It will help us to update our knowledge about the communication sector and communication generation signal sector that will help us encourage about the topic and upgrade themselves
2. In wireless telephony, a cell is the
geographical area covered by a
cellular telephone transmitter.
Radio frequencies occupy the
range from a 3 kHz to 300 GHz.
3. A cellular network or mobile network is a
communication network where the last link is
wireless. The network is distributed over land
areas called cells, each served by at least one
fixed-location transceiver, known as a cell site
or base station.
4. Why hexagonal cell shape is perfect over square or triangular cell shapes in
cellular architecture?
Ans. The geographic area or cellular service area is divided into small hexagonal
region called cells. It is the basic unit of a cellular system. These cells collectively
provide coverage over larger geographical areas.
Hexagonal cell shape is perfect over square or triangular cell shapes in cellular
architecture because
1. It cover an entire area without overlapping i.e. they can cover the entire
geographical region without any gaps.
2. the hexagonal cell shape has a larger area than the square and the triangle,
thus less cells will be used to cover a certain geographical region.
3. . A hexagonal cell shape closely approximates the circular radiation
pattern(used by today's Omni-directional antennas)
of the base station (i.e. transmitter). circular cell shapes are
not used because of the gaps they leave in between them
if implemented.
5.
6. The different types of cells are given different names according to their
size and function:
Macro cells: Macro cells are large cells that are usually used for remote
or sparsely populated areas. These may be 10 km or possibly more in
diameter.
Micro cells: Micro cells are those that are normally found in densely
populated areas which may have a diameter of around 1 km.
Pico cells: Picocells are generally used for covering very small areas
such as particular areas of buildings, or possibly tunnels where coverage
from a larger cell in the cellular system is not possible. Obviously for the
small cells, the power levels used by the base stations are much lower and
the antennas are not position to cover wide areas. In this way the coverage
is minimised and the interference to adjacent cells is reduced.
7. Selective cells: Sometimes cells termed selective cells may be used where full 360
degree coverage is not required. They may be used to fill in a hole in the coverage
in the cellular system, or to address a problem such as the entrance to a tunnel etc.
Umbrella cells: Another type of cells known as an umbrella cell is sometimes
used in instances such as those where a heavily used road crosses an area where
there are microcells. Under normal circumstances this would result in a large
number of handovers as people driving along the road would quickly cross the
microcells. An umbrella cell would take in the coverage of the microcells (but use
different channels to those allocated to the microcells). However it would enable
those people moving along the road to be handled by the umbrella cell and
experience fewer handovers than if they had to pass from one microcell to the next.
16. DIFFERENCE/ ADVANTAGES OF 2G FROM 1G
1. Three times increase in spectrum efficiency in 3x increase
in overall system capacity.
2. 2G provide limited Internet browsing and SMS services
17. 3G WIRELESS NETWORK
1. Multi megabit Internet access.
2. Unparalleled network capacity.
3. Ubiquitous ‘always on’ access.
4. Ability to receive live music.
5. To conduct interactive web sessions.
6. Simultaneous voice and data access with multiple
parties at the same time using a single mobile
handset, whether driving walking or standing still.
18.
19. LIMITATIONS OF 3G
1.High I/p fee for the 3G services.
2.Greater differences in the licensing term.
3. Current high debt of many telecommunication companies making
it more of a challenge to build the necessary infrastructure of
3G.
4.Member state support to the financially troubled operators.
5. Health aspects of the effects of em waves.
6. Expense of 3G phones.
7. Lack of 2G mobile user buy in for 3G wireless service.
8. Lack of coverage become it is still new service.
9. High prices of 3G mobile services in some countries including
Internet access.
20.
21. CHARACTERISTICS OF 4G
1. Fully IP based integrated system.
2. Data rate :100Mbit/s & 1Gbit/s.
3. End to end QoS.
4. High security.
5. Speeds: 100Mbit/s & 1Gbit/s
6. It combines technologies such as WiFi & WiMax
7. A spectrally efficient system.
8. High network capacity.
22. 4G CHARACTERISTICS
9. Offering any kind of services.
10. Smooth handoff across heterogeneous network.
11. Seamless connectivity & global roaming across
multiple across.
12. High quality of service.
13. Interoperability with the existing wireless
broadband.
14. An all IP, packet switched network.
23. APPLICATIONS OF 4G
1.Wireless broad band access
2. Multimedia messaging service
3.Video chat
4.Mobile TV
5.High definition TV content
6. DV 13
7.High quality service.
24.
25.
26.
27.
28. CHARACTERISTICS OF 5G
5G will provide some extraordinary features and
advantages.
1). 5G has better coverage area and high data rate at the edge of
the cell.
2). It has low battery consumption.
3). Availability of multiple data transfer path.
4). Around 1 Gbps data rate is easily possible.
5). Security is more.
6). Energy efficiency and spectral efficiency are good.
Due to the above advantages, 5th generation wireless system is
very much essential.
29. APPLICATIONS OF 5G TECHNOLOGY
1. One can be able to perceive his/her sugar level with his/her mobile.
2. One can be able to charge his/her mobile with his/her own heartbeat.
3. One can be able to view his/her residence in his/her mobile when someone enters.
4. The mobile will ring according to our mood.
5. One can be able to pay all bills in a single payment with his/her mobile.
6. One can get the live share value.
7. One can be able to navigate the train for which he/she might be waiting.
8. One can be able to vote from his/her mobile
9. One can be able to sense tsunami/earthquake before it occurs.
10. Our mobile can share our work load.
11. One can get an alert in his/her mobile when someone opens his/ her intelligent car.
12. One can be ale to lock his/her car or bike with his/her mobile when he/she forgets to
do so.
13. We can be able to expand our coverage using our mobile phone.
14. Our mobile can perform radio resource management.
30.
31. GSM FREQUENCY BAND
GSM operates at four main frequency bands :
i.900 MHz : Used by most GSM networks.
ii.1800 MHz : In UK
iii. 1900 MHz : AS PCS concept in USA.
iv.800 MHZ : Enhancing now.
32. KEY TERMS
An MS can have one of the following states :
1.Idle: MS is ON but a call is not in progress.
Registration, Roaming, International Roaming,
Location Updating, Paging.
2.Active : MS is ON and A call is in progress.
Handover
3.Detached : MS is OFF.