Question

Why is PCM called a Modulation Technique?

Answer 1

Hint: Modulation is of various types based on the moderation of various factors such as frequency, amplitude, etc. on every modulated signal. They are Amplitude Modulation, Frequency Modulation, Phase Modulation, Pulse Code Modulation (PCM), Polarisation Modulation, and Quadrature Amplitude Modulation (QAM). Hence elaborate on the Pulse Code Modulation.

Complete Step By Step Answer:
Digital Modulation is of the following types:
-Pulse Amplitude Modulation (PAM)
-Pulse Width Modulation (PWM)
-Pulse Code Modulation (PCM)
In a PCM path, the amplitude of the analog signal is tested regularly at uniform intervals, and each sample is quantized to the nearest value within a range of digital steps. The low pass filter helps in preventing altering of the message signal. When a digital signal goes through Pulse Code Modulation, it converts the information from an analog form into a binary from one and zero. From the demodulation process, we can achieve the original analog signal form. Pulse Code Modulation techniques are used to make a series of numbers or digits in binary form. Hence this process is called digital modulation. The amplitude at that instant time of the signal sample is indicated by the binary codes. It is the process of converting an analog signal into a digital signal using 3 basic functions such as
-Sampling
-Quantization
-Coding
Hence Modulation could be a method of converting the data from the first analog form into a binary form. From the demodulation process, we will achieve the first analog signal form.

Note:
Pulse Code Modulation techniques are used to produce a series of numbers or digits in binary form. Hence this kind of process is called digital modulation. The amplitude at that instant time of the signal sample is shown by the binary codes.