Patent ID: 8093911

Claim:
A method comprising: transmitting an input waveform into a lossy transmission medium; capturing the input waveform that is transmitted into the lossy transmission medium; capturing an output waveform from the lossy transmission medium, wherein the output waveform is produced from the lossy transmission medium in response to said transmitting the input waveform into the lossy transmission medium; determining a transfer function for the lossy transmission medium based on the captured input waveform and the captured output waveform, wherein the transfer function characterizes a linear-system model for an input-output relationship between the captured input waveform and the captured output waveform; computing a simulated response signal from the linear-system model using the transfer function and a simulated input signal, wherein the simulated input signal includes a positive exponential waveform in its leading edge, wherein the positive exponential waveform conforms to the expression A+D*exp(αt), where A is a real constant, where D is a real constant, where α is a positive real constant, where t is time, wherein at least a portion of the same positive exponential waveform occurs within a leading edge of the simulated response signal, wherein the frequency bandwidth of the input waveform is larger than the frequency bandwidth of the simulated input signal; determining a time delay between the simulated input signal and the simulated response signal.