Sr Modem Firmware Engineer

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.

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

Requirements

4+ years in embedded Linux development; 2+ years with OpenWrt or similar distributions; 2+ years integrating cellular modems; 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

Nice to have

5+ years integrating cellular modems across multiple chipset vendors (preferred); Master’s degree (preferred); experience with Qualcomm SDX-series modules; Quectel/Telit modules; ModemManager; VPN integration (WireGuard, OpenVPN, IPsec); eSIM/eUICC provisioning; multi-WAN failover (mwan3)

Benefits

Annual bonus opportunity (Short-Term Variable Compensation Plan); Subsidized nationwide PPO medical benefit options including low-deductible Point of Service Plan and qualifying High Deductible Health Plan with company-provided HSA contribution; Subsidized HMO option through Kaiser for California employees; Subsidized dental and vision coverage; 401(k) plan with 4% company match and immediate vesting; Company-paid basic life and AD&D insurance; Company-paid disability benefits; Minimum 15 days 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 paid maternity leave; 6 weeks parental/adoption leave at 100% pay; Employee Assistance Program; Mobile therapy; Volunteer paid time off