Senior 5G Modem Firmware Engineer (OpenWrt/Embedded Linux)

Ericsson GmbH; San Diego (CA); On-site; USD 191,000 - 239,000; Full time

Benefits offered by this job

401(k) plan with company match

Health insurance and HDHP/HSA options

Generous paid time off and holidays

Parental leave and family benefits

Job summary

Ericsson Inc. is seeking a Senior Modem Firmware Engineer in the USA to design, develop, and integrate cellular modem modules into OpenWrt-based platforms.

You will own the end-to-end modem stack—from kernel drivers to user-space daemons and network configuration—to deliver reliable connectivity and high throughput across 5G networks. The role requires deep expertise in embedded Linux, OpenWrt, and cellular modem integration, with hands-on work on QMI/RMNET/AT command interfaces and

Qualifications

• 4+ years in embedded Linux development
• 2+ years with OpenWrt or similar distributions
• 2+ years integrating cellular modems (5+ years preferred)
• Linux kernel development incl. drivers and device tree

Responsibilities

• Integrate 5G modem modules into OpenWrt-based platforms
• Develop and maintain kernel drivers for modem interfaces (USB, PCIe)
• Implement and optimize QMI/RMNET/AT interfaces for modem control
• Configure networking, routing, and failover mechanisms
• Develop connection management daemons for auto-reconnect and band selection
• Integrate SMS, GPS/GNSS, and voice features where applicable
• Optimize throughput and reduce latency across modem interfaces
• Perform modem firmware updates and version management
• Debug connectivity across RF, baseband, driver and user-space
• Collaborate with hardware teams on RF validation and antenna design
• Prepare integration docs and developer guides

Skills

Embedded Linux

OpenWrt/LEDE

Cellular modem integration

Linux kernel development

C/C++ programming

USB/PCIe drivers

QMI RMNET AT commands

Cross-compilation toolchains

Education

Bachelor’s degree in EE/CE/CS

Master’s degree preferred

Job description

Ericsson Inc. is seeking a Senior Modem Firmware Engineer in the USA to design, develop, and integrate cellular modem modules into OpenWrt-based platforms.

You will own the end-to-end modem stack—from kernel drivers to user-space daemons and network configuration—to deliver reliable connectivity and high throughput across 5G networks. The role requires deep expertise in embedded Linux, OpenWrt, and cellular modem integration, with hands-on work on QMI/RMNET/AT command interfaces and