YZhai

YAJUN ZHAI

310-***-****

Los Angeles, CA **066 *************@*****.***

EDUCATION

University of Maryland, College Park, MD May, 2004

Master: Electrical and Computer Engineering

Chinese Academy of Space Technologies(CAST)

Master: Electrical Engineering

Beijing University

BS: Radio and Electronics

SKILLS

Computer simulation and programming skills (Embedded Software, RTOS, winCE, WinMobile, C/C++, MATLAB, assembly), algorithm analysis and design.

Spread spectrum communication, GPS, AGPS.

Wireless communication, CDMA.

System integration, strong debugging skills.

DSP, GPS signal processing, Microprocessor system. ClearCase

EXPERIENCE

Telenav (WinCE, WinMobile,GPS, AGPS, Visual Studio 2005) Nov, 2008 – present

Senior software engineer

Took charge of new ACE(Address capture/Address search Engine) design for new GPS project

Starting from requirement analysis, within one and half months, finished requirement analysis, ACE design document, Index design, API design for

 Country select, state search,

 Within a country or state, City center search by name and by zipcode,

 Within a country or state, Enter City (Name or Zipcode) first, then enter street, then enter street number

 Within a state, Enter a street first, then enter a city, then enter street number

 Within a state, Enter a street first, then enter cross street.

Finished program implement for

 Country select, state search

 City center search by name and by zipcode,

 Enter City (Name or Zipcode) first, then enter street, then enter street number

 Helped QA to setup test project, provided test sample code.

AC Design provided some index design solutions, analyzed performance, including time, SD card and memory usage.

All AC design provides candidate list, smart speller, provides next letters when gets current input, and provide street number range and first number for street number input.

Transferred to Verizon wireless project since this project is urgent.

Within one week, found problem and provide solution for a AGPS bug unsolved for long time.

Added new features, such as show and change C-server IP address when enter secret code in several screen.

Magellan GPS(GPS, embedded SW, winCE, C/C++) Nov, 2006- Aug, 2008 Senior firmware engineer

 Responsible for dynamic, multi tasks, worked with several groups.

 Completed SW development to decode and show fix/location, satellites information, TTFF information and compare performance between different GPS chipsets by decoding NMEA/Sirf binary protocol output and encode/send command to chipsets to control them.

 Individually finished first application SW based on platform, which can show map, routing, guardians and navigation info, and can do simulation.

 Developed required features, functions. Debugged platform software.

 First run Ariel GPS SW successfully in winCE unit, fixed building errors, solved white main screen problem, fixed map shift problem, corrected configuration errors, corrected project setting errors and corrected COM port (GPS chipset) parameters.

 Solved many critical bugs(crashes, memory leaks, missed information, failure functions) in UI, platform components and third party SW in winCE(for third party’s problems, pointed out the problems, gave them solution suggestion and let them solve them).

 Debugged some performance bottlenecks and fixed them. Reduced over 50% time in application start up and map drawing.

 Responsible for merging SW from different groups, fixed compiling/linking errors, maintained build to make sure it’s ok after each update/merge/check in. Solved bugs happened after merge/check in. Cleaned workspace, removed unused codes/files.

 Participated in code reviews of own or neighboring projects.

 UI Chinese and map security implementation. Prepared training document for customers and engineers in Beijing office.

Nokia (CDMA, GPS, AGPS, system integration, software design, RTOS)

Design Engineer July, 2004—Oct, 2006

 Design locationing(GPS) capabilities into CDMA handsets at system and protocol level

 Responsible for integration of hardware and software in the lab environment once product and/or engine design has begun.

 Interface to all disciplines (GPS, MCU, DSP, RF, Location server) to define the product at the system level to meet performance and product requirements.

 Perform debugging on software and hardware, make sure program follows GPS protocol and IS801.

 Perform design and requirement document reviews.

 Develop GPS system test method and procedure .Design and maintain GPS testing and post processing software. Provide test report and problem analysis for GPS functional and performance.

Comsearch,a company of Andrew Corporation (IS 95, CDMA2000-1x, GSM)

Senior Engineer August 2001-July 2002

• Wireless communication theory and experience.

• CDMA/GSM/GPRS network design and optimization.

• Strong ability to solve the GSM/GPRS/CDMA RF problem.

• Optimization presentation for the employee of Comsearch.

• GSM/GPRS optimization for AT&T Wireless in Hackensack, NJ; Chicago,IL; San Diego,CA; Buffalo, NY.

• Provided report about CDMA/GSM network optimization procedure.

• Network database checking, parameter adjusting.

• Answered the customer question about GSM/GPRS.

Lucent Technologies (IS95, CDMA2000-1x, GSM, Wireless communication)

Senior Engineer, team leader 3 years

Beijing, China

• Wireless communication theory and experience.

• Managed CDMA 2000-1x network design/optimization in one province.

• Parameter adjusting, capacity, coverage analysis, database checking.

• CDMA/GSM training to employees.

• Gave Unicom Customers training about CDMA/GSM.

• Application software development for design tools.

• Start-up GSM RF group member in Lucent Technologies in China.

• As a team leader, finished GSM network RF Design and optimization in four

provinces.

• RF design and frequency planning, traffic, capacity planning and analysis,

frequency hopping, dual band, power control.

• Interference analysis, trouble shooting, parameters adjusting.

• OMC PMS reports analysis for optimization and operation.

• Developed good relationship with Chinese Unicom Customer.

Chinese Academy of Space Technologies (CAST)

(Spread Spectrum communication, GPS, DSP, Circuit design, Microprocessor system, Logic Analyzer)

Two years

Beijing, China

Hardware Design Engineer

• Start-up engineer in GPS R&D group.

GPS C/A code acquisition and tracking loop design in digital GPS receiver.

Digital signal processing, board level circuit design.

• As one of four kernel members, finished the technical design of GPS receiver simulator using in satellite, took charge of interface and part of software design.

• As team leader, finished the design, construction and testing of VSAT satellite communication network in two provinces for Chinese Shenzhen Stock Exchange.

• Worked with experts of Russia Institute of Space Navigation about GLONASS for CAST.

• Training to new employees.

PROJECTS

1.GPS C/A code acquisition and tracking loop design in digital GPS receiver.

Digital signal processing, board level circuit design. Microprocessor subsystem, used TMS320C series high speed processor to control NCO, shift register and code generator. Used Oscilloscopes and Logic Analyzers to debug and solve the problem.

2.Filter bank design and Sub-band Coding for Digital Audio (Advanced DSP)

DSP. Made perfect reconstruction filter bank, sub-band coding. Developed a MP-3 audio coding program.

3.Linear Prediction, Synthesis, and Spectrum Estimation (Advanced DSP)

DSP. Speech compression. Built a linear predictive model for the speech signal. Developed a coding scheme. Estimated spectral of the speech signal.

4. Technology mapping using dynamic programming (CAD of Digital Systems)

Constructed a subject graph for the input circuit and find a minimum cost cover with the given set of pattern graphs.

5.Algorithm of Vertex Elimination on Graph (Mathematical Foundations for Computer Engineering)

Algorithm design and analysis. Analyzed and Implemented the algorithm of Perfect Ordering, Minimal Ordering and Fill-In on graph.

6.Mowing Robot Simulation (Software Design and Implementation)

Computer simulation. Designed a program to simulate a mowing robot working around a house.

7.Communication System Simulation(Communication Engineering)

FEC coding, Turbo coding/decoding for communication.

8.High Speed Class AB Voltage-Current Convertor With Improved Accuracy(Electrical Network Theory)

Analyzed and implemented Voltage-Current Convertors(VCCS) in the monolithic operational amplifier system design. Pspice simulation, performance comparison between conventional VCCS and high-speed bipolar VCCS circuit with improved accuracy.

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