Novel power and time allocation algorithm for a Dynamic TDMA slot assignment multiuser transmission schemes

In the literature, many design parameters have been utilized in network optimization but till now little attention has been paid on the buffer management in the base station. In this paper, we propose a new power allocation algorithm suited for Dynamic Time Division Multiple Access (TDMA) scheme, that is based on the minimization of the total transmitted power under the constraint of ensuring the buffer stability since the buffer overflow is one of the important causes of traffic outage and so the throughput degradation. We show that this optimization problem can be efficiently solved througth using the convex optimization techniques. The global optimal minimization solution can be computed numerically since the objective and the constraint functions are non linear. We can ensure the power control by adding an upper bound on the transmitted power. The new formulated problem can be used for admission control. Since the optimization problem is no longer convex, we propose a simple heuristic algorithm to solve it. Simulation results are given to support our claims and to illustrate the good performance at the level of power allocation obtained by the proposed allocation schemes.

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