Accurate acoustic localization with two binaural recorders

Animal vocalization can be used to locate animal position, which is a low interference and noninvasive method in animal monitoring．This method for triangulating the position of wild animals has been established previously, but always involve expensive and cumbersome hardware, therefore limiting the widespread use of the method．Here an acoustic location system based on two dual-track recorders was used．The optimal distribution of microphones was obtained．When the midpoint of two baselines connecting two microphones from the same recorder coincides, the monitoring range reaches a maximum．The accuracy of acoustic location was also considered．To improve precision of acoustic localization, one should include the influence of ambient temperature on sound velocity, improve localization precision of microphones, reduce measurement error of time difference, increase distance between microphones from the same recorder, and avoid extension of baselines passing through animal activity area．Judging from the playback calls from Passer cinnamomeus and Pardaliparus venustulus, location accuracy could reach (0.806 ± 0.259) m and (0.781 ± 0.293) m respectively．