Capacity Testing Engineer, RAN 4G/5G

Job Description

Responsibility

• Design and develop test cases and automation scripts for capacity, multi-UE, traffic mix, and call model testing of LTE/NR field scenarios using UE, EPC, and 5GC simulators. • Perform rigorous performance, regression, and system integration testing of eNB/gNB software and hardware across lab and field-like environments. • Conduct first-level analysis of control-plane and user-plane issues using UL/DL BLER statistics, Layer-2 scheduling behavior, power control, timing advance, and HARQ convergence. • Validate 3GPP 32.425 and custom KPIs/PIs, including Availability, Accessibility, Retainability, Integrity, Mobility, and Utilization metrics. • Execute capacity and stress testing with impairments applied to fronthaul, midhaul, and backhaul interfaces to assess system robustness and performance limits. • Automate capacity and performance test suites, including KPI verification and long-duration monitoring of CPU, memory, and disk utilization. • Debug and analyze field data, identify potential issues, and reproduce problems in lab environments for root cause analysis. • Utilize Kubernetes (K8s) to deploy, manage, and scale cloud-native test environments and tools, enabling efficient and repeatable test execution. • Track test execution progress and defects, perform periodic reviews, and collaborate closely with development, SAT, product, and deployment teams to drive issue resolution. • Contribute to continuous improvement of testing processes and tools, mentor junior engineers, and actively participate in knowledge sharing and best practices. • Design, develop, and maintain automation test frameworks for web services, APIs, and microservices. • Execute automated and manual test cases in Linux-based Kubernetes environments. • Validate application deployments, configurations, and behavior in Kubernetes clusters. • Perform functional, integration, regression, and smoke testing. • Automate testing for CI/CD pipelines (e.g., Jenkins, GitLab CI, GitHubActions). • Validate containerized applications using Docker and Kubernetes. • Collaborate closely with developers, DevOps, and product teams to understand requirements and identify test scenarios. • Analyze test results, log defects, track issues, and work with teams for resolution. • Perform API testing using tools/frameworks such as REST Assured, Postman, or similar. • Support performance, scalability, and reliability testing where required. • Ensure test coverage for cloud-native and microservices-based architectures. • Contribute to test documentation, test plans, and QA best practices. • Automation of functional & capacity testing of EMS, managing 4G LTE and 5G NR RAN nodes deployed on containerized platforms, covering all FCAPS domains (CM, PM, FM, Security, Access Management) • Validate south & north bound integration of EMS, ensuring reliable alarm handling, configuration delivery, performance data collection, and software management, ensuring accurate exposure of alarms, KPIs, configurations, and reports through standard interfaces. • Utilize Kubernetes for deploying, managing, and scaling complex test environments and associated tools, ensuring seamless test execution. • Collaborate closely with development, product management, and field deployment teams to clarify requirements, report defects with clear reproducibility, and verify fixes. • Contribute to the continuous improvement of testing processes, methodologies, and tools, advocating for best practices in a cloud-native environment. Requirements: • Bachelor’s or Master’s degree in Electronics & Communication, Electrical Engineering, Computer Science, Telecommunications, or a related field. • Experience of 2–6 years in Capacity and Performance testing for 4G LTE (FDD/TDD) and 5G (NSA/SA FDD/TDD) • LTE/NR Knowledge: Strong understanding of LTE/NR architecture, protocol stack (PHY, MAC, RLC, PDCP, RRC, S1AP, X2AP, GTP, SDAP), 3GPP specs, OTA concepts, and key network features (DRX, Paging, Network Slicing, CA, UL CoMP, SON, SPS, RoHC, TTIB, CG, etc.). • Testing & Tools: Hands-on experience with UE simulators (TM500, Keysight, JDSU, IXIA) for Capacity/Multi-UE testing, Mobility scenarios, VoLTE/VoNR, LTE/NR features, and Core network testing. • Test Design & Execution: Skilled in creating test cases/scripts for capacity, Near field realistic traffic mix, call models, spectral efficiency, scheduler performance, and realistic field scenarios. • Debugging & Analysis: Strong debugging skills for both control and data planes • Automation & Scripting: Proficiency in Python (test automation, framework design, API testing, data analysis) and familiarity with Java/Perl scripting. • Cloud & Tools Management: Experience with Kubernetes for test tool deployment and scalable environments; version control systems like Git; network upgrades, installations, and patches. • Traffic & Application Optimization: Familiarity with RTP/RTCP, TCP traffic optimization, and video/application layer performance enhancements. • Soft Skills: Flexible, proactive, detail-oriented, able to multi-task, work independently or collaboratively in a global team, with excellent analytical, communication, and problem-solving skills. • Professional Attitude: High commitment to delivering robust, high-quality solutions and taking initiative in fast-paced, dynamic environments.
• RAKUTEN SHUGI PRINCIPLES: Our worldwide practices describe specific behaviours that make Rakuten unique and united across the world. We expect Rakuten employees to model these 5 Shugi Principles of Success. • Always improve, always advance. Only be satisfied with complete success - Kaizen. • Be passionately professional. Take an uncompromising approach to your work and be determined to be the best. • Hypothesize - Practice - Validate - Shikumika. Use the Rakuten Cycle to success in unknown territory. • Maximize Customer Satisfaction. The greatest satisfaction for workers in a service industry is to see their customers smile. • Speed!! Speed!! Speed!! Always be conscious of time. Take charge, set clear goals, and engage your team.