Understanding DC Content & Nature of RZ & NRZ Signals

[dervast]

Hi reading a technical atricle about returtn to zero and non-return tozero pulses i have read that the Rz signals have more transitions than the NRZ and less DC content..
...an NRZ signnal appears to have a DC nature..
What Dc content and DC bature means?

 

[berkeman]

RZ and NRZ signals will have different spectra, and the "DC content" or "nature" refers to how much energy is present at DC in each of those spectra. In general, DC content is bad, since it is really not helping to transmit any information. For practical comm channel design, you would like to limit the bandwidth used to transmit the information. The tighter the bandwidth, the less expensive and less constrained the comm channel physical layer components, generally speaking.

 

[dervast]

Thx a lot but now i want to learn what really bandwitdh is.. For many years i have beedn using the term bandwith to express how faster sth is.. For example the giga bit ethernet has bigger bandwith(here i mean ability to convey data) than the 100mbit ethernet