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Explore the importance of bandwidth, spectrum allocation, and lift capability in satellite internet technology. Learn about solutions, key players, and the challenges of bridging the rural and global internet divide.
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Satellite InternetIt’s all about Bandwidth, Spectrum Allocation, and Lift Capability…J. Schmalzel, Ph.D., P.E.IEEE Life Fellow
Outline • Motivation • Rural and Global Internet Divide • Solutions • Key Players • The Constellations • Getting From Here to There • Concluding Observations
Motivation Eighth Measuring Broadband America, Fixed Broadband Report (12/2018) [1] • 3-200 Mbps was range of max advertised download speeds • 72 Mbps was median speed received by subscribers of participating ISPs • Most major broadband providers tested, measured download speeds ≥100% of advertised speeds during peak hours (1900-2300 local time). • Fourteen ISPs were evaluated in this report. Of these AT&T, Cincinnati Bell, Frontier and Verizon employed multiple different broadband technologies across the USA. Overall 17 different ISP/technology configurations were evaluated. Out of these only two performed below 90% for actual-to-advertised download speed. • In addition to providing download and upload speed measurements of ISPs, the report also presents a measure of how consistently ISPs provide their advertised speed with the use of the FCC “80/80metric,” which measures the minimum speed that at least 80% of subscribers experience at least 80% of the time over peak periods.
Motivation Internet Speed Test: http://speedtest.att.com/speedtest/ https://www.bandwidthplace.com/ Latency: Transit time of a packet from source to destination (varies with geographic + network distance) Download Speed: Aggregate Mbps of file download Upload Speed: Aggregate Mbps of file upload Example: 22APR2019 @2000 (GMT-5); ISP: Verizon Latency: 19ms Download Speed: 14.18 Mbps Upload Speed: 39.8 Mbps
In-Class Exercise Perform Internet Speed Test: http://speedtest.att.com/speedtest/ https://www.bandwidthplace.com/ Latency: Transit time of a packet from source to destination (varies with geographic + network distance) Download Speed: Aggregate Mbps of file download Upload Speed: Aggregate Mbps of file upload Example: Date/Time/ISP Latency: _____ms Download Speed: ______Mbps Upload Speed: ______Mbps
Motivation Definition of Broadband Internet: (2015) FCC raised the standard for high-speed Internet, voting that only connections with download speeds of ≥ 25 Mbps will qualify as broadband. The previous FCC definition of broadband was a download speed of ≥ 4 Mbps. The change, opposed by ISPs and Republican FCC commissioners, means nearly a fifth of Americans and more than half of those living in rural areas now lack access to high-speed Internet.
Motivation Existing Technologies Delivering Broadband Internet • Digital Subscriber Line (DSL): Asymmetric (ADSL)—higher download than upload; Symmetric (SDSL)—equal up/download speeds. Range from 100 kbps to several Mbps • Cable Modem: 1.5--+50 Mbps • Fiber: 10’s—100’s Mbps • Wireless: Typically local access to Internet service provided by another technology—e.g., distributing Internet over Wi-Fi from a residential Cable Modem • Satellite: 50 kbps – to 40 Mbps • Broadband over Powerlines (BPL): 100’s of kbps
In-Class Exercise Which of the Existing Technologies Delivering Broadband Internet do your currently use and/or formerly used? Include data rates if known. • Digital Subscriber Line (DSL): Asymmetric (ADSL)—higher download than upload; Symmetric (SDSL)—equal up/download speeds. Range from 100 kbps to several Mbps • Cable Modem: 1.5--+50 Mbps • Fiber: 10’s—100’s Mbps • Wireless: Typically local access to Internet service provided by another technology—e.g., distributing Internet over Wi-Fi from a residential Cable Modem • Satellite: 50 kbps – to 40 Mbps • Broadband over Powerlines (BPL): 100’s of kbps
The Rural Internet Divide • American Broadband Initiative (2/2019) [3]: • Streamline Federal permitting processes to make it easier for network builders and service providers to access Federal assets and rights-of-way, reducing the regulatory burden and expediting the deployment of broadband networks. • Leverage Federal assets such as towers, buildings, and land to lower the cost of broadband buildouts and encourage private entities to expand telecommunications infrastructure, especially in rural America. • Maximize the impact of Federal funding to better target areas of need, improve consistency, and provide incentives for State/local policies that efficiently and effectively leverage Federal dollars.
The Rural Internet Divide • Example small rural farm: 400 ac., 100-head cow/calf operation. • 30.798690, -88.982857 • Precision Agriculture [4] • Right applications • Right locations • Right times • Minimize trips around the field, soil compaction, etc. • Reduce fuel, pesticide, herbicide usage John Deere “Green Eggs & Ham” GPS Receiver (top of cab), [4].
The Global Internet Divide Internet Users Per 100 Inhabitants Key: Purple— Developed Green— Global Blue— Developing Source: Wikipedia.org, “Global Internet Usage”
In-Class Exercise • Count the degrees of separation between you as an urban broadband Internet user and someone(s) in rural American w/o broadband Internet access. • Do you know or work with anyone involved in Agriculture? • What Internet access speeds are available to users you identified in 1 and 2? • Repeat 1. for an international Internet user(s). • Repeat 3. for 4.
Technologies to Bring Broadband Internet to the Underserved • Fixed Wireless Internet: Tower-to-Fixed Receiver, 10 Mbps/1 Mbps U/D; 215 GB/mo; $50/mo. (AT&T) • AT&T AirGig: Wireless technique using mm waves guided by power lines. Microcell network offering up to 1 Gbps speeds https://www.youtube.com/watch?v=4ApPDP_DbGc • NGSO Satellite Constellations: 100’s – 1000 Mbps
Satellites: The Global Internet Solution • Early Internet constellation: Teledesic (McCaw, Gates, Alwaleed bin Talal), 1994-2003 • Ka Band (26.5-40 GHz) • Non-geosynchronous orbit (NGSO) • Originally 840 Sats at 700km—later 288 Sats at 1400km • 12 Orbit planes w/ 24 Sats/plane • Teledesic T1 (“BATSAT”) demonstration satellite launched 1998 • Existing satellite-based Internet provided by satellites in Geo-Synchronous Orbit (GSO) • ViaSat-1 (2011), 140 Gbps • HugesNet Jupiter (2012), EchoStar (2012), 100 Gbps • Challenge: High latency (up to 500ms)
Satellite Internet: The Global Internet Solution • United Nations Register of Objects Launched Into Outer Space: 4,987 • Online Index [5]
In-Class Exercise • Using the UN online satellite database, search for Teledesic T1. Determine as much about it as you can. • As for 1., search the database for MemSat. • As for 1., search the database for ViaSat-1. • …for HughesNet Jupiter • …for any other satellite you are interested in There are many compendiums of satellites on orbit—e.g.,
The Key Satellite Internet Players • The International Telecommunications Union (ITU) • The Federal Communication Commission (FCC) • One-Web • Amazon • Space-X • Boeing • TeleSat • LeoSat • Facebook (“PointView LLC”)
One-Web • Up to 2000 Sats • Feb 2019, Launch of first 6 Sats (ITU Spectrum allocation Use/Lose deadline); Launch vehicle: Soyuz • 1200 km orbit • Near term plans: 20 launches, up to 36 satellites/launch • Virgin Orbit using LauncherOne to loft 2 Sats per launch • 2019: 150 Sats (Note: Will also launch aboard Arienne 6) • 2020: 300 Sats total • 2021: 600 Sats total • Satellite fabrication: Exploration Park, FL (Partnership w/ KSC)
Amazon (“Kuiper Systems”) • Up to 3236 Satellites • 784 in 590km orbits • 1296 in 610km orbits • 1156 in 630km orbits • No FCC Application yet • Partnership with Lockheed-Martin to develop “AWS Ground Stations” • J. Bezos owns “Blue Origin,’ which gives Kuiper Systems potential orbital lift capability
Boeing • Filed with FCC in 2016 • 1396—2956 Satellites • No further movement
TeleSat • 292 Satellites in 1110—1325km orbits LeoSat • 108 Satellites in 1400km orbits
Space-X • 4,425 Total Satellites (some reports much larger) • 1110—1325km • 1583 Sats at 550km
Space-X’s FCC Mar 2018 Issue Full Title: Space Exploration Holdings, LLC, Application for Approval for Orbital Deployment and Operating Authority for the SpaceX NGSO Satellite System Document Type(s): MOO&A Bureau(s): International Description:Authorize Space Exploration Holdings, LLC to construct, deploy, and operate a proposed non-geostationary orbit (NGSO) satellite system comprising 4,425 satellites for the provision of fixed-satellite service (FSS) around the world DA/FCC #: FCC-18-38 File #:SAT-LOA-20161115-00118 FCC Record Citation: 33 FCC Rcd 3391 (4) FCC Record:FCC-18-38A2_Rcd.pdf SUGGESTED READING Subsequent approval for almost 7,518 (Nov 2018) more—a total of 12,000(!)
StarLink [9, 10] • First phase to begin 6/2019 • 1584 Sats, 1500km Altitude • 24 Orbital Planes • 66 Sats per plane • View Sim by Prof. Mark Hadley, Univ. College, UK https://www.youtube.com/watch?v=AdKNCBrkZQ4 • LEO decay estimated to require replacement of 20% annually Source: [9]
StarLink Communication Technologies • On-orbit satellite-to-satellite • Laser optical links • Link acquisition and maintenance • Earth Station-to-Satellite • Ka (26.5—40GHz), Ku (12—18GHz), V (40—70GHz) • Uplink: 37.5—42GHz • Downlink: 47.2—51.4GHz • [11] k=1.38E-23 J/K • Spectrum usage: See Slide 36 of [11] Source: [9]
StarLinkComm Technologies • Ground Station-to-Terrestrial infrastructure • Fiber backbone • Individual Base Station • Base Station • Phased-array antenna (e.g., Satixfy [7]) • Capable of tracking multiple satellites • 1 Gbps data rate
Getting There (is Half the Fun!) • µ is Standard Gravitational Parameter, m3/s2 Earth: 3.9860E14 Mars: 4.2828E13 Moon: 4.9049E12 • r is radius between mass, M, and satellite mass, m (Since Me= 5.98E24 kg >> msat, this is a 1-Body case) • T is orbital period (Note: Keppler’s 3d Law solves for elliptic case, a)
Example (Sat Altitude = 1500km)v= 7.1 km/s, T= 7038s • µ is Standard Gravitational Parameter, m3/s2 Earth: 3.9860E14 Mars: 4.2828E13 Moon: 4.9049E12 • r is radius between mass, M, and satellite mass, m (Since Me= 5.98E24 kg >> msat, this is a 1-Body case) • T is orbital period (Note: Keppler’s 3d Law solves for elliptic case, a) Ref: [8]
In-Class Exercise • Calculate velocity and period for the ISS Assume altitude of 400 km v= T= • You have decided to propose a constellation of satellites to orbit Mars to provide Internet to future Martians. What would v and T be for satellites placed in orbit at an altitude of 1500 km? • Your investors want to try the array in Moon orbit first. Recalculate.
Space-X: Falcon (Heavy) • Space-X needs to launch 44 Starlink Satellites/mo for 60 months to maintain FCC spectrum allocation. (In addition to satisfying their other launch customers.) • FCC requires 50% deployment w/in 6 yrs; balance w/in 9 yrs.; waivers possible • Satellite mass: 100-500kg/ea • Space debris concerns: NASA wants >90% deorbit reliability for the constellation
Falcon (Heavy) • 63,800 kg to LEO • April 11, 2019 Launch, https://www.nytimes.com/2019/04/11/science/falcon-heavy-launch-spacex.html • 1st Stage Landinghttps://www.nytimes.com/2019/04/11/science/falcon-heavy-launch-spacex.html 1:32, 3:35
Cost to Loft 1kg to orbit • ROT: $10,000/lbm $20k/kg • Everyone is trying to lower that cost Homework: What do you estimate Space-X’s mass loft cost to be? What is the impact of reusable boosters? Complete the design of the StarlinkComm System Develop an immersive simulation for Starlink
Thank You! Questions/Discussion
References • FCC Eigth Measuring Broadband America, Fixed Broadband Report, 14 DEC 2018, https://www.fcc.gov/reports-research/reports/measuring-broadband-america/measuring-fixed-broadband-eighth-report • Types of broadband connections, https://www.fcc.gov/general/types-broadband-connections • American Broadband Initiative, https://www.engadget.com/2019/02/13/american-broadband-initiative-rural-internet-us-government/ • Precision Agriculture, https://spectrum.ieee.org/tech-history/silicon-revolution/john-deere-and-the-birth-of-precision-agriculture • Online index of orbiting objects, http://www.unoosa.org/oosa/osoindex/search-ng.jspx?lf_id= and https://www.ucsusa.org/nuclear-weapons/space-weapons/satellite-database • One-Web, https://spacenews.com/first-six-oneweb-satellites-launch-on-soyuz-rocket/ • Satixfy phased array antenna, https://spacenews.com/satixfy-prepares-release-of-flat-panel-antennas-this-year/
References… • https://en.wikipedia.org/wiki/Standard_gravitational_parameter • News article about Starlink, https://www.universetoday.com/140539/spacex-gives-more-details-on-how-their-starlink-internet-service-will-work-less-satellites-lower-orbit-shorter-transmission-times-shorter-lifespans/ • More details about Starlink, https://arstechnica.com/information-technology/2018/11/spacex-gets-fcc-approval-for-7500-more-broadband-satellites/ • COL J. Keesee, “Satellite Communication,” MIT Open Source Courseware, https://ocw.mit.edu/courses/aeronautics-and-astronautics/16-851-satellite-engineering-fall-2003/lecture-notes/l21satelitecomm2_done.pdf