Mitchell Lee Email & Phone Number

Plantation, Florida, United States

• Engage in full lifecycle of design and development for VHF, UHF, 7/800 MHz bands in two-way radios
• Design voltage controlled oscillators (VCOs) to generate a stable local oscillator and reference signal
• Optimize phase-locked loop (PLL) circuitry for improved stability, phase noise, spur performance, two-point modulation, lock time, etc.
• Automate test routines in LabVIEW and Python to characterize PLL performance, such as phase noise, hum and noise, harmonics, etc.
• Perform root-cause analysis on malfunctioning radios pertaining to frequency generation
• Create schematic capture and layout design in Cadence Allegro for VCO modules

Plantation, Florida, United States

• Designed, implemented, tested, and debugged two Colpitts VCOs to cover the VHF band
• Evaluated varactor diodes’ equivalent noise resistance to lower phase noise on VCOs covering the 7/800 band
• Developed an automation script for the R&S FSWP Phase Noise Analyzer and VCO Tester to measure and record frequency range, sensitivity, and power, which reduced test time by 60%
• Perform statistical analysis on VCO control voltage distribution to identify the probability of a radio failing to produce a stable carrier signal
• Created an automated test method to evaluate VCO stability and startup
• Provided input on engineering risks when selecting dual source parts

Plantation, Florida, United States

• Conducted receive and transmit microphonics testing for APX NEXT XN to ensure demodulated audio is not overpowered by parasitic “howling”
• Converted MOSFET logic circuits to a GreenPAK IC to reduce parasitic capacitance and reduce needed PCB area
• Calibrated on-board accelerometer and gyroscope using the SPI interface that allows for the “Man Down” feature on radios to be usable
• Reworked and microsoldered prototype PCBs to tune VCOs to different frequencies