Senior RAN & Core Network Test Engineer

Job Title: Network Test Engineer (RAN/Core, LTE/5G)
Location: Bristol / Hybrid 
Type: Permanent

About the Role

Qualitest is looking for an experienced Network Test Engineer to join our growing team, working on cutting-edge projects with a focus on LTE/VoLTE and 5G technologies. This is an exciting opportunity to work with a global leader in telecom innovation, performing end-to-end testing, integration, and troubleshooting across RAN and Core network components.

Key Responsibilities

• Design, develop, and execute comprehensive test cases for integration, regression, and system validation across 2G, 3G, LTE, and 5G networks.

• Perform functional, performance, and regression testing on EPC and IMS Core components, including VoLTE and Mission Critical Services.

• Analyse logs and traces (UE, RAN, and Core) to identify issues and perform detailed Root Cause Analysis (RCA).

• Work closely with cross-functional teams, including network engineers and vendors, to troubleshoot and resolve complex network issues.

• Document test results, generate reports, and manage defects using tools like HP ALM and JIRA.

Technical Expertise

• Strong knowledge of 4G/5G Core and RAN architectures, including IMS, EPC, and VoLTE call flows.

• Proficient in protocols such as SIP, Diameter, GTP, S1AP, SCTP, IPSEC, and RRC/RLC layers.

• Hands-on experience with vRAN, small cells, MIMO, GPS/PTP timing, and OpenRAN integration (RU/DU/CU).

• Skilled in using tools like Wireshark, QXDM, XCAL, Viavi, Ixia, and vendor-specific platforms (NetAct, ENM, Huawei U2020).

• Familiarity with network emulators, Python scripting, and OpenStack for automation and test environment management.

• In-depth understanding of 3GPP standards, KPIs, and performance metrics for LTE and 5G systems.

What We’re Looking For

• 8+ years of experience in network testing with a strong background in RAN technologies.

• 5+ years of hands-on experience in RAN testing (essential).

• Excellent problem-solving and communication skills, with the ability to work in a fast-paced, collaborative environment.