Research on network technology of emergency communication based on Ad Hoc network

Abstract

Traditional emergency communication system cannot meet the status of emergency communications needs. In accordance with the requirements of the establishment of a reliable, flexible and robust emergency communication network, this paper introduces in detail the emergency communication network, the design idea and key technology based on the ad hoc network. Emergency communication can effectively deal with major natural disasters and emergencies by providing timely and reliable communication service and it has special requirements on communication and distinctive features (1): communication services highly survivable and strong adaptability, communication time of emergency and location with the meaning of uncertainty and information diversity and process of transient. The existing communication system has not fully considered the requirements and characteristics of the communication. At present, the domestic emergency communication technology is relatively backward, and the self-organized ability and survivability of the emergency communication system is low. When the communication infrastructure is not available, emergency communications support needs to be provided with the help of satellite, shortwave and trunking communication system. But it is still difficult to meet the rapid formation of reliable, efficient, robust adaptation requirements of emergency communication network of various types of user groups. As the public communication network is not reliable, and easy to cause network congestion; trunking communication system can set up fast call and support group call, broadcast call and supplementary services, but its coverage and communication capacity is small, usually confined to command and control application, and still rely on the basic communication facilities; satellite communications is vigorous and healthy, covering a wide range, but it has limited transmission capacity, high cost in deployment and difficulty in technical support. Therefore, it is necessary to introduce new techniques and methods, deploy emergency communication network rapidly, provide diversified timely manner for all types of users to meet their demand for communication services, conduct real-time monitoring of specific areas and make rapid response to emergencies, and coordinate all rescue forces after the implementation of emergency rescue and disaster relief and post disaster reconstruction. With the rapid development of information and network technology, many new techniques gradually mature and show the characteristic in the field of emergency communication, especially the extensive research of industry wireless network (wireless self organizing network and WSON). WSON is the organic combination of the mobile communication network and computer network, which has the characteristics of no infrastructure support, automatic network, multi hop relaying etc. It has stronger network survivability and flexibility, especially suitable for battlefield, remote areas, emergency and temporary communication occasions. The earliest wireless ad hoc networks can be traced back to the packet radio network developed by the american army in the seventies of the 20th century (2), then gradually emerged in the form of ad hoc networks (3), wireless sensor network (4) and wireless mesh network (5), these networks have their own characteristics and applications. Such as the hybrid network can be combined with ad hoc and cellular network on the scene emergency to improve the capacity of the communication system, expand the coverage and improve the quality of service; the network and wireless sensor networks also can be deployed in the bank, for the acquisition and monitoring of specific area in real time; emergency communication system can also be deployed based on wireless mesh network of the city.