Principal DSP Designer - Coherent Optical Transmission Systems - Acacia

The application window is expected to close on: 10/11/2026 Meet the Team Join our high-impact team at Acacia, a Cisco company, where we design industry-leading coherent optical transceivers powering hyper-scale cloud data centers, AI infrastructure, and global telecommunication networks. We are a specialized, collaborative team of algorithm and ASIC innovators operating at the forefront of digital signal processing (DSP) and forward error correction (FEC) technology. Our team directly architects the custom silicon and complex control algorithms that push transmission speeds, energy efficiency, and reach beyond physical limits. If you are passionate about solving deep mathematical and physical layer challenges alongside world-class optical and semiconductor experts, this is the team for you. Your Impact As a Principal DSP Designer, you will serve as a senior technical authority driving the algorithmic architecture for our next-generation low-power, high-baud-rate coherent optical transceiver ASICs. You will invent, simulate, and mathematically prove novel DSP and FEC algorithms, translating breakthrough theoretical concepts into highly optimizable hardware architectures. You will partner closely with ASIC designers, electro-optic engineers, and firmware architects to model complex analog RF and non-linear optical impairments, establish precision specifications, and validate live silicon performance in the lab. Your innovations will directly define Acacia’s architectural roadmap and accelerate global data connectivity. Minimum Qualifications PhD + 8+ years of hands-on experience designing, simulating, and implementing DSP and/or FEC algorithms for high-speed optical communications or complex communication systems. Demonstrated expertise developing mathematical physical layer simulation models in both floating-point and fixed-point precision. Programming experience in C/C++, MATLAB, or Python for communication systems modeling, simulation development, and performance analysis. Experience validating, testing, and optimizing DSP/FEC algorithms on real silicon or laboratory hardware setups, correlating measured physical results with algorithmic models. Preferred Qualifications Experience collaborating directly with ASIC design and verification teams, with working familiarity in RTL (Verilog, SystemVerilog, or VHDL) and hardware micro-architecture trade-offs. In-depth knowledge of coherent optical physical layer impairments, including chromatic dispersion (CD), polarization mode dispersion (PMD), carrier phase recovery, and non-linear compensation. Demonstrated experience modeling analog front-end (AFE), RF, and electro-optical transceiver components (e.g., ADCs, DACs, laser phase noise, driver non-linearities). Proficiency working in Linux development environments with standard software engineering practices and version control systems (Git, Perforce, or SVN). Strong technical leadership and communication capabilities, with a proven track record of authoring clear architectural specifications, patent disclosures, and presenting complex technical concepts to multi-disciplinary engineering teams. Why Cisco? At Cisco, we’re revolutionizing how data and infrastructure connect and protect organizations in the AI era – and beyond. We’ve been innovating fearlessly for 40 years to create solutions that power how humans and technology work together across the physical and digital worlds. These solutions provide customers with unparalleled security, visibility, and insights across the entire digital footprint. Fueled by the depth and breadth of our technology, we experiment and create meaningful solutions. Add to that our worldwide network of doers and experts, and you’ll see that the opportunities to grow and build are limitless. We work as a team, collaborating with empathy to make really big things happen on a global scale. Because our solutions are everywhere, our impact is everywhere. We are Cisco, and our power starts with you. Message to applicants applying to work in the U.S. and/or Canada: The starting salary range posted for this position is $223,100.00 to $285,600.00 and reflects the projected salary range for new hires in this position in U.S. and/or Canada locations, not including incentive compensation*, equity, or benefits. Individual pay is determined by the candidate's hiring location, market conditions, job-related skillset, experience, qualifications, education, certifications, and/or training. The full salary range for certain locations is listed below. For locations not listed below, the recruiter can share more details about compensation for the role in your location during the hiring process. U.S. employees are offered benefits, subject to Cisco’s plan eligibility rules, which include medical, dental and vision insurance, a 401(k) plan with a Cisco matching contribution, paid parental leave, short and long-term disability coverage, and basic life insurance. Please see the Cisco careers site to discover more benefits and perks. Employees may be eligible to receive grants of Cisco restricted stock units, which vest following continued employment with Cisco for defined periods of time. U.S. employees are eligible for paid time away as described below, subject to Cisco’s policies: 10 paid holidays per full calendar year, plus 1 floating holiday for non-exempt employees 1 paid day off for employee’s birthday, paid year-end holiday shutdown, and 4 paid days off for personal wellness determined by Cisco Non-exempt employees** receive 16 days of paid vacation time per full calendar year, accrued at rate of 4.92 hours per pay period for full-time employees Exempt employees participate in Cisco’s flexible vacation time off program, which has no defined limit on how much vacation time eligible employees may use (subject to availability and some business limitations) 80 hours of sick time off provided on hire date and each January 1st thereafter, and up to 80 hours of unused sick time carried forward from one calendar year to the next Additional paid time away may be requested to deal with critical or emergency issues for family members Optional 10 paid days per full calendar year to volunteer For non-sales roles, employees are also eligible to earn annual bonuses subject to Cisco’s policies. Employees on sales plans earn performance-based incentive pay on top of their base salary, which is split between quota and non-quota components, subject to the applicable Cisco plan. For quota-based incentive pay, Cisco typically pays as follows: .75% of incentive target for each 1% of revenue attainment up to 50% of quota; 1.5% of incentive target for each 1% of attainment between 50% and 75%; 1% of incentive target for each 1% of attainment between 75% and 100%; and Once performance exceeds 100% attainment, incentive rates are at or above 1% for each 1% of attainment with no cap on incentive compensation. For non-quota-based sales performance elements such as strategic sales objectives, Cisco may pay 0% up to 125% of target. Cisco sales plans do not have a minimum threshold of performance for sales incentive compensation to be paid. The applicable full salary ranges for this position, by specific state, are listed below: New York City Metro Area: $250,600.00 - $416,900.00 Non-Metro New York state & Washington state: $241,400.00 - $371,000.00

• For quota-based sales roles on Cisco’s sales plan, the ranges provided in this posting include base pay and sales target incentive compensation combined.
• * Employees in Illinois, whether exempt or non-exempt, will participate in a unique time off program to meet local requirements.