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Wireless raodmap

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What is GPRS

General Packet Radio Service General -> not restricted to GSM use (DECT ?, 3rd generationsystems ?)

Packet Radio -> enables packet mode communication over air

Service, not System -> existing BSS (partially also NSS)

infrastructure is used

Main benefits Resources are reserved only when needed and charged

accordingly

Connection setup times are reduced

Enables new service opportunities

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GPRS characteristics

GPRS uses packet switched resource allocation resources allocated only when data is to be sent/received

Flexible channel allocation one to eight time slots

available resources shared by active users

up and down link channels reserved separately

GPRS and circuit switched GSM services can use same time

slots alternatively

Traffic characteristics suitable for GPRS Intermittent, bursty data transmissions

Frequent transmissions of small volumes of data

Infrequent transmission of larger volumes of data

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GPRS Applications

Standard data network protocol based

IP based applicationsWWW, FTP, Telnet, ...

Any conventional TCP/IP based applications

X.25 based applications

Packet Assembly/Disassembly (PAD) type approach

GPRS specific protocol based

Point-to-point applications

Toll road system, UIC train control system

Point-to-multipoint applications

Weather info, road traffic info, news, fleet management

SMS delivery (GPRS as a bearer for SMS)

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GPRS Architecture

BTS

BTSMS

BSC Gb

SGSN

Gf

GsGr

DEIR

MSC/VLR

HLR

Gc

Gn

GGSNGi

PDN

Gp GGSN

Other GPRS

PLMN

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Users' benefits of GPRS

GPRS Selling arguments: Higher capacity Internet access

Up to 171,2 kbps in theory, 40 kbps in practice Quicker access to Internet

No set up time, Iternet access all the time available

Lower cost

Flat rate or volume based billing Or no cost

via anonymous access (somebody else pays the bill)

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HIGH FREQUENCY

HF stands for HIGH FREQUENCY

These are the frequencies from 1.8* to 30 MHz

or the 160 meterto 10 meter bands. HF is also known as shortwave.

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HF Band AllocationMeter Band Frequency (MHz)

CW, RTTY, Data Voice

160 1.800 - 2.000

80 3.500 - 3.750 3.750 - 4.000

40 7.000 - 7.150 7.150 - 7.300

30 10.100 - 10.150

20 14.000 - 14.150 14.150 - 14.35017 18.068 - 18.110 18.110 - 18.168

15 21.000 - 21.200 21.200 - 21.450

12 24.890 - 24.930 24.930 - 24.990

10 28.000 - 28.300 28.300 - 29.70

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Who Uses HF? Because of the ability to communicate over

long distances, HF is used by many

government, military, and commercialagencies worldwide

Amateur Radio operators all over the worlduse HF for the same reasons.

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Radio waves change direction

when they enter the ionosphere

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Conclusion

GPRS provides efficient access to Packet DataNetworks with different qulity level through put.

Multislot operation in GPRS leads to efficient channelutilization.

GPRS is more effective for long data packettransmission than short ones.