Wcdma Channels ( Detailed ) CHAPTER ONE/THREE

WCDMA Channels

Logical Channels are not actually channels but rather they can be defined as different tasks performed by the network and the UE at different times.They describe the type of information to be transferred.
Logical channels are categorized into control channels and traffic channels.Control channels carry the control plane information.Traffic Channels carry the user plane information.
Transport channels describes how the logical channels will be transferred, or it can be defined as how and with what characteristics data is transferred over the interface.
It comes into two groups:
·       Dedicated Channels
·       Common Channels
Radio Frame Structure

Frequency Hopping & RF-Optimization Planning in Telecommunication.

Frequency Hopping

                                                         

           

FREQUENCY HOPPING

Telecom Interview Question & Answer.

(A)What is ciphering
Ciphering modifies the contents of the eight interleaved blocks through the use of encryption techniques to the particular mobile station and base transceiver station.
Two types of ciphering algorithms, called A3 and A5, are used in GSM to prevent unauthorized network access and privacy for the radio transmission respectively.
How many carrier frequencies are there in GSM-900 and DCS-1800? How much is the separation between the carrier frequencies?
124 carriers.
There are 8 channels in each carrier.
Channel separation is 200 KHz.
What is the Downlink and uplink spectrum is allocated to DCS-1800?
1800 MHz. Up link Frequency 1725-1780 MHZ.
Down link Frequency 1820-1870 MHz