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This paper presents a powerful method to analyze antennas which can be considered principally two-dimensional (2-D) or cylindrical, except for some three-dimensional (3-D) physical or equivalent sources, e.g., dipoles or slots. It is shown by Fourier transform techniques that such antennas can be analyzed as 2-D problems with harmonic longitudinal field variation. The radiation pattern can often be determined directly from a finite set of such 2-D solutions, each one obtained by any method, e.g., the moment method. The mutual interaction between the cylindrical scatterer and the sources must be calculated to determine the exact current distribution on the sources and their impedances or admittances. This is facilitated by performing an inverse Fourier transform of an infinite spectrum of the numerical 2-D solutions followed by a moment method solution in the spatial domain to satisfy the boundary conditions on the 3-ID equivalent sources themselves. The inverse Fourier transform is simplified by the use of asymptote extraction. The method is in itself a hybrid technique as one method is used to solve the harmonic 2-D problem, and the other to solve for the source currents.

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Body-to-body wireless networks (BBWNs) have great potential to find applications in team sports activities among others. However, successful design of such systems requires great understanding of the communication channel as the movement of the body components causes time-varying shadowing and fading effects. In this study, we present results of the measurement campaign of BBWN during running and cycling activities. Among others, the results indicated the presence of good and bad states with each state following a specific distribution for the considered propagation scenarios. This motivated the development of two-state semi-Markov model, for simulation of the communication channels. The simulation model was validated using the available measurement data in terms of first and second order statistics and have shown good agreement. The first order statistics obtained from the simulation model as well as the measured results were then used to analyze the performance of the BBWNs channels under running and cycling activities in terms of capacity and outage probability. Cycling channels showed better performance than running, having higher channel capacity and lower outage probability, regardless of the speed of the subjects involved in the measurement campaign.