RF Circuits and Wireless Communications Systems Expert

Expertise

• RF power amplifiers and transmitters; RF Circuits and Systems for cellular, wireless.
• Power electronics (Power management).
• Analog circuits.
• Semiconductor devices.
• Electrical and electronic engineering.

RF Power Amplifier Design

• Architectures: High power output stages, full TX chain, and integrated RF front end.
• Form factors: Pallet (open and shielded), module (fully enclosed).
• Up to 20GHz. and 3kW.
• Bandwidths: Decade or greater.
• Modes of operation: Class A, Class AB/B, Class C, Class D, Class E, and Class F.
• RF Device technologies: LDMOS, GaN HEMT, GaAs FET/HEMT/pHEMT/HBT.

Linear Transmitter Architectures

• Doherty RF Power Amplifiers.
• Outphasing transmitters.
• Pre-distortion (closed loop RF).
• Control features: RF output blanking (enable/disable), EMI filtering, gain/power control (external/automatic), temperature compensation (open/closed loop), and telemetry.
• Protection and filtering: DC input protection, RF input and output protection, over temperature shutdown, bias sequencing, EMI filtering
• Control Interfaces: TTL/CMOS logic, I2C, USB, etc.

DC Power Management and Design

• ON/OFF to a complete power management system with several levels of voltage conversion and inversion, protection circuitry, noise and EMI filtering.
• RF design concepts; specified RF power amplifier design or as a stand-alone module for virtually any electronic or electrical apparatus.
• Switching DC-DC: Buck, Boost, Buck-Boost.
• Under and over voltage lockout (UVLO/OVLO).
• In-rush, total current limiting.
• Reverse polarity, ESD, lighting protection.
• Noise and EMI filtering.
• Bias sequencing.
• LED Drivers.
• Low Drop Out (LDO) Linear.

Expert Witness Experience

• California Superior Court: Civil litigation, testifying expert.
• International Trade Commission: Consulting (Subject Matter Expert).
• U.S. District Court.

Experience

Undisclosed Company, Principal and Owner, 2012 - Present

Expert Witness

• Patent litigation - Technical Due Diligence
• Civil litigation

Design Consulting Projects

• Ku-band SSPA, C-band SSPA
• Ultra high efficiency wireless charging
• High speed LTCC optical communications module
• Ultra compact high efficiency load adaptable power amplifier
• Design Consultant - DARPA MIS superconductor fabrication program

New Business and Patent Support

• Served numerous international and domestic clients, from Fortune 100 companies to startup/venture organizations.
• Patent technical analysis.
• Analysis of prior art, and claims.
• Infringement contention charts.
• Claim construction.
• Expert witness reports.
• Reverse engineering.
• Deposition.
• Expert Testimony.

Mercury Systems, Inc., Chelmsford, MA, Technical Director, 2013 - 2014

• Full profit and loss responsibility for Mercury's $2.5 million RF power amplifier business unit.
• Responsible for engineering, sales, operations, manufacturing, and test.
• Developed new business opportunities through direct customer engagement and proposals.
• Led and managed new product development and sustaining engineering.
• Managed development and production, material planning, product testing.

University of Colorado, Boulder, CO, Professor, 2013 - 2016

• Course Instructor, ECEN3250 (Microlectronics).
• Ph.D. committee member.

Honors & Publications

Languages

• Korean (Conversational)

Academic and Professional Affiliations

• Institute of Electrical and Electronics Engineers-IEEE Member

Publications

• Author and Co-Author of publications in peer reviewed journals

Education

• Ph.D. Electrical and Computer Engineering, University of California, Santa Barbara, CA
• B.A. Physics, University of California, Berkeley, CA