Abstract-In this paper a non-line-of-sight (NLOS) path-loss and fading model developed for vehicle-to-vehicle (V2V) communication at 5.9 GHz is validated with independent and realistic measurement data. The reference NLOS model is claimed to be flexible and of low complexity, and incorporates specific geometric aspects in a closed-form expression. We validated the accuracy of the model with the help of realistic channel measurements performed in selected street intersections in the city of Lund and Malmö, Sweden. The model fits well, with a few exceptions, to the measurements. Those are in turn made in different intersections having variable geometries and scattering environments. It is found that the model can be made more general if an intersection dependent parameter, that depends on the property and number of available scatterers in that particular intersection, is included in the model.

Inside a tunnel, electromagnetic wave propagation differs strongly from the well understood "open-air" situation. The characterization of the tunnel environment is crucial for deploying vehicular communication systems. In this paper we evaluate vehicle-to-vehicle (V2V) radio channel measurements inside a tunnel. We estimate the time-varying root mean square (rms) delay and Doppler spreads, as well as the excess delay and the maximum Doppler dispersion. The fading process in V2V communications is inherently non-stationary. Hence, we characterize the stationarity time, for which we can consider the fading process to be wide sense stationary.We show that the spreads, excess delay, and maximum Doppler dispersion are larger on average when both vehicles are inside the tunnel compared to the "open-air" situation. The temporal evolution of the stationarity time is highly influenced by the strength of time-varying multipath components and the distance between vehicles. Furthermore, we show the good fit of the rms delay and Doppler spreads to a lognormal distribution, as well as for the stationarity time. From our analysis we can conclude that the IEEE 802.11p standard will be robust towards inter-symbol and inter-carrier interference inside a tunnel.

The effects of external pressure on a high-performing dysprosocenium single-molecule magnet are investigated using a combination of X-ray diffraction, magnetometry and theoretical calculations. The effective energy barrier (Ueff) decreases from...

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Single-molecule magnet materials owe their function to the presence of significant magnetic anisotropy, which arises from the interplay between the ligand field and spin–orbit coupling, and this is responsible for setting up an energy barrier for magnetic relaxation. Therefore, chemical control of magnetic anisotropy is a central challenge in the quest to synthesize new molecular nanomagnets with improved properties. There have been several reports of design principles targeting such control; however, these principles rely on idealized geometries, which are rarely obtained in crystal structures. Here, we present the results of high-pressure single-crystal diffraction on the single-ion magnet, Co­(SPh)4(PPh4)2, in the pressure range of 0–9.2 GPa. Upon pressurization a sequence of small geometrical distortions of the central CoS4 moeity are observed, enabling a thorough analysis of the magneto-structural correlations. The magneto-structural correlations are investigated by theoretical analyses of the pressure-dependent experimental molecular structures. We observed a significant increase in the magnitude of the zero-field splitting parameter D, from −54.6 cm–1 to −89.7 cm–1, which was clearly explained from the reduction of the energy difference between the essential d xy and d x 2–y 2 orbitals, and structurally assigned to the change of an angle of compression of the CoS4 moeity.