An illustrated guide to mobile technology

PART I: HISTORY OF THE MOBILE PHONEFROM SMOKE SIGNALS TO WIRELESS RADIO FROM TRAINS, SHIPS AND TANKS TO THE MOTOR CAR – THE ERA OF ZERO-G FROM THE CAR TO THE STREETS AND INTO THE SHIRT P

AN ILLUSTRATED GUIDE

TO MOBILE TECHNOLOGY

Copyright © 2015 Sachin Date

All rights reserved

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BISAC Category: TEC061000 TECHNOLOGY & ENGINEERING / Mobile & Wireless Communications

Published by Amazon Digital Services, Inc.

To my wife Aditi, and son Nikhil, Without your help and support, this book would have remained just an idea in my mind.

PART I: HISTORY OF THE MOBILE PHONE

FROM SMOKE SIGNALS TO WIRELESS RADIO

FROM TRAINS, SHIPS AND TANKS TO THE MOTOR CAR – THE ERA OF ZERO-G FROM THE CAR TO THE STREETS AND INTO THE SHIRT POCKET – THE ERA OF 1G FROM ANALOG TO DIGITAL – 2G AND BEY OND

THE BIRTH OF THE SMART PHONE

PART II: MOBILE APPLICATIONS

CONSUMER MOBILE APPLICATIONS

THE FIVE STEP OBSTACLE RACE TO SUCCESS

BUSINESS AND REVENUE MODELS

PART III: ENTERPRISE MOBILITY

MOBILITY IN RETAIL

MOBILITY IN FIELD SERVICE, TRANSPORTATION AND LOGISTICS

MOBILITY IN HEALTHCARE

MOBILITY IN INSURANCE, BANKING AND FINANCIAL SERVICES

MOBILITY IN HOSPITALITY , TRAVEL AND TOURISM

PART IV: MOBILE TECHNOLOGY

MOBILE TELEPHONY CONCEPTS

MOBILE OPERATING SY STEMS

TY PES OF MOBILE APPLICATIONS

MOBILE MIDDLEWARE

NON FUNCTIONAL REQUIREMENTS IN MOBILE APPLICATIONS

EPILOGUE: FROM UBIQUITY TO INVISIBILITY

TABLE OF FIGURES

BIBLIOGRAPHY AND SUGGESTIONS FOR FURTHER READING

IMAGE CREDITS AND COPY RIGHTS

CONTENTS

PART I: HISTORY OF THE MOBILE PHONE

On January 9 2007 the world witnessed the first Apple iPhone This was the day Steve Jobs showcased the iPhone at the Macworld Conference in San Francisco, California in what is considered to be one of the most significant product launches of all times Later that year – June 29 to be precise – people in the United States got their hands on their first ever iPhone Within three months Apple had sold its one millionth iPhone in the US

At one point during this sales blitzkrieg, 270,000 iPhones were sold in a 30 hour time span; an average of 150 iPhones getting sold every 60 seconds!

Since its launch in June 2007 Apple has sold more than half a billion iPhones Seldom hassomething so expensive that occupies such a small volume sold so many units

The iPhone, followed by the Google Android Phone that was launched in 2008 havetogether changed the way we use our phones in such a fundamental manner that wewould be excused in believing that these two devices have changed mobile phone history

in ways that nothing else has

However the roots of mobile technology penetrate much deeper into the annals ofhistory

Over the past six decades, government bodies, international standards bodies, giant

corporations and individual innovators have each pushed the envelope on what is

possible in mobile technology Innovations have come out of university labs, corporate labs, government labs, workshops & conferences, and from people’s homes and garages This evolution has been a tight interplay between the evolution of mobile networks andthe mobile phones that use them Our mobile phones have evolved to meet our evergrowing expectations of them, and the networks have evolved to support what peoplewant to be able to do with their phones

While the evolution of mobile technology has been complex and multifarious, if you stepback a bit from all the complexity, you can spot some pretty remarkable trends andmilestones These milestones have fundamentally shaped the evolutionary history of themobile phone and the mobile network

In the first part of this book, I shall take you through what I hope will be a fascinatingtour of the history of mobile telephony In doing so, we will uncover some astoundinggems of creativity and innovation To borrow a phrase from Steve Jobs we will seek to

"connect the dots" on the path that has led to the creation of the modern smart phone.

So let’s roll the tape back – all the way to the 1800s!

FROM SMOKE SIGNALS TO WIRELESS RADIO

The history of wireless communication goes as far back as we can look into modernhuman history For thousands of years people have been inventing ways ofcommunicating over long distances using all kinds of techniques ranging from fireworks

to carrier pigeons! The early forms of wireless telegraphic systems actually did use thingssuch as fireworks, and smoke or light signals to transmit information in the form of astring of encoded symbols All of this off course looks hopelessly primitive compared towhat the smart phone sitting in our pockets can do today But as you will soon see, theDNA of that very phone were manufactured in this early era

The Photophone

A fascinating invention in the early days of wireless telephony was the Photophonecreated by Alexander Graham Bell and his assistant Charles Sumner Tainter in February1880

Figure 1: Technical Drawing of the Photophone appearing in Alexander Graham Bell and Sumner Tainter’s USA patent 235496 titled “Photo phone-transmitter” published on 14 December 1880.

The Photophone was remarkably elegant in its simplicity

A beam of light was focused into a parabolic mirror which reflected the light right out.One spoke into the back side of such a mirror The mirror flexed back and forth ever soslightly in response to the varying pressure of the sound waves hitting it on its back side.This flexing of the mirror’s surface caused the light that was being reflected by the mirror

to be proportionately modulated, i.e its frequency was altered in proportion to theamount and frequency of the flexing of its surface Thus the light waves that werereflected out from the mirror effectively encoded the speech of the person who wasspeaking into the backside of the mirror!

The receiver consisted of another parabolic mirror which focused the received light wavesinto a special material known as transducer which converted light back into sound.Alexander Graham Bell used Lampblack as the trans-ducting material in his originaldesign

Figure 2: Left: Alexander Graham Bell (1847-1922) Right: Charles Sumner Tainter (1854-1940)

Bell was enormously proud of the Photophone, proclaiming it to be his greatest invention,and also wanting to name his second daughter “Photophone”! Mrs Bell is said to havewisely discouraged her husband from taking this step

Bell’s Photophone was subsequently enhanced by himself as well as several otheradopters of the device in many important ways The direct sound-to-light coupling of theoriginal device was changed into a sound-to-electrical-to-light coupling The range of thePhotophone was increased to several miles The light source was changed from sunlight

to a variety of artificial light sources including infrared light The Photophone was alsoadopted in battlefields during the 1930s and 1940s for communicating between battlefieldfield units A very useful advantage that the Photophone enjoyed in the battlefield wasthat its light based transmission mechanism could not be easily eavesdropped upon

By the turn of the 19th century the advent of radio telegraphy and radio telephony, with

their much longer range and the high degrees of reliability they offered under adverseweather conditions proved to be the beginning of the end for the Photophone as apractical wireless communication system.

The Photophone proved to be a lens into the future of communication in a number ofways For example, the principles of sound-to-electricity-to-light and vice-versaconversion used by the Photophone were astoundingly similar to the fiber-optic basedcommunication systems that came into use almost a century after the Photophone’sinvention in 1880

The advent of radio communication

While Alexander Bell’s Photophone in the 1880s provided a magnificent portal into thefuture of optical communication, a revolution of an entirely different kind was brewing inEurope and in the United States in the area of radio frequency communications

Radio waves are the portion of the electromagnetic spectrum between 3 Kilo Hertz and

300 Giga Hertz The corresponding wavelengths range from 100 Kilometers down to 1millimeter Their use as the medium for sending telegraphic messages proved to be asignificant up-shift in what was possible in the field of long distance wirelesscommunication

In fact the genesis of radio as a method of communication goes all the way back to theearly 1800s

From the early 1800s through the 1860s several scientists in Europe, Russia and the USAdevised experiments which demonstrated the various ways in which electricity andmagnetism were connected to each other Out of this experimentation was born much ofthe path breaking work on electromagnetic theory that would go on to form the basis forall forms of modern radio communications including the cell phones that we use todayand the wireless networks that they operate over Some of the early pioneers in the field

of electromagnetic theory during the 1800s were Hans Christian Ørsted, André-MarieAmpère, Peter Barlow, Johann Salomo Christoph Schweigger, William Sturgeon,Francesco Zantedeschi, Michael Faraday, Heinrich Lenz and Joseph Henry

Much of this work on electromagnetism culminated in the ground breaking publication in

1865 titled “A Dynamical Theory of the Electromagnetic Field” by a 34 year old Scottish

physicist by the name James Clerk Maxwell In his paper, Maxwell presented a grandunification of several properties of electricity, magnetism and light.

Figure 3: Left: Plaque showing Maxwell’s Equations affixed to the statue of Maxwell in Edinburgh,

Scotland Right: James Clerk Maxwell (1831-1879)

Among other things, Maxwell’s theory predicted that electromagnetic waves can travelthrough space at the speed of light

This crucial discovery has been the bed-rock of the field of mobile communications eversince

Figure 4: The Electromagnetic Frequency Spectrum The Y-axis shows frequency in Kilo Hertz on a logarithmic scale (powers of 10) The colored vertical bars indicate the frequency range for various radio frequency phenomena such as short wave radio, MW Radio, FM Radio, the frequency range that the zero-

G networks (MTS, and IMTS) of the 1940s and 50s used to operate in, the frequency spectrum that

modern day cellular phone networks occupy and so on.

In the years following Maxwell’s death in 1879, a brilliant German physicist by the nameHeinrich Rudolf Hertz performed experiments that proved beyond any doubt Maxwell’sassertion that electromagnetic waves can actually travel through space In doing so, the

28 year old physics professor at the University of Karlsruhe, Germany also created amethod to intentionally transmit and receive radio waves in the Ultra High Frequency

(UHF) range.

This would be the world’s first deliberately performed radio-frequency transmission andreception!

Figure 5: Left: Heinrich Rudolf Hertz (1857-1894), Right: Line drawing of the apparatus used by Hertz

for transmitting and receiving radio signals through air.

Unfortunately Professor Hertz, in whose honor the unit of frequency, Cycles Per Sec a.k.a.Hertz is named, utterly failed to realize the sheer importance of his achievement Whenasked by one of his students what use could be made of his discovery he replied,

“It's of no use whatsoever This is just an experiment that proves Maestro Maxwell wasright—we just have these mysterious electromagnetic waves that we cannot see with thenaked eye But they are there."

When the same student persisted by asking what else could be achieved from thisdiscovery, Hertz replied,

"Nothing, I guess."

Nothing could have been further from the truth

The birth of radio telephony

As other scientists around the world came to hear about Hertz’s experiments they sought

to replicate them and to perform their own experiments in the deliberate transmissionand reception of electromagnetic signals

From 1890-1895, scientists such as Édouard Branly, Nikola Tesla, Roberto Landell deMoura, Oliver Lodge, Thomas Edison and Jagdish Chandra Bose built upon the work ofHertz and furthered the field of wireless radio communication In doing so several amongthem demonstrated some of the first experimental telegraphic systems operating in radio

Figure 6: Graphic from Thomas Edison’s 1891 United States patent application # 465,971 illustrating a

means to do radio frequency communication between ships and between ship and shore.

However, in spite of the several patents that were granted in this field, nobody had yetmanaged to create a commercially viable radio frequency telegraph system

That task was to lie with a dynamic Italian engineer and inventor named GuglielmoMarconi

Figure 7: Guglielmo Marconi (1874-1937)

Marconi was able to successfully build upon the work of others before him to create apractically workable and a commercially viable method of radio transmission andreception Marconi obtained a British patent for his invention in 1897, his first of over 35patents which he received in the field of radio transmission The same year the MarconiCompany was established Marconi soon set up the first radio station at Niton, Isle ofWight, England and successfully transmitted a radio message to Bournemouth, Englandover a distance of 22 Kilometers Later that year wireless radio telegraph signals weresent over a distance of 34 miles from Salisbury Plain to Bath, England using Marconi’sradio telegraph technology In the following decade wireless telegraph stations popped upall across the landscapes of Britain and the United States During the early 1900s theMarconi Company also succeeded in commercializing wireless transmissions across theAtlantic and from ship to shore.

Figure 8: Radio transmission (red arrow) by Marconi in 1898 from his first permanent station on the Isle

of Wight, England to Bournemouth, England over a distance of 22 Kilometers.

Figure 9: Marconi’s first transatlantic radio transmission in 1901 from Poldhu, England to St John’s in

Newfoundland, Canada

Figure 10: A schematic of spark gap based radio frequency transmitter of the kind used by Marconi to

perform telegraphic transmissions.

Figure 11: Photograph of an actual spark gap based radio frequency transmitter used by Marconi to make

long distance telegraphic transmissions in the late 1890s and early 1900s.

By 1920s wireless telegraphy had become a global system of communication In manyplaces it replaced the physical cable based telegraph lines that were in widespread use atthat time Radio frequency wireless telegraphy became especially invaluable for ship – to– ship and ship – to – shore communications; an area where cable based telegraphicsystems could not be used

While radio frequency telegraphy was gaining widespread acceptance by the early 1900s,the transmission of sound over a radio frequency channel wasn’t far behind.

The credit for the first sound transmission over a radio channel is said to lie with theCanadian inventor Reginald Aubrey Fessenden

Figure 12: Reginald Aubrey Fessenden (1866-1932)

Fessenden believed that the future of radio lay not in the on-off nature of the sparktransmitters that Marconi’s telegraphy systems used, but instead in a more continuouswave kind of transmission To achieve that, Fessenden used a modified version of thespark transmitter known as the rotary transmitter which produced a more continuousradio signal that was necessary for the transmission of sound

Figure 13: Top: Photo of the rotary gap transmitter used by Fessenden at the Brant Rock transmitting station, Brant Rock, Massachusetts, USA (c1906) Bottom: Photograph of the Brant Rock station in 1912,

taken from Blue Fish Rock The tall stacks exiting from the building's roof are for the steam engine's

boiler.

On December 23 1900 Fessenden successfully made the first long range audiotransmission over radio frequencies over a distance of 1 mile from Cobb island in thePotomac River in Maryland, USA

Fessenden spoke the following words over the radio channel to his associate at the endother:

"One - two - three - four, is it snowing where you are Mr Thiessen? If it is, would youtelegraph back to me?"

His associate replied in the affirmative and the rest is history!

The age of radio telephony was born

During the early part of 1900s Fessenden’s system was extended, modified andaugmented through his work and the work of several others in the field The operating

frequencies were increased The methods of transmission and reception underwentsignificant changes from Fessenden’s original spark transmitter based design Thetransmission range went up from dozens of miles to hundreds of miles and the reliability

of the equipment improved significantly Radio telephony began to be used not just forspecialized uses such as by the US Weather Bureau to communicate weather data amongtheir weather stations, but also for the public broadcast of signals

Up through the 1940s radio telephony proliferated in Europe and North America It wasused for Ship – to – Ship and Ship – to – Shore communications, on the battlefields inthe form of “portable” trans-receiver sets (or walkie-talkies as they came to be called) and

on trains for placing ”pay phone calls” within a certain radial range Some of the earlyexperiments in train based telephones were carried out in 1918 by the German NationalRailway, the Deutsche Reichsbahn By 1926 Deutsche Reichsbahn had installed “pay-phones” in the first class compartments of trains on the Berlin to Hamburg route

In the early years of the 1900s the use of radio frequency based voice communicationproliferated in many parts of Europe and North America However it hardly resembledwhat might pass for a modern telephone system For example, except in a very smallhighly specialized set of cases, you could not simply place a call by dialing somebody’stelephone number Besides the radio sets were anything but portable Each telephone setweighed several dozen Kilograms!

It wasn’t until the 1940s that mobile telephony advanced from these early uses of radiofrequency transmission to something resembling the modern mobile telephone system

FROM TRAINS, SHIPS AND TANKS TO THE MOTOR CAR – THE

ERA OF ZERO-G

The first large scale rollout of a metropolitan mobile telephone network took place duringthe mid to late 1940s Amazingly, the rollout completely skipped the hands and pockets ofpeople and went straight on to get installed in people’s motor vehicles in the form of theCar Phone

There are a couple of important reasons why the first mobile phone roll out in the UnitedStates during the 1940s was also the first car phone rollout of the world For starters each

“mobile” phone unit weighed around 80 pounds (36 Kilograms) It was hardly the kind ofdevice that you could lug around on the street The mobile phone of the 1940s needed thepulling power of your car’s internal combustion engine to move itself around!

Secondly, the mobile phone system of the 1940s was targeted towards an Americanpopulation that was becoming increasingly dependent on automobiles as their primarymode of transport rather than trains What better place to put a phone in than in theircar!

This system in the United States was called by the rather uninspiring name “MobileTelephone Service” or MTS for short

MTS & IMTS

MTS was rolled out by AT & T Bell Laboratories AT & T was already the principal operator

of the Public Switched Telephone Network a.k.a the land based telephone system in theUSA at that time The telephone equipment was designed by Bell Labs but initiallysupplied by Western Electric Corporation and later by General Electric and Motorola

Figure 14: One of the earliest attempts of using a car mounted phone Notice the transmitter-receiver unit and the enormous antenna mounted on top of it This picture was taken circa 1924, four decades before

the rollout of the first commercial car phone network in the United States.

In radio communications, the length of the antenna is inversely proportional to thetransmission frequency You need a long antenna for transmitting or receiving lowfrequency (long wavelength) signals The MTS system operated in the Very HighFrequency a.k.a VHF range (30-300 Mega Hertz) In comparison modern cell phonenetworks operate in the 850 MHz to 2100 MHz Ultra High Frequency a.k.a UHF range.UHF frequencies are anywhere from 3 to 70 times higher than VHF frequencies This inturn leads to a short stubby antenna design like the one found on some of the modern cellphones In fact these days, engineers have found a way to pretty much embed the entireantenna inside the cell phone unit thereby making it completely invisible to the user Onthe other hand, since the MTS system of the 1940s used VHF, one needed to mount aridiculously long antenna on top of your vehicle to get any kind of reception on your carphone in the MTS network On the plus side the use of VHF meant that MTS requiredlower power to transmit and it operated over longer distances Both characteristics weredesirable at the time The whole concept of radio telephony during the better part of the

20th century was based upon the notion of one base station serving a very largegeographical area situated around it The concept of cellular networks, in which mobiletowers located inside small “cells”, would seamlessly hand off calls to towers inneighboring cells as you moved around, had yet to become a practical reality until muchlater in the century

Figure 15: ‘Zero-G’ mobile phone systems such as AT&T’s Mobile Telephone Service were based on the

concept of one large tower serving a large geographical area around it.

Bell Labs designed MTS to operate in two modes – a highway mode and an urban mode.The urban mobile car phone network in America went live on June 17, 1946 when a truckdriver in St Louis, Missouri made the first telephone call from his truck The highwaymode went live shortly thereafter in August of the same year

The MTS system required operator assistance to make any out-bound call from yourvehicle Moreover the system was strictly half-duplex i.e basically similar to a walkie-talkie This meant that you needed to push a button on the handset to talk and then let go

to listen The phone equipment mounted inside the vehicle consisted of a receiver unit (also known as a transceiver), which took up most of the trunk space of yourvehicle, a large antenna that would be mounted on the roof and a handset that wasmounted just underneath the dashboard The entire equipment drew power from the car’sbattery The MTS car phone also had a very curious feature called a call decoder The calldecoder sat inside the trunk of the vehicle as part of the rest of the trunk mounted unit.Each time someone called into the base station so as to try to reach a specific car phoneuser, a wheel fitted inside this call decoder would mechanically click in response to theelectrical pulses sent out by the base station Interestingly, this clicking happened inside

transmitter-the decoder of every single vehicle lying within transmitter-the base station’s range! So when you

heard the trunk of your vehicle start clicking, you knew that someone was trying to reachsomeone else around you on the MTS network However, exactly one of these decoders –the one whose phone number matched the one that the base station operator was trying

to reach – would click all the way through and that would trigger the call ringer insideonly that vehicle!

Figure 16: The illustration shows how the MTS and IMTS car phone equipment that AT&T supplied to its

customers during 1940s-70s, was laid out inside the customer’s vehicle.

The MTS equipment was heavy, power hungry and came with very few channels – whichmeant that only a few people could call at one time within a base station’s network And itwas also very expensive Still, MTS proved to be dramatically popular within NorthAmerica The initial rollout itself covered 60 cities in the USA in its urban mode and 85cities in its highway mode The system handled more than 4000 mobile subscribers and117,000 calls a month The waiting lists grew longer by the day

During 1940s, 1950s and into the early 1960s MTS was improved upon iteratively.Miniaturization was implemented and the telephone equipment in the vehicle becameless bulky The system began to support full duplex operation, i.e the person could talkand listen at the same time In some cases the person could also directly dial the numberfrom their car phone instead of going through operator assistance The direct dial featurewas seen to be a tremendous advancement at the time

Figure 17: Motorola TLD 1100 MTS Car Phone (1964) Source: National Electronics Museum, Maryland,

USA

In 1964, this later feature of direct i.e non-operator assisted dialing from your car phonewas mainstreamed by the next generation of MTS AT&T once again rather un-imaginatively named the improved version of the Mobile Telephone Service as theImproved Mobile Telephone Service a.k.a IMTS

From 1964 through the early 1980s, IMTS flourished in North America Full duplex directdialing from the car phone became a reality for most North American car phone users.During this time, the invention of the electronic solid state transistor also enormouslyhelped the cause of mobile telephony As a result phone units were further miniaturizedand by early 1970s, Motorola was already manufacturing completely solid state versions

of phone units

During the 1960s another car phone based mobile telephone service called the RadioCommon Carrier (RCC) was introduced in the United States by companies that competedwith AT & T’s MTS and IMTS based car phone systems RCC continued to operate up untilthe 1980s

All through the 1940s to 1980s, MTS, RCC and the IMTS compliant mobile phones werestill too bulky to leave the vehicles that they were mounted in A possible exception wasthe introduction of “attaché-phones” in the late 1960s These units were IMTS compliantmobile phones which were small enough to fit inside a stylish brief case that you couldcarry around with you It would make quite a picture to be seen carrying around such abriefcase sized mobile phone today In the late 1960s it was the state of the art for mobile

telephony, and a fashionable thing to be seen lugging around one of these ‘attachéphones’.

Figure 18: The Trigild Gemini 2 briefcase phone

The growth of zero-G systems outside North America

During the 1940s through the 1980s, while the USA and Canada were going all out intheir roll outs of car phones, the rest of the world wasn’t far behind

The A-Netz mobile telephone network that was launched in West Germany in 1958quickly became one of the world’s largest mobile phone networks of that time A-Netzwas superseded by the B-Netz network in 1972 which among other things offered directdialing in place of operator assisted dialing

In 1950s, the USSR began the development of the Altai mobile car phone service Theservice was first introduced in Moscow in 1963 and soon spread to major metropolitanareas of the USSR

Finland launched the ARP car radio phone service in 1971 and by 1978 it had covered100% of that country Norway launched its first public mobile telephone network calledOLT in 1966

One of the largest zero-generation analog mobile telephone network rollouts happened inSweden during the 1950s through the 80s, when the country launched the MTA, MTB andMTD mobile telephone networks At its peak, MTD had over 20000 mobile phonesubscribers and over 700 phone operators switching calls between users

The Nordic countries would continue to remain at the forefront of mobile telephony in

the decades to come.

Drawbacks of the earlier mobile networks

All of the mobile telephony systems described in this chapter, irrespective of the countrythat they operated in, were hobbled by several common drawbacks They operated mostly

in the VHF range and rarely in the UHF range This meant long antennae on mobile units.The long range of VHF signals as compared to UHF used by cellular networks, meant thatVHF frequencies could not be reused by base stations in adjacent areas, due to excessivesignal interference Therefore the available VHF spectrum could accommodate only asmall number of phone subscribers Network congestion happened quickly, and often.The mobile telephone equipment weighed several dozen kilograms and literally required

a motor vehicle to be carried around The transmission was done via analog signals andtherefore was very easy to be eavesdropped upon Furthermore, the whole system worked

on the concept of central base stations serving geographical areas around them Thereforecoverage was basically on a line-of-sight basis This meant that if you went behind a tallbuilding, a hill or any other large object you immediately lost the signal Furthermore, thelong wavelength VHF signals don’t get reflected very well back to earth by the earth’satmosphere Due to the earth’s curvature, you could lose the signal even on absolutelyobstruction-less ground when you travelled “over the horizon” with respect to your basestation These early mobile phone systems could not, and did not, scale well to largegeographies The concept of roaming, although existent at the time, rarely workedseamlessly for the user

The advent of cellular telephony in the 1980s, along with further miniaturization of themobile telephone equipment began to finally address many of these constraints Mobilephones started freeing themselves of the motor vehicles that they used to be trapped in.The 1980s saw the concept of the mobile pocket-phone truly become a reality

FROM THE CAR TO THE STREETS AND INTO THE SHIRT POCKET

a phone call is in progress

Figure 19: The black hexagons in the graphic represent the geographical cells of a cellular network Each cell contains a mobile tower at the center of the cell (towers T1, T2, T3, T4 in the illustration) Each tower transmits into its cell using three different frequencies in three different directions that are 120 degrees apart (shown by the blue double headed arrows) The actual cell in the cellular network is therefore the red colored hexagons in the graphic Each of these red colored cells is divided into three regions (R1, R2,

R3) Each cell tower services one region within a red cell When the mobile phone M1 shown in the graphic is switched on, it will scan for signals from all neighboring towers Since it lies in region R1 it will

in theory find the strongest signal coming from tower T1 and begin communicating with it.

A cellular phone network enjoys several important advantages over the “zero-G” spoke networks described in the previous chapter Since each cell covers a geographicallysmall area, much less power is needed to transmit and receive signals This makes the cellphone batteries smaller and less heavy This in turn reduces the overall size and weight ofthe mobile phone Cellular networks also operate in the Ultra High Frequency (UHF)band leading to short stubby antenna designs on the phones instead of the out-sizedantennae that were needed by the Very High Frequency (VHF) based car phone systems

hub-and-of the 1940s, 50s and 60s The cellular nature hub-and-of the network also means that the

“over-the-horizon” issue faced by the zero-G networks is very elegantly avoided A cellularnetwork can scale virtually infinitely over and across mountains, around tall buildings,and across rivers and lakes simply by adding more cells to the network Finally, and veryimportantly, on a cellular network two subscribers can talk on the same frequency band

as long as they are in different cells This enormously increases the number ofsimultaneous conversations that the network can support, and thereby addresses thenetwork congestion problem that plagued the hub-and-spoke based zero-G networks

Birth of cellular telephony concepts

The genesis of cellular telephony began as early as 1940s in Bell Labs, USA However,cellular networking concepts continued to be researched upon all the way through to late1970s, i.e in parallel with the large scale roll outs of zero-G networks that were happeningworld wide as described in the previous chapter

On 11 December 1947, Bell Labs researcher Douglas H Ring together with his colleague

W Rae Young dispatched an internal Bell Labs technical memo that introduced theconcept of utilizing adjacently located cellular coverage areas so as to increase thecoverage of the mobile telephone service across the nation While the memo was detailedenough in the description of how the cellular network would function in theory, thetechnology to actually make it work did not exist at the time Neither had the FederalCommunications Commission (FCC) in the United States opened out the frequencychannels that such a cellular system would need Given this situation, the field of cellulartelephony would languish for another 20 years Meanwhile, AT & T continued to petitionthe FCC for additional frequency allocations Researchers at Bell Labs and Motorola aswell as ones outside the United States would also continue to make progress in cellulartelephony research

Figure 20: The concept of the cellular network described by Bell Labs researcher Douglas H Ring in his

1947 memo to Bell Labs was remarkably similar to the structure of modern cellular phone systems The concept described in D H Ring’s memo involved an area that was to be served by a large number of radio

stations using ‘n’ different frequencies The service radius of each station is fixed The stations are arranged in such a manner that each station is surrounded by 6 other equidistant stations.

In the 1960s another set of Bell Labs researchers, Richard H Frenkiel, Joel S Engel andPhilip Thomas Porter built upon the work of Ring and Young and gave it the full technicalrigor that would later form the basis for AT & T’s first commercially deployed cellularphone service in America called the Advanced Mobile Phone System (AMPS)

Field trials for AMPS began in 1978 in Chicago, Illinois and Newark, New Jersey AMPSwas launched as the United States’ first cellular mobile telephone service in Chicago, IL in

1983 AMPS was operated by the Ameritech Corporation

World’s first hand held cell phone

Motorola was a major equipment supplier to AT & T for the MTS and IMTS car phonesystems during the 1940s through the 1980s During this time the company becamedeeply entrenched in the field of mobile telephony and particularly in the manufacturing

of state-of-the-art telephone handsets

Figure 21: Left: Motorola car phone dialer unit (c1960) Right: Car phone dialer unit mounted under the

dashboard of a 1968 Cadillac Fleetwood Brougham.

During the 1960s, while Frenkiel, Engel and others at Bell Labs continued their work onthe development of cellular phone networks, Motorola invested in the development ofcell phones that would be hand held and truly portable This feat had started becoming areality due to factors such as the advent of solid state electronics The solid state deviceversions of the mobile phones were lighter and less power hungry than their vacuum tubeand mechanical relay based cousins They also required a smaller, lighter battery Overallthe phone could be made smaller and lighter than the briefcase sized and car trunk sizeunits that were manufactured in the 1940s and 50s

Motorola’s efforts at producing a portable cell phone reached fruition in 1973 when Dr

Martin Cooper who headed Motorola’s communication systems division created theMotorola DynaTAC portable cell phone.

Figure 22: The Motorola DynaTAC8000x cell phone

The original DynaTAC created by Cooper and his team was more than 10 inches long andweighed almost 2 pounds Most of the weight of the phone came from its battery It had atalk time of 20 minutes after which it needed to be charged for 10 hours Cooper has sincequipped that the talk time was never an issue since you couldn’t actually hold the phone

to your ear for 20 minutes straight due to its sheer weight!

On April 3 1973, Motorola gave a famous street demonstration of the DynaTAC phonewhen Cooper and his manager John F Mitchell demonstrated the phone to the media inmid-town Manhattan Cooper went on to dial Dr Joel Engel at Bell Labs and spoke thefirst words on the world’s first truly portable cell phone:

“Joel, this is Marty I'm calling you from a cell phone, but a real cell phone, a handheld,personal, portable cell phone”

Unfortunately the size and weight of the DynaTAC quickly earned it the nickname “thebrick”

Over the next 10 years Motorola invested heavily in the development of the “brick phone”and the first commercial version was launched in 1984 It was called as the DynaTAC8000X and it cost USD 3,995 It was available for use on the AMPS cellular networkwhich was launched in the US just a year earlier

The 8000x was somewhat smaller and lighter than the “brick”

The growth of cellular telephony outside the United States

The USA rolled out its 1G cellular network in the 1980s, but this time they were beaten tothe line by Japan and the Nordic countries

The world’s first fully automated cellular network was launched not in the USA, but inJapan in 1979 by Nippon Telephone and Telegraph (NTT) It operated over the 400 and

800 MHz ranges The network was launched initially in metropolitan Tokyo Within thenext five years it spread all across Japan making it one of the first countries of the worldwith 100% 1G cellular coverage

Two years later in 1981, the fully automated Nordic Mobile Telephony (NMT) cellularnetwork was launched in Sweden and Norway, followed by a launch in Denmark andFinland in 1982 and Iceland in 1986 Interestingly the first commercial service of NMTwas started in Saudi Arabia in 1981 even before the network began operation in Sweden.The initial “user equipment” a.k.a the phone used on NMT continued to be the heavy carphone based system However NMT’s specifications were open and therefore encouragedwidespread competition among mobile phone manufacturers This raised the fortunes ofcompanies such as Nokia (called Mobira at that time) and Ericsson in Europe, and furtherenhanced the global reach of established players such as Motorola A wonderful featurethat NMT came with was the ability to roam freely on it across all the Nordic states thatimplemented it

During the 1980s, NMT spread into several Eastern European Countries and Russia.During the same period AMPS spread its wings across North America, and its variants –the TACS (Total Access Communication System), JTACS (Japanese Total AccessCommunication System) and ETACS (Extended Total Access Communication System) –spread into the United Kingdom, Ireland and Japan

The 1G analog based cellular networks of the 1980s such as AMPS, NMT, TACS, JTACSand ETACS were a significant improvement over their non-cellular 0G cousins who hadprevailed from 1940s to 1970s

1G mobile phones

The 1G mobile phones of the 1980s started out as large, bulky and power hungry As thedecade wore on, the phones shrunk in size, weight and power consumption

The 1980s had begun with the famous introduction in 1984 of the Motorola DynaTACdescribed earlier However, there were a few other noteworthy examples of 1G cell phonesduring the 1980s that have shaped the field of cell phone design and cell phone capabilitythrough the 1980s and into early 1990s.

Consider just some of the following phones introduced by Nokia around this time andone gets a feel for how fast mobile phone technology was developing during the 80s

In 1982 Nokia introduced its first 1G cellular car phone: the Nokia Mobira Senator 450 Itoperated over the 450 MHz NMT network and weighed a whopping 10 Kilograms

Figure 23: Nokia Mobira portable cellular phones of the 1980s

1984 through 1989 saw the introduction of the Nokia Mobira Talkman series phones such

as the Talkman 320F, 450, and 900 The Talkmans weighed in just under ½ a kg TheTalkman was considered to be quite portable by 1980s standards

The Nokia Cityman Series was manufactured from 1987 to 1990 This series saw theintroduction of five Cityman Series phones from Nokia – the Cityman 1320, 900, 150, 190and 100

Figure 24: (Left) Nokia Cityman 100 ETACS version announced in January 1990, (Right) Cityman 150 announced in 1989 The Nokia 1100 launched in 2003 is also shown at extreme right for comparison.

The 1987 Cityman 1320 was a direct competitor to the Motorola DynaTAC introduced in

1984 The Cityman 1320 was also Nokia’s first truly hand held phone Soon after itslaunch the Cityman 1320 received a huge publicity boost when it was used by MikhailGorbachev to make a public phone call from Helsinki, Finland to his communicationsminister in Moscow That soon earned the phone the nickname “Gorba”

Figure 25: Nokia Cityman 1320 (Left) and Motorola DynaTAC 8000X (Right)

The Cityman series brought with it a huge reduction in the size of the device and adramatic increase in the yuppiness of design The weight of the device unfortunatelyremained pretty much in the same league as the Talkmans The Cityman 1320 weighed in

at 3/4th of a kilogram and the Cityman 100 weighed in at just under ½ KG.

Two more mobile phones produced during the 1980s deserve a special mention

The Technophone

In 1984 Nils Mårtensson, a Swedish radio engineer left Ericsson to set up his owncompany called Technophone His goal was to create the smallest, lightest and the mostuser friendly cell phone of the time The Technophone company sold its phone throughanother outfit called Excell Communications With the launch of the Technophone ExcellM1 cell phone, Mårtensson succeeded in his goal

The M1 was by far the world’s smallest and sleekest mobile phone While its competitorswere still struggling to breach the ½ KG mark, the M1’s weight came in well under 350grams

And for the first time a cell phone fitted neatly inside your shirt pocket!

Figure 26: Technophone PC107/3

Technophone went on to become hugely successful, selling thousands of phones a month

By 1991 Technophone had become Europe's second largest mobile phone manufacturerwith a turnover of £49 million By comparison Nokia was Europe's largest mobile phonemanufacturer at the time with a turnover of £330 million Later that year Nils

Martensson sold Technophone to Nokia for £34 million.

This single acquisition helped propel Nokia to the world number two slot just behindMotorola

The Motorola MicroTAC

The second significant mention of the late 1980s cell phone era was the MotorolaMicroTAC Introduced in 1989, the MicroTAC was Motorola’s clearest response yet to thedramatically shrinking cell phone sizes and brought with it an element of sheer style thathad been displayed by its competitors’ products

The Motorola MicroTAC was the world’s first flip top phone

Figure 27: Motorola MicroTAC 9800x

The extent to which Motorola likely wanted to introduce an element of style into theMicroTAC’s design is evident from the fact that the flip panel of the phone wascompletely cosmetic The panel did not carry a microphone at all! What’s more, theexternal aerial of the phone was also a fake! The phone had an internal aerial but marketresearch at the time apparently pointed to people wanting their phone to sport an externalantenna

The Technophone in 1986 and the Motorola MicroTAC three years later set the high barfor the mobile phone industry in the years to come

It wasn’t until the introduction of iconic mobile devices such as the IBM Simon or theNokia Communicator in the 1990s that the mobile phone industry took the next leap intowhat a cellular phone could achieve

FROM ANALOG TO DIGITAL – 2G AND BEYOND

During the 1980s, the introduction of cellular phone networks had revolutionized mobiletelephony in ways that could not have been achieved in the four decades before theirintroduction However a common characteristic of the 1-G cellular systems of the 1980swas that they used analog signals to carry the information between the cell phones andthe cell phone towers

Second generation (2G) cellular networks were introduced in the early 1990s These 2Gnetworks digitized the communication between the cell phone and the tower This singlechange from analog to digital yielded enormous benefits To begin with, digitaltransmission could be heavily compressed by the phone before transmission Thisdramatically reduced the bandwidth requirement for each phone call Thus each cell ofthe cellular network could support many more simultaneous conversations than before.Secondly, the digital signal could be very easily encrypted thereby making eavesdroppingmuch harder to do than with the 1G analog signal Digital transmission also consumedless power, thereby further reducing the size and weight of the batteries that were used bythe phones And with digital, there was also no line noise or ‘hum’ during pauses in theconversation

Finally, and arguably most significantly, digital transmission made it possible to transmitdata over a wireless channel along with voice

Radio telegraphy began in the 1890s as a way to transmit data symbols over a wirelesscommunication link Once hundred years later, the introduction 2G networks in the early1990s, with their ability to transmit data wirelessly, curiously brought the field of radiocommunications full circle!

In yet another sense, digital telephony technology and the 2G, 3G and 4G networks that ithas given rise to have also given birth to a whole new kind of internet – a wirelessinternet!

The evolution of digital telephony

Several interesting events have shaped the evolution of digital telephony

Up through the 1990s, there were three primary crucibles of mobile technology evolution:

The United States, Europe and Japan Each one took an extraordinarily different route formigrating from 1G to 2G.

The United States made some early successful attempts in the late 1980s to create adigital version of the 1G AMPS cellular system which was already in widespread use inNorth America around that time From this resulted two offshoots - the Motoroladesigned Narrow Band AMPS or N-AMPS and the more widely deployed Digital AMPS orD-AMPS

D-AMPS which was first launched in the US in 1990, was specifically designed to bebackward compatible with the analog AMPS so that you could use a dual mode(analog/digital) cell phone on both versions of the system

On the other side of the world, Japan migrated its vast analog cellular network operated

by Nippon Telephone and Telegraph (NTT) which was deployed through the 1980s, to adigital variant called PDC (Personal Digital Cellular) The 2G PDC cellular network beganoperation in Japan in 1993

Meanwhile, Europe took an altogether different route for 2G adoption By 1990, theEuropean Union had a wide variety of analog cellular networks proliferating throughoutits jurisdiction For example, there were at least half a dozen country specific variants ofthe NMT cellular network operating within the member states of the EU The UnitedKingdom and Ireland on the other hand had the TACS and ETACS cellular networks

Paradoxically, this fragmentation of 1G cellular networks among the European states was

to lead to one of the greatest successful unifications of cellular networking standards thatthe world has ever witnessed

The birth of the GSM standard

As early as 1981, European member states recognized the need for networkstandardization and consolidation into a single unified digital cellular network In 1987,thirteen European Union countries signed an MoU in Copenhagen mandating a singledigital cellular communication standard to be implemented across the EU This was to bethe genesis of what would go on to be published as the Global System for Mobilecommunications a.k.a the GSM standard in 1990

The year 1991 saw the world’s first GSM network go online in Finland The network was

built by Telenokia and Siemens and operated by Radiolinja The world’s first GSM callwas made over this network on July 1 1991 by the former Finnish prime minister HarriHolkeri from Helsinki, Finland to the deputy mayor of the city of Tampere The followingyear the world’s first SMS was sent over the GSM network.

On 10 November 1992, the Nokia 1011 (a.k.a the Nokia Mobira Cityman 2000) waslaunched The 1011 quickly went on to become the world’s first mass produced andcommercially successfully GSM phone The Nokia 1011’s shell had the iconic “candy bar”shape – a design that was to be adopted extensively by cell phones in the decades to come.Incidentally the product number 1011 also marks the date that Nokia launched the phone– November 10

Figure 28: Nokia 1011

GSM quickly established itself as the 2G cellular network of choice across Europe GSMcontinued to be adopted worldwide at an astounding rate Today it is estimated that morethan 80% of the mobile phone carrying population of the planet communicates over the

2nd generation (2G) GSM network or an evolved version thereof

Data transmission goes wireless

Figure 29: The above graphic illustrates the explosive growth in data transfer speeds supported by various wireless protocols The X-axis represents time The circles represent various data transfer protocols The area of each circle is proportional to the theoretical download speed supported by that protocol As you can see some circles are too big to fit inside the graphic For such circles, the fraction of

the circle that is visible in the graphic will give you an idea about the size of the overall circle and therefore the data transfer speed supported by the corresponding protocol The color of each circle represents the protocol generation viz, 2G, 3G etc The data speeds of the Bell 101 modem of 1958 and the Hayes Smartmodem introduced in 1981 are also shown so as to provide a sense of perspective about the

phenomenal growth in the data transfer speeds achieved over the past few decades.

Data could be transmitted wirelessly even in the analog 1 G wireless phone networks.However one had to “acoustically couple” i.e literally physically strap a modem to one’smobile phone so that the acoustic signal generated by the modem could be sent over thewireless network via the phone’s speaker, and the return signal could be “heard” by themodem via the phone’s receiver In a way this was no different than acoustically coupling

a modem to a standard landline phone Slightly advanced versions of this technique relied

on building the modem into the mobile phone unit so that one did not have to physicallystrap the modem on to the phone But the principle remained the same Overall it was avery primitive way of transmitting data and one could get speeds of no more than 2400bits/second i.e basically the same as that of the 1984 vintage V.26bis modem

By 1991, GSM based cell phone networks started providing wireless data transmissioncapability directly over the mainly voice based 2G network using a new kind of datatransfer protocol called Circuit Switched Data In CSD, a single TDMA1 (Time DivisionMultiple Access) radio timeslot is dedicated to the transmission of data signals Thiseffectively builds dedicated capacity within the network for carrying data traffic From thenetwork’s perspective, when a user transmits data, the cell phone places a “Data Call”

using CSD over a dedicated wireless data channel between the phone and the base station.With the introduction of CSD in 1991, data could be transferred over the 2G cell phonenetwork at a data transmission rate of around 9600 bits/second (9.6kbps) This mightseem like a tiny speck as compared to the dozens of megabytes that your phone guzzlesper second today when you stream a movie over 3 G or 4 G However even at 9.6 kbps, thefirst circuit switched 2G networks of the early 1990s had taken a giant step towards usingthe same wireless channel for both voice and data traffic – an important evolutionarystep.

During the 1990s, the miniscule data rate of CSD was quickly enhanced via thedevelopment of several efficient data transfer protocols on the base GSM network Fore.g the High Speed Circuit Switched Data (HSCSD) protocol boosted data transfer rates to

Through the early years of the 21th century, mobile data transfer rates have grownsteadily With that, the nature of data that is being transmitted into and out of people’scell phones has also undergone a huge change Over the turn of the 21st century, GPRSwas just about good enough for low bandwidth wireless data exchanges and for accessingwebsite content that was specially optimized for transmission over low bandwidthwireless connections This was the era of the Wireless Access Protocol (WAP) based