75 Personal and office The Difference between Fixed- to- Fixed Radio Communication Mobile communication Natural problems in mobile rad Communications. Description of Mobile Radio Systems Data Systems. Personal Communication Service Systems 75.2 Facsimile William C. Y. Lee Scanning. Encoding. Modulation and Transmission Demodulation and Decoding. Recording. Personal Computer Facsimile.Group 4 Facsimile odger E. Ziemer 75.3 Wireless Local-Area Networks for the 1990s University of Colorado at Colorado The Wireless In-Building Vision. Market Research. LANMarket Factors. Cabling Problems. User Requirements Environment Mil Ovan Product Requirements: End User Reaction. Technology 75.4 Wireless PCs Giridhar D. Mandyam Cellular Band Systems. PCS Services.3rd Generation Nokia Research Center Enhancements 75.1 Mobile radio and Cellular Communications William C.y lee The Difference between fixed-to-Fixed Radio communication and Mobile communication In fixed-to-fixed radio communications, the transmitter power, antenna location, antenna height, and antenna gain can be determined after calculating the link budget. Also, depending on the frequency range of the carrier affected on the atmospheric variation, different"margin values will be put in the budget calculation for different system applications. The fixed-to-fixed radio links are usually 10 miles or longer and high above the ground The signal variation over the link is due mostly to atmospheric changes. Satellite communications, microwave links, troposcatter, etc are fixed-to-fixed radio communications. In mobile radio communications, the param eters such as transmitter power, antenna location, antenna height, and antenna gain are determined by covering suburban areas are less than 10 miles. In mobile radio communications, the design of cell coverage is baser d an area or cell In mobile radio communications at least one end is in motion the sizes of cells in urban he average power. No margin is applied in calculating the cell coverage. Natural Problems in mobile radio Communications In mobile radio communications, there are many problems which never occur in fixed-to-fixed radio commu 1. Excessive pathloss: Vehicles are referred to as mobile units. The antenna height of the mobile unit is very close to the ground. Therefore, the average signal strength received at the mobile unit has two components, c 2000 by CRC Press LLC© 2000 by CRC Press LLC 75 Personal and Office 75.1 Mobile Radio and Cellular Communications The Difference between Fixed-to-Fixed Radio Communication and Mobile Communication • Natural Problems in Mobile Radio Communications • Description of Mobile Radio Systems • Mobile Data Systems • Personal Communication Service Systems 75.2 Facsimile Scanning • Encoding • Modulation and Transmission • Demodulation and Decoding • Recording • Personal Computer Facsimile • Group 4 Facsimile 75.3 Wireless Local-Area Networks for the 1990s The Wireless In-Building Vision • Market Research • LANMarket Factors • Cabling Problems • User Requirements Environment • Product Requirements: End User Reaction • Technology Alternatives in Meeting Customer Requirements 75.4 Wireless PCS Cellular Band Systems • PCS Services • 3rd Generation Enhancements 75.1 Mobile Radio and Cellular Communications William C. Y. Lee The Difference between Fixed-to-Fixed Radio Communication and Mobile Communication In fixed-to-fixed radio communications, the transmitter power, antenna location, antenna height, and antenna gain can be determined after calculating the link budget. Also, depending on the frequency range of the carrier affected on the atmospheric variation, different “margin” values will be put in the budget calculation for different system applications. The fixed-to-fixed radio links are usually 10 miles or longer and high above the ground. The signal variation over the link is due mostly to atmospheric changes. Satellite communications, microwave links, troposcatter, etc. are fixed-to-fixed radio communications. In mobile radio communications, the param￾eters such as transmitter power, antenna location, antenna height, and antenna gain are determined by covering an area or cell. In mobile radio communications, at least one end is in motion. The sizes of cells in urban and suburban areas are less than 10 miles. In mobile radio communications, the design of cell coverage is based on the average power. No margin is applied in calculating the cell coverage. Natural Problems in Mobile Radio Communications In mobile radio communications, there are many problems which never occur in fixed-to-fixed radio commu￾nication system: 1. Excessive pathloss: Vehicles are referred to as mobile units. The antenna height of the mobile unit is very close to the ground. Therefore, the average signal strength received at the mobile unit has two components, William C. Y. Lee AirTouch Communications, Inc. Rodger E. Ziemer University of Colorado at Colorado Springs Mil Ovan Motorola, Inc. Giridhar D. Mandyam Nokia Research Center