Data or information can be stored in both analog and digital formats. In order for a computer to use data, it must be in discrete digital form. Like data, signals can be both analog and digital. In order for data to be transmitted digitally, it must first be converted to digital format.
Digital-to-Digital Conversion
It can be done in two ways, line Coding and block encoding.
Line coding
Linear code is the code that is used to transmit a digital signal through a transmission line. This encoding process is chosen to avoid interference and signal distortions, such as between codes.
Unipolar encoding, is a line code. Positive voltage represents binary 1 and zero voltage represents binary zero. It is the simplest linear code that encodes the bit stream directly and is similar to the choppy coding in modulation.
Bipolar encoding, also known as bipolar transmission, is the main musical method of transmitting binary data over a wire or cable. There are two lower and upper logical conditions, represented by the digits 0 and 1, respectively, and the bandwidth is inversely proportional to each data bit time.
Polar Encoding, scheme uses multiple voltage levels to represent binary values. There are four types of polar notation: polar zero non-polarity (polar NRS) and two different levels of effort used to represent binary values. Normally a positive voltage represents 1 and a negative value 0.
NRZ-L and NRZ-I — These are the same ones mentioned in the capacitance (voltage). Voltage level is specified for NRZ-L (NRZ-level), binary 1 is the medium high logical level, binary 0 is the logical level of the card, NRZ-I is the parameter (NRZ-invert), the signal is transmitted and the signal we follow from the signal. Evolution is logical 0.
Manchester -Manchester encoding is a method of data modification that can be used in many situations, but is particularly useful for transmitting binary data based on analog signals, high-speed radio signals, optical or digital high-speed or long-range ranges.
Analog-to-Digital Conversion
The most common method of changing the analog signal to digital data is called pulse code modulation (PCM). The PCM encoder includes the following three operations.
- Sampling
- Quantization
- Encoding
