Path Loss Models

60-GHz wireless communication system will become the world’s first massively wireless broadband millimetre wave propagation system. The data rates and bandwidth provided by this band are excellent. If we add all bandwidths currently used by all wireless communication systems then it will represents only a small percentage of total bandwidth available on this 60 GHz band. Therefore it can be a good solution for future 5G technology for mobile communication. But this band will face some design challenges which makes this band difficult to implement in consumer market. In this paper, we have presented literature review of papers which have shown different design challenges faced by 60 GHz band. Some major design challenges of 60 GHz band are high path loss, rapid variations in the channel, high power requirements, and shadowing. Some path loss models are also given here for calculating path loss for both LOS and NLOS cases.

Path loss models necessitate effective deployment of underwater sensor networks by predicting amount of loss in signal strength of the propagating wave. There are several existing path loss models that have been developed for terrestrial purpose. However, due to significant challenges unique to underwater network, these existing terrestrial models cannot be directly applied to aquatic applications. Therefore, path loss model is required to be distinctly designed for underwater applications. Three modes of underwater communication include acoustics, optics and radio waves. We have proposed a novel path loss model based on variable conductivity. Our research highlights different ways in which depth and temperature of seawater impact on signal propagating undersea. Experimental results reveal that attenuation loss confronted by deep sea is comparatively lesser than that in case of shallow water. Furthermore, communication model for deep water is also developed that combines acoustic and radio waves for communication in acoustic sensor network.

Unmanned aerial vehicles (UAVs) can be used as aerial wireless base stations when cellular networks go down. Prior studies on UAV-based wireless coverage typically consider outdoor scenarios, where a UAV and wireless devices are outdoor. In this paper, the problem of UAV placement is studied, where the goal is to find the optimum location of a single UAV that prolongs the lifetime of indoor wireless devices. First, a realistic Indoor-Outdoor path loss model is presented and the tradeoff introduced by this model is described. Then, the problem of UAV placement is formulated, where the goal is to find the optimum UAV location that prolongs the lifetime of indoor wireless devices. It can be proven that the constraint sets of the problem can be represented by a convex set in terms of three variables. To this end, an algorithm to find the optimum UAV location is proposed. Simulation results are presented to validate the effectiveness of the proposed algorithm.

Path loss models necessitate effective deployment of underwater sensor networks by predicting amount of loss in signal strength of the propagating wave. There are several existing path loss models that have been developed for terrestrial purpose. However, due to significant challenges unique to underwater network, these existing terrestrial models cannot be directly applied to aquatic applications. Therefore, path loss model is required to be distinctly designed for underwater applications. Three modes of underwater communication include acoustics, optics and radio waves. We have proposed a novel path loss model based on variable conductivity. Our research highlights different ways in which depth and temperature of seawater impact on signal propagating undersea. Experimental results reveal that attenuation loss confronted by deep sea is comparatively lesser than that in case of shallow water. Furthermore, communication model for deep water is also developed that combines acoustic and radio waves for communication in acoustic sensor network.