Research On Multiusers Access Strategy With QoS Guarantee Under The Environment Of Spectrum Sharing

Frequency spectrum, which is a scarcest and precious resource for wireless communication systems and networks, may become more congested to accommodate diverse type of multiusers, applications, and the services in the future mobile communication networks. In actual cognitive radio networks, multimedia content sharing always include different traffic types for secondary users, such as real-time traffic and non-real-time traffic, according to their different delay characteristics. Hence, heterogeneous traffics is one of the important aspects to consider for dynamic spectrum access strategy. In addition, constraints of buffering capacity in some systems or networks have to be taken into account. Previous work does not consider these constraints of physical truth. In order to overcome these problems, the novel strategy with preemptive priority and network coding is proposed, which is used for non-real-time traffic. It can be used to improve secondary users’ throughput rates, thereby extending spectrum resources for secondary users’ and also to improve the performances in multimedia content sharing system and networks. The study indicates that the proposed strategy is significantly able to improve these performances and reduce conflict under different scenarios, including varying of primary user and secondary user arrival rates, and service time.With network coding, data arrival flows from the difference source to the destinations may be jointly coded through some intermediate nodes to achieve the maximum network information flow. While its theoretical analysis and results usually do not consider the loss performence in information transmission and processing. There is few theory to model systematically and evaluate the loss with fusion of network coding. Without such the theory, the analysis of network coding under various settings is far from practical applications. To fill the vacancy, the paper introduced the loss time slot into loss bound by stochastic networks. With the increase of data type diversity, users require a high QoS for voice/video and other applications. Hence, packet loss has become a focus in the area of industry and academia. The study has very high theory value for QoS guarantee.On the basis of the study on the key point mentioned above, we discussed quality of service for multiuser access in the next generation health network. Especially in the era of big-data, healthcare systems around the globe have undergone an increasing pressure to improve healthcare services through effective prevention, for chronic-disease patients as well as the general population. Growth of governments healthcare spending which is fuelled by an aging population, limited financial and human resources and an increase of chronic diseases. With advancement in information technology, healthcare organizations are now moving towards mobile healthcare which is an emerging field of technology that uses wireless network communication technologies to monitor patients mental and physical conditions. Although many practical problems mentioned above have been solved in healthcare networks, difficulties to handle the limitations, such as limited wireless bandwidth and quality of service, still exist. The priority-based strategies have been presented as a solution to solve such limitations, focusing on improving access probability, network connectivity, system utilization, and reliability. Based on foundation of body area network and big-data, the study considers the low cost and scalability to improve the quality of service for the users of health network.We develop an access healthcare networks mechanism of patients by classifying the personal physiological parameters. We assign three priorities to all physiological parameters and investigate the network performance under the proposed scheme, including access probability of patients and system utilization. In traditional mobile healthcare system, they usually settle the matter of rapidly increasing healthcare data through enlarge the base-station capacity. The priority-based healthcare scheme proposed in our work take the advantages of low cost and high flexibility. We consider a healthcare networks based on the priority mechanism, where patients’ sensitive personal health information were divided into three classes according to their degree of urgency. From the highest priority to the lowest, three classes of PHI (Personal Healthcare Information) are Real-Time data, Non Real-Time data and Electronic Health Records. We take advantage of concept spectrum sharing to transmit these PHI according to their respective priorities attribute. Real-time data have the highest level to reclaim any channel which is occupied by non-real-time data or EHR. EHR can be transmitted when there is idle channel. So patients with higher priority can get a real time and better service.