Wireless Technologies Assignment (DOC)

Running Head: WIRELESS TECHNOLOGIES 1
Question 1
Yagi Antennas
Yagi are directional antennas that consist of many parallel elements in single a line and are
usually connected to a receiver with a transmission line, and other components that may not
be connected to the transmitter or receiver. The important component to the Yagi system is
the segments of the flowing currents in the supplementary antenna elements (Electronics,
2017). Yagi antennas operate by retransmitting signals in a considerably different phases to
that of the driven element. In this way, the signals are reinforced in some directions and
negated out in others. Figure 1 below shows a diagram of a yagi antenna.
Figure 1: Yagi Antenna. (Source: Radio Networks)
According to (Wilhite, 2016), Yagi antennas can offer the following advantages and
disadvantages:
Advantages
i) Yagi antennas focus on one direction and therefore have high gain relative for
omnidirectional antennas which make them perfect for getting inferior strength
signals.
ii) They provide high gain

WIRELESS TECHNOLOGIES 2
iii) Their design allows them to filters out nearly all signal noise approaching from
opposite directions which make them a good choice for high demand applications
including telecommunications.
iv) It is easy to mount them on towers and any other structure as well as aim them
compared to arrays.
v) They are cheaper to install and require simple periodic aerials
Disadvantages
i) Limited bandwidth frequency range.
ii) For high gain levels, the antenna will require to be long since antenna gain is limited
to about 6-9 decibels.
iii) Yagi antennas experience signal degradation of electrical gain as you move further
and further away from the frequency range
Horn Antennas
A horn antenna also referred to as microwave antenna consists of metal waveguides that are
shaped like horns to transmit radio waves in form of a beam (Antenna, 2015). Horn antennas
are used for microwave signals that are usually above 300 MHz they accommodate horizontal
and vertical polarities. Basically, horn antennas are used to transfer radio waves from
waveguides into the space or to collect radio waves into a waveguide for reception and used
to measure electromagnetic interference.

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Figure 2: Horn Antenna (Source: The Horn Antenna)
Advantages
i) Can be used as feeder dishes for bigger antennas
ii) Horn antennas suffer little signal loss, and as a result, the directivity of an antenna is
roughly equal to its gain.
iii) Horn antennas are fairly in-built and moderately simple to design and manufacture.
iv) They can be used to transmitting multiple sound waves including acoustic signals
v) Have high antenna gains of up to 25 decibels
vi) High speed data signals and highly efficient
vii) Broad bandwidth spectrums
Disadvantages
i) The gain of horn antennae is prone to high fluctuations rates when frequencies are
low
ii) Their gain of horn antennas frequently increases as the frequency of the system
operation is increased.
Cellular Antennas
A cellular network is a communication system where the last connection is wireless for
example a mobile phone network. Such a network is usually distributed over sections referred
to as cells, and each cell is served by at least one stationary transceiver and base stations

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(Miao, Zander, Sung, & Slimane, 2016). Cellular antennas receive their network coverage
from base stations and use them for both voice and data. In cellular antennas, cells normally
use diverse frequency sets from neighboring cells, to evade signal interference and offer
assured quality services. Figure 3 below shows an illustration of a cellular antennae.
Figure 3: Cellular Antennae (Source: Radio Networks)
Advantages
i) Provides wireless signals in remote localities
ii) Can be implemented to boost wireless sensors in areas where only mobile devices can
work
iii) Cellular networks are robust
Disadvantages
i) Expensive to install,
ii) Difficult to maintain and manage
iii) They can be complex in design
iv) Can suffer electromagnetic interference
v) Require a lot of infrastructure