The mutual impedance of perpendicular half-wave antennas

"June 7, 1960.""Reprinted from Volume XV, Proceedings of the National Electronics Conference, Hotel Sherman, Chicago, Illinois, October 13, 14, 15, 1959."The mutual impedance of two coupled linear antennas is needed to obtain the radiation impedance of an array of linear antennas and to determine the effect of one antenna upon a neighboring antenna, for example, the effect of a transmitting antenna upon an adjacent receiving antenna. Much work has been done on two parallel half wave antennas, but little quantitative data are available on skew antennas. The work presented in this paper is concerned with the mutual impedance of two half wave antennas at right angles. The method employed in calculating the mutual impedance was that of Carter and the resulting integrals were evaluated by an approximation method using a digital computer. The results are presented as curves in rectangular form for both the resistive and reactive components for the complex values of the mutual impedance. The curves indicate that the maximum coupling for two antennas at right angles occurs when the two antennas form an approximate L-shape