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A square dielectric resonator element (SDR) with a defected ground structure (DGS) is investigated. The proposed DGS is composed of two rectangular slots connected by two transverse slots and is placed in the ground plane. It is fed by a strip line through the substrate layer. The objective of this structure is to design dielectric resonator band- stop filter (DRF) and enhance the performance in terms of better insertion loss and increased bandwidth. The DRF has been fabricated and measurements are taken. The results for band- stop filter show a cut-off frequency of 2.25 GHz, transmission loss of 2 dB and the 3-dB bandwidth ranges from 1.4 to 2.64 GHz. The effect of the transverse slot width on the filter response curve is studied. The same structure is modulated to be frequency reconfigurable DRF for achieving frequency agility by using ideal metallic switches. The cut-off frequency is shifted by 1 GHz, the 3-dB bandwidth by 1.5 GHz, while the transmission loss is decreased by 0.75 dB. Finally, the effect of loading SDR with metal plate is investigated. This structure combines the dielectric resonator antenna and the DRF to propose dielectric resonator antenna filter (DRAF), this structure is used to miniaturize the global-positioning-system receivers that contain both the antenna and filter. The DRAF has been fabricated and measured, it has 3-dB pass bandwidth of about 1 GHz. Factors such as return loss, insertion loss, radiation pattern and mutual coupling of DRAF are calculated using Finite element method. Comparison of calculated and measured factors of DRAF shows a good agreement. [ABSTRACT FROM AUTHOR]

A square dielectric resonator element (SDR) with a defected ground structure (DGS) is investigated. The proposed DGS is composed of two rectangular slots connected by two transverse slots and is placed in the ground plane. It is fed by a strip line through the substrate layer. The objective of this structure is to design dielectric resonator band-stop filter (DRF) and enhance the performance in terms of better insertion loss and increased bandwidth. The DRF has been fabricated and some measurements are taken. The cutoff frequency of the band-stop filter is 2.25 GHz, with transmission loss of 2-dB. The 3-dB of the band-stop filter is 1.24 GHz. The effect of the transverse slot width on the filter response curve is studied. The same structure is modulated to be frequency reconfigurable DRF to achieve frequency agility by using ideal metallic switches. The cut-off frequency is moved to 1GHz, and the 3-dB bandwidth in 1.5 GHz, while the transmission loss is decreased by 0.75 dB. Finally, the effect of loading SDR with metal plate is investigated. This structure combines the dielectric resonator antenna (DRA) and the DRF to propose dielectric resonator antenna filter (DRAF), this structure is used to miniaturize the global-positioning-system receivers that contain both the antenna and filter. The DRAF has been fabricated and measured, it has 3-dB pass bandwidth in 1GHz. Factors such as return loss, insertion loss, radiation pattern and mutual coupling of DRAF are calculated using finite element method (FEM). Comparison of calculation and measurement factors of DRAF shows a good agreement. [ABSTRACT FROM AUTHOR]

Linearly polarized transparent dielectric resonator antenna (TDRA) transmitarray is designed and investigated for 12 GHz applications. A parametric study on the effect of solar-cell position on the radiation characteristics of the TDRA transmitarray. The unit cell consists of two TDRAs arranged back-to-back with one on either side of a perfect transparent conducting ground plane. The waveguide model is used to calculate the required compensation phase of each cell in the transmitarray. The radiation characteristics of a 9 × 9 linearly polarized transparent transmitarray antenna are investigated in different positions of solar-cell with respect to the DRA. The peak gain is 20.22 dB with a 1-dB gain bandwidth is more than 2 GHz (16.67%) for the TDRA transmitarray without solar-cell. The solar-cell is integrated with TDRA transmitarray with different positions for small satellite applications. The radiation characteristics of the transmitarray are simulated and calculated using the finite integral technique (FIT). [ABSTRACT FROM AUTHOR]

In this paper, reflectarrays mounted on or embedded in cylindrical and spherical surfaces are designed, analyzed, and simulated at 11.5 GHz for satellite applications. A unit cell consists of a square dielectric resonator antenna (DRA) mounted on or embedded in metallic conformal ground plane is investigated. The radiation characteristics of the designed reflectarrays are investigated and compared with that of planar reflectarray. A 13x13 planar reflectarray antenna on the x-y plane was designed. By varying the length of the DRA element between 2mm and 6.2mm a full range from 0°to 360° phase shift can be obtained. The size of each element is equivalent to a compensation phase shift. A maximum directivity of 24.3 dB was achieved while the side lobes were below -12:94 dB in E-plane and -15:79 dB in the H-plane for planar reflectarray. A Full-wave analysis using the finite integration technique (FIT) is applied. The results are validated by comparing with that calculated by transmission line method (TLM). [ABSTRACT FROM AUTHOR]