Dynamic channel allocation optimization using a closed loop power control in CDMA TDD systems

Standard scheduling algorithms to optimize the resource allocation in a time division duplex (TDD) consider only the traffic situation and the priority of different services. However it is necessary to take into account the time varying nature of wireless channels and the power control (PC) algorithms used to counteract interference limited systems like CDMA. PC can be open loop power control (OLPC) or closed loop power control (CLPC), the latter one is preferable especially in presence of a real time traffic and fast fading channels. Here, we propose new scheduling algorithm which allocate up-link (UL) and down-link (DL) slots in order to use efficiently CLPC, while the resource unit (code and slot) are selected taking into account quality of services requirements (e.g. delay) and the corresponding channel state.

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