Commercial Communities

Fig. 10. Speed (90—10% fall time) vs peak wavelength for commercial communication LED emitters. Output power levels in mW are given in parentheses.

Next scheduled event Tuesday, August 14, 2001, 2-4 p.m. Daniel Siebert will be on "Vibrational Voyage." A radio program on KKUP, 91.5 FM, a non-commercial community radio station broadcasting to the San Jose/Oakland/Santa Cruz/Monterey Bay areas of California. The show is dedicated to the exploration of consciousness. Interested listeners can also catch the live show on the web via the station s web site at www.kkup.com... 

President Bush mentioned cellulosic ethanol during the 2006 State of the Union address, which sent shockwaves through the investment and commercial communities. 

There are some good reasons that trade secret protection is inappropriate here. The first is practical. Most of the developers of innovations in this biotechnology are basically highly-trained academic people who have not been sufficiently brainwashed to keep their mouths shut. This may partially disappear as this industry progresses to a more mature( ) self-aggrandizing( ) member of the commercial community. 

Ni-Hy batteries have been used in several Earth and planetary orbiting missions since the first commercial flight by INTELSAT V in 1983. Because of its demonstrated long life in GEO, this battery has been the workhorse for commercial communications satellites over the past 20 years. NASA first utilized Ni-H2 batteries in a LEO orbit when it launched the HST mission. These batteries, operating at a low 10 % DOD, have performed flawlessly since 1990. 

Japan s Hayabusa. The Boeing Satellite Development Genter bills itself as the world s leading manufacturer of commercial communications satellites, a major supplier of spacecraft and equipment, and as the supplier for weather satellites for the United States and Japan. 

Radio astronomy uses techniques for detection of radio signals from space similar to those used by radio communication systems. The radio telescope is basically the antenna that focuses the radio flux onto a detector. Electronic circuitry amplifies the detected signal. As with radio communication, the signal from multiple antennas, or multiple radio telescopes, can he combined electronically to yield more information than that which could be detected by one radio telescope alone. The similarity between the two technologies has permitted many advances in radio astronomy to be used in the field of commercial communication and vice versa. 

The technology developed for radio astronomy is virtually the same as that used for commercial communication receivers. Therefore, many of the advances in radio astronomy have commercial applications in the form of smaller, more sensitive, and less expensive satellite communication equipment. Many satellite communication companies keep abreast of the developments in radio astronomy technology to adapt this technology to produce better communication systems. 

Radio astronomy continues to be an important tool in understanding the universe. However, the sensitive radio receivers of the radio telescopes are increasingly subject to interference from commercial communication systems. Additional technologies are being developed to deal with this interference, but the interference will most likely continue to be a problem and become worse at established radio observatories. Plans to build new radio observatories in even more remote locations will probably forestall the problem of interference but will not end it for ground-based radio astronomy. 

Commercial communication system designers initially ignored SS techniques. Spread spectrum systems were considered exotic, expensive, and necessary only when hostile parties were attempting to jam or intercept the communication signal. This attitude toward SS techniques has changed within the past few decades for a number of reasons as outlined in Sec. 12.6.7 to follow. Although miUtary and commercial users have different motivations, the technical problems faced by these systems are very similar. Table 12.13 summarizes these similarities. 

Li-ion/UCAP hybrid systems with high power and long hfe would benefit multiple military and commercial communication satellite applications as well as selected Hybrid Electric Vehicle (HEV) and Electric Vehicle (EV) applications. 

Power requirements for space-based or satellite-based batteries are strictly dependent on the type of satellite, such as commercial communications satellites, military... 

The battery power requirements are very high because the communication satellites are complex and are equipped with multiple voice and high data channels in addition to the large variety of electronic and electrical sensors and devices aboard the satellites [5]. Battery power requirements for commercial communication satellites launched before 1980 are moderate, as noted in Table 2.13. 

The United States launched an advanced communications satellite known as the INTESAT-IV system in the 1990s, which represented a fourth-generation commercial communications satellite, incorporating the latest radiofrequency and digital components with minimum weight, size, and power consumption. This system offers specified communications service requirements and can be used in support of future manned space flight missions. Frequency operating bands and secondary battery power requirements for this particular communications satellite are summarized in Table 2.15. 

Performance Capabilities of the Commercial Communications Satellite System... 

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