Managing Dual Band Radio Laboratory Testing under Chinese Regulatory Frameworks
SRRC approval for dual-band radios demands locked firmware power tables, local agent coordination, and strict host radiated spur compliance to avoid re-test delays.
Power Table NVRAM Locking
Meaning
Firmware security mechanisms prevent unauthorized modifications to the calibrated RF transmission parameters of a wireless module. The implementation of power table nvram locking ensures that the configuration tables containing the transmit power limits for each channel and region are permanently secured in non-volatile random-access memory. This restriction prevents end-users or third-party software from increasing the output power beyond the limits certified during regulatory testing.
Compliance Integrity
Certification of a wireless device is based on the specific power levels configured at the factory. If these levels could be easily modified, the device’s compliance with radio frequency exposure and spurious emission limits would be compromised. Locking the power tables in non-volatile memory ensures that the device remains within its certified operating parameters throughout its lifecycle.
Hardware Protection
Chipset manufacturers implement this protection through secure boot mechanisms or write-once memory registers. During the final factory calibration, the transmission power values are written to the non-volatile memory and the write protection is enabled. Any attempt to modify these values after this lock has been applied is rejected by the system firmware.
Integration Validation
System integrators must verify that the locked power tables are correct for the target markets. This check is performed during the factory test phase to ensure that correct regional settings are active.