Determining Federal Permissive Change Thresholds for Transceiver Software Updates
Software updates altering RF output power, occupied bandwidth, duty cycle, or band limits exceed Class I limits and demand Class II or Class III filings.
Transceiver Firmware Update
Meaning
Embedded software operations modify the operational code of a radio transceiver to improve performance or adjust operational parameters. Executing a transceiver firmware update allows the manufacturer to change the radio frequency settings and power levels of the wireless module after deployment. This process must be carefully controlled to ensure that the device does not operate outside of its certified parameters.
Upgrade Mechanism
Module programming requires loading a new binary file into the non-volatile memory of the wireless module. This can be done locally or remotely over the air. System software must verify the file integrity.
Compliance Maintenance
Manufacturers must ensure that any update to the transceiver’s operational code does not invalidate its regulatory certifications. If the update modifies the output power or operating frequency bands, a re-evaluation of compliance may be required. This requires a structured process for tracking software versions and their impact on regulatory filings.
Verification Step
Developers must perform regression testing after the software is updated to confirm that the radio continues to meet all technical requirements. These tests are performed using automated test benches to verify power levels and spurious emissions. This ensures that the system’s performance remains consistent with the certified design.