Analysis of Antennas and Multiplexing Techniques in Wireless Networks

This assignment delves into the realm of wireless communication, offering a comprehensive analysis of different antenna types and multiplexing techniques. The solution begins by categorizing antennas based on their wave propagation characteristics, focusing on directional, semi-directional, and omni-directional antennas. It then examines the Yagi, horn, and cellular antennas, highlighting their strengths, weaknesses, and specific applications. The assignment further explores the future of wireless communication, emphasizing the potential of smart antennas. The second part of the assignment compares and contrasts two multiplexing techniques, CDMA and FDMA, detailing their operational principles and suitability for wireless networking. The solution provides a detailed comparison of these techniques, emphasizing their differences. Finally, the assignment presents an analysis of advanced wireless technologies, including their applications, strengths, and weaknesses.

Running head: ASSIGNMENT
Assignment
[Student Name Here]
[Institution’s Name Here]
[Professor’s Name Here]
[Date Here]

ASSIGNMENT 2
Question one
Antennas are devices that couple moving electromagnetic waves to and from electronic
circuits using conductors that are either apertures or wires (MIT, 2004). Now, these antennas
are categorised based on how they propagate waves, which defines the different types of
antennas used today i.e. directional, semi-directional and Omni-directional
1. Yagi antenna – one of the most popular and successful RF antenna used. It’s a
directional antenna, thus it propagates RF waves in one direction which is associated with
high gains and directivity. It’s used in areas that require these characteristics e.g. television
reception.
Strengths:
a. Low-cost design.
b. High gains and directivity.
c. Simple to install and use.
Weaknesses
a. For high gain levels, a long structure is required.
b. Its gain is limited (radio-electronics, 2017).
2. Horn antenna – a directional antenna that is popular for transmitting ultra-high
frequency (300MHz-3GHz) signals. Its name comes from its design, where a horn like
structure, flares out to radiate signals enabling it to have high gains (Rouse, 2017).
Strengths:
a. It can operate at a wide range of frequencies and bandwidth.
b. High gains.

ASSIGNMENT 3
c. Simple construction
Weaknesses
a. It requires lengthened structure to operate effectively.
b. Complex to install.
3. Cellular antenna – An Omni-directional antenna that can propagate signals in all
direction and is common in mobile devices such as mobile phones, tablets and vehicles. It’s
usually small in size which facilitates its functionalities (Carr, 2012).
Strengths
a. Can amplify and operate in all directions.
b. Optimal boosting capabilities.
Weaknesses
a. Minimal gains.
b. Short coverage distance.
Future of medium and long distance wireless communication
Cellular antennas seem to have laid a solid foundation for mobile devices which marks them
as the future of wireless communication. However, their low gains and coverage limit their
functionalities, which necessitates the need for booster towers unlike the directional antennas
highlighted above. Therefore, cellular antennas will require modifications in order to operate
beyond their current applications. In light of these outcomes, the future may experience smart
antennas designed as hybrids of both directional and Omni-directional antennas.

ASSIGNMENT 4
Question two
CDMA – Code division multiple access & FDMA – Frequency division multiple access.
Both are multiplexing techniques that were designed to meet a telecommunication challenge,
that of assigning bandwidth to consumers i.e. the signals.
CDMA: In this technique, the entire communication bandwidth is shared among many users
by assigning them unique identification codes. In essence, the users are represented by
multiple signals that are propagated in common channels, thus are uniquely identified by the
codes. Now, the signals outlined above are tagged with the said codes during transmission
and are used to separate the signals at the reception stage (corps, 2000). Consider the CDMA
standard IS-95, which uses the 1.225 bandwidth range. This standard uses 64 Walsh codes to
propagate signals.
FDMA: In this technique, the entire band of frequencies are shared among many users by
dividing it into multiple radio frequency channels. Furthermore, non-overlapping frequencies
are used so as to transfer each signal uniquely to its destination. A good example is the GSM
model where the 25 MHz frequency band is split into 124 carriers each having an estimated
bandwidth of 200 kHz.
CDMA FDMA
A common frequency is used. Channel is usually idle when not in use.
Every user has a unique pseud-code. Suitable for analogue applications.
Each receiver must know the code of the
transmitter.
Filtering is needed to eliminate
interferences.
Only desired codes are detected, the rest
appear as noise.
Narrow band is used
(Zahra, 2015)

ASSIGNMENT 5
References
Carr, J. (2012). Directional or Omnidirectional antenna? Joe Carr's Radio Tech-notes,
Retrieved 14 August, 2017, from: http://www.dxing.com/tnotes/tnote01.pdf.
corps, W. (2000). FDMA vs. TDMA vs. CDMA. Connecting Wireless, Retrieved 14 August,
2017, from: http://wirelessapplications.com/pdf/lf/FD_TD_CDMA.pdf.
MIT. (2004). Chapter 3: Antennas. MIT, Retrieved 17 August, 2017, from:
https://ocw.mit.edu/courses/electrical-engineering-and-computer-science/6-661-
receivers-antennas-and-signals-spring-2003/readings/ch3new.pdf.
radio-electronics. (2017). Yagi Antenna / Yagi-Uda Antenna. Antennas and propagation,
Retrieved 14 August, 2017, from:
http://www.radio-electronics.com/info/antennas/yagi/yagi.php.
Rouse, M. (2017). Horn antenna. Research gate, Retrieved 17 August, 2017, from:
http://searchmobilecomputing.techtarget.com/definition/horn-antenna.
Zahra. (2015). FDMA-TDMA-CDMA. Multiple access techniques in wireless
communication, Retrieved 16 August, 2017, from:
https://www.slideshare.net/SammarKhan2/fdmatdmacdma.