Available solutions include ellipsoidal reflector antennas and pyramidal/conical horns with a
dielectric lens in front of the antenna aperture, but they are quite bulky and heavy antennas at the microwave band.
The proposed structure is composed by 2 x 2 array of slot-ring antennas covered by a hemispherical
dielectric lens.
Metamaterials used for the
dielectric lens reduce its weight by about 90
In Section 2, the effective parameters of the proposed material are retrieved, the reasons for gain improvement by the proposed material are investigated, and for an end-fire antenna, the enhanced gain by a
dielectric lens and the ML-based material are compared.
To compensate this issue, a wideband
dielectric lens is placed in the aperture of each element.
Le Coq, "Flat-shaped
dielectric lens antenna for 60-GHz applications," IEEE Trans.
It can be obtained using a planar patch array [1,2], a slotted rectangular waveguide [3], a horn with metal plate lens [4,5] or with a
dielectric lens. In the latest case, the
dielectric lens can be placed in front of the horn [6] or inserted in the horn aperture [7, 8].
where N is normal to the hyperbolic surface, [p.sup.i] is the wave vector of the incident wave and n is the refractive index of the lens material which is normally a constant and is greater than unity for natural
dielectric lens. The wave vector of the incident waves, for both LCP and RCP, is given as:
The research used an in vitro exposure system developed by NTT DoCoMo that incorporated a horn antenna and
dielectric lens in an anechoic chamber.
It consisted of a feed antenna and a
dielectric lens that focuses microwave energy onto the sample.
The third method is parasitic ellipse and
dielectric lens. These two can increase the gain at a high frequency [28, 29].