Investigation of Measurement Uncertainties and Errors in a Radiated Emission Test System

Several important measurement uncertainties and errors associated with test receivers and preamplifiers in a radiated emission test system are rigorously investigated. It is found that some defective RF connectors can have abnormal insertion loss (similar to 0.8 dB in our study) at certain frequencies. Signal synchronization between the signal generator and the test receiver is found to be an important factor in cable attenuation measurements, and an uncertainty of about 0.8 dB is recorded between using and not using signal synchronization. The measurement uncertainty associated with the preamplifier gain variation is found to be as large as 0.47 Db, when the temperature changes from the room temperature (25 degrees C) to 35 degrees C or to 15 degrees C. The results obtained in this study provide additional knowledge to the existing measurement standards used in the industry. They also have important implications for practical measurements in seeking to fulfil industrial measurement standards.