The Effect of Windowing Function on the Accuracy Improvement of the High Directivity Millimeter Wave Antenna Characterization

Abstract

High-gain antennas can be used to compensate for attenuation in millimeter-wave communication technology. So, the antenna's characterization is vital for both the measurement results' accuracy and the measurement setup. High-gain reflector antennas can be characterized using the near-field method, where the antenna's radiation measurement is conducted in the near-field region and then transformed into far-field values using Fourier transformation with the Fast Fourier Transform algorithm. To achieve better accuracy, this technique requires the application of several methods. This paper discusses how the selection of window functions, which are applied before the Fourier transform, influences the production of antenna characteristics with high accuracy by reducing spectral leakage from the data. Ten window functions commonly used in data processing will be tested for their accuracy in antenna parameters such as 3-dB and 10-dB bandwidth, as well as antenna null parameters around the main lobe. Two window functions that can be used in applications related to this research are the Gaussian window and the Tukey window, providing more detailed antenna characteristics.