Research On Emergency Communication System In Urban Underground Space After Disaster

The research and development of emergency communication systems in postdisaster underground urban spaces is receiving increasing attention from various countries.In this thesis,we design a post-disaster urban underground space emergency communication system that supports multiple communication methods and multiple data transmission for post-disaster urban underground spaces that have not collapsed and are accessible to rescuers or robots,which can transmit on-site information to remote command terminals through intelligent switching of communication and data transmission methods.At the same time,intelligent planning algorithms are used to optimize the construction of emergency networks in different scenarios,solve communication area coverage and path coverage tasks,and improve communication quality and emergency response capabilities.The main research contents of this thesis are as follows:(1)In this thesis,we use artificial bee colony algorithm to solve the communication area coverage problem in underground space,replace the initial solution of randomly generated population in bee colony algorithm by small interval generation method,and use the combination of sensitivity and pheromone to replace roulette algorithm to find nectar source,avoid the defects of bee colony algorithm such as slow convergence speed and easy to fall into local optimum,and ensure the premise of emergency communication network connectivity,and effectively improve the area coverage rate.In the experimental scenario where the radius of communication node coverage is 10 m and the area is 100m*100m,the proposed algorithm improves the area coverage by about 10% compared with the traditional bee colony algorithm.(2)This thesis solves the node deployment of communication path coverage by improving the fast search random tree algorithm,and solves the problems of more inflection points caused by random expansion and non-global optimal solutions of feasible paths by curve smoothing fitting and removing redundant inflection points,which can reduce the number of communication nodes under the premise of ensuring the connectivity of emergency communication network.In the experimental scenario where the radius of communication node coverage is 20 m and the area is 750m*750m with two different obstacles,the number of communication nodes used by the improved algorithm is reduced by about 18%.(3)In this thesis,an underground emergency communication system is designed based on Lo Ra module,WIFI module and 4G module.The system can automatically select the corresponding communication mode according to the size of the transmitted packets and the current working condition of each communication module,At the same time,priority can be given to transmitting emergency information,and rescue teams can promptly carry out rescue tasks to reduce casualties.You can also use the front-end design of the webpage to transmit information to the remote command center,achieving real-time viewing of post disaster on-site information.(4)Finally,the communication test of the underground emergency communication system proposed in this thesis was carried out in the 100*100m underground parking garage experimental site,mainly for the transmission of various types of information data such as text,voice,image and video,and the transmitted text and image information was displayed on the web front-end.The experimental results verify that the underground emergency communication system designed in this thesis can meet the demand for emergency communication in underground space.There are 71 figures,6 tables and 104 references in this thesis.