Senior Access Layer Engineer

Senior Access Layer Engineer Aim high, go beyond! At Open Cosmos we are solving the world’s biggest challenges from space, providing businesses, governments and researchers access to more readily available information than ever before - ready for the challenge? Then read on… The Satcom team is responsible for the design, delivery and performance of Open Cosmos’ satellite communications services, spanning the space segment, ground infrastructure and global connectivity. As the team continues to scale we are now looking for a Senior Access Layer Engineer who’ll lead the implementation and validation of the satellite air interface, translating high-level architecture into detailed designs, simulations, and working prototypes. What will you be doing? You’ll play a key role in shaping how waveform generation, MAC protocols, and link adaptation perform within demanding LEO environments by: Developing and optimising PHY and MAC layer functionality for satellite communication systems Defining and validating random access, scheduling, timing advance, and resource allocation mechanisms Designing algorithms to mitigate LEO-specific challenges including Doppler effects, latency, and mobility constraints Building and maintaining link-level simulation environments using MATLAB, Simulink, or Python Supporting waveform, numerology, and frame structure definition aligned to 3GPP NTN and DVB-S2X standards Developing and validating link adaptation strategies including ACM and CSI-driven optimisation Defining and governing interface specifications across critical access layer subsystems Leading rapid prototyping activities using SDR platforms and system-in-the-loop validation environments Designing and executing verification scenarios for mobility, handover, BER, and throughput performance Working closely with architects and multidisciplinary engineering teams to bridge system design and implementation What You’ll bring Strong capability in wireless PHY and MAC layer design within satellite or high-performance communication systems Deep understanding of L1/L2 protocols including random access, scheduling, timing advance, and resource allocation Strong knowledge of 3GPP NR standards (TS 38.211–38.321) and familiarity with DVB-S2X Advanced modelling and simulation capability using MATLAB, Simulink, or Python Strong grounding in Digital Signal Processing including synchronisation, forward error correction, and multi-user detection Knowledge of waveform design, numerology, and frame structure validation Strong understanding of link adaptation techniques including ACM and CSI-driven optimisation Familiarity with SDR platforms such as USRP or GNU Radio and rapid prototyping workflows Understanding of LEO satellite communication challenges including Doppler, propagation delay, and mobility management A highly analytical and structured approach to problem-solving, performance optimisation, and system validation This role will be based in any of our locations. To apply, you must have the legal right to work in your chosen location. When applying, please submit your CV in English. Why Open Cosmos? Work at the cutting edge of space technology with customers around the globe A mission-driven company making space accessible to help solve real-world challenges A diverse, ambitious, and supportive team Division CRO Department SATCOM (Broadband and Narrowband) Locations Harwell, UK, Athens, Greece, Barcelona, Spain, Porto, Portugal Remote status Hybrid Employment type Full-time About Open Cosmos Open Cosmos is dedicated to solving customer problems with insights from space. Whether this is monitoring agricultural yields, assessing the damage of oil spills or providing navigation solutions, we believe that data from satellites is the most effective and sustainable way of achieving this.