Core Network Engineer, 3GPP Wireless

AST SpaceMobile is building the first and only global cellular broadband network in space to operate directly with standard, unmodified mobile devices based on our extensive IP and patent portfolio and designed for both commercial and government applications. Our engineers and space scientists are on a mission to eliminate the connectivity gaps faced by today’s five billion mobile subscribers and finally bring broadband to the billions who remain unconnected. Position Overview We are seeking a highly skilled and motivated Core Network Engineer with deep hands-on expertise in 3GPP wireless core networks (4G LTE and 5G NR). In this role, you will be responsible for the engineering, integration, configuration, and testing of our wireless core network elements and services. You will translate architectural designs into practical deployments, ensuring the network is robust, performant, secure, and compliant with 3GPP standards. This is a critical role that requires a strong problem-solving mindset and a meticulous approach to network implementation. Key Responsibilities: Engineer, implement, and deploy 3GPP core network elements, including 4G LTE EPC (MME, SGW, DRA) and 5G Standalone Core (AMF, UPF, SMF, SEPP). Work closely with Solutions Architects to translate high-level designs into detailed engineering plans and configurations. Configure core network elements, interfaces, and associated services, including S1-AP, NAS, GTP-C/U, Diameter, HTTP/2, SCTP, PFCP, and 5G service-based interfaces (N1-N15). Implement and manage virtualized (VNF) and cloud-native (CNF) network functions across OpenStack, VMware, Kubernetes, and OpenShift environments. Develop and implement automation frameworks and scripts using Python, Ansible, Terraform, and Bash to streamline deployment and operational activities. Lead integration efforts between core network elements and adjacent domains, including RAN, transport, OSS/BSS, and third-party platforms. Design, develop, and execute comprehensive test plans covering Factory Acceptance Testing (FAT), System Integration Testing (SIT), and User Acceptance Testing (UAT). Perform functional, performance, regression, interoperability, and stress testing for core network services. Identify, analyze, and resolve complex technical issues through collaboration with vendors, engineering teams, and operations organizations. Support proof-of-concepts (PoCs), field trials, and new technology evaluations. Provide expert-level support for operational incidents, including troubleshooting, root cause analysis, and corrective action planning. Monitor and analyze network KPIs to identify bottlenecks and recommend performance optimization strategies. Drive continuous improvement initiatives for deployment, integration, automation, and operational processes. Create and maintain engineering documentation, including configuration guides, Method of Procedure (MOP) documents, test plans, test reports, and as-built network diagrams. Ensure all deployments adhere to 3GPP standards, security policies, industry best practices, and internal operational guidelines. Qualifications Education: Bachelor’s or Master’s degree in Electrical Engineering, Computer Science, Telecommunications, or a related technical discipline. Experience: 10+ years of hands-on telecommunications experience with a strong focus on engineering, integration, configuration, and testing of 3GPP wireless core networks. Proven experience supporting large-scale 4G LTE EPC and/or 5G Standalone Core deployments. Extensive experience working with core network solutions from leading vendors such as Ericsson, Nokia, Samsung, or Mavenir. Strong expertise in deploying and managing virtualized and cloud-native network functions (VNF/CNF) on Kubernetes, OpenShift, OpenStack, and VMware platforms. Hands-on experience with wireless roaming configurations, Diameter signaling, and inter-PLMN connectivity. Preferred Qualifications: Experience supporting Direct-to-Device (D2D), Non-Terrestrial Networks (NTN), satellite connectivity, or emerging wireless technologies. Soft Skills: Excellent analytical, troubleshooting, and problem-solving capabilities with exceptional attention to detail. Strong verbal and written communication skills, with the ability to engage effectively across technical and non-technical teams. Ability to thrive in a fast-paced, collaborative environment while managing multiple priorities. Self-motivated, proactive, and results-oriented, with a strong sense of ownership and accountability. Demonstrated ability to work independently and drive initiatives from concept through implementation. Technology Stack: Deep knowledge of 3GPP standards for 4G LTE (Release 8-15) and 5G (Release 15-18), including core network architectures, signaling procedures, and call flows. Advanced expertise in core network protocols and interfaces, including S1-AP, NAS, GTP-C/U, Diameter, HTTP/2, SCTP, and PFCP. Strong understanding of network security principles, hardening techniques, and best practices for core network infrastructure. Proficiency with automation and scripting technologies, including Python, Ansible, Terraform, and Bash. Strong knowledge of IP networking fundamentals, routing protocols such as BGP and OSPF, and Quality of Service (QoS) mechanisms. Experience using network troubleshooting and performance monitoring tools, including Wireshark, protocol analyzers, and monitoring platforms. Familiarity with public cloud environments such as AWS, Microsoft Azure, and Google Cloud Platform (GCP), as well as cloud-native networking concepts. Physical Requirements Ability to lift up to 25 lbs. Ability to use a computer for extended periods. Ability to work in an office and lab environment, including hands-on integration and testing of core network equipment. Ability to travel occasionally to support field trials, proof-of-concepts, or cross-team integration activities as needed. This job description may not be inclusive to the duties and responsibilities listed. Additional tasks may be assigned to the employee from time to time or the scope of the job may change as needed by business demands . AST SpaceMobile is an Equal Opportunity, at will Employer; employment is governed on the basis of merit, competence and qualifications and will not be influenced in any manner by race, color, religion, gender, national origin/ethnicity, veteran status, disability status, age, sexual orientation, gender identity, marital status, mental or physical disability or any other legally protected status.