Description of Assessment Task:

In this assignment you will develop and test a Matlab program for plotting antenna radiation patterns and antenna parameters calculation. You will be given 4 data files in .csv format that represent results for measured radiated power of an antenna versus azimuthal angle φ and elevation angle θ.

- File Phi.csv contains a column of azimuthal angles φ from 0-360 degrees.
- File P_phi.csv contains a column of measured radiated power in Watts in the direction of angle φ with matching index, e.g. fifth row in P_phi.csv (P(5) value) corresponds to fifth row in Phi.csv (φ(5) value).
- File Theta.csv contains a column of elevation angles θ from 0-360 degrees.
- File P_theta.csv contains a column of measured radiated powers corresponding to θ angles.

You are required to analyse the data by calculating antenna parameters and visually representing radiation patterns in the report.

Step 1: Import files

Copy all required files to the Matlab folder on the computer. Files need to be in the same Matlab folder as the program you run.

Write code to import the contents of the .csv files into Matlab. Import files for azimuthal angles φ and corresponding powers first. (Alternatively use import button in Matlab).

Step 2: Preliminary parameter calculations

Find the angle in direction of which radiation is maximum. Normalise powers of radiated field to maximum radiated power. Convert angles to radians.

Step 3: Plot antenna radiation pattern

Plot radiation pattern for powers in dB versus azimuthal angle φ. You can use plot_dB.m Matlab program attached in your assignment. Program can be opened and edited in notepad if necessary. Program works similar to inbuilt Matlab polar plot command and expects angle in radians and power in normalised ratio form (not dB).

polar_dB(angle,power,rangedb,increments,rays), where angle and power are names of your actual variables for angles and powers, rangedb, increments, rays parameters define minimum polar radius value (e.g. min power in dB) and grid line spacings.

Write code to export image into a .jpg file. (Alternatively use save button in Matlab).

Step 4: Parameter calculations

Write code to calculate P ratio in dB and calculate the beamwidth of the antenna in horizontal plane. If exact required power level match is not possible due to discrete data in .csv file, use the nearest available value in.csv file for calculations. Include formula and/or explanation for each calculated parameter. (Alternatively find required data from
.csv files for lower mark).

Write code and calculate front to back ratio of the antenna in dB in horizontal plane.

Write code and calculate number of antenna side lobes, direction of maximum radiation and powers in dB radiated into direction of each side lobe in horizontal plane. (Alternatively find side lobe levels and directions from .csv files for lower mark).

Step 5: Repeat steps for elevation angles

Repeat steps 1 to 4 for vertical plane (versus elevation angle θ).
Step 6: Export result to a file

Export results of your calculations with text description for each result into a .csv file.

Step 6: Discuss the results

Discuss in the report antenna's properties based on what you have found from calculations and visualisation. Attach your Matlab code to your report as appendix.

Attachment:- csv files.zip