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The D-band among all sub-THz and THz radio frequencies is foreseen as the first one to be utilized for communications. Such high frequency communication links are particularly susceptible to shadowing events, e.g., caused by the human body. In this paper we present results of a D-band channel measurement campaign, which was conducted to characterize the impact of human blockage, with a focus on the excess attenuation and temporal evolution of human body shadowing. The attenuation caused by single-person blockers with different physical characteristics was measured with human frontal and lateral crossing the line-of-sight link. Predicting results of two knife-edge diffraction models are compared with the measurement curves, which both underestimate the attenuation levels especially for the volunteer with larger size. Meanwhile, we quantify the deep fading duration varying with the fading depth, which helps to optimize the beam alignment strategy in order to maintain the sufficient signal-to-noise ratio when the dominant path is heavily obstructed.

A need for measurement data for frequencies above 100 GHz has increased. In this paper, we present the measurement system for millimeter wave frequencies (30–300 GHz). It is based on Keysight PNA-X vector network analyser with frequency extenders mounted on custom built 3-axis rotation stages (both the transmitter and receiver sides). We present some initial results from measurements conducted in an office corridor. Both line-of-sight (LOS) and non-LOS (NLOS) cases are included in the measurement set-ups. The results show that in all cases the channels are sparse with clear clusters from large reflecting surfaces, such as walls and floors. The measured power levels are rather strong indicating relatively low reflection losses. While the channels were sparse, there were still typically relatively large numbers of distinguishable paths. The numbers of observable paths as well as the delay spread of the channel increase with increasing beamwidth.

Providing reliable low latency wireless links for advanced manufacturing and processing systems is a vision of Industry 4.0. Developing, testing and rating requires accurate models of the radio propagation channel. The current 3rd generation partnership project (3GPP) new radio (NR) model as well as the quasi deterministic radio channel generator (QuaDRiGa) lack the propagation parameters for the industrial indoor scenario. To close this gap, measurements were conducted at 2.37 GHz and 5.4 GHz at operational Siemens premises in Nuremberg, Germany. Furthermore, the campaign was planned to allow the test and parameterization of new features of the QuaDRiGa channel model such as support for device-to-device (D2D) radio links and spatial consistency. A total of 5.9 km measurement track was used to extract the statistical model parameters for line of sight (LOS) and Non-LOS propagation conditions. It was found that the metallic walls and objects in the halls create a rich scattering environment, where a large number of multipath components arrive at the receiver from all directions. This leads to a robust communication link, provided that the transceivers can handle the interference. The extracted parameters can be used in geometric-stochastic channel models such as QuaDRiGa to support simulation studies, both on link and system level.

We derive a full measurement-based parametrization for a 3-D geometry-based stochastic channel model for an urban microcell type of environment at 10 GHz. The measurements were performed with a vector network analyzer and dual polarized virtual arrays at the bandwidth of 500 MHz. The proposed parametrization is validated by channel simulations. Multiple-input multiple-output channel is reconstructed from the measured data and compared with channel generated by the quasi deterministic radio channel generator using the proposed statistical parameters. The capacity and eigenvalue distribution are used as the validation metrics, showing almost perfect match between the reconstructed and simulated channels.

This letter presents analysis of diffraction over multiple shadowing screens at frequency range of 10–18 GHz. Up to ten pieces of thin metal sheets with dimensions of 130 × 100 cm at variable spacing were used as diffraction screens. The aim of this study is to investigate the total shadowing effect of multiple knife-edge diffractions at frequencies above the legacy cellular systems. The results show the necessity to adjust the Walfisch-Bertoni path loss model for the higher frequencies in the future fifth-generation systems.