COMSOL Antenna Simulations Assignment

Antenna Simulations

Antennas are necessary components of any wireless communication system, enabling both the transmitting and receiving of EM carrier waves. This COMSOL simulation lab will investigate one of the most common antennas, the electric dipole, and some of its variants.

As with all of the COMSOL labs, please write up your lab report as you go along, copying and pasting all relevant diagrams. Make sure that you label all figures and include sufficient text to answer completely all of the questions below. Please reference any material (text, figures, etc.) that you extract from elsewhere.

The deadline for submission of your report for this lab will be 23:59 on Tues in week 11. Please submit your report on LC as a single pdf (convert Word documents into pdfs).

Please use the guidance notes provided for setting up the electric dipole simulation of part (a) below; the same model can then be used for the other parts of the lab.

(a) Electric dipole antenna (10 marks)

Estimate the length required for a half-wave electric dipole antenna for transmitting/receiving EM waves at 800 MHz (this is in the UHF bandwidth of 470 to 860 MHz, used for UK TV transmissions). Show the COMSOL sketch of the antenna geometry, the mesh generated, the simulated electric field around the antenna and its resulting far-field radiation pattern. Hence estimate the antenna directivity and comment on the result.

(b) Monopole antenna (6 marks)

Adapt your antenna from part (a) to include a ground plane to form an 800 MHz electric monopole antenna. Again, show the COMSOL sketch of the antenna geometry, the mesh generated, the simulated electric field around the antenna and its resulting far-field radiation pattern. Hence estimate the antenna directivity and comment on the result. Compare and contrast the radiation pattern of this antenna with that of the electric dipole of part (a).

(c) Antenna arrays (3 marks)

With the aid of suitable diagrams, describe the benefits that antenna arrays have over single element antennas, with their applications.

(d) Electric dipole array (6 marks)

Adapt the half wavelength dipole antenna of part (a) to form a 3 element linear dipole array, with separations of ?0/2. As in parts (a) and (b), show the COMSOL sketch of the antenna array, the mesh generated, the simulated electric field around the antenna array and its resulting far-field radiation pattern. Estimate the array’s directivity and compare/contrast the array’s radiation pattern with that of the single electric dipole of part (a).