Host Level Radiated Spurious Emission Pre Scan Chamber Verification Protocol
Host level pre scan verification systematically isolates host radiated spurious noise before accredited certification testing to prevent market entry delays.
Duty Cycle Correction Factor
Meaning
Calculated adjustments applied to peak emissions measurements compensate for the pulsed nature of periodic signals in compliance assessments. When a transmitter operates intermittently, the duty cycle correction factor reduces the measured peak field strength to represent the average emission level. This factor is necessary for demonstrating compliance with regulatory limits that are based on average limits.
Pulse Adjustment
Transmitter on-times are measured over a reference interval of one hundred milliseconds to calculate the duty cycle. The duty cycle correction factor is derived by taking twenty times the log of the duty cycle. This correction allows pulsed transmitters to meet average limit requirements that continuous transmitters would fail.
Compliance Margin
Certification bodies require a documented duty cycle plot from an oscilloscope showing the pulse train. This plot establishes the baseline calculation and must be included in the final test report.
Measurement Standard
Regulatory bodies like the Federal Communications Commission define the parameters for duty cycle assessments. The product’s software must be locked during testing to ensure the duty cycle does not exceed the certified limit in normal operation. If a firmware update changes the transmission pattern, the correction factor must be recalculated.
This calculation is a required part of the product’s compliance file.