A South Korean research team has developed the world’s first co-channel repeater based on the North American ground wave standard “ATSC 3.0”. This development will be a huge help in securing infrastructures for UHD broadcasting and increasing status of relevant national technologies.
Electronics and Telecommunications Research Institute (ETRI, President Kim Myung-joon) announced on Wednesday that the institute has developed the world’s first co-channel repeater based on ATSC 3.0 after developing ATSC 3.0 transmitter and receiver for professional.
Repeater amplifies radio waves from transmitting station and retransmits them. It can be installed in an area where radio waves are blocked off and allows residents in the area watch TV channels. The co-channel repeater developed by ETRI is able to retransmit repeating signals at a same frequency as transmitting station.
However, there needs to be a technology that can remove interfering signals from using same frequency.
The research team from ETRI solved the problem by applying “adaptive array antenna technology” that can amplify necessary signals and control interfering signals by using six antennas. The output of the repeater has been raised by increasing separation between antennas.

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<The concept of co-channel repeater based on ATSC 3.0>

The repeater has a high interfering signal removing capability of 28dB which is a key indicator for performance. The difference in “input output modulation error ratio (MER)”, which is an indicator for quality of output signal, is within 3dB that makes the repeater one of the best repeaters in the world.
The research team told the Electronic Times that it believes that transmitting stations located in poor surroundings will be able to relay high-quality signals by using a technology that is able to recover distorted signals back to their original status.
This technology is certified by KBS Broadcasting Equipment Certification Center back in June and it is currently used by transmitting stations of KBS located in radio-shadow areas. The repeater will be sold in South Korea and overseas after transfer of technology.
“We have developed the world’s first UHD co-channel repeater technology and established high technical barriers to entry.” said Kim Heung-muk who is the head of ETRI Media Research Headquarters. “We hope that the technology will lead global markets.”
Staff Reporter Kim, Youngjoon | kyj85@etnews.com