An On-demand QoS Routing Protocol based on Transmitter Power Adjustment in Ad Hoc Mobile Networks

Abstract

Ad hoc mobile networks are multi-hop wireless networks in which mobile nodes communicate over a shared and limited radio channel without any established infrastructure or centralized administration. For ad hoc mobile networks, two recently essential issues are how the quality-of-service (QoS), such as packet loss and bandwidth, could be guaranteed to support real-time applications and how power management is achieved in order to improve network capacity and battery life. However, much previously related work has separately addressed these two problems respectively. In this paper, we try to bring the concept of power management into the QoS routing problem in ad hoc mobile networks. To accomplish this, we propose a newly on-demand QoS routing protocol based on transmitter power adjustment. Our main idea is to adjust the transmitting nodes` powers used when transferring data packets. Considering a wireless environment sufficiently, all of the mobile nodes select channels (or time slots) for data transfer using a criterion of signal-to-interference-plus-noise ratio (SINR). These adjusted powers on reserved data slots are calculated during a route construction phase. By adjusting transmitter power, we can increase channel reuse, and thus channel utilization. Our protocol also saves the precious battery energy of portable devices. In addition, multiple routes are supported in our protocol. This could result in increasing call admission ratio. Simulation results show some advantages of our scheme as compared with different strategies in which all of the mobile nodes use the fixed and maximum transmitter power like previous works [7], [8]. In particular, about only 65% transmitter power is consumed.