Difference between single-tone and multi-tone excitations in RF channel measurement

For inspecting on the nonlinearity of RF channel, measurements with novel multi-tone excitations are developed based on a vector network analyzer (VNA) and a multi-tone generator. Many differences have been found in both statistical averages and variances of the transmission function. These differences between statistical averages reflect the nonlinearity of RF channel, and the differences between variances suggest multitone excitation for a proper choice when a time-varying characteristic is of importance. Improvement of the excitations for nowadays channel measurement is discussed in the end.