Data Transmission Control Based on Hidden Markov Queuing Models

We consider a data transmission control problem for the communication network governed by a hidden Markov queuing model. The single-server finite-buffer queuing system is fed by a non-stationary Poisson stream of data packets transmitted over a stochastic channel. The service rate is proportional to the controlled transmission rate with a channel-dependent factor. Buffer overflow and channel state worsening lead to packet losses and decrease in service rate. The goal of the optimization problem is to minimize average losses tinder the constraint on the signal energy. We present an exact form for the optimal policy in the unconstrained control problem. Based on the optimal control and hidden channel state estimates, several control policies with incomplete information are proposed. They are based on two estimators (optimal filter and current queue state) and two operations (expectation and mode). Computer simulation results are presented to compare the controls obtained.