Carolyn N. Kinder
APPENDIX A: A Brief History of Cellular Phones
1947-The basic concept of cellular phones began. Bell Laboratories introduced the idea of cellular communications in with the police car technology.
1968-The FCC reconsidered its position in 1968, stating "if the technology to build a better mobile service works, we will increase the frequencies allocation, freeing the airwaves for more mobile phones
1973-Dr Martin Cooper, a former general manager for the systems division at Motorola, is considered the inventor of the first modern portable handset. He made the call to his rival, Joel Engel, Bell Labs head of research.
1977-AT&T and Bell Labs had constructed a prototype cellular system.
1979 -The first commercial cellular telephone system began operation in Tokyo.
1981- Motorola and American Radio telephone started a second U.S. cellular radio-telephone system test in the Washington/Baltimore area.
1982- The slow-moving FCC finally authorized commercial cellular service for the USA.
1987- Cellular telephone subscribers exceeded one million and the airways were crowded. During that time, three ways of improving services existed: 1) increase frequencies allocation; 2) split existing cells and 3) improve thetechnology.
1988- The Cellular Technology Industry Association (CTIA) was established to work with the cellular service operators and researchers to identify new technology requirements and set goals.
1991-The Telecommunications Industry Association (TIA) created a standard specification based on the requirements the CTIA had recommended. The TDMA Interim Standard 54 or TDMA IS-54 was released.
1994- TDMA IS-136 uses the frequency bands available to the wireless network and divides them into time slots with each phone user having access to one time slot at regular intervals
Source: Adapted from ATT Cellular Telephone Equipment Installation Course-CL. 3403, CA. 1985. Updated 1995.
APPENDIX B: The Electromagnetic Spectrum
nm = nanometer (1nm= .000 000 001 meter
m = micrometer (1m = .000 001 meter)
mm = millimeter (1mm = .001 meter)
m = meter (1m = 39.37 inches)
km = kilometer (1km = 1000 meters)
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Violet Yellow Red Near Infared
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Blue
Green and Orange
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400nm – 500nm 600nm – 700nm 800nm
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Visible Light
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X-Rays Ultraviolet Infared
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1nm - 10nm
100nm – 400nm
100m - 1mn
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Wavelength: This is a chart of the electromagnetic spectrum that will assist teachers with the teaching of electromagnetic waves.
Source: Forrest M. Mines, III. Science and Communication Circuits and Projects . "Sound". Radio Shack. 2000.
Some of these books are available from-on-line bookstores, such as "Amazon"
