Joint Power Allocation And Data Routing In Wireless Sensor Networks

With the rapidly development of wireless communicational technology and low-power embedded system, a rising distributed network has raised attention widely. Wireless sensor network(WSN) is a network constructed by a huge amount of sensor nodes, which communicated to each other by wireless. WSN is also a self-organized network with multiple hops.The common application of WSN is collecting data from the sensing area. This kind of data collection contributes a special communication paradigm, which is called "Convergecast". The most important research fields in WSN include energy-efficiency, bandwidth and convergecast. The key of convergecast in WSN is to schedule the routing decision of each node, constructing a convergecast tree. Previous convergecast algorithms only focused on minimizing the energy cost without considering the constraint of wireless bandwidth. This article shows that constructing a congestion-free convergecast tree cannot ignore the bandwidth constraint. Considering the adjustable transmission power of sensor nodes, it will affect not only the topology of networks but also the bandwidth of wireless links.In this paper, we formulate the Minimum Total Transmission Power(MTTP) problem, which aims to address the issue of constructing a congestion-free convergecast tree in WSNs with adjustable transmission power of sensor nodes. We transform MTTP to an Integer Linear Programming(ILP) model, by which the optimal solution to MTTP is derived. To strike a balance between scheduling overhead and system performance, we propose a heuristic algorithm called Nearest-to-Sink, which searches viable paths in a greedy way and achieves near optimal performance.We build the simulation model and give a comprehensive performance evaluation, which demonstrates the feasibility and the effectiveness of the proposed algorithm..