pulse function

[newton1]

why we should use the pulse function in function generator when we need to check the speed of electromagnetic wave in coaxial line ??
why we can't use the other like sawtooth function??

[turin]

It is easier to compare the edges of pulse functions than to compare slanted edges. Assuming an ideal pulse, and no dispersion, the edges of the pulses will occur entirely at an exact instant in time. Using a signal with slanted edges, you would have to determine what part of the edge of the transmitted signal to compare to what part of the edge of the received signal.