Travis will be presenting two papers at the Internoise 2008 conference next week. The papers are entitled "Experimental Characterization of Sound Propagation in a Dense New Zealand Forest" and "Long Range Identification of Wildlife Using Phased Arrays of Microphones: A Feasibility Study".
The first is a study which measures the sound attenuation of the very dense forests on New Zealand; that is, how quickly a sound decreases in sound pressure level over distance. We found that sound is attenuated more in the native forests of the Hunua Ranges than in any forest in the literature, at approximately 0.5 dB/m.
The second paper investigates the feasibility of locating birds by their calls, with the particular application of finding the location of kokako in the Hunua Ranges. Due to the high attenuation of sound through the forest, we investigated a scheme which would place arrays of microphones on towers above the canopy. This was compared to a more traditional method of installing a grid of individual microphones near the forest floor. This work used the forest reverb model seen earlier on this blog.
Details to follow.