dBi Of Directivity Research Articles

A Compact High Gain Printed Antenna with Frequency Selective Surface for 5G Wideband Applications

In this article, a frequency selective surface (FSS) based compact wideband printed antenna radiator with improved gain and directivity is proposed for sub-6 GHz 5G wireless networking applications. Due to their inherent property of possessing spatial filtering characteristics, FSSs are attracting the interest of researchers. An approach for increasing the gain and the directivity by integrating a band pass FSS on a compact built patch antenna radiator is proposed here. The architecture equations for designing the band pass FSS using double square loop geometry are defined. The printed patch antenna radiator (PAR) and a double square loop frequency selective surface (DSLFSS) are designed and integrated. The simulation results are verified using the results from the measuring setup. The output response is giving a fractional bandwith of 19.14% with 5.5 dBi gain and 6.2 dBi of directivity and thus makes it the good choice for 5G applications.

Array of stacked leaky-wave antennas in groove gap waveguide technology

The design of an array of stacked leaky-wave antennas in groove gap waveguide technology is presented in this work. The proposed array is formed by simply stacking a number of leaky-wave antennas one on top of the other and feeding all of them with uniform amplitude and phase. The inter-element distance is studied in order to avoid grating lobes and to maximize the directivity. A feeding network based on vertical coupling is designed, where the input port feeds the bottom element, and then the energy is equally coupled to the other elements. To obtain maximum directivity the phase is corrected at each element separately. The central frequency of the proposed design is 28 GHz. With this technique of stacking the elements a pencil beam is achieved, i.e. the radiated energy is focalized in the two main planes. The designed array with four elements achieves an enhancement of + 5 dB, reaching 24.5 dBi of directivity in comparison to 19.6 dBi of directivity of the single leaky-wave antenna made in this technology. A prototype is manufactured and measured and its results are presented and compared with the simulations.

Mutual Coupling Reduction of MIMO Antenna for Satellite Services and Radio Altimeter Applications

Ground irregularities also known as defected ground structures (DGS) is a freshly presented innovatory way in designing of patch antennas to boost up the performance of antenna constraints. This study presents a novel proposal of ground irregularities or defected ground structure is proposed for suppression of mutual coupling effects among 2x1 multiple input multiple output patch array designed on Roggers Duroid 5880. The two adjacent M shape structures surrounding Dumbbell Shaped structure and sandwiched between Dumbbell shape patterns showed the significant level of surface wave suppression up to -42dB while maintaining the gain of 4.7dB and 5.6dBi of directivity. The patch array operates at 4 to 4.3GHz for Fixed and Radio satellite services (FSS) and (RSS) and radio altimeter application systems.

High Gain and High Directive of Antenna Arrays Utilizing Dielectric Layer on Bismuth Titanate Ceramics

A high gain and high directive microstrip patch array antenna formed from dielectric layer stacked on bismuth titanate (BiT) ceramics have been investigated, fabricated, and measured. The antennas are designed and constructed with a combination of two-, four-, and six-BiT elements in an array form application on microwave substrate. For gain and directivity enhancement, a layer of dielectric was stacked on the BiT antenna array. We measured the gain and directivity of BiT array antennas with and without the dielectric layer and found that the gain of BiT array antenna with the dielectric layer was enhanced by about 1.4 dBi of directivity and 1.3 dB of gain over the one without the dielectric layer at 2.3 GHz. The impedance bandwidth of the BiT array antenna both with and without the dielectric layer is about 500 MHz and 350 MHz, respectively, which is suitable for the application of the WiMAX 2.3 GHz system. The utilization of BiT ceramics that covers about 90% of antenna led to high radiation efficiency, and small-size antennas were produced. In order to validate the proposed design, theoretical and measured results are provided and discussed.