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Quality of Service and Resource Allocation in WiMAXFig Part 13

Tham khảo tài liệu 'quality of service and resource allocation in wimaxfig part 13', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 13 Public Safety Applications over WiMAX Ad-Hoc Networks Jun Huang1 Botao Zhu1 and Funmiayo Lawal2 1Jiangsu University 2University of Ottawa 1China 2Canada 1. Introductions 1.1 Special needs of public safety communications Wireless communications in the public safety heavily depends on the robustness reliability availability and usability of the communication system. In the past decades this was achieved at the price of extremely high system cost and was often based on specialized solution that lacked interoperability. Faced by severe cost constraints the need to ensure interoperation of various agencies and the desire to involve existing infrastructures available the public safety community is increasingly attracted by the opportunity to utilize off-the-shelf technology in conjunction with both specialized and commercial communication systems. The most basic communication need of the public safety is radio-based voice communications. This type of communication allows dispatchers to direct personnel to areas where incidents have occurred. The trend in this marketplace has been geared towards allowing for inter-agency communication in case of large-scale disasters. The most notable large-scale response effort occurred on September 11 2001 when multiple agencies responded to the attacks in New York. The state of the most basic radio technology could not meet the increasing demand for radio communications that arose on that day. The crush of radio communications flooded the spectrum and caused massive failures across the board with regard to the base station relaying of crucial information led to more deaths of first responders. The most gripping issue regarding the state of the technology at that time was the fact that the same failures had occurred in 1993 and nothing had been done to address the issue. More focus had been put on developing faster and more lucrative consumer market and the mainstream vendors had forgot this niche space. Radio was the primary medium