5G/4G Cellular Layer1 Control Firmware Engineer

Santa Clara Valley (Cupertino), California, United States


Role Number:200141550
Do you have a passion for invention and self-challenge? Do you thrive on pushing the limits of what’s considered feasible? As part of a world class modem team, you’ll craft sophisticated leading-edge embedded firmware that deliver more performance in our products than ever before. You’ll work across disciplines to transform improved hardware elements into a single, integrated design. Join us, and you’ll help us innovate new cellular technologies that continually outperform the previous iterations. By collaborating with other product development groups across Apple, you’ll push the industry boundaries of what wireless systems can do and improve the product experience for our customers across the world. Do you want to have an impact on every single Apple product? As a Cellular Layer 1 Firmware Engineer on this team, you will be at the center of the 5G/4G/multimode cellular firmware effort within a silicon design and firmware development group responsible for designing and productizing state-of-the-art cellular SoCs. This position requires someone comfortable will all aspects of embedded software development, that thrives in a dynamic cross-functional organization, is not afraid to debate ideas openly, and is flexible enough to pivot on constantly evolving requirements.

Key Qualifications

  • Understanding of 5G and 4G 3GPP standards, or similar Wireless standards and competent knowledge on Physical Layer control procedures.
  • Hands-on experience with L1 Software/Firmware in 2G/3G/4G/5G is a plus
  • Deep understanding of software engineering principles, and core computer science fundamentals.
  • Highly competent with C and C++ programming, solid understanding of compilers, build and source code control tools
  • Significant experience with embedded real-time programming for low latency and memory constrained applications
  • Significant experience and solid understanding and programming of cache-friendly, data-oriented objects and handles.
  • Significant experience with Real Time Operating Systems (RTOS) applications, multi-core, multi-threaded and concurrent programming.
  • Experience with ISS and NCAM, virtual platforms, silicon prototyping and emulation systems.
  • Proficiency in debugging embedded software systems.
  • Familiarity with ETM, ETB, JTAG, and any other trace and debug tools.


Specify, design, and implement a multi-mode L1 firmware architecture of a state-of-the-art mobile wireless communications system. Implement key 3GPP L1 PHY control procedures, scheduling, against low latency, on/off chip memory and energy constraints. Examples of L1 PHY Control areas include: Idle Mode Connected mode DRX Connection and mobility management Radio Resource Management Radio Link Monitoring Beam Management Multi-carrier PHY channel configuration, activation and scheduling Inter-RAT, Inter-frequency ENDC, NRDC, Multi-SIM Work with silicon designers to define processor, bus, and memory subsystems. Work with other Software designers to define interfaces to protocol stack, MAC/RRC and required processor subsystems. Assist in the development of pre-silicon emulation systems/virtual platforms and use them for pre-silicon FW design and HW verification. Evaluate and implement leading edge tools for build, formal verification and test. Define methodologies and best practices.

Education & Experience

Bachelors degree in electrical engineering or computer science or experience is required.

Additional Requirements