The process of converting discrete-time continuous valued signal into discrete-time discrete valued (digital) signal is known as quantization.

Quantization:
- Quantization is a fundamental step in the process of converting analog signals to digital signals.
- It involves mapping the continuous range of input values to a finite set of discrete output values.
- The purpose of quantization is to reduce the infinite number of possible input values to a finite number of levels that can be represented digitally.

Steps in Quantization:
1. Sampling:
- Before quantization, the continuous-time analog signal is first sampled to obtain a discrete-time signal.
- Sampling involves taking periodic samples of the continuous signal at a fixed interval of time.
- The resulting discrete-time signal represents the original signal at specific time instants.

2. Quantization Levels:
- The next step is to determine the number of quantization levels required for representing the discrete-time signal.
- The number of levels is determined by the bit depth or the number of bits used to represent each sample of the signal.
- The more levels or bits used, the higher the fidelity and accuracy of the digital representation.

3. Quantization Error:
- The quantization process introduces an error known as quantization error.
- This error is the difference between the actual value of the input signal and the quantized value.
- The quantization error can introduce noise and distortion to the digital signal.

4. Quantization Process:
- In the quantization process, each sample of the discrete-time signal is rounded or truncated to the nearest quantization level.
- The quantization levels are evenly spaced in the range of the input signal, with each level represented by a unique binary code.
- The quantized samples are then represented digitally using binary codes.

Conclusion:
- Quantization is an essential step in the conversion of analog signals to digital signals.
- It involves mapping the continuous range of input values to a finite set of discrete output values.
- The quantization process introduces quantization error, which can affect the fidelity and accuracy of the digital signal.