Coherent Optical System Architect – Infinera – Sunnyvale, CA

Brief Description

Infinera is looking for a coherent optical system architect to join the Optical System Group in Sunnyvale, CA.


Infinera is seeking a Coherent Optical System Architect to join our Optical Systems Group (OSG). The engineer will be responsible for characterizing the performance of Infinera’s next-generation coherent photonic integrated circuits (PICs). The ideal candidate will be prepared to work with early prototype line cards to get an initial look at product performance and provide rapid feedback to the PIC team. Performance characterization will include bandwidth measurements, OSNR tolerance, laser linewidth, and common-mode rejection ratio. OSG works closely with many parts of the company, and the candidate should anticipate frequent interactions with the coherent ASIC team on coherent signal processing issues and ADC/DAC ENOB, with optical, ASIC, and systems engineering teams. A key component of this role is the ability to understand and make tradeoffs between optical, electrical, and digital capabilities in order to optimize the overall system performance.


Infinera’s next generation communications platform will be defined, developed, characterized, and optimized on your optical testbed. Your experimental data will fuel our design, starting with off-the-shelf components, evolving to prototype PICs, and eventually taking the form of the final integrated line card. This requires ownership of the optical design, optimization methods, and stabilization techniques. One particular component of your research will be pushing our optical systems to higher baud rates.

Frequently used diagnosis capturing coherent waveforms on a high-speed oscilloscope and performing coherent signal processing on waveforms, and measuring bit-error rate performance in the presence of optical noise and other impairments. Of particular interest will be pushing to faster baud rates.

Through frequent interaction with the firmware team, you will assist in optimizing performance-critical aspects such as power-up self-calibration, receive acquisition, real-time performance monitoring, and in-service performance optimization. These algorithms will be tested during the implementation stage to ensure they operate properly.

Results will be presented internally and documented as electrical and optical performance specifications for next-generation platforms.

Some customer-facing interactions may be required, such as field trials using prototype equipment, or debugging unusual field failures that cannot be resolved through the normal customer service process.


PhD. in Electrical Engineering or Applied Physics with minimum of 3 years of industrial experience in optical communications, photonics, high speed electronics or systems. Will consider Master’s degree with 5+ years of applicable experience.

Fundamental understanding of optical communication systems, DWDM transmission systems, photonic integrated components, electronic (integrated) circuits, and signal analysis and processing.

Hands-on experience working with system-level optical communication hardware and components.

Extensive understanding of coherent communications systems, including experience with QPSK, 16QAM, and 64QAM, as well as coding and forward error correction algorithms.

Experience characterizing high-speed RF and mm-wave interconnects, amplifiers, and components.

Characterization of RF/mm-wave systems, such as S parameter measurements, jitter measurements, and ADC/DAC performance and ENOB

Hands-on experience with high-speed optical and electrical test, and measurement equipment control and data acquisition.

Programming experience in Matlab, Python,, or C desired.


Infinera is an equal opportunity employer. All qualified applicants will receive consideration for employment without regard to race, religion, color, national origin, sex, age, status as a protected veteran, or status as a qualified individual with disability. EEO Employer/Vet/Disabled.

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