Commercial wireless

VCO/synthesizer. (Courtesy of National Semiconductor. DuPont Application Note Reference H-67767.) 

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Figure 1.23 and Figure 1.24 are examples of modules designed for use in the 900-MHz to 2.4-GHz range. New commercial wireless applications of ceramic technology continue to emerge for RF front-end modules, filters, antenna switches, and radio modules. 

As the commercial wireless market began to emerge, it was recognized that standard high-frequency test methods for material characterization were... 

Simultaneous UV and MW irradiation of the sample Possibility of performing photochemistry at high temperature Good photochemical efficiency — the EDL is inside the sample Simplicity of the experiment and the low cost of the EDL Use of a commercially available microwave oven Wireless EDL operation... 

Rao et al. [140] described a study using a commercial pH sensitive radio-telemetry capsule (RTC) to evaluate small bowel and colonic transit time in athletes with gastrointestinal symptoms. The RTC (type 7006 Remote Control Systems, London, UK) consists of a glass electrode with an integral reference cap and battery. RF transmissions from the capsule are detected by a solid-state receiver worn on the belt of the patient. The recorder samples the pH from the capsule at 6 second intervals for a period of 24 hours. They used pH changes as an indication of the pH capsule s movement. A sharp rise in pH from around pH 2 to pH 6 indicates that the capsule has moved into the duodenum from the stomach. Then the pH progressively rises to a plateau around pH 8, which indicates that the capsule has moved into the terminal ileum. Another commercially available wireless pH sensor (Bravo) from Medtronic Inc. has been used to measure esophageal pH for a period of 48 hours and it will be discussed later. 

Potential vulnerabilities in control systems are exacerbated by insecure connections. Organizations often leave access links—such as dial-up modems to equipment and control information—open for remote diagnostics, maintenance, and examination of system status. Such links may not be protected with authentication or encryption, which increases the risk that hackers could use these insecure connections to break into remotely controlled systems. Also, control systems often use wireless communications systems, which are especially vulnerable to attack, or leased lines that pass through commercial telecommunications facilities. Without encryption to protect data as it flows through these insecure connections or authentication mechanisms to limit access, there is limited protection for the integrity of the information being transmitted. 

The pace in the development of electromagnetic field (EMF) technologies and the ever-increasing number of commercial applications in all areas and activities of our life is breathtaking. This is particularly true of radio frequency wireless technologies and telecommunications. Nowadays, especially in urban environments, exposure to human-made EMFs is an unavoidable fact of life, and understanding its potential health effects and possible environmental impacts and risks, a priority. 

The wireless phone network and the cellular phones that use it got their commercial start in the United States in the early 1980s (see Fig. 3-5). In 1984, there were 346 cellular transmission sites in the United States and 91,600 subscribers. It took only 20 years for nearly half of Americans to access the cellular phone network. By December 2002, there were nearly 140,000 cellular transmission sites and over 140 million U.S. subscribers. The change in geographic distribution, and in particular the increase in density, of the cellular transmitter sites is shown in Fig. 3-6. 

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