Korea Advanced Institute of Science and Technology

Samsung Electronics Co., Ltd.

Jin Serk Baik

Chang Hee Lee

Sang Mook Lee

Joon Oo Kim

Seung Hyun Jang

Won Suk Yang

Yun Je Oh

Do Young Ha

Kwang Pyo Hong

Sung Kweon Park

Hyun Sik Min

Jeong Rok Park

Sung Man Kim

Ki Man Choi

Sil Gu Mun

Keun Youl Park

An indoor location system having a sensor and a method for checking an indoor location using the indoor location system are disclosed. The method includes: calculating a current location coordinate by using nodes; calculating a first movement distance by comparing the current location coordinate and a stored previous location coordinate; calculating a second movement distance through a sensor; and storing the current location coordinate instead of the previous location coordinate when the distance between the first movement distance and the second movement distance is smaller than a predetermined threshold value. Accordingly, an accurate location of an object can be recognized indoors and an error can be prevented from being caused when the location of the object is recognized.

Indoor location system having sensor and method for checking location using the same

The present invention relates to a passive optical network, which inexpensively improves the spectral efficiency of an access network and is capable of increasing the number of subscribers per channel by using WDM in combination with Time Division Multiplexing (TDM) or SubCarrier Multiple Access (SCMA) to expand a conventional WDM passive optical network. The passive optical network includes light providing means provided in a central office to provide broadband incoherent light; a multiplexer connected to the central office via an optical fiber to divide the light transmitted from the light providing means according to wavelengths and to multiplex upstream signals; a plurality of splitters to branch divided lights and to combine the upstream optical signals; and a plurality of subscribers connected to the splitters, the subscribers including wavelength-locked Fabry-Perot laser diodes capable of performing direct and analog modulation, and means for directly modulating lights of the Fabry-Perot laser diodes and transmitting modulated lights to the subscribers using time division multiplexing.

Optical access network using wavelength-locked WDM optical source injected by incoherent light

An optical network terminator of the present invention includes an optical wavelength division multiplexer for receiving an optical signal and incoherent light. An optical detection unit converts a downstream high speed and low speed optical signals into electrical signals. A laser diode converts an upstream signal into an optical signal. A high speed driving unit is supplied with power from a power supply unit to drive a forward-biased laser diode and establish a data and video channel. A high speed reception unit is supplied with the power to receive a downstream data and video channel. A charging unit outputs charged power at the time of a power failure. A low speed driving unit is supplied with the charged power to reverse-bias the laser diode to establish a voice channel. A low speed reception unit is supplied with the charged power to receive a voice channel.

Optical network terminator and optical network connection method using it

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Ansan-si, South Korea

Jin Serk Baik