Electronics and Telecommunications Research Institute

Information & Communications University

Ho Yong Kang

Tae Whan Yoo

In Hwan Lee

Ju Derk Park

Cheol Sig Pyo

Hyeong Ho Lee

Kyo Hoon Son

Tae Joon Park

Nae Soo Kim

Wun Cheol Jeong

Sang Gug Lee

Hyun Kyun Choi

Eun Hee Kim

Jae Heum Lee

Man Seop Lee

Ja Won Seo

Je Soo Ko

Jong Suk Chae

Chang Sub Shin

Se Han Kim

Seong Soon Joo

Cheon In Oh

Cheo Sig Pyo

Provided is a method of improving a bandwidth of an antenna using a transmission line stub to enable long-range communication together with broadband matching. According to the method, it is possible to combine a transmission line stub in series or parallel with a feeding point, which is an antenna signal input/output point of a body serving as an antenna, and apply the transmission line stub to an antenna for wide use.

Method of improving bandwidth of antenna using transmission line stub

Disclosed is a manhole type omnidirectional antenna having a relatively small angle between a main beam direction and the Earth's surface and exhibiting omnidirectional characteristics to allow long-range communication, wherein the manhole type omnidirectional antenna includes a manhole cover installed in a manhole in the Earth's surface; a main body installed in a cavity of an upper surface of the manhole cover and configured to convert an electrical signal into an electromagnetic wave to wirelessly communicate with a gateway separated from the manhole cover; and a radome inserted into the cavity to cover the main body.

Manhole cover type omnidirectional antenna

A method of configuring a multi-superframe is provided. The method includes setting at least one parameter for configuring the multi-superframe, and configuring the multi-superframe corresponding to the at least one parameter, wherein the at least one parameter includes a superframe order (SO), a beacon order (BO), and a multi-superframe order (MO), in a form of positive integers, and the setting includes setting the MO to have a value higher than the BO.

Extended DSME MAC for low power utility monitoring service

Provided is a small switchable directional control antenna that can perform direction control according to shapes and sizes of various devices. The antenna includes a dielectric layer, a radiation patch formed on a side of the dielectric layer, a ground plane formed on a side of the dielectric layer opposite to the side on which the radiation patch is formed and configured to have a plurality of slots formed at edges thereof, and a control module insulated from the ground plane and configured to control electrical connection between the radiation patch and the ground plane.

Small switchable directional control antenna

Disclosed is a wireless communication system. The wireless communication system includes an embedded-type antenna embedded in a base, and a wireless communication unit including a communication unit that is connected to the embedded-type antenna and exchanges information with an external device, and a housing that is arranged to surround the communication unit, wherein at least one of the communication unit and the housing performs transmission and reception of electric waves as a substitute of the embedded-type antenna.

Wireless communication system

Provided are an apparatus and method of transmitting and receiving a wake-up signal. The method of receiving a wake-up signal includes the following: operating a radio frequency (RF) receiving unit that receives a wireless signal through an antenna during an SFD detecting time, wherein the SFD detecting time is shorter than a predetermined SFD detecting time period, according to the predetermined SFD detecting time period and detecting a start of frame delimiter (SFD) to indicate that the received wireless signal is a wake-up signal to wake-up a node in a sleep mode; and detecting the wake-up signal by continuously operating the RF receiving unit when the SFD is detected. Power consumption that is used to receive the wake-up signal can be reduced.

Apparatus and method of transmitting and receiving wake-up signal

Provided are an apparatus and method for charging an internal battery in a wireless sensor network. A method for a slave sensor node to charge an internal battery in a sensor network includes estimating an hourly chargeable electric energy rate in a scan phase with a master sensor node, transmitting the estimated hourly chargeable electric energy rate using an association request message requesting association with the master sensor node after recognizing the master sensor node, requesting charging from the master sensor node and performing wireless charging when a power level of an internal battery requires charging, reporting the power level of the internal battery varied by the wireless charging to the master sensor node by predetermined time periods during the wireless charging, and stopping the wireless charging when the power level reported to the master sensor node reaches a predetermined power level.

Apparatus and method for charging internal battery in wireless sensor network

Disclosed are an apparatus and method for constant amplitude encoding of a transmission signal in a CDM (Code Division Multiplexing) communication system. The apparatus for constant amplitude encoding of a transmission signal includes: an encoding module sequentially performing horizontal encoding and vertical encoding on an input signal; and a spreading and multiplexing module spreading the signal which has been encoded by the encoding module and multiplexing the spread signal in a vertical direction to output a data stream having a constant amplitude.

Constant amplitude encoding apparatus and method for code division multiplexing communication system

Provided is a burst mode optical receiver capable of accurately detecting an optical signal of minimum amplitude, by automatically controlling a gain of a pre-amplifier according to an amplitude of an input optical signal. The burst mode optical receiver can automatically control a gain of a pre-amplifier according to the amplitude of an input optical signal using an output signal of a first peak detector. In other words, when the input optical signal has a small amplitude that meets the receiving sensitivity of the burst mode optical receiver, the gain of the pre-amplifier automatically increases, thereby improving the receiving sensitivity of the burst mode optical receiver.

Burst mode optical receiver for maintaining constant signal amplitude

Provided is a communication apparatus in a PON bridge sublayer, which supports point-to-point communications between optical network units (ONU) in an Ethernet passive optical network (EPON). To support point-to-point communications between ONUs in the EPON, the communication apparatus in the PON bridge sublayer includes a second processing portion, a second input queue, a second lookup and learning portion, a second output queue, a first input queue, a first lookup and learning portion, a filtering database table a VLAN ID table, a table control portion, a first output queue, and a first processing portion.

Communication apparatus in Ethernet passive optical network

Provided is a burst mode optical receiver considering a characteristic of an extinction ratio of a received optical signal is provided. By using a peak detector considering a characteristic of an extinction ratio, top and bottom peak voltages of actual burst packets can be precisely detected while not being affected by a DC offset corresponding to an extinction ratio even though burst packets having a DC offset corresponding to the extinction ratio are received. Accordingly, waveform distortion of a signal output from the burst mode optical receiver can be minimized.

Burst mode optical receiver considering characteristic of extinction ratio of received optical signal

An apparatus for and a method of generating pointers for identifying structure boundaries of data for leased lines such as T1/E1 in an asynchronous transfer mode (ATM) adaptation layer Type 1 (AAL1) through an ATM layer. The apparatus includes a control signal generating unit for receiving a sequence number signal and a start signal, thereby generating enable signals and control signals, a next-cycle boundary generating unit for generating a next-cycle boundary value, using a pointer value and a 'Pointer_P' value adapted to store a sequence of ATM cells, a modulo calculating unit for calculating a modulo obtained by dividing the next-cycle boundary value received from the next-cycle boundary generating unit by an externally-received block size value, a current-cycle boundary generating unit for generating a current-cycle boundary value, using the next-cycle boundary value received from the next-cycle boundary generating unit, the modulo received from the modulo calculating unit, and the block size value; and the pointer calculating unit for generating a pointer value for determination of structure boundaries and a 'Pointer_P' value, to be supplied to the next-cycle boundary generating unit, based on the current-cycle boundary value received from the current-cycle boundary generating unit.

Growing community of inventors

Daejeon, South Korea

Ho Yong Kang