NRZ (Non-return-to-zero)
NRZ line code is a binary code in which ones an zeros are represented by a significant condition and no netural or rest condition. It’s often used in Signal Processing .
Variants
| Code name | Complete name | Description |
|---|---|---|
| NRZ(L) | Non-return-to-zero level | Raw binary bits without any coding. Typically binary 1 maps to high and binary 0 to low |
| NRU(I) | Non-return-to-zero inverted | Either NRZ(M) or NRZ(S) |
| NRZ(M) | Non-return-to-zero mark | 0 maps to constant, 1 maps to toggle |
| NRZ(I) | Non-return-to-zero space | 0 maps to toggle, 1 maps to constant |
| NRZ(C) | Non-return-to-zero change | ? |
Advantages
NRZI is used because is easier to detect a transition at high speeds than measure exact voltage.
Example
You can see how the NRZI signal is translated to binary. A change in the signal results in a 1, no change results in a 0:
Figure 1: From wikipedia.org, licensed by CC BY-SA 3.0
