Comparing adaptive-power and adaptive-rate MACs for wireless ad-hoc networks

There are two approaches in designing MAC protocols: adaptive-power and adaptive-rate MACs. In adaptive-power MACs transmission power is changed upon nodes´ distance in order to reduce energy consumption. In adaptive-rate MACs transmission rate is changed in order to improve throughput. Recent adaptive-power protocols suggest varying the transmission power such that the RTS/CTS handshake is done at the maximum and the data-ACK are transmitted at the minimum necessary transmission power level. It has also been suggested to periodically use maximum transmission power during data transmission (PCM MAC). In this paper we show that although adaptive-rate MACs are designed to increase throughput but they are also more power-efficient than adaptive-power MACs with maximum RTS-CTS power