| Polling system theory is the theory of multi-queue customer service resources sharing in queuing theory. Early industrial process control instruction transmission, computer communication network channel resource allocation, scheduling and other public transport vehicles, etc. use the high reliability polling control strategy. Relevant scholars expressed that of equipment fault detection, industrial process control, multiple access control, resource allocation scheduling system by the polling system model, and using probability theory, queuing theory, stochastic processes theory to study, making it an important class of model for the practical application of analysis and study. With the rapid development of information network technology, polling system with a wider range of applications, polling systems theory has become an important control theory of the network resource allocation and MAC control protocol. Today, polling technology development, polling queuing theory obtains more new research results; this creates a larger role in promoting to communication network systems, computer systems, transportation, logistics systems and industrial process control techniques. Analyzing polling system goal is to establish the mathematical model and its functional relation that consistent with the polling control mechanism, solved exactly the expression of the mean queue length, the mean cycle time, throughput, mean waiting time delay (MWT) and other parameters of the system. In these parameters, the mean waiting delay(MWT) of a specific polling system is the most critical parameters. Among them, the MWT is the most important performance measure for analyzing the underlying system.Polling system model consists of a server and N queues, the server polls all queues in turn in the polling system, and provides services for the queue. The customer arrival process, the service time of the server, the server transfer time is random process in queuing model. The mathematical model expressed a complex system of N-dimensional probability random process. The basic polling system includes three types of service, that are gated service, exhaustive service and limited (k=1) service, limited (k=1) service polling system has more equitable service features, but the information packet waiting delay is longer. Gated service polling system has moderate features. Exhaustive service polling system has the shortest information packet waiting delay, but fairness of service is poor. In the actual communication network control protocol, most of the polling systems use a variety of hybrid control system. In recent years, polling model has been widely used in a variety of system performance analysis. In the communication and computer field, it is specifically performance evaluation criteria such as on demand, multiple access control. In the last 60 years, research indicates that polling system model has become an effective tool for analyzing system performance, and it provides a theoretical framework for resource allocation and assignment. Thanks to its impartiality, flexibility and practicality, polling systems have been widely used to analyze the performance of a variety of systems, enable this research to enrich, improve and develop. In this dissertation, M-gated service polling system control model are proposed in communication network for the balance and sudden of information packet service. The fairness of the system and information packet delay characteristics are better, but also to better handle sudden service, providing QoS guarantee. Analyzing polling system models is to set up, and derive closed form expressions to obtain the system parameters, such as the mean queue length (MQL), the mean cyclic period (MCP) and the mean waiting time (MWT). And the polling system performance results are verified through extensive simulations. Polling system gradually extended to other fields by the early equipment fault detection, that includes transportation scheduling, logistics control and management, communication networks, computer networks, wireless sensor networks, Ad Hoc networks, and social resources, etc. and it produces a positive and effective techniques promote effect. So far, the theoretical study of the polling system is still continuing to carry out and conduct in-depth some of the new model emerging, some new analytical method for constantly updated, new applications continue to expand. With coming of 21st century, the research of mobility, self-organization, high efficiency and energy saving for wireless communication becomes hot area, and the up-to-date as well efficient MAC protocol becomes an important subject.The dissertation consists of 6 parts, and it is organized as follows:Chapter 1 introduces the concept and the evolution of the polling system, the current research and the background of the dissertation.Chapter 2 introduces in detail the exhaustive service, gated service and limited (K=1) service polling systems, using the embedded Markov chain theory, the probability generating function and system state equations methodology, and gives performance evaluation. The performance of the three polling system are analyzed and compared.Chapter 3 introduces mainly the discrete-time M-gated service polling system model. Using the embedded Markov chain theory, the probability generating function and system state equations methodology, obtains the probability generating function of the queue length system and LST expression of variable waiting delay information packet. And obtains the accurate expression of mean cycle time, mean queue length, mean waiting time delay of the system. The initial parameters in the operational environment and create under the same simulation platform, using simulation results to verify the correctness of theoretical analysis; and the performance of the M-gated service polling system are analyzed and compared with gated service polling system and exhaustive service.Chapter 4 introduces mainly the continuous-time M-gated service polling system model. Using the embedded Markov chain theory, the probability generating function and system state equations methodology, obtains the probability generating function of the queue length system and LST expression of variable waiting delay information packet. And obtains the accurate expression of mean cycle time, mean queue length, mean waiting time delay of the system. The initial parameters in the operational environment and create under the same simulation platform, using simulation results to verify the correctness of theoretical analysis.Chapter 5 introduces the wireless computer networks development. Describes the IEEE 802.11 PCF control protocol analysis, the discrete-time M-gated service polling system model for the IEEE 802.11 PCF polling scheduling, improves performance of MAC control protocol. Describes the history and development of wireless sensor networks, its architecture, introduces the PCF control protocol in WSN, analyzing MAC control protocol in WSN, the continuous-time M-gated service polling system model is used to the WSN cluster polling control, and improves performance of MAC control protocol. Introduces the PCF control protocol in Ad Hoc Networks, analyzing MAC control protocol in Ad Hoc Network, the discrete-time M-gated service polling system model is used to Ad Hoc network clustering polling control, has been improved in the MAC control protocol performance.Chapter 6 draws the conclusion of the dissertation, including the main thesis of research results and make a description of the problems, and it also points out the future trends of the polling systems and puts forward some challenges.
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