A Transmit Power Control Algorithm for Data Acquisition Systems

Recently, wireless many-to-one networks have been attracting much attention and wireless sensor ad-hoc networks are applied to various applications. In ad-hoc networks using carrier sense multiple access with collision avoidance (CSMA/CA), the capacity is drastically decreased by the hidden node problem. In this paper, we assume a many-to-one network and propose a transmit power control (TPC) algorithm to avoid the hidden node problem. In our proposed TPC algorithm, a 1-hop area, a forced multi-hop area, and a multi-hop area are defined. All nodes in the 1-hop area adjust their transmit power as they can sense each other's transmit data, and all nodes in the forced multi-hop area and multi-hop area control their transmit power as they connect to a gateway (GW) with multi-hop and reduce the interference to nodes in the 1-hop area. The network capacity using the proposed TPC algorithm is evaluated by computer simulation. By this computer simulation, it is shown that the network capacity of TPC is better by about 2.6 times than that of No-TPC.