광신호를 이용한 센서노드 위치 인식 기법에서의 광학 오차율 측정

Abstract

This paper describes a conceptual design of sensor node localization system, called "base station", for obtaining position of sensor node. The base station consists of the laser, two of beam splitters, PSD(Position Sensing Detector) and two of optical detectors with TDC(Time to Digital Convertor). The optical signal transmitted to the sensor node equipped with the CCR(Corner Cube Retro-reflector) is reflected to the base station and the PSD measures pixel data where the beam is hit. With the pixel data from the PSD and the distance data from the TDC, we can calculate the position of the sensor node. In this paper, we propose the setup to prove this localization scheme. In the experiment, for verifying this localization scheme, we change the horizontal position of the sensor node from the center position with fixing the depth element of the sensor node at 30cm distance and measure the point data from the PSD. With the given 30cm distance, we compare measurement with theoretical value and analyze the error according to the horizontal change due to the optical elements. The experimental result shows that our proposed scheme has less than few millimeter position error in the limited field of view range.