Research On Cognitive Transmission And Application Of Heterogeneous Networks In Large Public Buildings(Groups)

The measurement and control system of the large-scale public buildings(group)are always contains many intelligent building sub-systems and the communication equipment are always numerous and complicated.The indicators of the Quality of Service(QoS)are significantly different in each sub-system.Communication equipment and QoS are heterogeneous.Furthermore,the electromagnetic environment of the public environment is complex and varied,which has highly uncertainties.This paper focus on the research that cognitive transmission of heterogeneous wireless network in large-scale public buildings(group)and the application technologies.This paper combines the large-scale public buildings(group)with the network deployment and establishes the corresponding network topology model,named line-star network topology model based on retransmission and multi-channel technologies.In addition,this paper also builds a test platform and a basic application system.Based on the established network topology model and platform,combined with cognitive transmission theory and technology,the three main researches are concluded as follows: 1)With the respect to the difference of the communication transaction cycle in the network,we proposed the multi-period communication scheduling model and designed the multi-period scheduling policy based on genetic algorithm.2)The problem of the single-hop network transmission fairness was proposed based on the star network with retransmission in the model.To solve the problem,an optimized time slot allocation scheme based on genetic algorithms was proposed,which optimized the allocation of time slots with the probability of successful device and network communication transmission under the deterministic time slots as to improve the reliability of communication networks.3)A multi-hop transmission model was proposed based on the linear network topology.The parallel transmission scheduling is implemented in multi-hop network and the QoS simultaneously transmits on the non-interfering link as to save the transmission time slots.This paper verifies the effectiveness of all the proposed algorithms based on Matlab and local experimental platforms.In the multi-period scheduling problem,the scheduling method with genetic algorithm chooses the minimum number of slave nodes effectively in the polling cycle as to save bandwidth.In the single-hop type network,the genetic algorithm optimizes the allocation of link time slots and achieves the fairness of the star network transmission.In a multi-hop network,the genetic algorithm optimizes the allocation of link timeslots,and implements the parallel transmission of the QoS on the non-interfering links.