Electronics and Telecommunications Research Institute

Chang-Sub Shin

Jong-Suk Chae

Cheol-Sig Pyo

Hyun Woo Lee

Hyun Jun Lee

Hyun Sup Lee

Jong-Hyun Park

Woo-Yong Lee

Anseok Lee

Seong-Soon Joo

Wun-Cheol Jeong

Hyun-Seo Oh

Byung-Tae Jang

Kyeong-Tae Kim

Kyung-Bok Sung

Jung-Sook Kim

Jae-Han Lim

Won-Chul Choi

Kwang-Ho Ko

Choon-Sik Yim

Han-Byeog Cho

Hyuk-Joon Lee

A method of operating a device capable of periodically hopping a predetermined interval using a channel hopping sequence in order to improve low radio frequency (RF) reliability caused by single frequency based channel access.

Operating method for a WPAN device

Provided are a reliability-based, real-time sensor network medium access control (MAC) communication system and method using a superframe. The superframe includes an active duration which is a time duration in which a communication is established, and a sleep duration which is a time duration in which no communication is established. The active duration includes a beacon block in which a plurality of beacon transmission nodes are respectively allocated beacon slots for transmitting a beacon frame, and a forwarding block in which each of sinks nodes is allocated a slot for unifying data regarding the sink node and data regarding sensor nodes managed by the sink node and transmit the result of unifying in order to establish a communication between the sink nodes and between each of the sink nodes and a base station.

Reliable and low-latency sensor network MAC system and method using superframe

A highly precise clock synchronization apparatus in a real-time locating system (RTLS), includes an optical transmitting/receiving unit for receiving a clock information frame from a clock synchronization server, converting the received clock information frame in series-parallel, and transmitting/receiving the clock information data and the clock information; an offset estimation unit for detecting a preamble signal and a clock information signal from the series-parallel converted clock information frame, calculating a phase difference value by comparing the detected preamble signal with the detected clock information signal, and outputting an offset value based on the calculated phase difference value; and a clock synchronization unit for updating a local clock value to a time of the clock synchronization server based on the offset value and the clock information frame.

Apparatus for synchronizing clock in real-time locating system and method therefor

Provided is a Media Access Control (MAC) forwarding method for multi-hop routing in a communication system between vehicles. The method includes the steps of: a) receiving a frame from all nodes and checking whether there are duplicate frames; b) partly updating forwarding cache table (FCT) information, or updating SNT information and checking whether a destination address is a corresponding node; c) updating the FCT information, transmitting an Ack signal and transferring the frame to the upper layer, or searching whether the destination address is registered as 'd_addr'; d) updating the FCT information and transmitting a delay ACK frame or checking whether the transmitted frame is a flooding frame; and e) updating the FCT information, checking whether the other node does not transmit the 'd_ack' and inserting a flooding frame, otherwise, updating the FCT information and abandoning the frame.

MAC forwarding method for multi-hop routing in communication system between vehicles

Disclosed are a base station and a mobile terminal for location detection, and a location detecting method. The base station in which a plurality of antennas having RF modules are installed transmits a signal including location information of each of the antennas to the mobile terminal. The mobile terminal carries out location detection by selectively using location information received from a GPS receiver or location information received from a DSRC transceiver. The base station and mobile terminal for location detection can perform location detection with high accuracy using the existing DSRC service. Thus, the base station and mobile terminal can carry out location detection having an error of approximately 10 m in downtown areas or buildings.

Base station and mobile terminal for location detection, and location detecting method

Growing community of inventors

Daejeon, South Korea

Chang-Sub Shin