Modem System Test Engineer - Wireless Technologies and Ecosystems |

Apple

2d

About The Position

The Modem System Test Engineer will join the Wireless Technologies and Eco-Systems (WTE) team to validate multi-radio platforms and ensure seamless concurrent operation between cellular technologies, including LTE and 5G NR FR1/FR2, and adjacent radios such as Wi-Fi, Bluetooth, Ultra-Wideband (UWB), and GNSS. The role focuses on wireless coexistence (COEX) and addresses cross-radio interference, receiver desense, and protocol arbitration challenges.

The position is responsible for end-to-end system testing, performance characterization, and failure triage of cellular baseband and multi-radio coexistence features. It bridges baseband protocol software, RF hardware, and connectivity systems to assess real-world performance under interference conditions. The engineer uses trace analysis, lab simulation, RF instrumentation, and automation to investigate performance degradation, desense mechanisms, and protocol timing collisions. The role works cross-functionally with system architecture, firmware, protocol development, RF design, and carrier engineering to expand test coverage, identify root causes, and influence system-level mitigation designs.

Requirements

• Bachelor’s or Master’s degree in Electrical Engineering, Computer Engineering, Telecommunications, or a related field.
• Deep technical understanding of 3GPP LTE and 5G NR (Rel-15/16+) across Layer 1 (PHY), Layer 2 (MAC/RLC/PDCP), and Layer 3 (RRC/NAS).
• Strong grasp of RF transceiver architectures, in-device coexistence (IDC), antenna isolation, harmonics, intermodulation distortion (IMD), receiver desense, and multi-radio interference mitigation techniques.
• Proven system test, integration, or validation experience using commercial wireless network emulators such as Keysight, Rohde & Schwarz, or Anritsu, and RF instrumentation such as spectrum analyzers, signal generators, and power meters.
• Strong proficiency in Python for test automation, instrument control (SCPI/VISA), and automated parsing and analysis of large log datasets.
• Demonstrated ability to triage and root-cause multi-layer failures across hardware, firmware, and protocol interactions.

Nice To Haves

• Experience testing Dual-SIM / Dual-Active (DSDS/DSDA) or complex cellular scenarios with simultaneous connectivity radios.
• Working knowledge of 3GPP in-device coexistence specifications, including Rel-11+ IDC mechanisms, autonomous denial, and auxiliary information reporting.
• Experience with non-cellular wireless standards such as Wi-Fi 6/6E/7 (802.11ax/be), Bluetooth 5.x, UWB, NFC, and GNSS.
• Familiarity with data analysis and visualization libraries such as Pandas, NumPy, Plotly, or Matplotlib for large-scale test KPI dashboards.
• Contributions to 3GPP standardization (RAN4, RAN5) or carrier certification testing for coexistence and performance.
• Proficiency in diagnosing complex system-level issues through lab or field experimentation, analytics, and log analysis.
• Excellent analytical and critical-thinking skills.
• Excellent communication and interpersonal skills.

Responsibilities

• Perform end-to-end system testing, performance characterization, and failure triage of cellular baseband and multi-radio coexistence features.
• Validate concurrent operation between cellular technologies and adjacent radios.
• Analyze traces and use lab simulation, RF instrumentation, and automation to investigate performance degradation, receiver desense, and protocol timing collisions.
• Drive test coverage and root-cause complex issues across hardware, firmware, and protocol interactions.
• Work with system architecture, firmware, protocol development, RF design, and carrier engineering teams.
• Influence system-level mitigation designs.

What This Job Offers

• Job Type: Full-time