A gigahertz-bandwidth vector signal generation and analysis system for traveling-wave tube amplifiers testing

The calibration procedure for a vector signal system which has over 1.6 GHz of RF bandwidth is described. To achieve the desired bandwidth, two software filters (a prefilter and a postfilter) are used to correct the non-uniform frequency responses in the system. We describe techniques for obtaining the response functions of both the signal generator and the signal analyzer. The measured response functions are used to construct the filters to achieve the flat frequency response. Finally a 1-Gsymbol/s 32-QAM raised-cosine-filtered waveform is generated to demonstrate the application of the system.