tailieunhanh - Adaptive Antenna Tutorial: Spectral Efficiency and Spatial Processing

Temporal/Spectral aspects are mature, well understood, well exploited: no significant future improvements in spectral efficiency here; proper application is important | FCC Office of Engineering and Technology 7 September 2001 Marc Goldburg CTO, Internet Products Group ArrayComm, Inc. marcg@ Adaptive Antenna Tutorial: Spectral Efficiency and Spatial Processing Switching/Routing Cellular Technology cell sector Cellular networks divide a coverage area into multiple “cells” each has its own radio infrastructure and users Basis for most two-way wireless services cellular phones (1G, 2G, 3G, ) MMDS broadband data (Sprint, Worldcom) Wireless LANs LMDS broadband data (Teligent, Winstar, ) Switching/Routing Data Networks Telephony Networks Backhaul Network base station Motivation For This Talk Cellular system design trades off competing requirements service definition service quality capacity capital and operating costs resource requirements including spectrum end-user pricing/affordability coexistence with other radio technologies Adaptive antenna technology fundamentally changes the nature of this trade-off Outline | FCC Office of Engineering and Technology 7 September 2001 Marc Goldburg CTO, Internet Products Group ArrayComm, Inc. marcg@ Adaptive Antenna Tutorial: Spectral Efficiency and Spatial Processing Switching/Routing Cellular Technology cell sector Cellular networks divide a coverage area into multiple “cells” each has its own radio infrastructure and users Basis for most two-way wireless services cellular phones (1G, 2G, 3G, ) MMDS broadband data (Sprint, Worldcom) Wireless LANs LMDS broadband data (Teligent, Winstar, ) Switching/Routing Data Networks Telephony Networks Backhaul Network base station Motivation For This Talk Cellular system design trades off competing requirements service definition service quality capacity capital and operating costs resource requirements including spectrum end-user pricing/affordability coexistence with other radio technologies Adaptive antenna technology fundamentally changes the nature of this trade-off Outline Spectral Efficiency and System Economics Adaptive Antenna Fundamentals Adaptive Antenna Technologies Adaptive Antenna Performance Determinants Adaptive Antenna Regulatory Issues Summary Spectral Efficiency Defined A measure of the amount of information – billable services – that carried by a wireless system per unit of spectrum Measured in bits/second/Hertz/cell, includes effects of multiple access method modulation methods channel organization resource reuse (code, timeslot, carrier, ) “Per-Cell” is critical fundamental spectral efficiency limitation in most systems is self-generated interference results for isolated base stations are not representative of real-world performance Why Is Spectral Efficiency Important? Spectral efficiency directly affects an operator’s cost structure For a given service and grade of service, it determines required amount of spectrum (CapEx) required number of base stations (CapEx, OpEx) required number of sites and associated site maintenance (OpEx) .