Measurement of radiated spurious emissions with the substitution and field strength test methods

By means of simulation software the substitution and the field strength test methods to measure radiated spurious emissions are investigated to get a better insight into their relevant advantages and disadvantages. The equipment under test (EUT) is a LCX (leaky coaxial cable) antenna driven by a signal generator; this antenna is commonly used in Wi-Fi and Bluetooth applications. The radiation patterns of the EUT and of the substitution antennas are simulated and the parameters required by the two test methods are derived. In order to comply with the applicable specifications dealing with radiated spurious emissions the EIRP and ERP together with their uncertainties are calculated.