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

Telecom Interview Questions & Answers "IMPORTANT"

Telecom Interview Questions & Answers

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.

Antenna Principals For Mobile in Telecommunication

Antenna Systems and Its Principals

In the last few years a large technological jump has taken place in the field of mobile communications due to the introduction of new mobile communication networks (GSM/PCN). The number of subscribers worldwide has risen to over 150 Million. Figure. shows an overview of the mobile communications services and the relevant frequency ranges within Germany alone.

Quick Overview " Microwave "

Quick Overview " Microwave "

TRANSMISSION SYSTEMS

Introduction To Transmission Systems
•        Transmission systems form the backbone of any networks.
•        Normally transmission systems include SDH, PDH, ATM, Microwaves, leased lines.
•        In GSM normally the core network is located in the same premises and are mostly interconnected by fixed wireline. In huge network consisting of many MSC located at different places the interconnection may be through any of the transmission systems mentioned above.
•        The Access network consists of BSC’s with many BTS’s connected to them in various transmission topologies. Normal practice is to connect various BSC’c to the MSC via fiber and different BTS’s connected to BSC via microwave in Daisy chain, star or any other topology. However there can be many different ways of implementation.

E1

Fading, Diversity & Interference in Telecommunication.

Fading, Diversity & Interference

RF ( Radio Frequency ) Optimization & Planning "Q n A"

What is Mobile Station Roaming Number (MSRN)?

The MSRN is used to identify a subscriber when routing the call from the GMSC to the visited MSC for mobile terminating calls.. It is allocated by the MSC/VLR currently serving the subscriber on a call basis (temporary assignment) 

2G Channels In Telecom.

MULTIPLE TECHNIQUES
In order for several links to be in progress simultaneously in the same geographical area without mutual interference , multiple access techniques are deploy
The commonly used multiple access techniques
–       Frequency Division Multiple Access  (FDMA )
–       Time Division Multiple Access (TDMA )
--Code Division Multiple Access (CDMA )

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