A Colocated Magnetic Loop, Electric Dipole Array Antenna (Preliminary Results)

Abstract

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Electric lines of force of an electrically small dipole-loop antenna array

“…In this plane, the contours are asymmetric when the real part of is nonzero, resulting in lines of force that add constructively in the positive direction and mostly cancel in the direction. This is the plane in which previously an increased directivity effect was predicted for the dipole-loop array provided is purely real, implying that the currents on the dipole and loop must be in phase quadrature [14]. In Fig.…”

“…This corresponds to the case where and from (5) when . Also previously, we had determined that when the loop and dipole currents were driven in phase, then the array radiates exactly as if each element stood alone [14]. This is the case where is pure imaginary.…”

“…Previously, we had determined via both analysis and MM modeling that when the loop current is driven in phase quadrature to the dipole current, an increased directivity effect is seen [14]. This corresponds to the case where and from (5) when .…”

“…The simplest example of this class of antennas-an electric-dipole magnetic-loop array-is the subject of the present work. A complete analysis (including moment method (MM) modeling) has been published elsewhere [14], [15]. An independent verification of the numerical results in [14] has been performed also [16].…”

“…A complete analysis (including moment method (MM) modeling) has been published elsewhere [14], [15]. An independent verification of the numerical results in [14] has been performed also [16]. A prototype array with matching networks has been built and is currently being tested [17], [18].…”