Farley (2005): Mobile Telephone History
Summary
Farleys text is a run through the history of mobile telecommunications. As he states, mobile telephones are perhaps the most important communication tool of our lives. Though mobile communications in its current form is rather new, the entire story is at least half a century old but on the way, many different obstacles have occured which required addressing in the co-evolution of the technology. Issues concerning: government regulation, scarce spectrum, hardware limitations, nations individual solutions.
Mobile telephony in the form of radios started their application following WW2. At first as one-way radios used by government institutions, and later (1945) improved to two-way radios(460MHz) and implementing the basic concept of frequency reuse. The ruins left behind WW2 provided an opportunity for some countries to finally address civilian communication in a structured way - at first by implementing conventional landline and services though. The US was however in a rather unique position, with the infrastructure virtually intact, they could continue research in mobile radio. Three major organisations in this were Bell Labs, Motorola and AT&T with the FCC serving the role of the regulator.
In 1947 the first commercial mobile radio/telephone service begins. A co-op between AT&T and Southwestern Bell. Modelled after conventional dispatch radio, the analog system consists of a centrally located antenna providing six channels between 150MHz and 60kHz. However, unexpected interference forced Bell systems to only use three channels.
The concept of a cellular telephone system was first presented and discussed later same year. What defines a cellular radio system is: a network of small geographical areas called cells; a base station transmitter in each cell; cell traffic controlled by central switch; frequency reuse by different cells etc.
In 1949 the FCC on request allocated more frequencies to accommodate already filling calling capacity on current networks. But the half of the new frequencies were given to other companies (Radio Common Carriers = RCC) to create competition. By 1978 these would service 80.000 mobile units, twice of AT&T.
In 1948 Bell Systems unveils the transistor which was later to play an integral part in the evolution.
Outside the US, development was generally slower, but three countries play major role: Finland, Sweden and Japan.
In the late 40s/early 50s, Swedish telecommunications tried and quickly implemented first automatic Mobile Telephone System (MTA) in Stockholm - first handsets are very energy demanding, relying on car batteries. In Japan, Nippon Telephone & Telegraph becomes privatised and research division is strengthened and looks to produce for growing radio/television broadcast markets. They are strongly encouraged along the way by Edwards Deming, to always focus on quality in electronics.
In 1958, Texas, the first Integrated Circuit was created - proving that resistors, capacitors, diodes and transistors can co-exist on a single block of semiconductor.
First update to the analog mobile telephone system in US was done in 1964 and called IMTS - it featured: talk without having to press a button; direct dialing; automatic channel selection; reduced bandwidth between 25-30kHz. In same period, Swedish Telecommunications replaced their MTA system with the improved MTB.
In 1967, Nokia was formed from the two companies Finnish Rubber Works and Finnish Cable Works. They focus research in semi-conductors and develops digital landline telephone switches.
In the late 60s NT&T begins research on a nationwide 900MHz cellular system for Japan - the system has to replace the current, there is no way of evolving the current to cellular - requires new base stations and mobiles.
The scheme for frequency-reuse was submitted by Bell Systems in 1970 but wasnt accepted until 6yrs later due to fear of Bell System monopoly. In 1969 Bell System had already made the first commercial cellular radio system operational, implementing frequency reuse in the 450MHz band in a small zone system.
In 1971 the Nordic Mobile Telephone group started planning a Scandinavian wide mobile telephone network based on analog (they did not feel ready to use Intels first microprocessor introduced a year before). This network, MTD, was estimated to be ready 1980 and was shut down 1987. ~20.000 subscribers required 400 operators.
In the late 70s, the FCC, to provide better service and keep rates low, required Bell Systems to have competition in every cellular market. But it didnt work, prices and service-level remained the same. In 1982 Bell Systems was then divided into seven parts, providing different products and services.
In the mid 80s most of the european countries had their own analog mobile tele communication that do not ?talk? together. This created a presssure to find a solution that unifies mobile communication for all these countries. US, being just one country, did not have same pressure to find a solution - standards like IS-41 ensured calls are possible city to city and state to state.
In 1983, the US launched a new commercial cellular service base on AMPS and Motorolas Dyna-TAC, it became unexpectedly popular - from 340k in 1985 to 1.300k in 1987.
Approximately same time in South Korea another AMPS system was created.
In 1982, twenty-six companies start developing GSM in EU. It was to be non-backwards compatible, patterned after the ISDN standard, operating in the 900MHz band and was to be digital.
In the US they were using TDMA by 1990 which tripled the call capacity by virtue of being digital, but it would soon fill capacity again. A general problem with the time-division type networks is that they are not good for data transmissions, for voice they are fine, similar to the landlines they were modelled after, but as more content became to emerge, a switch to code-division type networks had to be done. The CDMA scheme is approved in 1993, but later in the mid90s, the FCC auctions the 1900MHz band and allows more carriers and channels. Soon after, the first GSM service is rolled out in Washington-Baltimore by Sprint Spectrum.
By 2005 it GSM and CDMA continues to be installed, but no new technologies seem to be rolled out. With the exception of China which decided to implement the hybrid technology TD-SCDMA in order to keep market closed.
Satellite telephone (Iridium) has been attempted in 1998, but was a major disaster: doesnt operate indoor, and costs of equipment is quite high.
Mobile telephony will continue to be an important part of communication technology development.
Comments
The article seems very pro de-regulation and free-market. I am not against that, but think the article seems to keep re-confirming it again and again through the text.
Goggin (2006):?Making Voice Portable: The early history of the cell phone
Summary
Like Farleys text, Goggin summarizes the history of the development of cellular telephony. Goggin starts a little earlier than Farley. In 1794 the first telegraph was created, and half a year later there was approximately 5000km of lines with 354 stations. The telegraph very closely modelled the structure of the railway which also was under expansion. But instead of transporting people and goods, the telegraph transports information via signals, codes and messages. By the end of the 19th century, it had become a global communications network involved in global trade, war, colonialism and imperialism. Following Graham Bells demonstration in 1877, the telephone emerges to replace the telegraph.
In 1885 Bell founds AT&T to defend its patents. By 1910 there were already 10mio telephones in use worldwide (US accounts for 70%). 12 years later the number has doubled. Wireless telegraphy was actually patented in 1896 by Marconi as early as that.
The term ?telecommunications? was not coined until 1932 and at that time, the inventors mostly expected any such device to be/have interest for business in financing, ordering and alarming - all the same roles as the telegraph. The use for ?sociability? was long repressed because social conversations did not fit the understanding of the technology.
In the mid70s, Citizen Band was introduced and grew to become quite popular, though ignored by executives and network managers as something to be taken seriously. It was a band designated to public use, where people with their car-radios can listen and push-to-talk on a kind of party line system. Private conversations are not possible. At its peak, this service had around 50mio users in US.
Pagers
By 1994 there were 61mio pagers. Mostly for business/professional applications, but in Japan, pagers had found a niche among young and teenage women who used these devices extensively for texting.
Analog (1st gen cellular) vs Digital (2nd gen cellular)
Because digital (GSM,CDMA,TDMA) is based on packet switching, lost packages has adverse effects on the reception of the transmission. GSM is designed to reach 30km. Comparatively, the analog cell phones can reach up to 100km because ?data loss? just results in a gradual fade of signal quality and clarity which is not a problem.
Generation 2.5 cellular introduced new features which regards to multimedia and providing the ability to send and receive images, videos and audio. Of which was to turn into its own lucrative market from 1990 to 2003.
Comments
Why is there no mention of Tesla?s experiments in wireless communications? Doesnt he have some value in the development too?
Abrahamson (2003): Hear me now: Competition, regulation and innovation in mobile telephony in the united states 1945-1983
Summary
Abrahamson argues that the core of cellular telephony began as an american idea, but due to regulation and other factors, america didnt keep the edge of the development. A study estimates that the cost of the delay was 86billion in reduced consumer satisfaction and production profits. This case with cellular telephony is often used as an exemplar for the failure of regulation.
Abrahamson shows that the criticism is often evidence of misunderstanding of the complexity of the regulatory system. Points out the role of co-evolutionary processes by which new technologies are developed and come to the market.
This text wishes to cast more light on the interrelations of the different institutions in the development of cellular telephony in US. He identifies four principal actors: AT&T - the most extensive and efficient wireline telecom; FCC - the institution managing public airwaves on behalf of the government; Motorola - the ?merchant? of the radio industry (one-way radios, two-way radios, Civilian Band); RCC - small, specialised service providers for paging and answering services.
Abrahamsons first argument is that innovation is inherently a social process and shaped by public/private institutions, and the societies in which they operate. The process of cellular telephony did not require any scientific breakthroughs - the most crucial topic, frequency reuse, was developed for other industries and adapted to cellular. Managers and regulators held back wireless telephony development, stifling investment and slowing pace of innovation.
Comment
Finland, Japan and Sweden seems, based on the articles, to have had less regulation than US.
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