Internet for all: Stratospheric solutions by Google loon and Facebook drone Course project for Wireless Technologies course at Northwestern University's MSIT program

1. Northwestern University
McCormick School of Engineering and Applied Science
Master of Science in Information Technology
MSIT 413: Wireless Technologies
Internet for All: Stratospheric solutions by Google
Loon and Facebook Drone
Abdulsalam A, Hang Li, Jie Zhang
March 16, 2014
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2. Table of Content
Introduction
Figure 1: Top 20 connected countries, by price and speed
Stratospheric Solutions
Overview
Table 1: Loon vs Drone
Google Project Loon
Engineering/How Loon Works
Stratospheric Environment
Figure 2: Wave current and balloons movement
Figure 3: Stratosphere by altitude
Balloon
Figure 4: Loon vs Drone
Power
Figure 5: Solar panel for Loon
Figure 6: Battery insulation
Circuitry and Transmission
Figure 7: Patent circuitry of Loon
Figure 8: Original on-board circuitry for early pilots
Connectivity
Figure 9: Mesh network of Loon
Figure 10: Dual polarized dipole antenna for the receiver
Technical considerations for Project Loon
Facebook Drone
Figure 11: Titan Solara Drone
Regulatory/Political Issues
Cost and what next ?
Criticisms
Conclusion
Appendix
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3. Introduction
Over the past 25 years of internet and evolution of the world wide web, some population of
the world have enjoyed the benefits and goodies of online lifestyles while other majority
have not experienced an hour of internet. The thought that everyone is on the internet is
very wrong, and this is true, because for every one connected person, there are two
unconnected people.
The way the world works is changing; we used to live in a resource based economy where
things are shared or traded, but the world is now a knowledge economy, which means we
can share knowledge and information almost freely to improve our lives. The imagination of
how a connected world can provide basic information such as primary health care data,
education and research, environmental data, media and entertainment, etc to the rest of the
world is a serious concern, because the internet is the backbone of the knowledge economy.
Indeed, if everyone had access to basic information and tools, then everyone would benefit
from the creativity, innovation and ideas that everyone embodies.1
The reason behind the access challenge is obvious; the high cost of providing internet
connectivity, due to the level of technology and current infrastructure. The paradox is that;
as it is ineffective and costly for ISPs to expand especially into rural, low economic regions,
so also people living below the poverty line of $1 per day can not afford the highly priced
internet service. Even in the developed world, where most have disposable incomes to join
this knowledge economy, the cost and speed of access is still a challenge. Figure 1 belows
shows the top 20 connected nations, and its obvious that no appreciable throughput can be
achieved for $1 per month.
Figure 1: Top 20 connected countries, by price and speed
1
Making internet affordable by Mark Zuckerberg - http://www.youtube.com/watch?v=AdXwthh-xLQ
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4. The challenge poses the idea of finding alternate solutions, that can balance the
ever-growing needs of global development. Interestingly, there has been some research
works, trying to solve the problem. There are also several papers presented in the past 10
years on scalable approaches, that will either improve current technologies or completely
disrupt with something new.
However, five interesting ideas may likely make a difference if successful . These wireless 2
solutions are innovative and scalable;
● Low-orbiting satellites
● Metamaterial antennas
● Balloons
● Drones
● TV white space
While low-orbiting satellites are almost the same as satellite communication systems, there
are good business reasons for the approach. Also, metamaterial antennas are not new, but
are redefined for cheap usage in high-powered transceivers or base station . TV whitespace, 3
is quite a challenge, because it tries to solve the problem from the spectrum standpoint,
which becomes policy and change issues. TV white space lobbyists are trying to re-acquire
unused TV frequencies for wireless internet service and improve spectrum efficiency.
Two keys solutions are referred to as stratospheric solutions . The concepts tries to 4
address; Ubiquity, True Coverage, Reliability, Affordability and Scalability. Importantly, to
note is that the current iterations of these projects are funded not by Government or
research labs, but by vested interests that have excess funds to support research and
development to fruition. This is also obvious, because these companies have markets to
cover and gain enough potentials for its businesses.
Google Inc. (Google X lab) is in active research on using Balloons to activate wireless
internet connectivity to everyone, with its Project Loon . Currently, in its pilot stage, 30 5
balloons floated in New Zealand in Summer of 2013, show positive results. Google strongly
believes that the stratosphere is common to everyone and with the amount of data available,
this medium can be help solve the internet divide.
Similarly, after the demonstration of a drone-like airship called stratellite, by a Mexican
company, Titan Aerospace; with the capability to carry wireless communication devices,
Facebook Inc. is convinced that investing in such a companies promises further development
of an ubiquity solution. While the drones are almost ready for commercial purposes, there
are continued efforts to integrate these drones with current communication infrastructure.
The project intends to highlight some of the features and engineering behind the Project
Loon and Facebook Drone (Titan Solara 60) and detail some regulatory, economics and
policy issues involved to achieve internet access for all.
2
http://spectrum.ieee.org/telecom/wireless/five-ways-to-bring-broadband-to-the-backwoods
3
http://spectrum.ieee.org/telecom/wireless/intellectual-ventures-invents-beamsteering-metamaterials-antenna
4
http://spectrum.ieee.org/aerospace/satellites/an-eye-in-the-sky
5
www.google.com/loon
4

5. Stratospheric Solutions
Overview
Google Loon Facebook Drone
Transceiver Medium Balloon Drone
High altitude 20 miles (32 km) 11 miles (18km)
Duration 100 days 5 years
Coverage 1,250 km2
17,000 km2
Motion Speed 8-32 km/h 104.5 km/h
Spectrum 2.4GHz and 5.8GHz 5.8GHz
Data rate less than 0.1Gbps greater than 1 Gbps
Research and Development In-house (X labs) External (Titan Aerospace)
Additional services VOIP Surveillance
Table 1: Loon vs Drone
Google Project Loon
Loon is currently designed to work at 3G speed over unlicensed 2.4GHz and 5.8GHz
spectrum, floating in the stratosphere high above aircrafts, using helium filled
balloon.
Engineering/How Loon Works
Stratospheric Environment
Because the wind below 10km of altitude is not favorable, and because balloons can
not be positioned even above that tropopause, an algorithm is developed to control
movement or flow of the balloons based on national wind data, just like the sailing of
boat to shoreline, adjusting them along right currents in the direction of waves of the
wind.
Figure 2: Wave current and balloons movement
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6. Figure 3 below shows altitude levels above the atmosphere and somewhat indicate
that theoretically, radio waves behave well in free space, with no interference of
signal, and power is attenuated by path loss coefficient lower than 2
Figure 3: Stratosphere by altitude
Balloon
The material for the manufacturing the balloon is polyethene, simply 3 times thicker
than typical bread wrapper ~0.076mm (0.030in). These balloons have super
pressure design that can withstand harsh UV radiation and temperatures as low as
-58F. When inflated, each balloon has a dimension of about 50 feet wide, and 40 feet
tall. Also, the balloons have customized electronic air-pump system that control
mixture of helium and air, as the balloon ascend or descend in altitude. In case of
failure, a parachute is installed for safe landing of the payload. Figure 2 below shows
a section of a fully inflated balloon. The balloon released be circling the globe
continuously along the 40th parallel.
Figure 4: Loon vs Drone
Power
To power the circuitry and motion of the balloons, the only intuitive solution is solar
energy. However, the temperature at this altitude is really low (-100F), and the
radiation of sun is only for a fraction of the day. This is a challenge for
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7. solar-powered batteries that allow each balloon to transmit signals, run the heater so
the electronics don’t freeze, and change altitudes to navigate . Alternate or backup 6
solution are therefore required. Figure 5 below shows a proposed 5x5 feet array of
solar panels, that will power 100W system and charge batteries for 4-5 hours.
Figure 5: Solar panel for Loon
An earlier iteration of Loon, shows that Lithium ion batteries were initially
implemented for dark hours. See Figure 7. However, the system is built to be
self-sustaining and fully employs renewable scheme. To keep the batteries warm
enough to function efficiently, despite the cold environment, special casings and
insulation are designed and tested for true proof. Figure 6 is a shining insulation that
reflects heat energy by radiation7
Figure 6: Battery insulation
6
https://plus.google.com/+ProjectLoon/photos/photo/5896519904108748322
7
https://www.youtube.com/watch?v=EPDzpxFkTvM
7

8. Circuitry and Transmission
Each balloon carries a payload of about 10 kg, including but not limited to radio
antenna, several sensors, altitude control system, processor chips and batteries.
Figure 7 is a possible patent diagram of the circuitry . The on-board antenna uses an 8
Ubiquiti Network Rocket M2 as a WIFI transceiver. A customized Linux OS is also
loaded on a processor chip to manage and transmit network and location data. The
OS is loaded with software that can logged onto remotely via the web.
Figure 7: Patent circuitry of Loon
Third iteration of original circuitry for early pilots is shown below in figure 7;9
Figure 8: Original on-board circuitry for early pilots
8
http://www.patentbolt.com/2013/11/googles-high-altitude-balloon-network-called-project-loon-is-revealed-in-new-
patent.html
9
https://plus.google.com/+ProjectLoon/photos/photo/5964725567087891410
8

9. Connectivity
There are several ground stations with transceivers similar to that on the balloon, but
they are high-powered Ubiquiti AirMax/Rocket M5 (operating at 5.8Ghz). The 10
network is designed as a mesh layout to ensure reliability. A ground station already
connected via either fiber or other backbone infrastructure to the internet, beams
signal to any nearby balloon. The first balloon that receives the signal, then 11
forwards or hops the signal up to 5 other balloons on its same path in sequence, a
distance of about 100 km (62 miles). Figure 9 shows the mesh structure of Loon
Figure 9: Mesh network of Loon
Each balloon then hops the WIFI signal to ground users with coverage of about 1,256
km2
(780 sq miles), in context the twice the size of New York City. Users can receives
signal via smartphones or customized dual-polarization dipole antenna through an
access point. Figure 10 shows current iteration of the ground receiver antenna.
Figure 10: Dual polarized dipole antenna for the receiver
10
http://community.ubnt.com/t5/The-Lounge/Internet-for-all/m-p/491445#M24270
11
http://www.google.com/loon/how/
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10. Technical considerations for Project Loon
Radio: Loon’s current radio design negatively interfere on the ground in more
developed areas, due to fading, scattering and Rayleigh effects. This would definitely
affect other local WIFI signals. There would be so much signals and noise in the
airwaves, that may require changes in regulation and implementation of other
technologies.
Connectivity: The WIFI card (Rocket M5) is assumed to be MIMO 802.11a/g/n
standard and uses TDMA, that can deliver 150 Mbps throughput at +50 km, but still 12
the latency is pretty high (about 700+ms), this may be due to the moving balloons.
This may not be a viable option for VOIP service, which could motivate adoption of the
service. Generally, some salient issues still exist, such as interference management
between balloons; handoff between balloons; fading from the ground stations;
latency management and error control.
Facebook Drone
Confirmed reports, have it that Facebook is likely going to acquire a Mexico-based
company ; Titan Aerospace for $60m. Titan’s solar-powered drones, which can 13
reportedly stay airborne for five years, can help Facebook achieve its goal of
providing Internet access around the world. In theory, a solar-powered drone
capable of withstanding long flights at high altitude. Titan had demonstrated it debut
Solara 50 and 60, in 2013, showing possibility to provide communication services,
from just above the Tropopause (close to the atmosphere), 60,000 feet altitude that
the FAA doesn't control. Facebook is said to be especially interested in the Solara 60,
a featherweight aircraft built of composite materials that the New Mexico-based
company claims can maintain an altitude of 65,000 feet for years without refueling,
thanks to thousands of solar cells blanketing the aircraft.
Figure 11: Titan Solara Drone
12
http://dl.ubnt.com/datasheets/rocketmgps/RocketM_Ti_DS.pdf
13
http://www.theverge.com/2014/3/7/5473692/facebook-drone-titan-aerospace-project-loon
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11. Solara 60
Solara are mounted with both LOS and BLOS (Beyond Line of Sight) small, low cost
radio repeaters and/or transmitters. The repeater receives the signals from
transmitters on the selected radio frequency (RF) channel and then re-transmits them
on another frequency to a receiver. The Solara 60 can complete most of the same 14
functions as an orbital satellite, but is cheaper and more versatile. It can also stay at
an altitude of 20 km for up to five years, without ever having to come back down and
refuel. The platform works exactly like regular satellite communication systems but
are better. Solara can last up to 5 years, has 120 ft wingspan and 50 ft long, has
speeds greater than 1 Gbps, has larger coverage than 1018 sq miles and efficient
power management .15
The Solara offers about an 18-mile radius of coverage—easily covering all of New
York City's five boroughs, as shown in the map below. A "constellation" of Solara craft
could create a persistent communication network for disaster relief efforts or could
provide long-term services.
Regulatory/Political Issues
The biggest obstacles for these projects are not definitely technology or funding, but
regulation and politics. Mesh networks are nothing new, and dirigibles have been around
since the time of Graf Zeppelin . The minefield here is entirely political. Both Google and 16
Facebook, need to maneuver some critical issues. First, is the use of airspace; secondly is use
of the ISM unlicensed spectrum; thirdly is fear of insecurity and Spying.
14
http://wordlesstech.com/2013/08/22/solara-an-affordable-alternative-to-satellites/
15
http://www.wired.com/business/2014/03/facebooks-drones-launch-race-airborne-internet/
16
http://gigaom.com/2013/06/21/project-loon-googles-biggest-obstacle-isnt-technology-its-politics/
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12. Airspace
This is the portion of the atmosphere controlled by a country above its territory,
including its territorial water, more generally, any specific three-dimensional portion
of the atmosphere. There are many rules regarding airspace and who controls it, and
also disagreements as to how far (up) such control extends. Although, space is still an
open frontier, loosely regulated by international treaties, most governments consider
the stratosphere above them their sovereign airspace, which is why they shoot down
spy planes that venture into it.
Spectrum
The signals currently propagate in the unlicensed ISM spectrum (2.4 and 5.8GHz) the
pilot period. The Internet signals travel in the unlicensed spectrum, which means
Google and Facebook drone do not have to go through the onerous regulatory
processes required for Internet providers using wireless communications networks
or satellites during experiment.
However, the scenario is not as simple as WiFi. When Google or Facebook become a
global ISP; actually providing or selling internet service, like any communications
service provider are regulated and governments will likely want some say in how that
access is offered, what they can charge, and ultimately whom they are allowed to
connect. Also It can’t just use any old spectrum either. It will have to convince
hundreds of different regulators to agree on a unified band or ride over an existing
one. But the scope and range of Google Loon or Facebook Drone network will likely
require dedicated airwaves.
Security
This is the part that governments are concerned most about. It revolves around
countries and citizens’ safety to a large extend. With recent NSA and data theft/leak
incidences, both Google and Facebook may need to work harder to assure the
countries it is working with that the network is secure and agree to terms and
conditions of these countries. This is paramount, because some country leaders,
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13. prefer to be out of internet, than to be attacked by the US and its allies.
Cost and what next ?
The cost for deploying a single balloon is not too high, but Google is planning to fly
about 70,000 balloons to be economically logical on a global scale. The estimated cost
for the pilot in New Zealand for only 30 balloons is about $1.8 million. However, the
cost alone for a single UAV manufactured by Titan is about $2million. This cost does
not include the internet service.
Item Cost ($)
Polyethylene plastic envelopes 4,000
Helium gas 2,000
Solar panel 500
Navigation control system 1,000
Equipment box 12,000
19,500
Total of cost of balloons(30) $585,000
Station construction and
equipment installation
$1,200,000
Estimated Total (for new
zealand pilot)
$1,785,000
The difference in economics is the area covered by Google (about 780 sq mile), while
Facebook Drone may even spend more for the projected 1080sq mile. There is also
additional cost for private WIFI licenses which will be dictated by different
governments.
Research continues and patents are been filed everyday to quickly commercialize the
project. Some of the next phases for Google, is work on efficient deployment
mechanisms. Figure 12 shows a system filed for patient. A truck that deliver balloons
and automatically launch the system without human touch.
Figure 12a: Solar powered truck Figure 12b: Balloon self-deployment
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14. Criticisms
● Temple University communications professor Patrick Murphy warned of
mixed consequences, pointing to China and Brazil as places where Internet
service promoted democratic principles but also contributed to a surge in
consumerism that has resulted in environmental and health problems.
● There are some opposing voices such as Bill Gates, who has questioned
whether Google's Project Loon, an effort to bring giant internet-giving
balloons to less-developed countries, is really that good of an idea. During an
interview with Bloomberg Businessweek, Gates was asked whether he thought
bringing internet to parts of the world would help solve problems. "When
you're dying of malaria, I suppose you'll look up and see that balloon, and I'm
not sure how it'll help you."
Conclusion
Indeed in the nearest future, everyone may eventually have affordable high-speed internet.
Both Google Inc and Facebook Inc have devoted themselves to providing worldwide internet
access, and the technologies seem promising. Though, the world may hold different opinions
about such research and solutions, it keep technology enthusiasts excited that after all there
is hope to make the world a global knowledge economy. And the competition between the
two company would make stratospheric solution a possibility.
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15. Appendix
Rocket M2 and M5 datasheet
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