Development of new laser remote sensing method for global environmental problem

2003 Fiscal Year Final Research Report Summary

• Project/Area Number: 13650451
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Measurement engineering
• Research Institution: Ibaraki University
• Principal Investigator: MINATO Atsushi IBARAKI Univ., Graduate school of Science and Engineering, Associated Professor, 大学院・理工学研究科, 助教授 (00209826)
• Project Period (FY): 2001 – 2003
• Keywords: Chaos / Laser ranging / Remote sensing / Laser Diode / Modulation / Correlation

Research Abstract

In this research, we proposed a new laser ranging technique using the correlation of chaotic laser signals. Chaotic signal was produced by R, L and diode circuit. A visible laser diode was modulated by this signal. Chaotically modulated laser was divided by a beam splitter. One beam was directly detected and the other one was detected via an optical fiber or open air. We can measure the delay of beam by taking the correlation of two detected signals. First, we carried out the preliminary experiment for raging using a chaotically modulated laser diode. When the modulation of signal was 2MHz, error in the round-trip path length was 0.6m in one measurement. We assumed that the main cause of error was the sampling rate of AD conversion. Then the signal processing system was improved and the open-air experiment was carried out again. The error in the round-trip path length was improved to be 0.1m. In this paper we report the results of laser ranging experiment in the air using chaotically modulated laser diode. The monitoring of multiplex optical paths was also evaluated by numerical experiment using the measured signal of our chaotically modulated laser diode system. It was found that 10 optical paths can be multiplexed using our laser diode system.