Research On Network Performance For Discontinuous Transmission

The next generation of mobile communication systems will support massive device connections that will consume huge amounts of energy.Discontinuous transmission is an effective method to reduce the energy consumption of the terminal and has been widely used.The basic idea of the discontinuous transmission mechanism is to allow the device to turn off its wireless transceiver circuit into the sleep mode when there is no data transmission by using the intermittent arrival of the data packet,thereby avoiding unnecessary power consumption and reducing the power consumption of the device.However,discontinuous transmission will result in an increase in delay,which in turn will not guarantee the quality of service requirements of the upper layer services.Therefore,there is a trade-off between energy efficiency optimization and reduced delay under discontinuous transmission.It is necessary to conduct in-depth research on energy efficiency and time delay under discontinuous transmission mechanism.This thesis mainly conducts in-depth research on the cross-layer energy efficiency analysis of discontinuous reception mechanism and power control and resource allocation under time delay guarantee.The main innovations are as follows:Firstly,existing discontinuous transmission analytical models are based on ideal channels,and the effects of time-varying wireless channels are not considered.By analyzing the transfer relationship between different states under the discontinuous reception mechanism,the state transition model is established by using the semi-Markov process.The state transition model is used to further analyze the stationary probability and state holding time.Based on the above analysis results,the cross-layer energy efficiency analytical model under discontinuous transmission mechanism is established.The simulation results verify the accuracy of the state transition model and show that the energy efficiency analytical model proposed in this thesis can further be used to analyze the discontinuous reception parameter optimization.Secondly,considering discontinuous transmission in 5G non-orthogonal multiple access scenario,the multi-user power control scheme is studied under delay QoS constraints.The energy efficieincy analytical model of the uplink non-orthogonal multiple access system is established and is found to be the decreasing function of the QoS parameters.Then the delay constraint function is used to solve the optimal QoS parameters under the delay guarantee.Further analysis shows that the system energy efficiency with determined QoS parameters is a pseudo-concave function of the transmit power.A multi-user energy-efficient power control scheme with delay constraints is proposed by using optimization theory.The simulation verifies that the power control scheme can guarantee the delay requirement of multiple users.Finally,considering the most common voice services in the discontinuous transmission communication system,a resource allocation method under the delay guarantee is studied.The model of discontinuous transmission communication system is established by analyzing the characteristics of voice service.Based on the effective capacity and effective bandwidth theory to calculate the QoS parameters,a resource allocation scheme to guarantee the user delay requirement is proposed.By analyzing the characteristics of the resource allocation function,the resource allocation scheme is further optimized,and the binary search algorithm is used to quickly find the optimal allocation number of resource elements.Numerical simulation results show that the resource allocation scheme proposed in this thesis can guarantee the delay requirement.