Modem Systems Test Engineer (Wireless Coexistence)

Quick Facts

• Focus: Modem systems testing for wireless coexistence (COEX)

• Scope: Concurrent LTE/5G NR with Wi‑Fi, Bluetooth, UWB, and GNSS

• Core work: Test design, RF/protocol root-cause analysis, mitigation validation, and automation

Description

Join the Wireless Technologies and Eco-Systems (WTE) team to validate advanced cellular modem and multi-radio coexistence features. You will bridge baseband protocol software, RF hardware, and connectivity systems to ensure robust real-world performance under hostile interference conditions.

Responsibilities

• Define, develop, and execute coexistence test plans for in-device coexistence (IDC), inter-radio arbitration, multi-SIM/multi-active scenarios, and concurrent multi-band operation.

• Perform root-cause analysis using baseband protocol traces (PHY, MAC, RLC, PDCP, RRC), air-interface captures, and RF measurements to diagnose desense, throughput degradation, scheduling conflicts, dropped calls, and handover anomalies.

• Evaluate and validate dynamic coexistence mitigations (power back-off, TDM/FDM filtering, antenna switching/sharing, adaptive link management).

• Build scalable Python test automation and post-processing analytics for KPI aggregation (BLER, throughput, latency) and anomaly detection.

• Set up and maintain lab testbeds using cellular network emulators, RF matrix switches, combiners, spectrum analyzers, and wireless channel emulators.

• Collaborate cross-functionally with system architecture, firmware, protocol development, RF design, and carrier engineering to reproduce defects, validate fixes, and verify 3GPP/internal specifications.

Requirements

• Bachelor’s or Master’s degree in Electrical Engineering, Computer Engineering, Telecommunications, or related field

• Deep technical understanding of 3GPP LTE and 5G NR (Rel-15/16+) across PHY, MAC/RLC/PDCP, and RRC/NAS

• Strong RF fundamentals and coexistence knowledge (IDC, antenna isolation, harmonics, IMD, receiver desense, multi-radio interference mitigation)

• Hands-on validation experience using commercial wireless network emulators and RF instrumentation

• Strong proficiency in Python for test automation, instrument control (SCPI/VISA), and automated parsing/analysis of large log datasets

• Ability to triage and root-cause multi-layer failures across hardware, firmware, and protocol interactions

Benefits

Opportunity to validate wireless innovations that impact millions of users worldwide.