Various designs of a dual-band antenna constructed from textile fabrics for use in a wearable application are evaluated using XFdtd. The base antenna design of a rectangular patch with a tuning via are evaluated for antenna performance and Specific Absorption Rate (SAR) exposure. The base design is made into various arrays for determining an optimal configuration for a MIMO application. The antennas are also tested in bending situations which might arise in a body-worn application.
A 60 GHz antenna array design is simulated in XFdtd to demonstrate suitability for use on wireless Virtual Reality headsets. The antenna array is comprised of elements each containing two patches and a parasitic element. The resulting array produces a fan beam which may be steered by varying the phasing between the elements resulting in broad coverage. The final design is simulated mounted on a section of a virtual reality visor.
This example uses XFdtd to simulate the performance of a low cost, chipless RFID system. The RFID tag is comprised of two ultrawide band monopole disk antennas mounted in a cross-polarized configuration combined with a microstrip line adjacent to six varying size spiral resonators which each represent a single bit in the RFID tag code. The system is validated using two cross-polarized log periodic dipole arrays as the send and receive devices.
This example is a more complete device for 28 GHz beamforming for 5G networks and includes an 8x8 patch antenna array, 1 to 8 power dividers and a Rotman lens initial stage. The design of the Rotman lens is performed using Remcom’s Rotman Lens Designer® (RLD) software, which produces a CAD version of the device for use in XFdtd®. In XFdtd, a set of eight 1 to 8 Wilkinson stripline power divider networks is designed to act as the connection between the Rotman lens and the antenna array. The performance of each stage is simulated and evaluated.
Series-fed patch elements forming an array are simulated to demonstrate antenna performance and beamforming including S-parameters, gain, and effective isotropic radiated power (EIRP) at 28 GHz. Beam steering is performed in one plane by adjusting the phasing at the input ports to each of eight elements.
The millimeter wave frequencies being planned for 5G systems pose challenges for channel modeling. At these frequencies, surface roughness impacts wave propagation, causing scatter in non-specular directions that can have a large effect on received signal strength and polarization. To accurately predict channel characteristics for millimeter wave frequencies, propagation modeling must account for diffuse scattering effects. Wireless InSite’s diffuse scattering capability is based on Degli-Esposti’s work.
