HIGH FREQUENCY FFT ANALYSIS OF AN ELECTRICALLY LONG MONOPOLE ANTENNA

Abstract

In previous work the currents along a monopole, 20 meters long and operating at 299.8 MHz, placed over a perfectly conducting ground plane were analyzed using several modeling techniques and the Numerical Electromagnetics Code version two (NEC-2). An interesting topic to investigate is the presence of spurious modes of propagation along the monopole. Such modes of propagation are studied for each modeling technique, and conclusions are drawn accordingly. When the data are transformed into the k- space domain, using Fast Fourier Transforms (FFT), the spurious mode behavior along the monopole becomes clearly visible. This technique provides valuable information not yet documented. [Vol. 9, No. 2 (1994), pp 114-119]