### Recent Question/Assignment

Before 10am on:
22/03/2019
20 working days after deadline (L4, 5 and 7)
15 working days after deadline (L6)
10 working days after deadline (block delivery)
05/04/2019
Unit title & code Digital, Microwave and Optical Communications (CIS117-6)
Assignment number and title One – Digital , Microwave and Optical Communications
Assessment type Portfolio
Weighting of assessment 100%
Unit learning outcomes 1.Demonstrate a systematic understanding of the fundamental underpinning scientific principles of digital, microwave and optical communications and the corresponding system components.
2. Criticallyanalyse and assess digital, microwave and optical communication technologies, techniques, models and system design and performance
What am I required to do in this assignment?
You are required to complete the exercises that outlined below. There are exercises for each of the three components: Digital, Microwave and Optical Communications. The exercises are also included below for completeness. Each exercise has a number of marks associated with it, and you will need to answer all of the sub question for each component.
Digital communications
Q1 a) Explain the concept of entropy (information theory) with respect to digital communications (5 marks)
Q1 b) Using a diagram, explain the key components of a digital communications system (10 marks)
Q2 a) What is digital modulation used for within a digital communications system? (5 marks)
Q2 b) Explain three different ways of modulating a signal when only one degree of freedom is modulated
(10 marks)
Q3) Consider a DMS where output is generated from an alphabet {a,b,c,d,e,f,g,h} with respective with probabilities {0.25, 0.1, 0.02, 0.05, 0.25, 0.03, 0.25, 0.05}.
a) Design a Huffman code and sketch the corresponding coding tree. Explain the codewords for each character in the alphabet (10 marks)
b) Calculate the average length of the codeword if the Huffman code you generated (5 marks)
c) Calculate the efficiency of your Huffman code (5 marks)
Q4) Design a Shannon-Fano code and sketch the corresponding coding tree where the alphabet is {a,b,c,d,e,f} with corresponding probabilities {0.5, 0.1, 0.05, 0.05, 0.25, 0.25} (10 marks)
Microwave communications
Q1) Antennas play a vital role in the performance of wireless communications systems. Microstrip patch
antennas are very widely used in wireless applications due to their inherent features of simple design,
low complexity, ease of fabrication and low cost to meet the design requirements.
The objective of this assignment is the design of a microstrip patch antenna for a practical Wireless
Local Area Network (WLAN) application operating at ISM band in the range of 2.45 GHz. The antenna
is excited using a microstrip transmission line.
a) The important dimensions that need to be optimised include length and width of the ground plane,
patch and feed, and width and length of the two matching cuts on each side of the feed.
1. You need to design an antenna that needs to be matched such that the resonance frequency
is:
fr = 2.45GHz + (last 3 digits of your student ID / 2)Mhz
For example, if your student ID number is 1322350 then the antenna working frequency should
be as follows:
? 350 ?
f r = 2.45GHz + (300/2)MHz
= 2.45GHz +150MHz = 2.6GHz
(20 marks)
Optical communications
You have to design a Radio-over-Fibre System for a four storey hospital building that has 20
rooms per floor. The communication link is to be used for a wide variety of functions including
locating physicians, requesting test results, checking patient records of patients and calling for
mobile test data.
a) Show a block diagram of your designed system, justifying your selection of all the
components. Clearly define all assumptions.
(10 marks)
b) Analyse your system performance using excel sheet to demonstrate that the link budget of
the designed system meets the requirements.
(10marks)
c) Implement the system in Optiwave and analyse its performance.
(15 marks)
d) Compare the performance of the designed system with simulation results.
(5 marks)
e) What is the maximum number of channels that your system can accommodate? (10 marks)
Is there a size limit?
Yes, the overall report should not exceed 5000 words
What do I need to do to pass? (Threshold Expectations from UIF)
1. Select appropriate solutions from candidates when designing key system components
2. Analyse and evaluate the feasibility of your optical link prototype using suitable methods.
3. Design an optical link using appropriate software tools and laboratory equipment
4. Analyse and critically evaluate the feasibility of your prototype using suitable methods
5. Design and prototype a microwave component using laboratory equipment
6. Effectively and professionally present ideas and solutions
How do I produce high quality work that merits a good grade?
You need to demonstrate clear knowledge and understanding of the three communication system types, as well as providing evidence of analysis and justification of the approaches you have chosen. You must clearly explain the choices you have made and back these up using appropriate theory.
How does assignment relate to what we are doing in scheduled sessions?
The assignment builds upon the theory presented in class and helps you to put the theory into practice using appropriate examples and measurements.
How will my assignment be marked?
Your assignment be marked according to the threshold expectations and the criteria on the following page.
Pass – 40-59% Commendation – 60-69% Distinction – 70%+
1
Select appropriate solutions from candidates when designing key system
Explain and justify the solutions you have made clearly articulating the benefits
Critically evaluate the design choices you have made and clearly explain why you have chosen your approach
2
Analyse and evaluate the feasibility of your optical link prototype using suitable methods.
Critique you chosen design and clearly identify improvements on the basis of the analysis undertaken
Critically evaluate the appropriateness of your chosen system and demonstrate its effectiveness compared to other designs
3
Design an optical link using appropriate software tools and laboratory equipment
Evaluate the effectiveness of your chosen design making use of appropriate data for the analysis
Compare and contrast your chosen design clearly evaluating effectiveness and making suggestions for future improvements,
4
Analyse and critically evaluate the feasibility of your prototype using suitable methods
Compare and contrast your chosen prototype making suggestions for improvements
Propose how your prototype compares to commercially available solutions.
5
Design and prototype a microwave component using laboratory equipment
Justify the design choices of your designed prototype and explain how it addresses the problem
Critically evaluate the performance of your approach and explain how it compares against commercial solutions
6.
Effectively and professionally present ideas and solutions
Provide a professional quality set of solutions with clear justifcations and rationale.
Outstanding quality report with professional presentation, high quality outputs and very well explained conclusions