Senior RF Design Engineer Wappenham, Northamptonshire | Hybrid Working (3 days onsite, 2 WFH) | Competitive Salary Benefits About My Client My client is a globally recognized UK defense technology leader with 45 years of innovation in advanced communications systems, long-range data links, and mission-critical RF solutions. Their systems support military and security operations in over 100 countries worldwide. They're expanding their engineering team to develop next-generation products for defense, aerospace, and battlespace communications markets. The Opportunity An exciting opportunity for a Senior RF Design Engineer to join a small, dynamic team designing world-class RF systems. You'll own full-lifecycle RF circuit design—from architecture and simulation through PCB development, testing, and production support. This is hands-on, technical RF engineering on cutting-edge defense technologies in a fast-paced but rewarding environment. Key Responsibilities RF Circuit Design: * Design high-power wideband RF amplifiers (up to 200W) using GaN/LDMOS technology * Develop RF filters, LNAs, upconverters, downconverters, and RF frontends * Transmitter/receiver circuit design and antenna development * RF system architecture and electromagnetic simulation * PCB schematic capture, layout, and component creation using Altium Designer Technical Leadership: * Lead and contribute to design reviews (PDR, IDR, CDR) * Verify designs against specifications * Troubleshoot hardware/system issues across the business * Mentor junior engineers assigned to your projects * Collaborate with multidisciplinary engineering teams * Manage external design partners when required * Support manufacturing and production as needed Essential Requirements Must Have (5 years minimum): * Proven RF circuit design experience (not just layout or systems-level work) * High-power RF amplifier design using GaN, LDMOS, or similar technologies * RF filter design from concept to implementation * Transmitter/receiver circuit design experience * LNA, upconverter, downconverter design expertise * Proficiency with PCB design software (Altium preferred) * Experience with RF simulation tools (AWR Microwave Office, Ansys HFSS, or similar) * Strong analog and digital electronics knowledge * Hands-on experience with RF test equipment (VNAs, spectrum analyzers, oscilloscopes) * British Citizen or ability to obtain SC security clearance * Degree in Engineering or equivalent work experience