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Reverse Link Traffic Channel Physical Layer in CDMA

The CDMA reverse link uses a different coding scheme to transmit data. Unlike the forward link, the reverse link cannot support a pilot channel for synchronous demodulation (since each mobile station would need its own pilot channel). The lack of a pilot channel is partially responsible for the reverse link’s lower capacity than the forward … Read more

How Forward Link Channel Format in CDMA

The Base Station transmitter signal is, however, the composite of many channels (with a minimum of four). The Pilot channel is unmodulated (Walsh code 0); it consists of only the final spreading sequence (short sequences). The Pilot channel is used by all mobiles linked to a cell as a coherent phase reference and also provides … Read more

What type of modulation is BPSK?

Binary Phase Shift Keying (BPSK) is a digital modulation scheme that falls under the broader category of phase shift keying (PSK). It is a fundamental modulation technique used in digital communication systems to transmit binary data. Let’s delve into the details of the type of modulation that BPSK employs: 1. Basic Principles of BPSK: Phase … Read more

Why OQPSK is preferred over QPSK?

Offset Quadrature Phase Shift Keying (OQPSK) is a modified version of Quadrature Phase Shift Keying (QPSK) that addresses certain issues associated with traditional QPSK modulation. OQPSK introduces an offset in the timing of the transmitted signal to improve spectral efficiency and minimize the occurrence of transitions at symbol boundaries. Let’s explore in detail why OQPSK … Read more

Why QAM is preferred over QPSK?

Quadrature Amplitude Modulation (QAM) and Quadrature Phase Shift Keying (QPSK) are both digital modulation schemes, but they differ in how they encode data onto the carrier signal. QAM is often preferred over QPSK in certain scenarios due to its higher data-carrying capacity and spectral efficiency. Let’s explore in detail why QAM is preferred over QPSK: … Read more

What is the speed of CDMA 1x?

The speed of CDMA 1x, often referred to as CDMA2000 1x or simply 1x, represents the data transfer rate in Code Division Multiple Access (CDMA) networks. CDMA 1x is a 2G and 3G wireless communication standard that provides voice and data services. Let’s explore the speed of CDMA 1x in detail: 1. Basic Introduction to … Read more

What is the structure of CDMA network?

The structure of a Code Division Multiple Access (CDMA) network is complex, involving various components and layers to facilitate the transmission of voice and data signals in a wireless communication system. CDMA is a multiple access technique that allows multiple users to share the same frequency band simultaneously, using unique codes to distinguish between signals. … Read more

What is the technical specification of TD-SCDMA?

Time Division-Synchronous Code Division Multiple Access (TD-SCDMA) is a unique 3G mobile communication standard developed in China. It combines time division duplex (TDD) and code division multiple access (CDMA) technologies. Here are the technical specifications of TD-SCDMA: 1. Frequency Band and Spectrum: TDD Spectrum: TD-SCDMA operates in the TDD spectrum, meaning that it uses the … Read more

What is the technology of CDMA 1x?

Code Division Multiple Access 1x (CDMA 1x) is a digital wireless technology that falls under the CDMA2000 family of standards. It represents an evolution of the original CDMA technology, providing enhancements for both voice and data communication. Here is a detailed explanation of the technology of CDMA 1x: 1. Basic Principles of CDMA: Spread Spectrum … Read more

What is the use of QPSK?

Quadrature Phase Shift Keying (QPSK) is a digital modulation scheme widely used in communication systems to encode and transmit data. QPSK offers advantages in terms of spectral efficiency and robustness against channel impairments. Let’s delve into the detailed use and applications of QPSK: 1. Basic Principles of QPSK: Phase Modulation: QPSK is a type of … Read more