Electronics and Telecommunications Research Institute

Agency for Defense Development

Sang Won Kim

In Kui Cho

Byung Jang Jeong

Je Hoon Yun

Seong Min Kim

Jung Ick Moon

Jung Sun Um

Sung Hyun Hwang

Dong Won Jang

Jae Woo Lee

Woo Jin Byun

Hoi Yoon Jung

Jang Yeol Kim

Sung J Jo

Jin Suk Pak

Jung Hoon Kim

Jeung Min Joo

Hyun Joon Lee

Dong Keun Lee

Un Seob Jeong

Jae Hyun Park

Jin Sung Choi

Dong Hyun Kim

Yong Seok Choi

Myung Sun Song

Ji Hyung Lee

Hyung Do Choi

Gwang Zeen Ko

Jung Hoon Oh

Chung Sup Kim

Sang Bong Jeon

Jae Ho Lee

Sun Hwa Lim

Ki Cheol Tae

Chang Joo Kim

Heung Yong Kang

Sunmin Lim

Changhyun Park

Sung Jin You

Kang Hee Kim

Sun Min Lim

Beom Jun Park

Man Kyu Sung

Chan Jong Park

Chan Su Lee

In Seon Kim

Jung Kak Kim

Yeon Soo Jang

Provided is a technology for increasing accuracy of position estimation by estimating a position of a signal source based on an error due to altitudes of a sensor and a signal source and an error due to a pitch of an aircraft as well as an error due to curvature of the earth. At this time, a position estimation method may include receiving measurement data from a plurality of sensors, estimating first position data of the signal source based on the measurement data, identifying an altitude error of the first position data, and estimating second position data that is data obtained by correcting the first position data based on the altitude error.

Method and apparatus for estimating position of signal source

An antenna device for magnetic field communication may include: a first coil; a second coil; a third coil; a first capacitor connected to a 1-1 terminal of the first coil; a second capacitor connected to a 2-1 terminal of the second coil; a third capacitor connected to a 3-1 terminal of the third coil; and an input port including a first input terminal connected to a 1-2 terminal of the first coil, a 2-2 terminal of the second coil, and a 3-2 terminal of the third coil, and a second input terminal connected to the first capacitor, the second capacitor, and the third capacitor.

Method and apparatus for magnetic field communication

An atomic magnetometer, which operates in a communication system using a magnetic signal in a very low frequency (VLF) band, may comprise: a vapor cell comprising one or more alkaline metal atoms; a pump light source configured to provide circularly polarized pump beams to the vapor cell; an irradiation light source configured to provide linearly polarized irradiation beams to the vapor cell; a magnetic signal detecting unit configured to detect a magnetic signal by measuring a polarization rotation angle from the linearly polarized irradiation beam passing through the vapor cell; and a bias magnetic field control unit configured to control a bias magnetic field applied to the vapor cell.

Atomic magnetometer and method of operating the same

A wireless power transmitting device includes: an upper coil including a first tubular spiral coil and a first planar spiral coil disposed beneath the first tubular spiral coil; a lower coil including a second planar spiral coil disposed to face the first planar spiral coil and a second tubular spiral coil disposed beneath the second planar spiral coil; a connecting stub configured to connect the upper coil and the lower coil to each other; and a power source configured to supply a power to the upper coil or the lower coil. The first planar spiral coil and the second planar spiral coil generate an electric field and a magnetic field in a resonance state to transfer at least some of the power from the power source to an external wireless power receiving device through the electric field and the magnetic field.

Wireless power transmitting device and wireless power receiving device

An embodiment of the present invention is a method of transmitting a multibeam jamming signal of an array antenna and including: a signal receiving operation of receiving a radar signal from a plurality of radars; a signal analysis operation of analyzing the received radar signal and identifying an angle and frequency of the signal; a control phase value calculating operation of calculating a control phase value of each array path of the array antenna for each of the identified angles; and a multibeam jamming signal transmission operation of calculating a multibeam jamming signal based on the calculated control phase value and transmitting the multibeam jamming signal for each identified frequency.

Method for transmitting multibeam steering jamming signal, and transmitting system for implementing method

Provided are an apparatus and a method for measuring a frequency of a broadband signal by using low-speed ADCs having sub-Nyquist sampling rates. A plurality of channels each including a low-speed ADC having a sub-Nyquist sampling rate (e.g. sampling frequency from several MHz to hundreds of MHz) are provided, and the frequency of an input signal corresponding to a combination of frequencies calculated through the respective channels is estimated. Therefore, as the number of channels increases, the range of measurable frequencies may be extended.

Apparatus and method for measuring frequency of signal

Disclosed is a wireless charging apparatus and method, the apparatus including a controller configured to control the wireless charging apparatus, and a transmitter configured to form a rotating magnetic field in a three-dimensional (3D) space in response to a first clock signal and a second clock signal generated under a control of the controller, wherein a phase difference between the first clock signal and the second clock signal is 90 degrees.

Wireless charging apparatus and method

Provided herein is a method and apparatus for realizing a frequency-spatial filter with variable bandwidth, the method including generating M number of FFT channel blocks having N number of channels by performing an N point FFT (Fast Fourier Transform) processing using M number of array antenna inputs; combining some of the N number of channels of each FFT channel block according to a frequency bandwidth variable parameter value; combining some of spatial response vector channels in a combined channel of each FFT channel block according to a spatial bandwidth variable parameter value; and combining all the channels and outputting the same.

Method and apparatus for designing frequency-spatial filter with variable bandwidth

A wideband transmitting and receiving apparatus including a local oscillator (LO) synthesizer providing a constant output to a wide band is provided. The LO synthesizer may generate LO signals of different amplitudes according to channels. The LO synthesizer may store the amplitudes of the LO signals different according to the channels and compensate the amplitudes of the LO signals using the stored amplitudes. Accordingly, the LO synthesizer may output the LO signals of uniform amplitudes irrespective of the channels.

Apparatus for wideband transmission and reception for multiband

A wireless communication system provides a method and device for transmitting a preamble. A transmitter generates a first preamble sequence used for frequency offset estimation and generates a second preamble sequence according to the transmission mode. The transmitter transmits the first and second preamble sequences. With respect to the second preamble sequence, the phase thereof may be shifted into different phase offsets according to the transmission mode.

Method and device for transmitting a preamble in a wireless communication system

The present invention relates to a wireless communication system and, more particularly, to a spectrum sensing method in cognitive radio communication. According to an aspect of the present invention, a method of canceling an introduced transmission signal includes generating a first signal, having an inverse phase, using a data transmission signal transmitted by a data transmission unit, adjusting a path and/or an amplitude of the first signal, and generating a first signal, having an inverse phase, using a data transmission signal transmitted by a data transmission unit, adjusting a path and/or an amplitude of the first signal, and canceling a second signal, introduced through a data receiving unit, and the first signal by the data transmission signal.

Method and apparatus for canceling introduced signal and cognitive radio communication apparatus using the same

Provided is a communication method of a secondary transmitter included in a multiple-antenna based multiple input multiple output (MIMO) cognitive radio communication system, the method including: estimating an interference channel between the secondary transmitter and a primary user in each of at least one first spectrum band that is being used in a primary system; calculating an orthogonal projection matrix to cancel interference with respect to the primary user from the interference channel; calculating an effective channel between the secondary transmitter and a secondary receiver based on the to orthogonal projection matrix; and selecting an index of an optimal spectrum band from the at least one first spectrum band based on the orthogonal projection matrix and the effective channel.

Secondary transmitter included in cognitive radio communication system and communication method of the secondary transmitter

A method and apparatus for detecting a heterogeneous communication system is provided. The apparatus include a radio frequency (RF) signal reception unit configured to receive a signal from a particular communication system, a silent duration evaluation unit configured to evaluate a silent duration between frames on the basis of the received signal, and a system type decision making unit configured to determine the type of the particular communication system on the basis of the evaluated silent duration.

Method and apparatus for detecting heterogeneous communication system

Provided are a data integration apparatus and method using a weight factor. The data integration apparatus receives sensing information from at least one sensing device, the sensing information including a value indicating the existence of signals and confidence estimated parameters indicating the degree of confidence for the value indicating the existence of signals, and then generates the weighting factor based on the confidence estimated parameters. Then, the value indicating the existence of signals and the weighting factor are used to produce characteristic values of each sensing device and to finally determine the existence of signals.

Data integration apparatus and method

Provided are an intermodulation signal generator of a power amplifier and a pre-distortion linearizer having the same. The intermodulation signal generator of the power amplifier includes: a circulator for outputting a radio-frequency (RF) input signal input via a first port to a second port and outputting an intermodulation signal input via the second port to a third port; a directional coupler for shifting phases of the input signals input via the second port of the circulator to divide or couple the phase-shifted signals; first and second Schottky diodes, disposed symmetrically, for receiving the signals divided by the directional coupler to generate intermodulation signal components; first and second phase adjusters, disposed symmetrically, for controlling phases of the intermodulation signal components gene rated by the first and second Schottky diodes by means of first and second bias voltages; and first and second scalers, disposed symmetrically, for controlling magnitudes of the intermodulation signal components generated by the first and second Schottky diodes by means of third and fourth bias voltages. The above-described intermodulation signal generator can be applied to a power amplifier of a high-performance downscaled communication system.

Intermodulation signal generator of power amplifier and pre-distortion linearizer having the same

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Daejeon, South Korea

Sang Won Kim