In this study, we proposed the Incoherent Digital Holographic Imaging (IDHI) for recognition and phase information of
dedicated target. Although recent development of a number of target recognition techniques such as LIDAR, there have
limited success in target discrimination, in part due to low-resolution, low scanning speed, and computation power. In
the paper, the proposed system consists of the incoherent light source, such as LED, Michelson interferometer, and
digital CCD for acquisition of four phase shifting image. First of all, to compare with relative coherence, we used a
source as laser and LED, respectively. Through numerical reconstruction by using the four phase shifting method and
Fresnel diffraction method, we recovered the intensity and phase image of USAF resolution target apart from about 1.0m
distance. In this experiment, we show 1.2 times improvement in resolution compared to conventional imaging. Finally,
to confirm the recognition result of camouflaged targets with the same color from background, we carry out to test
holographic imaging in incoherent light. In this result, we showed the possibility of a target detection and recognition
that used three dimensional shape and size signatures, numerical distance from phase information of obtained
A simple passive optical network with ring-type distributed optical networking units (ONUs) is proposed. The ring protection is performed by a clockwise and a counterclockwise circulating fiber. The protection-and-restoration time is measured to be less than 5 s, and depends on the optical switching and the autodiscovery process time. In spite of additional devices for protection, the system reliability is enhanced so that the expected downtime decreases from 41.3 to 28.9 min/yr. The optimum condition to support the maximum number of ONUs is derived and verified by an optical link simulation.
A cost-effective and compact WDM-PON source amplification scheme with bidirectional semiconductor optical amplifier is firstly demonstrated. A linear optical amplifier is used as a bidirectional amplifier to obtain the gain clamping of downstream channels and suppress the cross-gain modulation between upstream and downstream channels. We show the experimental results including the transient responses with a dynamic wavelength channel add/drop in WDM-PON.