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Abstract-This study investigates the potential of using transmission power control in wireless packet networks with differing number of hops between source and destination. Here we exploit the benefits of power control in the context of multi-hop wireless ad hoc type networks with a distributed media access control. For our investigations we choose several general ad hoc network topologies and studied the effect of power control with respect to energy consumption and network capacity. We show that power control largely improves the network capacity and energy savings in all investigated scenarios, and that utilizing a greater number of intermediate hops between base source and destination improves the energy savings, but often causes a tradeoff in capacity, depending on the network topology scenarios.Keyiuovds-Power Control, Energy Saving, Multi-hop Wireless Networks, Network Capacity I. IXTRODUCTIONIt has been shown that controlling the transmission power can offer many benefits in performance. These benefits include both capacity improvements and energy savings. This paper presents a study of capacity improvements and energy savings and tradeoffs of power control in a multi-hop wireless packet network.Power control in cellular networks has been researched heavily [I], [Z] in past years, and many techniques such as those applied in CDMVIX (code division multiple access) networks are currently being used in practice. More recently, researchers demonstrated with both theoretical studies [3]and simulations [4], [5] that integrating power control into ad hoc type wireless packet networks can provide considerable benefits in capacity and energy consumption. These networks, unlike cellular networks, operate without support of fixed infrastructure. A set of wireless nodes that are distributed over a localized area constitute an ad hoc net.work if they forward each others traffic such that nodes that are out of range can communicate through intermediate nodes. These systems generally utilize a single shared channel whose access is regulated in a distributed manner by a medium access control (MAC) protocol that is integrated into each wireless node. Considerable past work has focused on tuning the M.4C protocols to maximize the channel utilization. However, more recently new protocols were proposed that integrate power control into the MAC layer for further capacity enhancement and their benefits were presented with the aid of simulation tools [6], [7].In this paper, we take the wireless ad hoc type power controlled protocol framework and extend it to evaluate the performance of multi-hop wireless networks. Utilizing multiple intermediate hops can provide extensive energy savings since transmission signals attenuate on the order of l/d4 in typical networks. Aidding power control to ,the multi-hop case can provide further savings in energy. -4s stated above, power control has been shou-n to provide significant benefits in performance for single hop wireless ad hoc networks with distributed medium access control though i...