Sr Modem Firmware Engineer

Ericsson•San Diego, CA

5d•$191,000 - $239,000•Onsite

About The Position

Join Ericsson as a Senior Modem Firmware Engineer based in the USA, where you will design, develop, and integrate cellular modem modules into OpenWrt-based platforms. You will own the end-to-end modem stack — spanning kernel drivers, user-space daemons, and network configuration — to deliver reliable connectivity, seamless failover, and optimal throughput across 5G cellular networks.

Requirements

4+ years in embedded Linux development; 2+ years with OpenWrt or similar distributions
2+ years integrating cellular modems (preferred: 5+ years across multiple chipset vendors)
Linux kernel development: driver development, device tree, kernel modules
OpenWrt/LEDE build system and package development
Cellular modem integration: QMI, RMNET, AT commands
USB/PCIe modem interface drivers
C/C++ programming for embedded Linux systems
Cross-compilation toolchains and embedded build systems
Bachelor’s degree in Electrical Engineering, Computer Engineering, Computer Science, or related field (Master’s preferred)

Nice To Haves

experience with Qualcomm SDX-series modules, Quectel/Telit modules, ModemManager, VPN integration (WireGuard, OpenVPN, IPsec), eSIM/eUICC provisioning, or multi-WAN failover (mwan3)

Responsibilities

Integrate 5G modem modules into OpenWrt-based router and gateway platforms
Develop and maintain kernel drivers for modem communication interfaces (USB, PCIe)
Implement and optimize QMI/RMNET/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 (RF, baseband, driver, user-space)
Collaborate with hardware teams on antenna design validation and RF performance
Create integration documentation and developer guides

Benefits

subsidized, nationwide PPO medical benefit options including a low-deductible Point of Service Plan and a qualifying High Deductible Health Plan (HDHP), with a generous company-provided HSA contribution
For California employees, we offer a subsidized HMO option through Kaiser.
subsidized dental and vision coverage
401(k) plan has a 4% company match and immediate vesting
company-paid employee basic life and AD&D insurance
company-paid disability benefits
15 days of accrued vacation
up to 3 personal days per year
11 annual holidays
8 hours of volunteer time
80 hours of sick time annually
up to 16 weeks of paid maternity leave
6 weeks of parental or adoption leave at 100% of pay
comprehensive Employee Assistance Program
mobile therapy
volunteer paid time off