Review of Cellular and Wireless Communications.

Running head: REVIEW OF CELLULAR AND WIRELESS COMMUNICATIONS
Review of Cellular and Wireless Communications
Name of the Student
Name of the University
Author Note

REVIEW OF CELLULAR AND WIRELESS COMMUNICATIONS1
1. Ways to increase Cellular System Capacity
The five key ways by which the capacity of cellular network systems can be
improved are as follows:
1. Addition of Cell Sites
2. Addition of Sectors
3. Addition of Carriers
4. Improving Air Interface Capability
5. Use of Smart Antennas
Cell Sites: Addition of cell sites are expensive yet very effective an approach to
increasing capacity (Andryeyev and Mitschele-Thiel, 2017). Usually the process of
adding newer real estate consumes lot of time and complications.
Cell Sectors: Addition of sectors like change from three sectors to six sectors is an
effective way in approximating new cell introductions. This not necessarily doubles
the capacity since the petals of six sector coverage does not interleave so well as
three sector coverage.
Cell Carriers: Addition of carriers that is bandwidth increases capacity directly
(Bayhan, Zheng, Chen, Di Francesco, Kangasharju & Chiang, 2017). The Long Term
Evaluation or LTE standard excels in using increased bandwidth without increasing
overheads of control channels.
Air Interface Capability: Improving the capability of air interface includes evolution
from Universal Mobile Telecommunications or UMTS towards High Speed Downlink
Packet Access or HSDPA which can provide more than four times the downlink
capacity.

REVIEW OF CELLULAR AND WIRELESS COMMUNICATIONS2
Smart Antenna: Smart Antennas provide are responsible for providing another
significant boost for the throughput. These are the adaptive antennas which have
azimuth control, beam and electrical tilt following slow variance in traffic patterns and
also intelligent antennas which can create beams towards specific users and
reduces interferences. They can also come in MIMO or Multiple Input Multiple Output
antenna schemes.
2. Ways to prevent Jamming of WLAN by Bluetooth
Jamming of WLAN networks by Bluetooth services can be reduced in the
several ways. Out of which 5 ways are:
 By bringing Wi-Fi devices and /Wi-Fi routers closer to one another
 By removing barriers like building materials which may cause interferences
such as walls of metal, bulletproof glass, concrete, marble and plaster.
 By avoiding use of wireless devices near devices paired over Bluetooth
 By changing the frequency band of wireless networks from 2.4 GHz (also
used by Bluetooth) to 5 GHz (only supported by Wi-Fi.
 By making the wireless router use different Wi-Fi channels or to scan and find
channels with the least interferences. Usually these routers perform scans
automatically when starting or getting reset.
3. Comparison between Bluetooth and Zigbee Technologies
Bluetooth Zigbee
The frequency range supported by
Bluetooth varies from 2.4 GHz to 2.483
GHz.
The frequency ban supported by Zigbee
is 2.4 all across the world.
There exists 79 Radio Frequency or RF Zigbee only has 16 RF channels.

REVIEW OF CELLULAR AND WIRELESS COMMUNICATIONS3
channels in Bluetooth.
Bluetooth makes use of GFSK
modulation techniques.
Zigbee makes use of BPSK and QPSK
modulation techniques.
Bluetooth involves a maximum of 8 cell
nodes.
Zigbee involves over 65000 cell nodes.
The range of the radio signal of
Bluetooth is 10 meters.
The range of radio signal of Zigbee can
vary from 10 to 100 meters.
4. RTS/CTS Protocols and Terminal Problems
RTS or Request to Send and CTS or Clear to Send are protocols that are
defined as optional mechanisms by 802.11 for addressing frame collisions. RTS and
CTS refer to the additional method that can be used to implement virtual sensing of
carriers in CSMA/CA (Zhang, Cao, Wen, Liang & Zou, 2018). Based on default
configuration 802.11 depends only upon physical carrier sensing which can suffer
from problems of hidden nodes. The packet size threshold is 0-2347 octets.
Generally RTS/CTS frames are not sent if the packet sizes exceed this threshold
(Mathew, Issac & Eng, 2015). Whenever the node wishes to transmit packet size
higher than this threshold, RTS/CTS handshakes get triggered else the data frames
are immediately transmitted.
5. Differences between Hard and Soft Handoff
Hard Handoff Soft Handoff
Hard handoff is defined to be that where
the existing connection needs to be
broken and a new connection is to be
Soft handoff is defined to be that where
the new connection is created before