Senior Embedded Software Engineer – RFIO / RF Systems Integration

We’re looking for humble geniuses who believe engineering can turn the impossible into reality—and who are driven to design, build, and test solutions that matter for some of the world’s most trusted companies. If you want to do meaningful work with a diverse team that believes in shared wins, continuous learning, and engineering a brighter future, this is the place for you.  We are seeking an experienced Embedded Software Engineer to develop and integrate software that controls, calibrates, and interfaces with RF transmit/receive systems. This hands-on role combines C/C++, Python, RF hardware, FPGA/firmware, and laboratory testing to characterize system performance, develop calibration and compensation techniques, and troubleshoot complex hardware/software issues. Location: Phoenix, Arizona.  On-site preferred, 3+ days/week Citizenship: U.S. Person   Key Responsibilities Develop and maintain RFIO software interfacing embedded software/FPGA with RF subsystem hardware. Develop C/C++ software to configure, control, monitor, and characterize RF and mixed-signal devices. Implement multi-channel transmitter control, including phase alignment, beamforming, power/gain leveling, and programmable RF components. Develop receiver calibration and compensation techniques for gain, phase, sensitivity, temperature, and other RF variations. Integrate RF hardware with FPGA/firmware, embedded software, and system-level components. Interpret device datasheets and develop low-level register/configuration interfaces. Develop Python test and automation for laboratory equipment, RF testing, data collection, and analysis. Perform hands-on laboratory integration, characterization, measurement, troubleshooting, and debugging. Diagnose cross-domain issues involving software, FPGA/firmware, RF, and hardware. Work across RF, FPGA, hardware, systems, and software teams to resolve technical issues. Follow disciplined software processes for requirements, traceability, verification, validation, configuration management, and documentation. Required Qualifications 5–15 years of relevant engineering experience in embedded software and hardware/software integration. Strong C and C++ development skills. Experience developing embedded or FPGA-facing software interfacing directly with RF or mixed-signal hardware. Practical understanding of RF transmit/receive signal chains, including phase, gain, synchronization, power leveling, sensitivity, calibration, and temperature compensation. Experience configuring hardware through low-level interfaces and device registers and interpreting component datasheets. Strong Python skills for test automation, instrumentation, data collection, and engineering analysis. Experience debugging issues across software, FPGA/firmware, and hardware. Hands-on experience with oscilloscopes, spectrum analyzers, network analyzers, and RF/electronic test equipment. Strong mathematical and analytical skills related to calibration, signal behavior, and system characterization. Ability to independently troubleshoot and drive root-cause resolution in a laboratory environment. Experience with requirements, traceability, verification, and validation processes. Experience with multi-channel RF systems, phased arrays, beamforming, radar, communications, electronic warfare, or similar RF-intensive systems. Familiarity with DO-178B/C or comparable requirements-based software development and verification. Must meet U.S. Person requirements. Preferred Qualifications Experience developing multi-channel RF calibration algorithms. Experience characterizing RF performance across temperature or other environmental conditions. Experience automating RF laboratory equipment using Python. Experience with SPI, I²C, UART, GPIO, or similar device-control interfaces. Familiarity with FPGA-based architectures and software-to-FPGA interfaces. Aerospace, defense, or other high-reliability embedded product experience. Experience supporting formal integration, verification, qualification, or certification activities. The QDSS Advantage  At QDSS, our advantage is purpose-driven work, collaborative teams, and complex challenges that push boundaries and build lasting impact. You’ll grow your career while contributing to mission-critical programs that demand excellence and shape the future.   What You’ll Find Here   Work That Matters – Next-generation, safety- and mission-critical projects where your contributions have real-world impact.   Growth That’s Supported – Competitive compensation, employer-matched 401(k), certification assistance, and clear opportunities for advancement.   A Culture That Works – A flexible, collaborative, and people-first environment where teamwork, innovation, and balance are valued.   Benefits Include   Competitive pay, comprehensive medical/dental/life and disability coverage, 401(k) with employer match, professional development support, and a flexible, friendly workplace.    Full compensation package is based on candidate experience and certificationsPay Ranges$127,000—$167,000 USDAt Quest Defense Systems and Solutions, we don’t just build technology — we engineer the future. From next-generation aerospace solutions to cutting-edge defense systems, we tackle the toughest, mission-critical challenges that keep people safe and push the boundaries of innovation. This is where problem-solvers, innovators, and visionary thinkers come together to shape the future. With over 25 years of aerospace and defense engineering expertise, our commitment to delivering high-quality, transformative solutions sets us apart — not just as an industry leader, but as a driving force for impactful change. Together, we’re not just leading the industry — we’re revolutionizing it.   Quest Defense provides equal employment opportunities to all employees and applicants for employment and prohibits discrimination and harassment of any type without regard to race, color, religion, age, sex, national origin, disability status, genetics, protected veteran status, sexual orientation, gender identity or expression, or any other characteristic protected by federal, state or local laws. This policy applies to all terms and conditions of employment, including recruiting, hiring, placement, promotion, termination, layoff, recall, transfer, leaves of absence, compensation and training.The physical demands described here are representative of those that must be met by an employee to successfully perform the essential functions of this job. Reasonable accommodations may be made to enable individuals with disabilities to perform the essential functions.