Chapter Overview
Wireless was the original word for "radio." Essentially, it meant wireless telegraphy. The term was widely used in the early twentieth century but fell out of use in the United States and was almost entirely replaced by the word radio before World War II. But today the term wireless is back in a big way. It still means "radio," but it has some specific modern implications. Nowadays, wireless refers primarily to the enormous cellular telephone industry. After all, cell phones are basically sophisticated two-way radios.
With over 800 million cell phones sold in 2005, the cell phone is the largest-volume consumer electronics device. It has changed the way that we communicate. Also 2005 was the year in which cell phone subscribers numbered more than wired telephone subscribers. Furthermore, as the data speed of the newer digital cell phone transmissions increases, more cell phone applications are possible. These include cameras, Internet access, e-mails, audio, gaming, and video. This chapter provides a technical overview of cell phone standards and operation. Other short-range wireless technologies are covered in Chap. 21.
Chapter Outline
20-1 Cellular Telephone Systems
20-2 Advanced Mobile Phone System (AMPS)
20-3 Digital Cell Phone System
Chapter Objectives
- Describe the cell phone operational concept.
- Name the three most common second-generation digital cell phone systems and describe the features of each.
- Define the cell phone terms 2G, 2.5G, 3G, and 4G.
- Describe the block diagram architecture of a modern 2.5/3G digital cell phone.
- State the features and benefits and applications of 3G cell phones.
- Explain the applications and benefits of location-based technologies in cell phones.
- Describe the architecture and operation of a cell phone base station.