Railway 5G Core Architect – FRMCS Transformation

Atos SE; Warszawa; Hybrid; PLN 90,000 - 130,000; Full time

Job summary

Atos SE in Warszawa, Poland is seeking an experienced Telecommunications Architect to support a strategic railway programme focusing on 5G Core, FRMCS, and GSM-R migration. This hybrid role involves designing core integration concepts and guiding technical decision-making with vendors.

The role requires deep knowledge of 5G Core, MCX, and FRMCS specifications, plus strong analytical skills to prepare specifications and run tender processes. Polish (native) and English (B1) are required.

Qualifications

• 3+ years in Core Network and/or MCX.
• 2+ years creating technical and analytical documentation.
• Hands-on experience gathering and analysing business and technical requirements.
• Experience developing tender documentation / Terms of Reference (OPZ).

Responsibilities

• Design implementation and integration concepts for Core 5G and MCX (with IWF).
• Analyse requirements and define architecture for FRMCS systems.
• Prepare technical specifications and tender documentation (OPZ) for 5G, MCX, and GSM-R/FDS integration.
• Evaluate available 5G market solutions and platforms.
• Develop a migration strategy from GSM-R to FRMCS.
• Lead technical consultations with manufacturers and solution vendors.
• Support market consultation processes and target technology selection.

Skills

Core Network

MCX

Documentation

Requirements gathering

Job description

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Telecommunications Architect - 5G / FRMCS

Publication Date: Jul 8, 2026

Ref. No: 549382

Location:

Warszawa, PL

Atos Group is a global leader in digital transformation with c. 56,000 employees and annual revenue of c. €7.2 billion (at the go-forward perimeter), operating in 54 countries under two brands - Atos for services and Eviden for products and systems. European number one in cybersecurity and a leader in cloud, Atos Group is committed to a secure and decarbonized future and provides tailored AI-powered, end-to-end solutions for all industries. Atos Group is the brand under which Atos SE (Societas Europaea) operates. Atos SE listed on Euronext Paris.

The purpose of Atos Group is to help design the future of the information space. Its expertise and services support the development of knowledge, education and research in a multicultural approach and contribute to the development of scientific and technological excellence. Across the world, the Group enables its customers and employees, and members of societies at large to live, work and develop sustainably, in a safe and secure information space.

Telecommunications Architect – 5G / FRMCS

About the Role
We are looking for an experienced Telecommunications Architect to support a strategic programme for a major railway client. The project focuses on 5G Core implementation and the transformation from GSM-R to FRMCS — a mission-critical initiative shaping the future of railway communications.

• Work model: Hybrid – alternating schedule (1 week on-site at client premises / 1 week remote)
• Cooperation model: B2B contract

What You'll Be Doing

• Design implementation and integration concepts for Core 5G and MCX (with IWF)
• Analyse requirements and define architecture for future FRMCS systems
• Prepare technical specifications and tender documentation (OPZ) for 5G, MCX, and GSM-R/FDS integration
• Evaluate available 5G market solutions and platforms
• Develop a migration strategy from GSM-R to FRMCS
• Lead technical consultations with manufacturers and solution vendors
• Support market consultation processes and target technology selection

What We're Looking For

• 3+ years in Core Network and/or MCX
• 2+ years creating technical and analytical documentation
• Hands-on experience in gathering and analysing business and technical requirements
• Experience developing tender documentation / Terms of Reference (OPZ)

Technical Knowledge

• Strong knowledge of 5G Core architecture and solutions
• Practical knowledge of MCX systems and IWF
• Familiarity with 5G solution architecture and configuration
• Understanding of LTE and 5G network fundamentals
• Knowledge of 5G market products and platforms
• Knowledge of current GSM-R and FRMCS specifications
• Ability to design integration between Core 5G, MCX, GSM-R, and FRMCS environments

Languages

• Polish – C2 / native (required)
• English – minimum B1 (documentation reading and vendor collaboration)

Nice to Have

• Knowledge of currently operating GSM-R and FDS system architecture
• Experience in operator / telecommunications projects
• Background in designing complex, mission-critical telecommunications systems
• Experience collaborating with telecommunications solution manufacturers

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