Sr Modem Firmware Engineer

Responsibilities

• Integrate 5G modem modules into OpenWrt-based router and gateway platforms
• Develop and maintain kernel drivers for modem communication interfaces such as USB and PCIe
• Implement and optimize QMI, RMNET, and AT command interfaces for modem control
• Configure network interfaces, routing policies, and failover mechanisms
• Implement connection management daemons for automatic reconnection and band selection
• Integrate SMS, GPS/GNSS, and voice functionality where applicable
• Optimize data throughput and reduce latency across modem interfaces
• Perform modem firmware updates (FOTA) and version management
• Debug connectivity issues across the full stack, including RF, baseband, driver, and user-space
• Collaborate with hardware teams on antenna design validation and RF performance
• Create integration documentation and developer guides

Requirements

• 4+ years of experience in embedded Linux development
• 2+ years of experience with OpenWrt or similar distributions
• 2+ years of experience integrating cellular modems
• Strong expertise in Linux kernel development, including driver development, device tree, and kernel modules
• Proficiency in C/C++ programming for embedded Linux systems
• Bachelor's degree in Electrical Engineering, Computer Engineering, Computer Science, or a related field

Preferred Qualifications

• Experience with Qualcomm SDX-series modules
• Experience with Quectel or Telit modules
• Familiarity with ModemManager
• Experience with VPN integration (WireGuard, OpenVPN, IPsec)
• Experience with eSIM/eUICC provisioning or multi-WAN failover (mwan3)
• Master's degree in a related technical field

Benefits

• Competitive salary and annual bonus opportunities
• Comprehensive medical, dental, and vision coverage
• 401(k) plan with a 4% company match and immediate vesting
• Paid maternity leave (up to 16 weeks) and parental/adoption leave (6 weeks)
• Generous paid time off, including vacation, personal days, and sick time

About the Company

Ericsson is a global leader in telecommunications technology, driving innovation to solve the world's toughest connectivity challenges. We foster a diverse environment of innovators dedicated to pushing the boundaries of what is possible in 5G and beyond.