Priscilla Chen

Energy efficient system design with optimum transmission range for wireless ad hoc networks

In ad hoc networks, devices are required to self-organize themselves into a network without previously established infrastructure. The kind of ad hoc network we consider is made up of a multitude of relatively low mobility, short range, wireless devices, pervasively deployed throughout the environment. One of the most important design criteria for this type of network is energy efficiency. This paper looks at the energy efficiency aspect of the system design. Specifically, this paper looks at the optimum one-hop transmission distance that will minimize the total system energy. The analysis assumes that the individual devices do not have power control, but that the transmission range of all the devices as a group can be varied in the design stage. The results show that the optimum one-hop transmission distance is independent of the physical network topology, the number of transmission sources, and the total transmission distance. It only depends on the propagation environment and the device parameters. With this result, some system design trade offs can be made to minimize the total system energy. We discuss what these parameters are, how they interact with each other, and how they can be used to obtain an energy efficient wireless system. We also discuss the implications this result has for future developments of low bit rate, short range, and highly dense wireless devices for ad hoc networks.

Using optimum transmission range to design energy efficient systems for the neuRFon/spl trade/ Netform

NeuRFon/spl trade/ Netform is a sensor network made up of very low cost, low power, wireless devices (neuRFon/spl trade/ devices) that are relatively static, and are pervasively deployed throughout the environment. In this paper, we are interested in finding the relationship between the optimum one-hop transmission distance and the transceiver device parameters that will minimize the total system energy. Our analysis assumes that the individual neuRFon/spl trade/ devices do not have power control and therefore will transmit at a common range. Our results show that the optimum one-hop transmission distance is independent of the physical network topology, the number of transmission sources, and the total transmission distance. It only depends on the propagation environment and the device parameters. The implications and usefulness of this result on present day transceiver devices are also discussed.

NeuRon/spl trade/ netform: a self-organizing wireless sensor network

This paper introduces the neuRFon/spl trade/ Netform, a self-organizing wireless network for low data rate, low-power fixed sensor nodes. The protocol utilizes a logical backbone architecture through which data communications between all the network nodes are supported by hierarchical routing. We present algorithms that underpin the self-organizing features. The first algorithm constructs the optimal backbone as new nodes are introduced. The second algorithm dictates how the nodes exchange essential information for maintaining the optimal routing backbone as the network evolves. The third algorithm enables the network to recover automatically from node/link failures. The neuRFon/spl trade/ Netform is designed to work in conjunction with a low duty cycle MAC protocol, described in this paper, in order to support long battery life for wireless sensors. To illustrate the performance of the neuRFon/spl trade/ system, we present simulation results showing network formation time, data packet delivery response time, and communication duty cycles of sensor nodes for a neuRFon/sup TM/ system with 64 nodes.