Sr. Firmware Engineer​/Consultant

1)
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Visa Accepted: US Citizen or Greencard only (No OPT or other visa holders)

Location: Oakbrook, IL 60523 (Onsite)

We need a hands-on firmware consultant who owns the cellular stack end to end: modem integration, RF bring-up, firmware, carrier and regulatory certification.

You will work onsite in Oak Brook alongside hardware, firmware, cloud and compliance teams to take products from prototype through certification and production.

• Design, develop and debug embedded C/C++ firmware integrating LTE-M, NB-IoT and/or LTE Cat-1/Cat-1bis modules into commercial door and lift controllers
• Integrate modems (e.g., Nordic nRF
  91, Quectel, u-blox, Telit, Sierra Wireless) via AT commands or vendor SDKs
• Implement network attach, PDP context, PSM/eDRX power saving, reconnect and fallback logic
• Build secure connectivity to the cloud: TLS/DTLS, MQTT/CoAP, device provisioning, and certificate management
• Implement and validate firmware-over-the-air (FOTA) updates for both the host MCU and the modem
• Support SIM, eSIM/eUICC and carrier profile management

• Partner with hardware engineers on antenna selection, placement and tuning inside metal commercial enclosures
• Run RF bring-up and performance testing (TRP/TIS, signal quality, coverage) using call boxes and network emulators
• Debug with spectrum analyzers, logic analyzers, modem trace tools and JTAG/SWD

• Lead the product through FCC (Part 15, 22, 24, 27), ISED, PTCRB/GCF and carrier certification (AT&T, Verizon, T-Mobile)
• Coordinate with test labs, module vendors and carriers; prepare test plans and certification documentation
• Address RF exposure, EMC and module-certification reuse requirements
• Work with product management, cloud, QA and compliance to define requirements and test strategy
• Document architecture, design decisions and test results; mentor internal engineers on cellular best practices

• 8+ years of embedded firmware development in C/C++ on 32-bit MCUs (ARM Cortex-M or similar)
• 4+ years hands-on with cellular IoT (LTE-M, NB-IoT, LTE Cat-1, or Cat-4) shipped in production products
• Deep knowledge of 3
  
  GPP LTE concepts: attach/registration, bands, PSM/eDRX, RRC states, roaming
• Direct experience taking a cellular product through PTCRB/GCF and at least one US carrier certification
• Working knowledge of FCC/ISED regulatory requirements for intentional radiators
• RTOS experience (FreeRTOS, Zephyr, ThreadX or similar)
• Comfortable with lab RF tools: call box/network emulator, spectrum analyzer, oscilloscope
• Able to work onsite in Oak Brook, IL
• Bachelor's degree in Electrical Engineering, Computer Engineering or equivalent experience

• Experience in garage door, access control, building automation, industrial IoT or other commercial connected products
• Hands-on with Nordic nRF
  91 series and the nRF Connect SDK / Zephyr
• Knowledge of LTE Cat-1bis, 5G Red Cap or 2G/3G sunset migration
• Background in antenna design or RF hardware, not just firmware
• Experience with AWS IoT, Azure IoT Hub or similar device clouds
• Familiarity with product security standards (UL 2900, ETSI EN 303 645, IEC 62443)
• Experience with UL safety requirements for motorized door operators (e.g., UL 325)

$000,000 – $000,000 Salary range is not shown on the candidate portal