Click on “Download PDF” for the PDF version or on the title for the HTML version.


If you are not an ASABE member or if your employer has not arranged for access to the full-text, Click here for options.

Improvement of Noise Tolerance and Positioning Accuracy Using Spread Spectrum Sound Wave in Noisy Environment

Published by the American Society of Agricultural and Biological Engineers, St. Joseph, Michigan www.asabe.org

Citation:  2010 Pittsburgh, Pennsylvania, June 20 - June 23, 2010  1009304.(doi:10.13031/2013.29848)
Authors:   Tomoo Shiigi, Naoshi Kondo, Shinji Tsuzuki, Shigeru Okada, Akira Maekawa, Toshiharu Nobara, Masao Sakakibara, Kenji Watanabe, Yuko Naniwada, Kiyotaka Okada
Keywords:   Spread Spectrum, Sound, Positioning System, Noise, BPSK

There are a lot of researches on position determination methods in room such as wireless LAN, RFID, infrared ray, TV camera, sound wave and etc. Among them, it is considered that a positioning system using sound has some merits of high measurement accuracy and low cost. In our research group, a positioning system using spread spectrum sound has been developed. So far, a system for measuring distance was developed and evaluation of its measurement accuracy was conducted. As a result of measurement under a condition of no wind, no temperature gradient and no noise, RMSE of 10m distance between a microphone and a speaker was 3.4mm. However, there are various noises, winds and temperature conditions in actual facilities such as fruit grading facilities, greenhouses, and dairy farms. It is, therefore, important to improve noise tolerance and to compensate changeable sound velocity by wind and temperature. In this paper, evaluation of noise tolerance was conducted by using three type sounds.

(Download PDF)    (Export to EndNotes)