GSM Technology

Rx_Level_Full is measured when DTX is off & Sub is when DTX

is on.

RX Lev Full: Its is nothing but the Mobile transmit the

measurment report(SACCH multiframe) for every 480ms. this

multiframe containes 104 TDMA frames, in 104 TDMA frames 4

TDMA frames for Decode the BSIC and remaining 100 TDMA

frames for Average measurment of serving cell and

neighbouring cell.This average measurment of 100 TDMA frames

are RX Lev Full

RX Lev Sub: DTX is a discontinouse trasmission, When the

mobile conversation 40% of the time either Trasmitter or

Receive is idle. When DTX is ON, DTX will switch off the

Trasmitter or Receiver when they is no speech Pulses. only

few TDMA frames will trasmit, the average of this TDMA

frames is called RX Lev Sub, give you proper measurment of

RX level

Long Term Evolution (LTE) is the next step from 3G/WCDMA &

HSPA for many already on the GSM technology curve but also

for others too, such as CDMA operators. This new radio

access technology will be optimized to deliver very fast

data speeds of up to 100Mb/s downlink and 50Mb/s uplink

(peak rates).

Designed to be backwards-compatible with GSM and HSPA, LTE

incorporates Multiple In Multiple Out (MIMO) in combination

with Orthogonal Frequency Division Multiple Access (OFDMA)

in the downlink and Single Carrier FDMA in the uplink to

provide high levels of spectral efficiency and end user data

rates exceeding 100 Mbps, coupled with major improvements in

capacity and reductions in latency. LTE will support channel

bandwidths from 1.25 MHz to 20 MHz and both FDD and TDD

operation.

Although both LTE and WiMAX use the OFDMA air interface, LTE

has the advantage of being backwards compatible with

existing GSM and HSPA networks, enabling mobile operators

deploying LTE to continue to provide a seamless service

across LTE and existing deployed networks.

Several major mobile operators, including some running CDMA

networks today, have indicated they will adopt LTE in the

next few years. Japanese mobile operator NTT DOCOMO has said

that it is aiming to launch a commercial LTE network by the

end of 2009, while in the U.S., the largest CDMA operator,

Verizon Wireless, is currently trialing LTE with a view to

launching a commercial LTE service in 2010.

LTE- Advanced

LTE-Advanced extends the technological principles behind LTE

into a further step change in data rates. Incorporating

higher order MIMO (4x4 and beyond) and allowing multiple

carriers to be bonded together into a single stream, target

peak data rates of 1Gbps have been set.

LTE-Advanced also intends to use a number of further

innovations including the ability to use non-contiguous

frequency ranges, with the intent that this will alleviate

frequency range issues in an increasingly crowded spectrum,

self back-hauling base station and full incorporation of

Femto cells using Self-Organising Network techniques.

LTE-Advanced will be 3GPP’s technology as a candidate for

the ITU-R IMT-Advanced process, which is intended to

identify ‘4G’ technologies.

The main difference between GSM and CDMA is: In GSM, the

entire frequency band is not available to the end-user,

while in CDMA the entire frequency band is available to the

end-user. So, the Frequency Re-use factor is 1 in CDMA.

GSM Works as follows:

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The entire frequency band is divided into chunks and

each such chunk is divided into timeslots and each such

portion is made available to a user.

CDMA Works as follows:

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The entire frequency band is available to the user. So,

in order to differentiate, the transmission from each user

is "spread" or coded using an unique code given to

individual user. At the receiving end, the spread

information is decoded.

★ Short form of Global System for Mobile Communications, is a wireless network system

★ A standard for digital cellular mobile communications

★ International roaming arrangements are enabled among mobile network operators, by providing the subscribers to use their personal mobile phones anywhere in the world.

★ GSM is considered as second generation mobile, as signaling and speech channels are digital

★ The carriers can be replaced without replacing mobile phones.

★ The ubiquity of GSM implementations is also enabling the switching between network operators, who can choose equipment from many GSM equipment vendors.

★ GSM pioneered low cost SMS implementation

★ The GSM standard includes a worldwide emergency telephone number feature.

★ The services offered by GSM are ISDN compatible

★ GSM allows synchronous data and asynchronous data to be transported as bearer service, one of the telecommunication services offered by GSM, and forms ISDN terminal

★ The data could be either transparent service or nontransparent service

★ Telephony is one of the services offered by GSM, which an emergency and the service provider is notified by dialing 3 digits

★ By using appropriate fax adapter, G3 fax service is supported

★ One of the features of GSM is Short Messaging Service

★ Certain services, namely supplementary services are provided on top of teleservices or bearer services by GSM, such as, caller identification, call forwarding, multiparty conversations, barring outgoing calls and call waiting.