Modem System Test Engineer — 5G & AI-Driven Debugging

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

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.