Electronics and Telecommunications Research Institute

Soonchunhyang University Industry Academy Cooperation Foundation

Jong-Sik Lim

Chang-Joo Kim

Je-Hoon Yun

Sang-Min Han

Jung-Ick Moon

Dal Ahn

Young-Sik Kim

Soon-Ik Jeon

Yong-Tae Lee

Seung-won Kim

Joung-Myoun Kim

Sung-Min Kim

Won-Sang Yoon

Ji-Won Kim

Dae-Ung Lee

Ik-Soo Jang

Jun-Seok Oh

Seo Koo

Kwan-Sun Choi

You-Na Jang

Tae-Hoon Kang

The present invention relates to a Doherty combiner used in a Doherty power amplifier, the Doherty combiner comprising: a phase shift section connected to one end of a carrier amplifier so as to change a phase of an RF signal output from the carrier amplifier; a matching section connected to an output terminal of the Doherty power amplifier so as to impedance-match an output of the Doherty power amplifier; and a bandwidth improvement section connected to one end of a peaking amplifier so as to change at least one of a phase bandwidth and an amplitude bandwidth of the Doherty power amplifier.

Doherty combiner

A system for performing a local wireless communication using a predetermined frequency band divided into a plurality of channels. The system includes a hub for scanning each channel to identify available one of the plurality of channels and transmitting data over the available channel. The system further includes a sensor set to start to operate when the sensor detects a signal within the predetermined frequency band. The sensor spectrum-senses the signal of the frequency band for each channel, and analyzes a header of packet data for each channel, and receives and processes the packet data if the signal is identified to have a designated code.

Local wireless communication system and method employing frequency-variable signal detection

Provided is an isolation antenna for a repeater which can acquire high isolation by using loop and dipole antennas, which are positioned in opposite directions to each other based on a shielding means, in a unidirectional repeater generally used in broadcasting or wireless communications even though transmitting antenna/receiving antennas having a co-channel are set up closely to each other. The transmitting/receiving isolation antenna includes: a shielding means including an electric conductor; a first antenna of a dipole antenna type in one side of the shielding means; and a second antenna of a loop antenna type in an opposite side of the shielding means where the first antenna is positioned.

Isolation antenna for repeater

Provided is a transmitting/receiving isolation antenna that can perform wireless bi-directional communication in the co-channel, co-polarization and co-time by acquiring high isolation from transmitting and receiving antennas having co-time, co-channel and co-polarization and set up adjacently. The isolation antenna includes a first antenna; second and third antennas symmetrically positioned in the same distance from the first antenna; a shielding unit symmetrically positioned between the first and second antennas, and between the first and third antennas; and a signal removing unit for removing a signal transmitted from the first antenna to the second and third antennas.

Ultra isolation antenna

Growing community of inventors

Daejeon, South Korea

Jong-Sik Lim