volume | PIER Journals

Abstract

A low-complexity first-order model was developed and verified to account for a single reflected propagation path in the complex transmission-coefficient matrix used for electromagnetic-field focusing by an antenna array. Electrodynamic and mathematical modeling was performed for a system comprising a transmitter, a receiving point, and an ideal specular reflector represented as a scattering point. The reflected-path contribution was incorporated directly into the transmission coefficients used to calculate the complex excitations of antenna-array radiators. The approach was evaluated using a three-element antenna array by comparing field focusing without a reflector, with an uncompensated reflector, and with reflector-aware excitation parameters. Changes in reflector position altered phase difference between direct and reflected waves, resulting in constructive or destructive interference at the receiving point. Taking the reflected path into account modified the calculated amplitudes and initial phases of the array excitations and partially compensated for reflector-induced field distortion. In the considered case, the normalized field amplitude after compensation differed by approximately 3% from the no-reflector case and increased by about 49% relative to the uncompensated case. The mathematical and electrodynamic results were in qualitative agreement. These findings demonstrate that including a reflected path in a transmission-coefficient matrix can improve near-field focusing accuracy in the presence of a reflector.

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Dr. Denis Iuzvik

Professor Maksim Stepanov