Deterministic field prediction has been widely used to provide channel data for coverage analysis. Among these prediction tools, point cloud-based methods have been developed for millimeter-wave frequencies in order to characterize the environment with higher precision, but they have not taken into account all the necessary propagation mechanisms. In this paper, we present the implementation for predicting both specular reflections and diffraction as well as the total channel, including the aforementioned mechanisms along with scattering and shadowing. Both line-of-sight (LOS) and non-LOS channels are predicted and validated against measurements in a cafeteria. The result shows excellent agreement between prediction and measurement in terms of power delay profiles, power angular spectra, path loss, mean delay, delay spread, and azimuth spread.

Fused filament fabrication (FFF) is a well-known and greatly accessible additive manufacturing technology, that has found great use in the prototyping and manufacture of radiofrequency componentry, by using a range of composite thermoplastic materials that possess superior properties, when compared to standard materials for 3D printing. However, due to their nature and synthesis, they are often a great challenge to print successfully which in turn affects their microwave properties. Hence, determining the optimum printing strategy and settings is important to advance this area. The manufacturing study presented in this paper shows the impact of the main process parameters: printing speed, hatch spacing, layer height and material infill, during 3D printing on the relative permittivity (ε_r), and loss tangent (tanδ) of the resultant additively manufactured test samples. A combination of process parameters arising from this study, allowed successful 3D printing of test samples, that marked a relative permittivity of 9.06 ± 0.09 and dielectric loss of 0.032 ± 0.003.

The multiplicity of targets of the 5G and further future technologies, set by the modern societies and industry, lacks the establishment of design methods for the highly multidisciplinary application of wireless platforms for small cells. Constraints are set by the overall energy concept, structural safety and sustainability. Various Smart poles and Light poles exist but it is challenging to define the design drivers especially for a composite load-carrying structure. In this study, the design drivers of a composite 5G smart pole are determined and the connecting design between finite element modelling (FEM), signal penetration and computational fluid dynamics (CFD) for thermal analysis are reported as an interdisciplinary process. The results emphasize the significant effects of thermal loading on the material selection. The physical architecture, including various cutouts, is manipulated by the needs of the mmW radios, structural safety and the societal preferences of sustainable city planning, i.e., heat management and aesthetic reasons. Finally, the paint thickness and paint type must be optimized due to radome-integrated radios. In the future, sustainability regulations and realized business models will define the cost-structure and the response by customers.

Microwave radars represent a viable solution to perform rapid and nondestructive snowpack analyses. Depending on the working frequency, they are required to provide a suitable compromise between the penetration depth and the spatial resolution. For these reasons, antennas able to cover relatively large fractional bandwidths at a few gigahertz are fundamental, while minimizing the antenna mass and volume to do not jeopardize the portability often required to these systems. This letter presents the development and the experimental results of a novel antenna realized by three-dimensional printing, based on a double-ridge waveguide configuration and on the use of different infill percentages. The operation bandwidth is from 2.3 to 6 GHz, with a gain at the central frequency of around 5 dBi. The antenna is fabricated using low-loss filaments, with a relatively high dielectric constant (4.5); thus, maintaining the mass in the order of 100 g, with an encumbrance of 5.16 × 2.40 × 6.78 cm ³ .

In this paper, we compare the radio propagation channels characteristics between 28 and 140 GHz bands based on the wideband (several GHz) and directional channel sounding in a shopping mall environment. The measurements and data processing are conducted in such a way to meet requirements for a fair comparison of large- and small- scale channel parameters between the two bands. Our results reveal that there is high spatial-temporal correlation between 28 and 140 GHz channels, similar numbers of strong multipath components, and only small variations in the large-scale parameters between the two bands. Furthermore, when including the weak paths there are higher total numbers of clusters and paths in 28 GHz as compared to those in 140 GHz bands. With these similarities, it would be very interesting to investigate the potentials of using 140 GHz band in the future mobile radio communications.

In this paper, we parameterize an excess loss-based multipath component (MPC) cross-polarization ratio (XPR) model in indoor and outdoor environments for above-6 GHz frequency bands. The results are based on 28 measurement campaigns in several frequency bands ranging from 15 to 80 GHz. A conventional XPR model of an MPC assuming a constant mean value fits our measurements very poorly and moreover overestimates the depolarization effect. Our measurements revealed a clear trend that the MPC XPR is inversely proportional to an excess loss in reference to the free-space path loss. The model is physically sound as a higher excess loss is attributed to more lossy interactions or to a greater number of interactions with objects, leading to a greater chance of depolarization. The measurements furthermore showed that the MPC XPR is not strongly frequency or environment dependent. In our MPC XPR model, an MPC with zero-dB excess loss has a mean XPR of 28 dB. The mean XPR decreases half-a-dB as the excess loss increases by every dB and the standard deviation around the mean is 6 dB. The model is applicable to existing channel models to reproduce realistic MPC XPRs for the above 6-GHz radio links.