TAILIEUCHUNG - Lecture Wireless and mobile computing – Capter 28: Cellular wireless networks

The following will be discussed in this chapter: Principles of cellular networks, cellular geometries, frequency reuse, increasing capacity, macrocell and microcell, operation of cellular system, call stages, design factors, impairments, ist generation cellular networks, 2nd generation cellular networks. | Cellular Wireless Networks Lecture 28 Ovierview Principles of Cellular Networks Cellular Geometries Frequency Reuse Increasing Capacity Macrocell and Microcell Operation of Cellular System Call Stages Design Factors Impairments Ist Generation Cellular Networks 2nd Generation Cellular Networks 3rd and 4th Generation 2 Principles of Cellular Networks Developed to increase capacity for mobile radio telephone service Prior to cellular radio: mobile service was only provided by one high powered transmitter/receiver typically supported about 25 channels had a radius of about 80km 3 3 Cellular Network Organization key for mobile technologies based on multiple low power transmitters area divided into cells in a tiling pattern to provide full coverage each with own antenna each with own range of frequencies served by base station consisting of transmitter, receiver, and control unit adjacent cells use different frequencies to avoid crosstalk cells sufficiently distant can use same frequency band 4 4 Cellular Geometries 5 5 The first design decision to make is the shape of cells to cover an area. A matrix of square cells would be the simplest layout to define (Stallings DCC9e Figure ). However, this geometry is not ideal. If the width of a square cell is d, then a cell has four neighbors at a distance d and four neighbors at a distance d. As a mobile user within a cell moves toward the cell's boundaries, it is best if all of the adjacent antennas are equidistant. This simplifies the task of determining when to switch the user to an adjacent antenna and which antenna to choose. A hexagonal pattern provides for equidistant antennas (Stallings DCC9e Figure ). The radius of a hexagon is defined to be the radius of the circle that circumscribes it (equivalently, the distance from the center to each vertex; also equal to the length of a side of a hexagon). For a cell radius R, the distance between the cell center and each adjacent cell center is d = R. In practice, a .

• Quản trị mạng
• Cellular wireless networks
• Mobile computing
• Wireless and mobile computing
• Services data
• Wireless communication
• Lecture Wireless networks
• Wireless networks
• Bài giảng Mạng không dây
• Evolution of wireless networks
• 1G wireless cellular networks
• 2G cellular systems
• Fundamentals of cellular networks
• Interference and system capacity
• Channel planning for wireless system
• Channel assignment strategies
• Handoff strategies
• Block calls cleared
• Trunking efficiency
• Modern wireless communication systems
• Locating co channel cells
• Center excited cell
• Wireless WANs
• Cellular Telephone
• mobile stations
• Satellite Networks
• Networks
• Access computing
• communication services
• Wireless LANs
• Cellular Networks
• Multi Hop Wireless
• Communication networks
• Modern cellular standards
• Mobile systems
• Mobile services
• Mạng máy tính
• Lectured Computer networks 1
• Computer networks 1
• Higher layer protocols
• Wireless links
• Network
• Wireless LAN
• Cellular Network
• PCS Systems
• PCS Networks
• Radio Service
• báo cáo hóa học
• công trình nghiên cứu về hóa học
• tài liệu về hóa học
• cách trình bày báo cáo
• báo cáo khoa học
• Data communications
• Lecture Data communications
• Physical layer
• Data link layer