We can draw the following conclusions from the preceding discussion. In general,
any digital waveform will have infinite bandwidth. If we attempt to transmit this waveform
as a signal over any medium, the transmission system will limit the bandwidth that
can be transmitted. Furthermore, for any given medium, the greater the bandwidth
transmitted, the greater the cost.Thus, on the one hand, economic and practical reasons
dictate that digital information be approximated by a signal of limited bandwidth. On
the other hand, limiting the bandwidth creates distortions, which makes the task of
interpreting the received signal more difficult. The more limited the bandwidth, the
greater the distortion, and the greater the potential for error by the receiver.