Ray W. Email & Phone Number

Escondido, Ca, Us

Carlsbad, California, United States

Design, prototype, and bring to production military communications systems. Primary focus has been on direct conversion receivers enabling broad band performance. Performing design and analysis with a variety of analysis tools such as ADS, MATLAB, Python, Mathematica, and Excel. Using these tools to evaluate approaches and architectures to meet performance requirements such as Noise Figure, linearity (IMD, Cross-modulation), P1dB, SINAD, Output Power, ACLR/ACP, Error Vector Magnitude. Finalizing designs to meet performance requirements over process and temperature. Working with CAD team to create PWBs to achieve desired performance. Testing designs in the lab with RF test equipment such as Vector network analyzers, spectrum/signal analyzers, signal and arbitrary waveform generators, noise sources, power meters to ensure performance requirements and margins are met.

Carlsbad, California, United States

Senior RF Engineer Design, review, test and produce military communications systems. Using simulation tools including ADS, Genesys, and modeling tools such as MATLAB, Python, Mathematica, and Excel, I design and or evaluate receiver, and transmitter performance (gain, NF, C/N, SINAD, linearity IIP3, P1dB, Output power, ACLR/spectral regrowth, harmonics) to ensure requirements are achieved (RF to bits) with margin. Once prototypes are available, I create tests using standard RF test equipment (VNA, spectrum/signal analyzers, power meter, noise source) to perform initial evaluation, DVT, and ATP. Measured results are reviewed with our team and design changes are made to achieve system requirements with sufficient margin to ensure compliant in-field performance as well as yields in production. • Simulate transceiver performance RF to bits (ADS, MATLAB, Python, Excel) • Create Python, excel/VBA based Monte Carlo analysis to evaluate performance over process (truncated and asymmetric distributions), and temperature, to predict real world performance and yields. • Review PWB layout, using standard CAD tools, to provide layout guidance to improve RF losses, reduce undesired coupling, and ensure performance of RF components meet requirements. • Create MATLAB, Python based tools to evaluate test data to set test limits, improve calibration methods, and assist in debugging failures. • Write test programs in Python to test receiver and transmitter performance. These programs control and record data from test equipment and DUT. MATLAB and Python are used to analyze and plot measured data.

San Diego

Designed, and reviewed the transceiver portion of LeEco cellular phone projects in North America. Oversaw RF performance of North American cellular products. Worked with antenna design team to ensure radiated performance (TRP, TIS, ECC) met carrier requirements. • Working with PWB design team, I made adjustments to PWB layout to reduce ohmic loss, improve matching, and reduce undesired coupling. • Created spreadsheets to predict sensitivity, linearity, TX output power and linearity (spectral regrowth, harmonics) for various technologies (e.g. GSM, WCDMA, LTE). • Developed next generation designs to support forward looking 4G features, such as 4 CA (carrier aggregation), higher order MIMO, and UL CA.

San Diego

Designed Qualcomm’s Antenna Tuner evaluation system used by Qualcomm customers. Created system level guidance to meet carrier requirements e.g. B12 + B4 third harmonic de-sense, carrier aggregation support and varying bodying loading conditions. Using ADS, created accurate RF models of switching and capacitive networks. Provided support for OEM product launches, and resource planning. Guided customer support projects and managed a team of several engineers, supporting variety of RF products. Provided guidance to OEMs with respect to link budgets, and frontend design consideration. Resolved customer issues working with cross-functional teams, and devised best solutions for altering software, customer design, manufacturing or test methods as needed. Optimized customers RF radiated performance to meet carrier requirements by: • Evaluation of antenna system performance (TIS, TRP, ECC) and impedance matching • Provided recommended changes to layout, antenna design, and circuit design Provided technical support to early adopters of Qualcomm’s simultaneous voice and data dual-transmit solutions (2 uplinks active simultaneously), and providing training on requirements of RF front end (linearity and receiver de-sense, addressed issues with mechanical design (passive intermodulation considerations), and antenna design issues such as antenna to antenna isolation.

Greater San Diego Area

Evaluated and developed frequency agile components for use in commercial handsets. Led engineers and technicians in testing and implementing solutions for cellular phones, using various software tools, such as MATLAB, Excel, Mathematica, ADS and Eagleware. Designed adaptive system solutions for mobile devices, using frequency agile components. • Improved quality of evaluation results by utilizing automated tests, gathering linearity (cross modulation, IIP3 based on triple beat), reactance with respect to voltage, temperature, and time data for evaluating various components. • Developed and evaluated next generation transceiver solutions by collaborating with ASIC vendors, determining performance, cost, schedule, and size of each chipset solution from various vendors. Designed and tested prototypes using existing phone platforms, ensuring results reviewed based on both internal requirements and industry standards, IS-95/98, IS-2000. Resolved technical issues in production devices, such as improving margin in code domain performance, PCS single tone de-sense.

Greater San Diego Area

Starting in the subscriber group (later to be called the handset group) I worked on Qualcomm's first generation handset designs. Prototyping ASIC emulators of the IF/baseband sections I built and tested the emulator to meet system requirements. Additional I worked on the antenna design for the first 3 generations of Qualcomm handsets.

San Diego, Ca

I worked in the military communications group, on radio design. These were the low frequency IF portions of the radios using state of the art amplifier and filter designs. Filter design techniques included norton transformations, and standard filter tables to create the desired shape, input, and output impedances. Analysis tools included Spice, Touchstone. Additionally I wrote a cascaded chain analysis tools in Fortran 77 and basic.