Research of acoustic ranging signal' TOA estimate algorithm in wireless sensor network

摘要

Several acoustic ranging signals' TOA (time of arrival) detection methods are researched and a new method based on the digital signal rectifying process is introduced. It is used in the wireless sensor network's node self localization, includes the following steps: increase signal noise ratio, remove DC (direct current) value, full-wave rectifying process, low-pass filter process and TOA estimate. It has been implemented with a dsPIC6014A microcontroller. Test results show that the estimate error of TOA is less than 3.5% with 30 meters distance when the time of computing was about 1.5 seconds (10MHz clock) and the sample length was 4096 (12bits of each sample data)points.