The major difference between underwater sensor networks (UWSNs) and terrestrial sensor networks is the use of acoustic signals as a communication medium rather than radio signals. The main reason behind this is the poor performance of radio signals in water. UWSNs have some distinct characteristics which makes them more research-oriented which is the large propagation delay, high error rate, low bandwidth, and limited energy. UWSNs have their application in the field of oceanographic, data collection, pollution monitoring, off-shore exploration, disaster prevention, assisted navigation, tactical surveillance, etc. In UWSNs the main advantages of protocol design are to a reliable and effective data transmission from source to destination. Among those, energy efficiency plays an important role in underwater communication. The main energy sources of UWSNs are batteries which are very difficult to replace frequently. There are two popular underwater protocols that are DBR and EEDBR. DBR is one of the popular routing techniques which don't use the full dimensional location information. In this article the authors use an efficient area localization scheme for UWSNs to minimize the energy hole created. Rather than finding the exact sensor position, this technique will estimate the position of every sensor node within certain area. In addition to that the authors introduced a RF based location finding and multilevel power transmission scheme. Simulation results shows that the proposed scheme produces better result than its counter parts.
