125 – antenna project

You are required to complete an individual assignment for the module Antennas and Wave Propagation (ELEC 20006.2). The work must be accurate, well-structured, and academically sound, as it will be evaluated based on understanding, analysis, and presentation.

### General Requirements:

– Answer all questions clearly and correctly.

– Show all steps in calculations.

– Use proper academic writing in English.

– Include suitable references using a standard referencing style (e.g., IEEE or Harvard).

– Ensure the report is neatly formatted with correct grammar and spelling.

– Include diagrams where required (especially for transmission lines and Smith Chart).

– Provide brief reflections where applicable.

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### Task Details:

#### 1. Quarter-Wave Line as an Impedance Inverter

Explain why a quarter-wave transmission line is called an impedance inverter.

– Include the mathematical expression.

– Explain the concept clearly.

– Provide real-life applications (e.g., RF circuits or antenna systems).

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#### 2. Copper and Insulators in Transmission Lines

Explain how copper and insulating materials are used in practical transmission lines.

– Describe their roles.

– Provide examples such as coaxial cables or twisted pair cables.

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#### 3. Propagation Velocity Calculation

Given:

– ( R = 40 , Omega/km )

– ( L = 0.7 , mH/km )

– ( C = 50 , nF/km )

– ( G approx 0 )

– Frequency = 1 MHz

You are required to:

– Calculate the propagation velocity using the correct formula.

– Show all steps clearly.

– Provide a short reflection on the result (compare with speed of light and explain).

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#### 4. Input Impedance Analysis

Apply the input impedance formula for transmission lines.

– Compare two different cases (e.g., short line vs quarter-wave line).

– Explain which case is suitable for impedance matching and why.

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#### 5. Quarter-Wave Transformer Design

Given:

– ( Z_0 = 300 , Omega )

– ( Z_L = 180 , Omega )

– Frequency = 400 MHz

– Length = 22.5 cm

You must:

– Calculate the required characteristic impedance of the quarter-wave transformer.

– Draw the equivalent circuit.

– Illustrate and explain the standing wave pattern.

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#### 6. Transmission Line Analysis using Smith Chart

For a lossless transmission line:

– Calculate the following:

1. Reflection coefficient

2. VSWR

3. Input impedance

4. Input admittance

5. Distance to first minimum

6. Distance to first maximum

– Solve analytically and verify using the Smith Chart.

– Include a scanned copy or clear image of the Smith Chart with proper markings.

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### Additional Requirements:

– The report must be logically structured with headings and subheadings.

– Include figures, equations, and explanations where necessary.

– Ensure all answers demonstrate clear understanding and correct application of theory.

– Add a reference list at the end of the report.

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### Submission Expectation:

The final work should be complete, accurate, and ready for submission without requiring further corrections.