Wireless Sensor and Actuator Networks: Algorithms and Protocols for Scalable Coordination and Data Communication

2.10 MINIMAL ENERGY BROADCASTING

Broadcasting was discussed so far with the hop count as the metric of their performance. An alternative metric, often used in the literature, is the power for transmission and reception between nodes. It can be used if nodes can adjust their transmission powers, which we assume for this section. The problem of selecting forwarding nodes, and their transmission radii, so that all nodes in the network receive the message, and the total power used for these transmissions is minimized, is known as the minimal energy broadcasting problem. Detailed surveys of existing solutions can be found in Ingelrest et al. (2005) and Liu et al. (2005) (see also Stojmenovic et al., 2007 for few additional solutions).

Wieselthier et al. (2000) described centralized broadcast incremental power (BIP) algorithm. It is the most popular among several dozens of existing centralized solutions. In BIP, nodes are added one at a time into an existing growing tree, so that the additional power at each (incremental) step is minimized. There are two options: to add new transmission, or to increase transmission radius of existing transmitting node, so that a new node is added with the smallest possible additional energy. broadcast incremental power and other proposed methods in practice behave like MST since 2 ≤ α in power metric model p(d) = d^α + c, for link at distance d, unless c is significant with respect to network density. The major disadvantage of centralized algorithms is ...