Hi There,
in order to increase antenna gain, meta-material lens is getting popular these days.
I wonder, if we consider size and possible gain of the antenna (limited to size -see the formula in attachment)
- then for a fix size is it possible to increase antenna gain using meta-material lens?
when we apply meta-material lens the overall size of the antenna increase. will it be possible to develop antenna (without meta lens) of bigger size to get similar gain as with using antenna with meta lens?
kindly scholars having experience with meta-material antenna help to get some insight into the size vs gain of antenna using meta-material.
Thanks
"No" is the accurate and short answer. Metamaterial lenses can reduce the volume or weight of an antenna, and can increase its directivity (make its beam narrower) but cannot make it have more gain than the standard formula that you have included. The gain may be lower, because there may be extra loss in the metamaterial. One thing that does not appear in the formula you have is gain due to length, such as in a linear dipole array (TV antenna) or a dielectric rod antenna. In these antennas the energy spreads out around the antenna as it travels along it so that by the far end it occupies the same area that would be in the usual directivity formula (the gain formula without the efficiency term), but the antenna itself does not have that area. The antenna slows down the middle of the wave so that the phase front remains more planar over the length of the antenna than it would do without the antenna there, so that most or all of the gain associated with the area of the spread out power can be acieved.
In short the answer is no. For a given aperture size you are stuck with the diffraction limit. (the lambda / pi D term). A metamaterial lens may make it practical to use a larger aperture than would be possible with standard optics. (Cheaper, simpler, fewer components) and you can win that way. However, at the same aperture diameter the diffraction limit is the same. There are tricks for getting beyond the diffraction limit such as MIMO and a metamaterial lens might make doing those tricks more convenient or practical, but there is nothing fundamentally different. Anything you can do with one you can, in principle, do with the other.
Thanks Mike Albert and Malcolm White for the short and to the point the point answer.
- Badges
- Science topic
- Similar topics
- Analytical Chemistry
- Extraction