RF Engineer

About Kelluu We are turning the real world into a digital one, with accuracy down to the smallest detail. Imagine a near future where everything you see can be explored through data delivered by Kelluu, and where AI works continuously across that data to find what you need to know. Everything turned into answers. We’re a Finnish deep-tech company, headquartered in Joensuu with offices in Helsinki and Tampere. The team is growing fast, the goals are ambitious, and we’re hiring people who want to build something that matters. Our technology is flight-proven and operational. We’re a NATO DIANA Phase 2 alumni with several thousands of hours of autonomous BVLOS flight experience, active programmes across multiple NATO nations, and a rapidly growing team. We operate in both defence and civilian markets: the same technology that supports border security also monitors critical infrastructure and the environment. P.S. We just raised 15M€ Series A. Why this role exists Kelluu is building a new RF and radar domain from scratch to dramatically expand what our airships can sense, detect, and understand. This role exists to explore, prototype, and validate RF-based sensing concepts early — before dedicated hardware teams scale it further. What you’ll own You’ll be responsible for turning RF physics into working signal processing and detection algorithms, using real-world data and rapid prototypes. The impact you’ll have: Build and prototype RF, radar, and signal processing algorithms using existing hardware (e.g. SDRs) and real measurement data Translate RF physics and sensing theory into practical, testable software systems Develop early detection, estimation, and tracking capabilities that contribute directly to airship situational awareness Experiment, test, and iterate — shaping what RF-based sensing on an airship can realistically do Contribute to antenna and RF concept development for airship integration, in close collaboration with hardware-focused colleagues Your team You’ll work closely with Kelluu’s core airship, autonomy, and systems engineers in Joensuu. The RF domain is being built now, which means significant ownership and influence from day one. What success looks like By 3 months, you will have: A strong understanding of Kelluu’s airship platform, sensing goals, and constraints First RF or signal processing prototypes running on real data By 6 months: Demonstrated detection or estimation algorithms validated through experiments Clear direction on which RF/radar concepts are worth scaling further By 12 months: Meaningful RF-based sensing capability integrated into Kelluu’s roadmap A foundational RF algorithm stack others can build on What we’re looking for You’ll thrive here if you have: Strong fundamentals in physics or engineering (electromagnetics, signal processing, or applied mathematics), at MSc level or equivalent Solid mathematical maturity: signal processing, linear algebra, probability and statistics at university level An experimental mindset, with evidence of building, testing, and iterating on real systems Experience solving hard technical problems (thesis, research project, competition, open-source work, or comparable) Sufficient programming ability to prototype and iterate quickly, primarily in Python Genuine curiosity about radar, RF, and sensing — prior professional experience is not required Even better if you also bring: Experience with SDRs or other RF hardware Exposure to radar, RF, or wireless signal processing Familiarity with detection and estimation concepts (CFAR, Kalman filtering, hypothesis testing) Experience with clutter suppression or noise reduction techniques Knowledge of positioning concepts such as TDoA, PDoA, FDoA, or direction finding What you get The opportunity: Build a brand-new RF and sensing domain inside a growing deep-tech company Work hands-on with real systems, real data, and real flight platforms Shape the future capabilities of autonomous airships from an early stage The practicalities: Healthcare, Lunch benefit, Culture, sports, and wellbeing benefit (Epassi), Phone The tools you need to do your best work Flexible work culture — results matter more than desks The kind of place this is Kelluu is a dual-use deep-tech company at the intersection of autonomy, AI, and aerial intelligence. We build technology that serves both national security and society, and we take that responsibility seriously. We’re scaling fast, which means you’ll have real influence on how things are built. The flipside: things move quickly, priorities shift, and everyone wears a few hats. If you want a finished playbook and a clear lane, this probably isn’t the right fit. If you want to write the playbook yourself, it might be exactly right. We use AI tools extensively, not as a gimmick, but because it lets a growing team move faster than anyone expects. We expect everyone to be curious about how to work smarter. Details Location: Joensuu Start date: As soon as possible Reports to: FCS and RF Lead Systems Engineer Jaakko Rantala Due to the nature of our business in the defence and dual-use sectors, the selected candidate must successfully pass a standard security clearance. Furthermore, certain roles are subject to international export control regulations (e.g., EU Dual-Use or ITAR), which may impose specific requirements regarding the candidate’s citizenship and background. Interested? Apply by 8.8.2026. Include your CV and application. We’re less interested in a list of past job titles and more interested in your impact. What to expect: Initial call Interview with Jaakko and our Head of Software Pauli Assignment Final interview / meet the team Reference check and offer Questions? Reach out to Jaakko Rantala [email protected] or by phone on Tue-Fri between 12-14: +358 50 403 8374, please send a text message if Jaakko misses your call, or Head of Software Pauli Järviluoto ‭+358 50 542 1479‬ [email protected]. Direct applications only.