Professor Heung-No Lee's research team developed a method to receive ultra-wideband radar signals quickly and accurately

□ A research team led by Professor Heung-No Lee of the School of Electrical Engineering and Computer Science at the Gwangju Institute of Science and Engineering (GIST, President Seung Hyeon Moon) has developed a new ultra-wideband signal receiver that can receive multiple broadband signals using different frequencies simultaneously without distortion at tens of GHz.

∘ The new ultra-wideband signal receiver can be used to greatly reduce the harm to allies in battlefield situations. Ultra-wideband radar receivers can be used to quickly and accurately by allied forces to identify and avoid enemy radar signals.

∘ In addition, the new ultra-wideband signal receiver can be used to secure big data, one of the essential elements of the 4th Industrial Revolution. Signal information in the ultra-high frequency range that could not be received in the past can now be digitally converted and stored as big data.

□ In the meantime, ultra-wideband signal reception problem has been regarded as a persistent problem due to signal distortion called aliasing when the receiving bandwidth is very wide compared to the performance of signal receiving hardware.

∘ American electrical engineer Harry Nyquist proposed a prevention measure in 1928 known as Nyquist to prevent aliasing by precisely removing high frequency band signals that could cause signal distortion depending on the performance of the receiving hardware. Although this method does not cause distortion, information is permanently lost in the high-frequency band. Despite this shortcoming, the Nyquist method has been used in most signal-receiving systems to date.

∘ However, to extend the receiving bandwidth of the signal receiving system to ultra-wideband, the signal distortion problem had to be solved without removing high-frequency band signals. Basically, a new method other than Nyquist was urgently needed.

□ Professor Heung-No Lee's research team solved this problem with a new approach. They deliberately extended the bandwidth to a much wider range. Although it was distorted by aliasing, it did not lose information in the high frequency band. To remove the distortion, they developed a fast mathematical algorithm to restore a clean broadband signal.

∘ Therefore, they have developed a new system that can receive ultra-wideband signals of tens of GHz without loss of information.

□ Professor Heung-No Lee said, "The research suggests a new way to solve the Nyquist dilemma that has been in use since 1928. The success of our research has greatly expanded the receiving bandwidth of the signal receiving system as well as the use of low cost hardware, making this research even more important because it can easily be implemented."

□ This research was undertaken by Professor Heung-No Lee, Jehyuk Jang, and Dr. Sanghun Im and was , and (first author) and Dr. Han Hwa System (second author) And was performed with the support from the Ministry of Defense, Industry and Energy and the Korea Development System. The research results were published online on April 9, 2018, in IEEE Transactions on Signal Processing, a well-known journal of signal processing.