Pulsed code modulation and Demodulation-Pulse Modulation and Demodulation-Communication Engineering

TL;DR

Pulse Code Modulation (PCM) is a digital signal processing technique that involves encoding and decoding analog signals for transmission and retrieval, using processes such as sampling, quantization, and digital-to-analog conversion.

Transcript

hello friends now we will see the pulse code modulation first we will see the encoder of this now in the encoder the continuous modulating signal is applied to a low pass filter unwanted higher frequency component of the modulating signal is being removed at a low pass filter then it coupled to the sample and hold here sample and hold circuit is no... Read More

Key Insights

• 📡 Pulse Code Modulation (PCM) is a digital encoding technique used for transmission and storage of analog signals.
• 😘 The PCM encoding process involves stages such as low pass filtering, sampling, quantization, and analog-to-digital conversion.
• 💗 The PCM decoding process reverses the encoding stages, involving inverse quantization, parallel to serial conversion, pulse generation, digital-to-analog conversion, and filtering.
• 👻 PCM allows for efficient digital storage and transmission of analog signals.
• 🥹 Sampling and holding in PCM helps to accurately capture the amplitude of the modulating signal.
• 🎚️ Quantization in PCM involves approximating the continuous analog signal into discrete levels.
• 💁 Digital-to-analog conversion in PCM is used to convert the digital signal back into its original analog form.

Questions & Answers

Q: What is Pulse Code Modulation (PCM)?

Pulse Code Modulation is a digital signal processing technique used to convert analog signals into binary code for transmission and storage, and then decode them back to analog form.

Q: What are the main steps involved in the PCM encoding process?

The PCM encoding process includes low pass filtering to remove unwanted higher frequency components, sampling and holding to capture samples of the signal, quantization to approximate the signal, and analog-to-digital conversion to convert the signal into digital form.

Q: How does the PCM decoder work?

The PCM decoder reverses the encoding process by using processes such as inverse quantization to retrieve the original signal, parallel to serial conversion to convert the signal into a serial form, pulse generation for synchronization, digital-to-analog conversion, and filtering to obtain the original analog signal.

Q: What is the role of the pulse reference generator in PCM encoding?

The pulse reference generator generates reference pulses that synchronize the sampling time of the sample and hold circuit, ensuring accurate sampling and quantization of the modulating signal.

Summary & Key Takeaways

• Pulse Code Modulation involves the process of encoding an analog signal into a digital form for transmission, and decoding it back to analog form for retrieval.

• The PCM encoder involves steps such as low pass filtering, sampling and holding, quantization, and analog-to-digital conversion.

• The PCM decoder reverses the steps of the encoding process, involving inverse quantization, parallel to serial conversion, pulse generation, digital-to-analog conversion, and filtering.