Abstract-There are two principal problems in collecting data in large and sparse ad-hoc sensor networks: 1) high energy expenditure in multihop routing between widely separated nodes; and 2) routing hotspots near the destination of the data that shortens the effective lifetime of the network. In this paper, we present and analyze an alternative architecture which addresses above problems. Our approach exploits mobile nodes present in the sensor field as forwarding agents. As a mobile node moves in close proximity to sensors, data is transferred to the mobile node for later depositing at the destination of the data. Transmitting data over these much shorter distances leads to substantial power savings at sensors. This is a natural scenario for a wide variety of monitoring and dissemination applications that span large geographic areas. We investigate the advantages and disadvantages of our approach and present an analytical model to understand the key performance metrics such as data transfer, latency to the destination, and power. Parameters for our model include: sensor buffer size, data generation rate, radio characteristics, and mobility patterns of mobile nodes. The modeling results provide insights and guidelines for the deployment of such systems. Through simulation we verify that our approach can provide substantial savings in energy as compared to traditional ad-hoc network approach.
For the same architecture, an enhanced analytical model has been presented in REF .
Exploiting Mobility for Energy Efficient Data Collection in Wireless Sensor Networks
MONET
Computer Science