Time domain analysis of frequency domain measurements

摘要

In some cases it is interesting to study the performance of a transmission channel in time domain. In this paper a method is described for using frequency domain measurements to generate eye pattern diagrams. The transition function is measured using a network analyzer. Even theoretical transmission channels can be used analytically calculated or simulated. The transition function is transformed into an impulse response in time domain using DFT. By convoluting the impulse response with the input signal, the output signal can be studied. Using these eye pattern diagrams the degeneration of the signal can be studied, it is also possible to study the improvement that can be made using different coding techniques. Crosstalk can be transformed into time domain using the same method. A simplified model to visualize the crosstalk impact on the signal is presented.