Hi community,
My project involves the measurement of the Scattering parameters of composites with nanofillers (different percentages of CNT).
In my lab we have the Network Analyzer which I am planning to use for my experiments.
From the available methods( coaxial, through and Free space) I have chosen the later Free space measurements. I have noticed that this measurements are performed with Horn Antennas thus my question is :
Is it possible to use other antennas ( Horn, Loop, Microstrip, Etc) to perform the free space measurements in my samples?
Regards
Sebastian.
I have answered a similar question about why horns are used as standards for antenna measurements, I am re-writing some parts of my answer here. Some of the main reasons horns are used are:
1. Horn antennas are wideband. Microstrip and loop antennas have a narrow bandwidth so you would need different antennas for different frequencies, this can lead to long and tedious measurements.
2. Horn antennas are more robust and once they have their gain standardised they can be used for a long time and many tests. And again since they are wideband, one horn can be used for a large bandwidth. Imagine how many other narrowband antennas you would need to have standardised for gain to achieve the same functionality as a horn.
3. Horns have narrower beamwidths than most other antennas, so less power goes to the sides of the chamber, hence smaller reflections occur. With a wide beamwidth antenna (e.g., loop or microstrip), large reflections will influence your characterisation.