is perfectly acceptable for:
• short transactions
• video streaming
• conferencing
• The service can sustain 10 – 20Mbps delivery for long-held sessions
• The isolated drop events generally do not intrude into the session state
• And it can be used in all kinds of places where existing wire and mobile
radio systems either under-perform or aren’t there at all!
• Its probably not the best trunk infrastructure service medium, but it’s a
really good high speed last mile direct retail access service, particularly for
remote locations!
• Its also very challenging to jam!