# Transportation Deployment Casebook/2018/China Mobile phone (1987-2016)
## The Introduction of Mobile Phone

A mobile phone (cell phone), or wireless phones, often called "Big Brothers" in the early days in China, is portable telephone terminals that could be used in a wider range in service area. They were first used by Bell Labs in the United States. The field mobile phone manufactured in 1940 developed. On November 18th, 1987, the first analog cellular mobile phone system was completed and put into commercial use in Guangdong Province.
The essential technological characteristics incorporate the discovery of electromagnetic radiation, the invention of telegraph and landline.
Compared with the landline, the initial advantages of mobile phones have no place restrictions on communication and are faster than telegrams. With the development of mobile phones, more and more functions are given to mobile phones, it can help us improve work efficiency, enhance the feelings of friends and family, and relax such as playing music, watching videos, taking photos, etc.
The current market of mobile phones is extended to everyone and everywhere.

## Before the Birth of Mobile Phone

Back to the scene prior to the advent of the mobile phone in China, the major communication method include letters, landline and city public telephone.
One of the limitations of letters is its low communication efficiency because it usually takes ten days and a half or more to receive letters. In addition, information on the way of letters is easily destroyed or lost, in the event of extreme weather or human error.
Compared to the mobile phone, it is obvious that the limitation of the landline is not convenient enough. When you have a call, you have to be next to the phone and activities are limited. Second, the installation of the phone is relatively more troublesome. The city public phone has the same limitation with the landline, and it is more inconvenient because the location of the telephone is outside your home and the number is limited.
In 1987, in order to tie in with the "6th National Games" held in Guangzhou, the wireless branch of the Guangdong Post and Telecommunications Bureau is preparing to launch the first batch of 100 analog mobile phones. This is the most direct factor to make mobile phones evolve in the market. Besides, the demand of public for more convenient communication and pursuing the latest fashion pushed the new product into the market.

## The Birth Phase of Mobile Phone (1987-1997)
### The invention of mobile phone

In 1831, Faraday discovered the phenomenon of electromagnetic induction in the United Kingdom. Maxwell further elaborated the research results of Faraday et al. using mathematical formulas, and extended the theory of electromagnetic induction to space. After more than 60 years, Hertz confirmed the existence of electromagnetic waves in the experiment. The discovery of electromagnetic waves has become a turning point for "radio communication" from "cable communication" to the origin of the entire mobile communication.In 1908, an American named Nathan Stubfield made the first radiotelephone device in a rural house in Murray, Kentucky. This mobile phone for wireless mobile communications is a human "The earliest exploration of technology.In 1924, the public trial began with a tram connection between Berlin and Hamburg. In 1925, the company Zugtelephonie AG was established to provide train telephone equipment and provided telephone service on the German national railway company's train in 1926. It also provided German mail service on the route between Hamburg and Berlin and was approved. For first-rate travelers. In 1940, Bell Labs of the United States produced a mobile telephone in the field. In 1946, the world made a phone call from a mobile car in St. Louis with a mobile phone.In 1973, a man stood on the streets of New York and pulled out a radio telephone with about two large bricks and started talking. This person is the mobile phone inventor Martin Cooper. At that time he was a Motorola engineering and technical personnel. This was the first mobile phone in the world at the time。In 1975, the United States Federal Communications Commission (FCC) determined the frequency spectrum of land mobile telephone communications and large-capacity cellular mobile telephones. This prepares the mobile phone for commercial use.In 1979, Japan opened the world's first cellular mobile phone network. In 1982, Europe established the GSM (Mobile Communications Special Group). In 1985, the first mobile phone in the modern sense was commercially available. It places the power supply and antenna in one example and weighs 3 kilograms. Mobile phones close to modern shapes were born in 1987. Its weight is still about 750 grams, compared with today's mobile phone weighing only 60 grams, like a big brick. Since then, the "slimming" of mobile phones has become more rapid. In 1991, the mobile phone weighed about 250 grams. A mobile phone with a volume of 100 cubic centimeters and a weight of 100 grams appeared in autumn 1996. Since then, it has been further miniaturized and lightened. By 1999, it was lighter than 60 grams.

### Early market development

Before the middle of the 1990s, the prices were expensive, and only a small number of people with better economic strength could afford them, and they were bulky.
In the 90s of the last century, China did not have its own mobile phone. Nokia, Motorola, and Ericsson had three foreign companies and divided 80% of China's mobile phone market. China is only a foreign mobile phone factory.

## The Growth Phase of Mobile phone (1997-2014)

In 1990, the number of mobile phone users in China was only 18 thousand. but In 1997, it broke through 10 million key points. In 1998, mobile phone users in China added 18 million new, 12 million in 1999, about 30 million in 2000, about 300 million in 2001 and mobile phone users reached 120 million. China's mobile phone market still maintained a 40% high growth rate in 2002. . A important reason of this growth is that in 1997, Dongfang communications company set up China's first mobile phone field line, marking the start of domestic mobile phones. In October 1998, China's first domestic mobile phone KGH-2000 was finally listed, and the domestic mobile phone formally entered the market competition. Over the past 1998-2003 years, sales of domestic mobile phone manufacturers increased year by year, and occupied 5 of the market share in 5 years.
In 2005, China’s policy on mobile phones was loosened. A large number of people saw this opportunity and poured into the mobile phone manufacturing industry. After that, the growth of mobile phone users has accelerated.
In 2009, some of the country’s policies (such as the industrial revitalization plan, government-enterprise informationization, etc.) are spawning the industry user market. For example: The public security department needs police mobile phones, as well as disease prevention and control systems, urban management, industry and commerce, and taxation departments all need "informational armed forces." This will help the development of smart phones.

## The Development During Mature Phase of Mobile phone (2014-)

Smartphone (smart phone) refers to "an independent operating system like a personal computer, which can be provided by the three party service providers, such as software, games, and other users, to expand the function of the mobile phone through such programs, and to move the wireless network access by moving the communication network." The general name of a type of cell phone. In addition to mobile phone calls, smart phones have most of the functions of PDA, especially personal information management and browser based on wireless data communication, GPS and e-mail. Smart phones provide the user with enough screen size and bandwidth, not only convenient to carry, but also provide a broad stage for software operation and content service. Many value-added services can be launched, such as stock, news, weather, traffic, goods, application downloads, music picture downloads and so on.
The constant innovation and development of smart phones has given the mobile phone industry a lot of possibilities, and it may be able to maintain its growth during the mature period.

## Quantitative Analysis
### Raw Data

The data of the annual mobile phone users from the end of 1988 to 2016 is collected from National Bureau of Statistic of China and showed as below in table 1.
| Year | Users (million) |
| 1988 | 0.3 |
| 1989 | 1 |
| 1990 | 1.8 |
| 1991 | 4.8 |
| 1992 | 17.7 |
| 1993 | 63.8 |
| 1994 | 156.8 |
| 1995 | 362.9 |
| 1996 | 685.3 |
| 1997 | 1323.3 |
| 1998 | 2386.5 |
| 1999 | 4329.6 |
| 2000 | 8453.3 |
| 2001 | 14522.2 |
| 2002 | 20600.5 |
| 2003 | 26995.3 |
| 2004 | 33482.4 |
| 2005 | 39340.6 |
| 2006 | 46105.8 |
| 2007 | 54730.6 |
| 2008 | 64124.5 |
| 2009 | 74721.4 |
| 2010 | 85900.3 |
| 2011 | 98625.3 |
| 2012 | 111215.5 |
| 2013 | 122911.3 |
| 2014 | 128609.3 |
| 2015 | 127139.7 |
| 2016 | 132193.4 |
table 1 annual mobile phone users in China

### Data Analysize

Use the data to estimate a three-parameter logistic function:
S(t) = K/[1+exp(-b(t-t$_0$)]
where:
S(t) is the status measure,
t is time
t$_0$ is the inflection time
K is saturation status level,
b is a coefficient.

### Finding Proper Value of K and b

From Table 1, we know that the maximum value is 132194.3 million in 2016, so when setting K group, the value of the first K should be slightly larger than 132194.3 million, so the first value is set to 132400. After testing, the K value was chosen to be 132700, with the largest value of SQR (0.95268) in the whole set, and corresponding values of b is 0.55829. (figure 1)

### Calculating Estimated Values

Using the above formula
| China Mobile phone users | | |
| Year | Users (million) | users prediceted (million) |
| 1988 | 0.3 | 2.8 |
| 1989 | 1 | 4.9 |
| 1990 | 1.8 | 8.6 |
| 1991 | 4.8 | 15.1 |
| 1992 | 17.7 | 26.4 |
| 1993 | 63.8 | 46.1 |
| 1994 | 156.8 | 80.5 |
| 1995 | 362.9 | 140.6 |
| 1996 | 685.3 | 245.5 |
| 1997 | 1323.3 | 428.5 |
| 1998 | 2386.5 | 747.1 |
| 1999 | 4329.6 | 1300.2 |
| 2000 | 8453.3 | 2255.8 |
| 2001 | 14522.2 | 3893.0 |
| 2002 | 20600.5 | 6657.7 |
| 2003 | 26995.3 | 11214.8 |
| 2004 | 33482.4 | 18435.1 |
| 2005 | 39340.6 | 29187.1 |
| 2006 | 46105.8 | 43806.0 |
| 2007 | 54730.6 | 61403.4 |
| 2008 | 64124.5 | 79729.7 |
| 2009 | 74721.4 | 96149.3 |
| 2010 | 85900.3 | 108992.7 |
| 2011 | 98625.3 | 118012.4 |
| 2012 | 111215.5 | 123878.3 |
| 2013 | 122911.3 | 127504.6 |
| 2014 | 128609.3 | 129676.6 |
| 2015 | 127139.7 | 130953.0 |
| 2016 | 132193.4 | 131694.8 |
table 2 annual mobile phone predicted users in China

### Drawing S-curve Diagram (figure 2)
## Reference

* 1 2 The development history of mobile phone in Chinahttps://wenku.baidu.com/view/f2d96dee81c758f5f61f6715.html
* ↑ Mobile Phonehttps://baike.baidu.com/item/%E6%89%8B%E6%9C%BA/6342?fromtitle=%E7%A7%BB%E5%8A%A8%E7%94%B5%E8%AF%9D&fromid=896790#reference-%5B1%5D-5443915-wrap
* ↑ History_of_mobile_phoneshttps://en.wikipedia.org/wiki/History_of_mobile_phones
* ↑ History of mobile phones and the first mobile phonehttps://www.uswitch.com/mobiles/guides/history-of-mobile-phones/
* ↑ Technology Timeline http://about.att.com/innovation/labs
* 1 2 https://wenku.baidu.com/view/8d1d1bcba1c7aa00b52acb62.html?from=search
* ↑ http://www.sohu.com/a/194889025_765877
* ↑ https://wenku.baidu.com/view/a3d300ee19e8b8f67c1cb95e.html
* ↑ http://data.stats.gov.cn/easyquery.htm?cn=C01