Alan JoContinuous time signal, Discrete time signal
both can have complex values
The similarity between signals and functions is particularly useful in understanding and working with the unit impulse and the unit step signal
Time signals
Engineering property
- instantaneous power means squared function, average energy means (integral of power) / time
- If the total energy is finite, the average power must be zero
- If the average power is non-zero, the total energy is infinite.