Nadeem Ashraf

28/38-GHz dual-band millimeter wave SIW array antenna with EBG structures for 5G applications

The design of linearly polarized dual-band substrate integrated waveguide (SIW) antenna/array operating at Ka-band is proposed. The single antenna element consists of a SIW cavity with two longitudinal slots engraved in one of the conducting planes. The longer and shorter slots are resonating at 28 GHz and 38 GHz, respectively. Only the simulated results are presented. All simulations have been carried out using industry-standard software, CST Microwave Studio. For single antenna element, an impedance bandwidth (S11 <; -10 dB) of 0.45 GHz (1.60 %) and 2.20 GHz (5.8 %) is achieved with the maximum gain of 5.2 dBi and 5.9 dBi at 28 GHz and 38 GHz, respectively. To achieve high gain, a horizontally polarized linear array of four elements (1 × 4) is designed. For the antenna array, a microstrip lines feed network is designed using 3-dB wilkinson power divider. At 28 GHz and 38 GHz, the impedance bandwidth is 0.32 GHz (1.14 %) and 1.9 GHz (5%) having maximum gain of 11.9 dBi and 11.2 dBi, respectively. A low loss/cost substrate, RT/Duroid 5880 is used in the proposed designs.

Substrate integrated waveguide antennas/array for 60 GHz wireless communication systems

A single layer substrate integrated waveguide (SIW) antennas/array for high speed 60 GHz communications, are presented. SIW based single antenna element and then two 1× 4 array are designed. Two types of feeding networks are designed for the array; a classical approach of microstrip lines and complete SIW based design. A comparison between the resulted radiation characteristics is performed. The back radiation phenomena is found to be high in the case of microstrip lines feeding network. This effect is minimized by introducing a complete SIW based feeding network. The gain of SIW single antenna element is 6 dBi having radiation efficiency 80 %. A gain of 11.2 dBi is achieved for each array design and an efficiency of 76 % and 73 % is achieved for 1×4 array with microstrip feeding network and a complete SIW feeding network, respectively. A low loss/cost substrate, RT duroid 5880 is used in the proposed designs.

A DR Loaded Substrate Integrated Waveguide Antenna for 60 GHz High Speed Wireless Communication Systems

The concept of substrate integrated waveguide (SIW) technology along with dielectric resonators (DR) is used to design antenna/array for 60 GHz communication systems. SIW is created in the substrate of RT/duroid 5880 having relative permittivity and loss tangent . H-shaped longitudinal slot is engraved at the top metal layer of the substrate. Two pieces of the DR are placed on the slot without any air gap. The antenna structures are modeled using CST Microwave Studio and then the results are verified using another simulation software HFSS. Simulation results of the two designs are presented; first a single antenna element and then to enhance the gain of the system a broadside array of is presented in the second design. For the single antenna element, the impedance bandwidth is 10.33% having a gain up to 5.5 dBi. Whereas in an array of elements, the impedance bandwidth is found to be 10.70% with a gain up to 11.20 dBi. For the single antenna element and antenna array, the simulated radiation efficiency is found to be 81% and 78%, respectively.

A dielectric loaded millimeter wave antenna array for 60 GHz communication systems

A Dielectric loaded millimeter wave antenna array of 1 × 4 elements fed by slotted substrate integrated waveguide for 60 GHz communication systems is presented. Only slotted SIW design cannot provide a wide bandwidth and hence to achieve wide bandwidth the concept of dielectric loading is adopted. The cumulative effect results in wide bandwidth. This design uses a complete SIW feed network to minimize the effect of back radiations. The results show an impedance bandwidth of 10.50 % around 60 GHz, having a gain up to 10.60 dBi, and an estimated efficiency of 75 %. The designs are simulated in CST Microwave Studio and verified in HFSS simulator.

Millimeter wave antenna based on substrate integrated waveguide technology for 60-GHz communication system

A millimeter wave antenna is presented for 60 GHz communication using substrate integrated waveguide (SIW) technology along with dialectic resonators (DR). A very thin substrate of RT duroid 5880 having permittivity εr= 2.23, loss tangent tan δ = 0.003 is used. Same material used for the DR having thickness 0.79 mm. H-shape slot in engraved at the top ground plane that acts as a source-radiating aperture. Two pieces of DR are placed on the top metal layer of the substrate to achieve wider bandwidth. The antenna structure is modeled using CST Microwave Studio. The simulated impedance bandwidth of the antenna is 10.33 % having a gain up to 5.5 dBi. The radiation efficiency of the antenna is found to be 81 %. The results are verified by using another simulation software HFSS and found to be in good agreement.

BCB-Si based antenna for millimeter wave applications

In this paper a benzocyclobutene (BCB) - silicon (Si) based wide band antenna for millimeter wave applications is presented. The antenna consists of multilayer with one layer of BCB and the remaining three layers of Si. The results of simulations show that the antenna provides an S11 <; -10 dB bandwidth of 9.7 GHz (17%) starting from 51.5 GHz to 61.2 GHz around 57 GHz central frequency. The antenna provides a maximum gain of 8.9dBi with an efficiency of 70%.