The mode resonating at 94 GHz is generated within the CDRs and a 3 GHz impedance bandwidth is achieved at center frequency of 94 GHz.The simulated antenna gain is 7.8 d B, with a radiation efficiency of about 40%.The walls of the resonator are partially transparent to radio waves, allowing the radio power to radiate into space.
So these antennas can have lower losses and be more efficient than metal antennas at high microwave and millimeter wave frequencies.
An antenna like effect is achieved by periodic swing of electrons from its capacitive element to the ground plane which behaves like an inductor.
Whilst in antenna-coupled MIM and Schottky diodes the detection mechanism is such that antenna resonant currents are being rectified by the diode located at the feed of the antenna leading to a resultant dc current component.
Dielectric resonator antennas (DRAs) operating in the MMW band possess many merits that make them preferable in antenna-coupled sensor configurations.
DRAs, operating in the MMW band, have shown high radiation efficiencies as compared to printed metallic antennas.
This is mainly due to the absence of conductor and surface wave losses which are greatly dominant in printed metallic antennas.
The red dotted area in Figure 3 is zoomed and shown in Figure 4 for a more detailed view of excitation slot, CPW feeding lines, and bolometer resistor placement.
The CPW line is divided into two equal parts by introducing a gap of mm for bolometer resistor placement.
A dielectric resonator antenna (DRA) is a radio antenna mostly used at microwave frequencies and higher, that consists of a block of ceramic material of various shapes, the dielectric resonator, mounted on a metal surface, a ground plane.
Radio waves are introduced into the inside of the resonator material from the transmitter circuit and bounce back and forth between the resonator walls, forming standing waves.