Tag Archives: WCDMA / 3G

What is 3G? or WCDMA?

3G is new upgraded cdma technology, in simple word its Wide band Code Devision Multiple Access Technology (WCDMA). This is first technology in which video call possible means voice and

How Wireless Narrowband Local-Loop Systems in Wimax ?

Naturally, the first application for which a wireless alternative was developed and deployed was voice telephony. These systems, called wireless local-loop (WLL), were quite successful in developing countries such as

What is the 3GPP?

The 3rd Generation Partnership Project (3GPP) is a collaboration between groups of telecommunication associations, to make a globally applicable third generation 3G mobile phone system specification within the scope of

Main Characterictics of WCDMA

Support two basic modes: FDD and TDD modes High chip rate (3.84 Mcps) and data rates (up to 2 Mbps) Employs coherent detection on uplink and downlink based on the

Process Gain in WCDMA

How Process Gain works in 3G? Process Gain = 10 Log (Chip rate/Bit Rate) Process gain differs for each service. If the service bit rate is greater, the process gain

WCDMA Network Architecture

WCDMA including the RAN (Radio Access Network) and the CN (Core Network). The RAN is used to process all the radio-related functions, while the CN is used to process all

Signal Fading

Slow fading: In case shadow effect is caused by obstacles, and the receiving signal strength decreases but the field strength mid-value changes slowly with the change of the topography, the

WCDMA Source Coding

AMR (Adaptive Multi-Rate) Speech A integrated speech codec with 8 source rates The AMR bit rates can be controlled by the RAN depending on the system load and quality of

WCDMA Block Coding – CRC

Block coding is used to detect if there are any uncorrected errors left after error correction. The cyclic redundancy check (CRC) is a common method of block coding. Adding the

Correlation in WCDMA

How Correlation works in WCDMA ? Correlation measures similarity between any two arbitrary signals. Identical and Orthogonal signals: Correlation is used to measure similarity of any two arbitrary signals. It

WCDMA Interleaving

How WCDMA Interleaving ? Effect Interleaving is used to reduce the probability of consecutive bits error Longer interleaving periods have better data protection with more delay Channel coding works well

WCDMA Channel Coding

Effect Enhance the correlation among symbols so as to recover the signal when interference occurs Provides better error correction at receiver, but brings increment of the delay Channel Types No