Expert Details
RF IC and systems design for wireless communication
ID: 724440
Texas, USA
The active devices that he designed include buffer amplifiers, power amplifiers, low noise amplifiers, receivers, up-converters, and mixers. The operating frequency of active device is from 17 to 43 GHz. The MMICs for these devices use 0.15 ?m GaAs pHEMT (pseudomorphic High Electron Mobility Transistor) technology to accommodate such a high frequency with high performances.
Expert also design and develop transitions for microwave/millimeter wave circuits. At microwave/millimeter-wave range, the power loss is significant when transmitting the microwave power through the transmission lines. Most of the microwave or millimeter-wave systems are composed of various kinds of transmission lines such as coax, waveguide, microstrip, coplanar waveguide (CPW), coplanar stripline (CPS), slotline, and finline etc. It is because each microwave circuit or component has its own characteristic which is suitable for certain transmission line. For the low loss microwave/millimeter-wave power transmission between components and circuits with various transmission lines, transitions between dissimilar transmission lines are required. Specifically, waveguide-to-microstrip transition can be widely used in versatile applications. Expert has done a research for this transition for low transmission loss and low returned power loss. For doing this, lots of mathematical/numerical time and frequency domain analyses are performed through the computer simulation, and practical fabrication and measurement are accomplished. Several kinds of the waveguide-to-microstrip transition are currently studied, which are used for vertical and side interface between the feeding port and circuit. With the transition, circuit would be greatly simplified by reducing several steps of transitions and low loss would be achieved by the nature of waveguide.
For the interconnection between MMICs and microstrip, bonding wire is required. This boding wire produces unnecessary inductances at high frequencies, which highly degrades the microwave/millimeter-wave circuit performances. Inductance value changes significantly as frequency moves toward higher bands. To reduce the parasitic inductances, wideband impedance matching techniques need to be studied to improve the input return loss.
Another project is designing outdoor point-to-point transceiver for the frequency range of 18 to 38 GHz using surface mount MMICs. By suing surface mount devices, boding wire is not necessary at all. Surface mount technology at the frequency range from 17 to 40 GHz is a great challenge. Undesired parasitics should be minimized for packaged surface mount MMICs. Numerical analysis using computer simulation is required and realistic implementation techniques need to be investigated.
He designed Microwave/millimeter-wave antennas for communication systems from 2 to 30 GHz.
He has consulted investors by showing certain company's prospective product lines and their positions in the industry and future. That company also does GaAs RF IC industry.
He explained from short term to long term prospect of that company purely based on technology and product line. GaAs, GaN amplifiers, BAW, SAW filters, Wi-Fi products.
Education
Year | Degree | Subject | Institution |
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Year: 2002 | Degree: Ph.D | Subject: Electrical Engineering | Institution: Texas A&M University |
Year: 1998 | Degree: Master | Subject: Electrical Engineering | Institution: Texas A&M University |
Year: 1992 | Degree: B.S | Subject: Electrical & Control Engineering | Institution: Hong-Ik University |
Work History
Years | Employer | Title | Department |
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Years: 2015 to Present | Employer: Undisclosed | Title: Technical Staff | Department: Advanced RF Techniques and Systems |
Responsibilities:Responsible for research and development of RF communication systems such as receiver, transmitter and transceiver for US Defense |
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Years | Employer | Title | Department |
Years: 2013 to 2015 | Employer: RF Micro Device | Title: Staff Design Engineer | Department: Wireless Connectivity |
Responsibilities:Design and develop 2.45GHz Wi-Fi Transceiver design with GaAs HBT and pHEMT on GaAs substrate |
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Years | Employer | Title | Department |
Years: 2006 to 2012 | Employer: TriQuint Semiconductor | Title: senior design engineer | Department: RF IC design center (MMIC) |
Responsibilities:Fully responsible design/develop and released point-to-point radio and VSAT product lines.• PA design expert up to 40 GHz • Define and develop full TX and RX chain chipset for satellite communications such PA, VGA, up/down-converter, LNA • Link budget analysis for the system design • Develop and release ground breaking both die and SMT packaged compact 30GHz, 1W, 4W and 7Watt high power amplifiers for transmitter chain of the VSAT digital radio. • Develop and release ground breaking both SMT packaged compact 14GHz, 4 Watt and 7 Watt high power amplifiers for transmitter chain of the VSAT digital radio. • Develop and launch industry first fully monolithic 30 GHz, 7 Watt high power amplifiers using TriQuint GaAs pHEMT process and its packaged version. • Design 3.5GHz, 10Watt high power amplifier for WiMAX base station using TriQuint HV2(High Voltage)-pHEMT process. (IEEE802.16e) • Design and develop high power amplifiers with GaAs pHEMT technology for Ku/Ka-band VSAT digital radios and execute project leading for Ku/Ka-band product line such as amplifiers, attenuators, mixers, switches, IQ modulators (up-converter) and LNB (low noise block) for receivers. • Define system or RF components specification and proposes the chip set for customer needs. • Project managements for individual projects with tight schedule control using NPD (New Product Development) systems such as design cycle and project slippage control. |
Career Accomplishments
Associations / Societies |
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IEEE |
Publications and Patents Summary |
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He has 15 publications in distinguished journals and conferences and has one book chapter in Wiley book series. |
Additional Experience
Expert Witness Experience |
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Market trend for RF microwave semiconductor industry. Investment consulting for the industry above. Technical consulting for design and development of new products. |
Training / Seminars |
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RF IC design tutorial and seminar on 2016. |
Vendor Selection |
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He has been sourcing RF component companies such as filters, amplifiers, mixers and package companies for high frequency IC packaging from domestic suppliers to offshore assemblers. He also performed outsoucing for foundry companies for semiconductor fabrications for various process approach. |
Marketing Experience |
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As a design engineer for +15 years, he has seen historical trends for RF & microwave IC design trends and knows about new emerging markets for this industry. Growth potential for each product lines and technologies is essential for new product development. |
Other Relevant Experience |
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Technical consulting such as new product design consulting. |
Language Skills
Language | Proficiency |
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Korean | Native |
English | Expert |
Fields of Expertise
radio-frequency measurement, microwave antenna, microwave circuit, microwave circuit packaging, microwave detector, microwave communication, microwave device, microwave electronic equipment, microwave engineering, microwave filter, microwave frequency, microwave integrated circuit, microwave integrated circuit design, microwave mixer, microwave passive component, microwave power amplifier, microwave radiation, microwave research and development, microwave transmission, radio communication, radio communication circuit, radio frequency test instrumentation, radio frequency amplifier, radio frequency circuit, radio-frequency electronic equipment, radio-frequency filter, radio frequency integrated circuit, broadband radio service, custom integrated circuit, digital radio-frequency signal, cellular radio frequency link system, wireless communication, telecommunications electronics science, electronics research and development, cellular telephone, cellular telecommunication, communications technology, monolithic integrated circuit design, integrated-circuit design, cellular mobile radio, cellular communication