CDMA

Quadrature Phase Shift Keying (QPSK) is a digital modulation scheme that transmits data by varying the phase of the carrier signal. There are two main types of QPSK: Offset QPSK (OQPSK) and π/4-QPSK. Let’s explore the details of each: 1. Offset QPSK (OQPSK): OQPSK is a modified version of QPSK that addresses certain issues related … Read more

Code Division Multiple Access (CDMA) is a digital cellular technology that allows multiple users to share the same frequency band simultaneously. It operates based on the principle of spread spectrum communication, where each user is assigned a unique code to differentiate their signals. Here is an in-depth explanation of how a CDMA network works: Spread … Read more

Quadrature Phase Shift Keying (QPSK) and 16-Quadrature Amplitude Modulation (16QAM) are both digital modulation schemes used in communication systems to transmit data over radio frequency channels. While they share similarities, there are distinct differences in terms of modulation complexity and data transmission efficiency. Here’s a detailed explanation of how 16QAM differs from QPSK: 1. Basic … Read more

Quadrature Phase Shift Keying (QPSK) is a digital modulation scheme used in communication systems to transmit data over radio frequency channels. Generating a QPSK signal involves modulating digital data onto a carrier wave by manipulating its phase. Here’s a detailed explanation of how to generate a QPSK signal: 1. Digital Data Input: QPSK operates by … Read more

Phase Shift Keying (PSK) is a digital modulation technique used in various communication systems to transmit data by varying the phase of a carrier signal. PSK finds applications in a wide range of systems due to its simplicity, efficiency, and ability to adapt to different communication requirements. Here’s a detailed explanation of the systems where … Read more

4-PSK (4-Phase Shift Keying) and QPSK (Quadrature Phase Shift Keying) are both digital modulation techniques that involve varying the phase of a carrier signal to transmit digital data. While they share some similarities, they are not exactly the same. Let’s delve into the details of both modulation schemes and explore their similarities and differences. 1. … Read more

TD-SCDMA, or Time Division-Synchronous Code Division Multiple Access, is a mobile communication standard developed in China. It was designed as an alternative to existing 3G technologies like WCDMA and CDMA2000. TD-SCDMA employs a combination of time division and code division multiplexing techniques to facilitate communication in a wireless network. Time Division Multiplexing (TDM): TD-SCDMA utilizes … Read more

CDMA (Code Division Multiple Access) is a digital cellular technology that enables multiple users to share the same frequency band simultaneously. While CDMA was once a prevalent technology, its usage has significantly declined in recent years. The main reason for this decline is the widespread adoption of GSM (Global System for Mobile Communications) and its … Read more

What are the features of IS-95? What are the features of IS-95? IS-95, short for Interim Standard-95, is a second-generation (2G) digital cellular technology that played a significant role in the evolution of mobile communication. Also known as CDMAOne, IS-95 was developed by Qualcomm and introduced as a digital replacement for the analog cellular systems … Read more

What are the disadvantages of multiple access techniques? Multiple Access Techniques are methods used in telecommunications to allow multiple users or devices to share a common communication medium, such as a radio channel or a network. While these techniques are essential for efficient utilization of resources, they also come with disadvantages. In this detailed explanation, … Read more