Modem System Test Engineer - Wireless Technologies and Ecosystems

Apple Inc.; Sunnyvale, Northern (CA, KY); Hybrid; USD 129,000 - 225,000; Full time

Job summary

Apple Inc. in Sunnyvale, CA, is seeking a Modem System Test Engineer for Wireless Technologies and Ecosystems to drive 5G NR/3GPP protocol testing and baseband integration.

The role requires hands-on tests, diagnostics, and test automation across PHY/MAC layers, with collaboration across firmware, platform architecture, and RF teams. The position emphasizes robust, scalable system testing for iPhone cellular performance worldwide.

Qualifications

• Master’s degree in Electrical Engineering, Computer Engineering, Telecommunications, Computer Science, or related field.
• Deep understanding of 3GPP LTE and 5G NR specifications across PHY/MAC/RLC/PDCP/SDAP/RRC/NAS and end-to-end cellular architecture.
• Hands-on experience implementing, debugging, or validating cellular protocol stacks or physical-layer modules using commercial test equipment or open-source wireless testbeds.
• Strong proficiency in Python for test automation, data processing, and log parsing.
• Solid grasp of digital communication principles, modulation, OFDM, and channel coding schemes.

Responsibilities

• Define, develop, and execute system-level test plans exercising 5G NR (FR1 & FR2) and emerging standards across protocol control/user planes and physical-layer performance.
• Analyze protocol traces, air-interface captures, and diagnostic logs to debug complex failure modes and throughput bottlenecks.
• Build scalable test automation and leverage ML/data-driven methods to automate anomaly detection, KPI trend analysis, and failure triage.
• Partner with baseband firmware, protocol software, platform architecture, and RF hardware teams to reproduce issues, validate fixes, and ensure 3GPP conformance.
• Contribute to internal test infrastructure, test case development, and evaluation platforms spanning SDR/open-source protocol testbeds.

Skills

Python

5G NR

LTE

Test automation

Debugging

Education

Master’s degree in Electrical/Computer Engineering

Tools

SDR

Commercial test equipment

Open-source wireless testbeds

Job description

Modem System Test Engineer - Wireless Technologies and Ecosystems

Sunnyvale, California, United States Software and Services

Join the Wireless Technologies and Eco-Systems (WTE) organization and drive innovation that matters! We build and seamlessly integrate technologies that enrich peoples' lives and deliver the best user-experience. We are looking for a highly reciprocal individual who can excel in a high-paced environment. Be ready to make something extraordinary when you come here. Dynamic, encouraging people and innovative, industry-defining technologies are the norm at Apple. If you're passionate about building technology that will make a difference, we may have the job for you!

Description

We expect you to be hands-on relying upon diagnostics, analytics, crowd sourced information, lab/field experimentations as well as code/architecture review to exploit the opportunities for improvement and work multi-functionally with platform architecture, standardization, firmware/protocol development, system test & carrier engineering teams to drive the enhancement proposals and baseband optimizations. You will be required to develop advanced system evaluation and debugging capabilities. Our members enjoy the flexibility to be involved in all aspects of Protocol software - PHY, RF, SIM, NAS, AS, IP, TCP/UDP and iOS interfaces, to ensure the most robust and customer friendly software. If you are passionate about cellular technologies, want to make an impact and have the desire to work on groundbreaking cellular technologies, then we are looking for you. As part of this team you'll be impacting iPhone user experience in 100+ countries by engaging in continuous process improvements for a well tested and robust software.

Responsibilities

• Test Design & Execution: Define, develop, and execute system-level test plans exercising 5G NR (FR1 & FR2/mmWave) and emerging standards across protocol control/user planes (L1/L2/L3) and physical-layer performance
• Root-Cause Analysis: Analyze protocol traces, air-interface captures, and diagnostic logs (RRC, NAS, PDCP, RLC, MAC, PHY) to debug complex failure modes, throughput bottlenecks, and interoperability issues
• Intelligent Test Automation: Build scalable test automation and leverage machine learning/data-driven methods to automate anomaly detection, KPI trend analysis, and failure triage across large test sets
• Cross-Functional Collaboration: Partner with baseband firmware, protocol software, platform architecture, and RF hardware teams to reproduce issues, validate bug fixes, and ensure 3GPP conformance
• Testbed & Tooling Development: Contribute to internal test infrastructure, test case development, and evaluation platforms spanning both commercial test equipment and software-defined radio (SDR) / open-source protocol testbeds

Minimum Qualifications

• Education: Master’s degree in Electrical Engineering, Computer Engineering, Telecommunications, Computer Science, or a related field
• Protocol & Systems Knowledge: Deep understanding of 3GPP LTE and 5G NR specifications across the protocol stack (PHY, MAC, RLC, PDCP, SDAP, RRC, NAS) and end-to-end cellular architecture
• Hands-on Implementation or Validation: Hands-on experience implementing, debugging, or validating cellular protocol stacks or physical-layer modules using commercial test equipment or open‑source wireless testbeds
• Scripting & Automation: Strong proficiency in Python for test automation, data processing, and log parsing
• Physical Layer Fundamentals: Solid grasp of digital communication principles, modulation, OFDM, and channel coding schemes

Preferred Qualifications

• Applied AI/ML in Wireless: Experience applying machine learning frameworks (PyTorch, TensorFlow) to wireless communications problems (e.g., intelligent scheduling, link adaptation, neural decoders, or automated log anomaly detection).
• Standards & Pre-Standard Research: Familiarity with 3GPP standardization workflows (RAN1, RAN2, RAN4 or RAN5) or research contributions in beyond-5G/6G physical and MAC layer architectures
• Lab Instrumentation: Exposure to wireless test equipment (call boxes, network emulators, spectrum analyzers) or RF interface protocols

At Apple, base pay is one part of our total compensation package and is determined within a range. This provides the opportunity to progress as you grow and develop within a role. The base pay range for this role is between $129,300 and $225,300, and your base pay will depend on your skills, qualifications, experience, and location.

Apple employees also have the opportunity to become an Apple shareholder through participation in Apple’s discretionary employee stock programs. Apple employees are eligible for discretionary restricted stock unit awards, and can purchase Apple stock at a discount if voluntarily participating in Apple’s Employee Stock Purchase Plan. You’ll also receive benefits including: Comprehensive medical and dental coverage, retirement benefits, a range of discounted products and free services, and for formal education related to advancing your career at Apple, reimbursement for certain educational expenses — including tuition. Additionally, this role might be eligible for discretionary bonuses or commission payments as well as relocation. Learn more about Apple Benefits

Note: Apple benefit, compensation and employee stock programs are subject to eligibility requirements and other terms of the applicable plan or program.

Apple is an equal opportunity employer that is committed to inclusion and diversity. We seek to promote equal opportunity for all applicants without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, disability, Veteran status, or other legally protected characteristics. Learn more about your EEO rights as an applicant

At Apple, we believe accessibility is a fundamental human right. You’ll find that idea reflected in everything here — in our culture, our benefits and our digital tools. By welcoming as many perspectives as possible, we help you build a career where you feel like you belong.

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Apple accepts applications to this posting on an ongoing basis.