Pulse Code Modulation Overview

A method of modulating a signal by varying the width of a constant-amplitude pulse, where wider pulses represent higher signal amplitudes.

A method of modulating a signal by varying the position of a constant-width pulse within a fixed time slot, where a pulse further to the right indicates a higher signal amplitude.

A method of modulating a signal by varying the amplitude of a constant-width, constant-position pulse, where the amplitude of the pulse directly reflects the sampled signal amplitude.

A method of converting an analog signal to a digital format for transmission by sampling the signal and representing each sample as a binary code, where each code has a fixed length and represents a specific amplitude value.

In PWM, the maximum analog signal amplitude corresponds to the widest pulse, while the minimum analog signal amplitude corresponds to the narrowest pulse.

In PPM, the position of the pulse within the allotted time slot is determined by the signal amplitude. A higher amplitude signal will push the pulse further to the right.

PAM's strength lies in its ability to closely resemble the original analog signal, making it easier to decode and interpret.

PCM relies on fixed-length binary codes to represent the sampled signal amplitudes, ensuring consistent and efficient transmission of information.

A type of sampling where the sampled values are held constant at the exact sampling instant, creating a series of rectangular pulses.

A type of sampling where the sampled values are allowed to change continuously between sampling instants.

A circuit that periodically samples an analog input signal and converts those samples into a multilevel PAM signal.

A device that converts an analog signal into a digital signal, typically using binary code.

A device that converts a digital signal back into an analog signal.

An integrated circuit that performs both encoding and decoding functions for PCM signals.

The error introduced by the amplitude of the sampled signal changing during the sample pulse time, preventing perfect reproduction in the PCM receiver.

The time it takes for the FET analog switch to turn on and deposit the analog sample voltage onto the capacitor (C1).

The capacitor in the sample-and-hold circuit that acts as the hold circuit.

A filter used to correct distortions in the sampled signal's frequency spectrum, often used in PCM systems.

A network that spans a city or a large geographical area, connecting different networks within that region. It is often used to connect smaller networks, such as Local Area Networks (LANs), to each other, enabling communication between different organizations or institutions within the same metropolitan area.

A network topology where devices are connected to a central hub, forming a star-like structure. All communication passes through the hub, making it a central point of failure. However, it simplifies network management and troubleshooting.

A network topology where devices are connected in a circular fashion, with each device connected to two others. Data travels in both directions around the ring, and if one connection breaks, communication can still flow through the remaining connections. It provides redundancy and fault tolerance.

A network that covers a small geographical area, typically within a building or a group of buildings. It is commonly used for connecting devices within a company, school, or home. Its primary goal is to facilitate communication and resource sharing among devices in close proximity.

A network topology where devices are connected in a decentralized manner, forming a mesh-like structure. Any device can communicate directly with any other device, creating a highly reliable and redundant network. However, it can be complex to set up and manage.

A network topology where devices are connected by a single communication line, with data traveling in a linear fashion from one device to another. It is simple and cost-effective, but it is prone to single points of failure. If one connection breaks, the entire network is disrupted.

A device that connects multiple networks, filtering and forwarding packets based on their destination addresses. It improves network efficiency by reducing traffic congestion and enhancing security by controlling access between networks.

A group of connected devices that share resources and communicate with each other. It can be classified based on geographic scope, such as LAN, MAN, or WAN.

Pulse Code Modulation (PCM) is a technique used to convert an analog signal, like sound or video, into a digital format. It involves sampling the signal at regular intervals and assigning a binary code to each sample. This code represents the amplitude of the signal at that moment, allowing the signal to be digitally transmitted or stored.

PCM makes digital communication reliable by transforming analog signals into a standardized digital form. This helps ensure that data is transmitted accurately and without loss of quality. It's also essential for digital storage of analog signals because it allows for their accurate reproduction.

In PCM, the sampling rate determines how often the analog signal is sampled. A higher sampling rate means more samples are taken per second, resulting in a more accurate representation of the original signal. It's like capturing more snapshots to create a clearer picture of the signal's changes.

A quantizer in PCM assigns a specific digital value to each sampled amplitude. The number of bits used for this quantization determines the accuracy of the digital representation. More bits mean finer detail, but also require more storage space.

PCM is widely used in various applications, including voice communications, telecommunications, digital audio and video recordings, and medical imaging.

PCM is a powerful technique that offers a balance between accuracy and efficiency. It enables transmission and storage of analog signals in a digitally stable, efficient format. As technology advances, PCM continues to evolve, incorporating more efficient coding methods and higher fidelity.

While PCM is effective in transmitting analog signals digitally, there are other modulation techniques like pulse width modulation (PWM) and pulse position modulation (PPM). Each has its own strengths and weaknesses based on the application's needs and constraints.

PCM offers a digital solution for conveying analog information, playing a crucial role in modern communication and data processing technologies.

A network that connects devices within a small physical area like a home or office.

A network that connects devices over a wide geographical area.

A type of network cable that uses two insulated wires twisted together to reduce interference.

A type of Ethernet connector with eight pins, commonly used for network cables.

A network device that forwards data packets between networks.