A Significance Test for Reverberation- C hamber Measurement Uncertainty in Total Radiated Power of Wireless Devices
Abstract: We develop a significance test that determines whether the component of uncertainty due to the finite number of stepped mode-stirring samples or the component due to the lack of spatial uniformity dominates for a particular chamber setup and stirring sequence, as well as expressions for uncertainty for both cases. The significance test is illustrated with a measurement example comparing unloaded and loaded chambers for the measurement of a large-formfactor machine-to-machine device transmitting the wideband code-divisionmultiple-access (W-CDMA) protocol. Based on this example, we illustrate a method that allows users to estimate the minimum number of stepped modestirring samples needed to ensure that the component of uncertainty due to spatial uniformity dominates for a given chamber setup, allowing the use of a simplified expression for uncertainty.