Research
Research Highlights
Undergraduate Student Seungjun Lee Awarded the 2023 IEEE MTT-S Undergraduate Scholarship
: Only up to 12 undergraduate scholarships are awarded worldwide each year
: He will be honored by IEEE MTT-S in June 2024 in Washington DC.
: Research Topic - Generalized similarity transformations for coupling matrices of arbitrary topologies
Graduate Student Jongheun Lee Won First Place in Student Design Competition
: 2023 IEEE MTT-S Int. Microwave Symposium, San Diego, CA
: Reflectionless Highpass Filter Design For Load-Pull Measurement Setups
: Low loss and Wide Upper Passband
: Reflectionless Response Over Wide Frequency Range
Undergraduate Student (Junior)
Seungjun Lee's Paper Published in IEEE Transactions on Microwave Theory and Techniques
: Synthesis of N-Foster-Section Filter With Maximum 2N Prescribed Transmission Zeros by Heuristic-Aided Graph Search
Reflectionless Dual-Passband Waveguide Filter
: Accurate Synthesis (Zero Reflection At All
Frequencies)
: Arbitrary Cutoff Frequencies
: Two Passbands
: Measured Reflectionsless Response Over
Entire WR-42 Band ( 18-26.5 GHz)
Electroformed Seamless Waveguide Filter
: PIM (Passive Intermodulation)-Free
: No Tuning Screws
: Corrugated LPF + Dual-Mode BPF
: No Rounded Corners in Resonators
: X-Band Satellite Communications
: Dual-Mode Technique
: Transmission Zeros
Graduate Student Jongheun Lee Won First Place in Student and Young Engineer Design Competition
: APMC 2022, Yokohama, Japan
: Passive Track
: 22 Participants
: Small-size low-loss high-rejection BPF design
US Patent
: Reflectionless Filter
: Universal Topology
: Single Layer
: Arbitrary Transmission Response
: No Reflection From DC to Infinity
Ultra-Narrowband Cavity Filter
: 0.17 % Bandwidth
: S-band
: Dual-Mode Technique
Terahertz Reflectionless Filter
: f0 ~ 275 GHz
: S11<-10 dB over 220 - 330 GHz (WR-3.4)
: Fabrication by Milling
Millimeter-Wave SIW Filter
: f0 ~ 38.8 GHz
: Single Substrate
: Surface Mountable
: Transmission Zeros
Tunable LTCC Filter
: Bandstop Response
: Attenuation > 60 dB at f0
: No Reflection in Stopband
: Frequency Tuning (1.6 : 1)
: Resonator Q ~ 2
Current Research Areas
Multi-Function Microwave Circuits
Reconfigurable and Miniaturized Microwave Filters
High-Dielectric Ceramic Waveguide Filters
K-Band Cavity Filters for Satellite Applications
Wireless Power Transfer Systems
Microwave Circuits for Next-Generation Radar Systems
Past Research Areas and Research Interests
Microwave Equipment for Satellite Applications
Dual-Mode Waveguide Filters
Group-Delay Equalizers
Self-Equalizer Filters
Input Demultiplexer (Circulator Chain Structure)
Output Multiplexer (Manifold Structure)
Radar Systems and Components
Frequency-Modulated Continuous-Wave Radar
Phase-Locked Loop Circuits