A Markov chain model for packet queueing delay analysis of a mobile user in HetNets

HetNet is a cost-efficient way to increase network capacity to support rapidly increasing data traffic. In HetNets, it is desirable to ensure that the packet delay as experienced by a user is acceptable to an application. This paper focuses on finding the packet queueing delay of a mobile user in HetNets. We develop a simple two-dimensional finite state Markov chain model to represent the queue size and data rate of a mobile user. By solving the Markov chain for its stationary state probability distribution, we can determine the average packet delay as a function of traffic arrival rate. We have verified the numerical model against results from simulations. By using the model, we can find the suitable femto cell density to achieve a desired packet delay.