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A test setup is deployed to study the influence of base station antenna height on the cellular network coverage. Both the numerical and experimental investigations are undertaken to evaluate the received electric field levels for different heights of the transmitting (TX) antenna and several distances between the transmitter and the receiver. The numerical simulation results demonstrate that when the TX antenna is mounted high above the ground, more fluctuations are induced in the electric field levels, resulting in possible dead zones for mobile communications. The measured received levels and data rates confirm the numerical simulation results. [ABSTRACT FROM AUTHOR]

Wireless communications are expected to take place in increasingly complicated scenarios, such as dense urban, forest, tunnel, and other cluttered environments. A key emerging challenge is to understand the physics and characteristics of wave propagation in these environments, which is critical for the analysis, design, and application of advanced mobile and wireless communication systems. In this paper, we present a full-wave field-based computational methodology for radio wave propagation in complex urban environments. Both transmitting/receiving antennas and propagation environments are modeled by first-principles calculations. A system-level, large scene analysis is enabled by the scalable, ultraparallel algorithms on the emerging high-performance computing platforms. The proposed computational framework is verified and validated with semianalytical models and representative measurements. [ABSTRACT FROM AUTHOR]

The next generation of intelligent vehicle systems will use wireless communication to connect a car and its passengers. It is therefore important to understand the in-cabin propagation characteristics of an automobile. This paper investigates the wireless channel native to these cabin enclosures. We present detailed, polarization dependent field measurements over a plane of interest in the cabin, and show that a simple analytical model gives reasonable agreement with our measurements. [ABSTRACT FROM PUBLISHER]

This paper presents the results of the first propagation measurement campaign conducted in the 2.4 GHz industrial, scientific and medical (ISM) band for low antenna heights in a North American boreal forest. The $2 \times 1$ multiple-input, single output measurements capture propagation conditions for wireless peer-to-peer or sensor networks in the boreal environment. Unlike many other forests, it is shown that ground reflections strongly influence large scale propagation for the low antenna boreal case. Results also indicate that scattering is severe but that both frequency diversity and multiple antenna techniques will be effective for mitigating and/or exploiting the fading caused by this scattering. [ABSTRACT FROM AUTHOR]

The objective of this presentation is to illustrate the accuracy of the Schelkunoff formulation over the Sommerfeld solution for a vertical electric dipole radiating over an imperfect ground. In an earlier paper, the alternate form of the Sommerfeld Green's function developed by Schelkunoff was presented (Schelkunoff, 1943 and Dyab, 2013). Here we demonstrate the application of this new methodology for two classes of problems. First, the problem of predicting the propagation path loss in a wireless communication environment is illustrated. The second application problem described in this paper deals with the verification of experimental data related to propagation over an Aluminum sheet at THz frequencies. It is seen that the main contribution of the reflected field is due to a specular image point as expected for a metal and the presence of surface waves in the total reflected field is absent, even though the permittivity of the metal is negative at these frequencies. Both theoretical predictions and experimental data demonstrate that there is little contribution to the reflected field due to a surface wave. Also, a clear definition is made to characterize surface waves as there is confusion as to what a surface wave really is. [ABSTRACT FROM PUBLISHER]