NRZ
It has two variants: NRZ and NRZI
1. NO RETURN TO ZERO (NRZ, NORETURN TO ZERO)
This scheme uses a different voltage level for each of the binary digits.
The codes that follow this strategy share the property that the voltage level remains constant for the duration of the bit. The 'binary 1' is represented by a negative voltage, and the 'binary 0' is represented by a positive tension.
2. NRZI (NORETURN TO ZERO, INVERT ON ONES)
The encoding in this scheme is as follows:
- If the binary value is '0' it is encoded with the same signal as the previous bit.
- If the binary value is '1' it is encoded with a different signal than the one used for the preceding bit.
ADVANTAGES
- Synchronization.
- It has no DC components.
- Error detection.
DISADVANTAGES
- Presence of a DC component.
- Lack of synchronization capacity.
