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In connection with the development of next-generation wireless networks based on LTE technology, demands for high-speed services are increasing leading to an exponential increase in the volume of traffic generated in mobile networks. According to the latest data from Cisco Systems, this volume will increase by 46 percent by 2021. At the same time, requirements for the level of quality of service (QoS) are increasing. The rapid growth of traffic in the conditions of providing users with a wide range of high-quality multimedia services leads to a lack of available frequency resources. This problem be-comes the main one in the development of modern wireless technologies. In this regard, cellular net-work operators offer various methods for its solution, for example, using the LAA (Licensed Assist-ed-Access) or LSA (Licensed Shared Access) systems allowing more efficient use of available frequency resources. In addition, in the framework of the implementation of various technologies to ensure the required QoS, radio resource management mechanisms (RRM) such as reducing data transmission power and interrupting users’ service can be applied. Models implementing such mechanisms can be described as queuing systems (QS) with unreliable servers. In the paper, a model of a wireless network cell is constructed, presented in the form of a QS, servers of which are in a random environment (RE). RE state can change, which is technically equivalent to a decrease or increase in the transmission pow-er. Reducing power may interrupt users’ service. Exact and approximate methods are proposed for calculating the stationary probability distribution of the model. |
