Senior Embedded / RF Engineer to $6000

We are looking for a highly skilled Embedded RF Engineer with practical experience in developing and modifying ExpressLRS (ELRS). You will design and enhance radio communication systems, develop custom firmware features, work with RF protocols, and create new capabilities for RC/FPV hardware.

Key Responsibilities

RF & Firmware Development

• Develop and update ELRS firmware for transmitters, receivers, and accessories (e.g., backpack modules, VRX controllers).
• Work with RF chipsets (LoRa, SX127x, SX1280).
• Add new protocol features such as separate TX/RX keys, improved bind options, and adjustable bind rate.
• Support extended frequency ranges within hardware limits.
• Improve link quality, stability, and packet processing.

System Architecture

• Design firmware architecture for custom ELRS features.
• Implement Diversity, Gemini, and other multi-channel RF modes.
• Work with interfaces like SPI, I²C, UART, DMA, and GPIO.

Hardware Interaction

• Cooperate with hardware engineers to tune RF paths, antennas, and PCB layouts.
• Test RF modules using tools like spectrum analysers, VNAs, and SDRs.

Testing & Debugging

• Create and run tests for ELRS functionality.
• Troubleshoot issues across different protocol layers.
• Measure latency, packet loss, and overall link performance.

Required Skills & Experience

3+ years of experience in embedded C/C++ development (STM32, ESP32, or similar MCUs)

Experience with microcontrollers such as STM32, ESP32 or similar

Hands-on experience with RF modules (LoRa/SX127x) and understanding of FHSS/PRNG principles for hopping.

Familiarity with Linux / embedded Linux (OpenWRT, Buildroot) and working with GStreamer / ffmpeg for streaming applications.

Technical English - Intermediate+ (reading documentation, working with upstream projects).

Preferred Qualifications

Experience developing for OpenIPC or working with camera SoCs.

Background in creating MSP/CRSF/Telemetry integrations for flight controllers.

Practical experience in RF link testing (spectrum, BER/RSSI analysis).

Experience with libsodium, mbedTLS, or OpenSSL on embedded systems.