# Signal Processing: Which statement(s) in convolution is/are correct?

i) A convolution product is always at least as long as the longer original signal.

ii) A convolution in the time domain corresponds to an autocorrelation in the frequency domain.

iii) A cross-convolution of two signals equals the convolution of both signals, where one is time-observed.

iv) If a signal is convolved with itself sufficiently often and appropriate time-scaling is applied, the result converges towards a sin function.

v) The convolution of two signals is bilinear, i.e. given is fixed second signal it is linear with the first signal and proportional to the product of the linear factors of both signals.