HVAC Control in the New Millennium.pdf - HVAC.Amickracing

HVAC Control in the New Millenniumsion-multiple-access (TDMA), as well as GSM and Japan’s PersonalDigital Cellular (PDC) service. Vodaphone, which is a major UnitedKingdom mobile phone service provider has conducted field trials of asystem that integrates the GSM network with the cdmaOne interface.Software-definable radios are another possible approach.While there is not a world phone, there is growth in easy-to-upgradesoftware-based handsets. As you move around the world, youwould load different software to adapt to the phone systems you wantto use. This still requires huge doses of integration and computer power.Services based on the Universal Mobile Telecommunications StandardInstitute (UMTS) should be running in the 2-GHz band. UMTSshould deliver wide-area, high-mobility data rates of 384 kb/s and localarea,low-mobility rates up to 2 Mb/s.Almost 240 operators in over 100 countries operate GSM soEricsson, Nokia, and Siemens are all committed to the standardization ofUMTS based on GSM.The focus of UMTS has shifted from broadband integrated-servicesdigital network (ISDN) to the Internet. The first phase of UMTS shouldhave voice services augmented by data services at 144 to 512 kb/s.IMT-2000 is Europe’s proposed system that would integrate wirelesssystems, including satellites. It would optimize the use of the Internet.Japan has its own version of IMT-2000.IMT-2000 services include high-quality voice/audio, high-speeddata transmission with still images, video conferencing and multimedia.Subscribers to IMT-2000 will be able to carry on voice conversationswhile accessing a corporate Intranet, or take part in video conferenceswhile sending and/or receiving e-mail or data.Mobile InternetMobile is posed to become a major access medium for Internet andon-line services. Web browsers for cellular phones and personal digitalassistants (PDAs) are in use and thriving. Internet paging is also growingrapidly.Analog and digital cellular systems already provide circuitswitchedInternet access. Much faster direct digital connectivity will beavailable as multislot transmission over GSM networks. Another highspeeddata transmission technique for GSM is General Packet RadioServices (GPRS). It is currently working its way through the standard-©2001 by The Fairmont Press, Inc. All rights reserved.