Orthogonal Code Usage – Coding & Decoding in WCDMA
How Orthogonal Code works in WCDMA? 1.Coding By spreading, each symbol is multiplied with all the chips in the orthogonal sequence assigned to the user. The resulting sequence is processed…
Here You Get how 3G work, Go inside WCDMA Technology and wcdma rf optimization.
How Orthogonal Code works in WCDMA? 1.Coding By spreading, each symbol is multiplied with all the chips in the orthogonal sequence assigned to the user. The resulting sequence is processed…
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…
A transmitted signal changes as it travels to the receiver. The effect of these changes is commonly referred to as fading. The fading results from the superimposition of transmitted signals,…
In 1998, the Institute of Electrical and Electronics Engineers (IEEE) formed a group called 802.16 to develop a standard for what was called a wireless metropolitan area network, or wireless…
Spreading consists of 2 steps: Channelization operation, which transforms data symbols into chips Scrambling operation is applied to the spreading signal Spreading means increasing the bandwidth of the signal beyond…
How Spreading & Dispreading in WCDMA-3G ? Traditional radio communication systems transmit data using the minimum bandwidth required to carry it as a narrowband signal. CDMA system mix their input…
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…
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…
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…
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…
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…
Source coding can increase the transmitting efficiency. Channel coding can make the transmission more reliable. Spreading can increase the capability of overcoming interference. Through the modulation, the signals will transfer…