Network Engineer

Modem Chipset Lab Test Engineer

Location: [San Diego, CA] (Onsite / Lab-Based)
Business Travel: up to 5%
Job Type: Full-Time

The Opportunity

We are seeking a Modem Chipset Lab Test Engineer to support 5G/LTE and NTN (Non-Terrestrial Network)/satellite validation in controlled lab environments. You will configure test setups, execute RF and protocol testing, and analyze diagnostic logs to troubleshoot modem and device performance.

Working with R&D and carrier teams, you will validate software updates and new features, resolve technical issues, and improve reliability across cellular and satellite systems.

What You’ll Do

·        Perform RF, protocol, functional, and regression testing for 5G NR SA/NSA, LTE, and applicable legacy cellular and NTN/satellite technologies.

·        Configure and maintain cellular network simulators/callboxes, RF equipment, mobile devices, and repeatable test setups, including system integration and test configuration management.

·        Operate relevant platforms such as Rohde & Schwarz CMW500/CMX500, Keysight UXM, Anritsu MT8000A, or equivalent systems.

·        Use diagnostic and device-support tools such as QXDM/QCAT, QPST, Shannon DM, and XCAL/XCAP to support device setup, log collection, and issue analysis.

·        Troubleshoot IMS registration, VoLTE/VoNR call flows, data-session establishment, mobility, and protocol issues using diagnostic logs and applicable 3GPP specifications.

·        Develop and execute test cases from project requirements and applicable 3GPP/carrier specifications, covering software updates, new features, performance KPIs, and regression scenarios.

·        Reproduce defects in controlled lab conditions, document configurations and failure evidence, and work with R&D, QA, and carrier teams to verify fixes and track issues through closure.

What You’ll Bring (Required)

·        Bachelor’s degree in Telecommunications, Electrical Engineering, Computer Engineering, Computer Science, or a related field, or equivalent practical experience.

·        Hands-on experience in cellular lab testing, RF testing, or modem/device validation.

·        Strong understanding of 5G NR standalone (SA), non-standalone (NSA), and LTE, including voice, data, signaling, and performance testing.

·        Experience configuring lab test setups and operating at least one relevant cellular network simulator/callbox or RF test platform.

·        Experience collecting and analyzing modem diagnostic logs using QXDM/QCAT, Shannon DM, XCAL/XCAP, or equivalent tools.

·        Experience testing Android devices, validating software/modem updates, and executing test cases with defined pass/fail criteria.

·        Understanding of TCP/IP and UDP, with the ability to troubleshoot connectivity and interpret basic protocol call flows.

·        Working knowledge of NTN/satellite fundamentals, including LEO/GEO systems, propagation delay, Doppler shift, and coverage.

·        Strong troubleshooting, technical documentation, and communication skills, including the ability to reproduce issues and clearly report findings.

Nice to Have

·        Hands-on experience with 3GPP Release 17 or later NTN testing, satellite call flows, or direct-to-device satellite connectivity.

·        Advanced protocol analysis across PHY, MAC, RLC, PDCP, RRC, and NAS.

·        Advanced IMS/SIP signaling analysis and root-cause investigation of VoLTE/VoNR issues.

·        Experience with carrier acceptance/interoperability testing or GCF/PTCRB certification support.

·        Hands-on Wireshark experience for packet-level troubleshooting and performance analysis.

·        Python or shell scripting experience, plus familiarity with Android Debug Bridge (ADB) for device control, log collection, and test automation.

·        Familiarity with legacy cellular technologies (WCDMA/UMTS, GSM), GNSS/GPS, or Wi-Fi/Bluetooth coexistence testing.

Work Environment

·        Primarily onsite in a lab with controlled network and RF conditions.

·        Daily hands-on work with RF equipment, hardware setups, and mobile devices, following lab safety procedures.

·        Occasional extended hours or weekend testing based on project schedules