Radio propagation patterns in wireless sensor networks

Wireless sensors use low power radio transceivers due to the stringent constraints on battery capacity. As a result, radio transmission with wireless sensors is unreliable. Further, propagation patterns are irregular, causing some links to be asymmetric. Accurate models of radio propagation patterns are important for protocol design and simulation. Thus far, measurements of radio propagation patterns have been carried out using the motes themselves for test measurement. We have carried out experiments using RF test equipment to precisely measure mote transmit and receive signal strength and to accurately determine propagation patterns. Our tests have produced new radio propagation patterns and a new propagation model. Our model is more accurate than previous models and can be used for building both analytical and simulation models for wireless sensor networks.