Senior Embedded Software Engineer in Cheltenham

Help Shape the Future of Advanced Navigation & Sensor-Fusion Technology. We design and manufacture advanced RF navigation and communication systems used across defence, law enforcement, and civil applications worldwide. We are globally recognised for delivering industry-leading solutions that offer exceptional performance across size, weight, power, and cost.

As our UK operation continues to grow rapidly, we are investing heavily in new engineering capability, product development, and manufacturing expansion. We are now seeking a Senior Embedded Software Engineer to play a key role within our growing UK engineering function. This is an opportunity to work on genuinely advanced positioning, navigation, and sensor-fusion systems while helping shape our future embedded software capability.

You will work closely with hardware, RF, FPGA, systems, and manufacturing teams in a highly collaborative onsite environment where ideas move quickly from concept to prototype to production.

The Opportunity

We have an expanding and rapidly growing R&D team with multiple active projects. We are looking for a Senior Embedded Software Engineer to develop and optimise Kalman filter-based navigation and sensor-fusion algorithms on microcontrollers, primarily ARM Cortex platforms and ideally STM32. You will work close to the hardware, taking ownership of critical algorithm-to-firmware implementation and delivering robust, production-grade embedded software for real-world systems operating in demanding environments.

This is a fully onsite UK role with regular interaction with international engineering teams and direct exposure to fast-moving development and production activities.

Why Us?

• Work on advanced real-world navigation and positioning technology
• Be part of a rapidly expanding UK engineering operation
• Help shape engineering standards, technical direction, and future team growth
• Collaborate closely with RF, FPGA, hardware, and manufacturing specialists
• Fast iteration cycles through direct access to onsite SMT production
• Solve highly complex embedded and real-time engineering challenges
• Gain exposure to cutting-edge RF, GNSS, and sensor-fusion technologies
• Opportunity to make a visible impact within a growing international business

What Youll Be Doing

• Implementing, tuning, and maintaining Kalman Filter pipelines including EKF, UKF, and classical KF
• Developing production-grade embedded C/C++ firmware on ARM Cortex-M platforms
• Integrating and processing data from IMUs, GNSS, magnetometers, barometers, and other navigation sensors
• Designing deterministic real-time acquisition and filtering pipelines
• Optimising computational performance and memory footprint using fixed and floating-point approaches
• Developing validation workflows including simulation replay, logging, repeatable test scenarios, and HIL environments
• Collaborating with hardware and systems engineers on calibration, timing, sensor behaviour, and interface protocols
• Supporting rapid prototyping and smooth transition into production manufacturing
• Producing high-quality technical documentation, test evidence, and engineering artefacts

To be open, honest & up-front from the start, this role, when not at client site, travelling or at exhibitions/conferences, will be fully based on-site, 5 days a week, without the remit for WFH or hybrid working.

What Were Looking For

Essential Experience

• Strong embedded software development experience using C/C++
• Commercial experience developing firmware on microcontrollers
• Proven experience implementing Kalman filtering, estimation, or sensor-fusion systems in real-world environments
• Strong understanding of:
• Real-time embedded systems and deterministic timing
• Noise modelling, sensor calibration, drift, and bias correction
• Linear algebra concepts used in filtering and estimation
• Experience with ARM Cortex-M platforms, ideally STM32
• Experience debugging embedded systems using JTAG/SWD, tracing, logic analysers, gdb, or similar tools
• Experience working with embedded communication protocols including SPI, I2C, UART, and CAN

Desirable Experience

• GNSS and inertial navigation systems
• IMU + GNSS fusion
• Attitude estimation, quaternions, DCM
• Dead reckoning, ZUPT, or inertial estimation techniques
• CMSIS / CMSIS-DSP
• FreeRTOS
• STM32CubeIDE / CubeMX
• HIL testing, Monte Carlo simulation, or recorded dataset replay
• Experience within navigation, aerospace, defence, robotics, autonomy, or advanced sensing environments

If you are looking for a role where you can work on genuinely advanced embedded systems, influence engineering direction, and make a lasting impact within a growing organisation, we would love to hear from you.