Abstract: An antenna includes a first loop defining a first enclosed area and having a first phase center point, a second loop coupled to the first loop and disposed substantially parallel to the first loop, the second loop defining a second enclosed area, and a third loop coupled to the first loop and the second loop and substantially parallel to the first loop, the third loop defining a third enclosed area with a plurality of adjuster elements coupled to at least one of the first loop, the second loop, or the third loop to provide an adjustable loop and configured to expand or contract the enclosed area of the adjustable loop.

Abstract: An adjustable antenna enables far-field radiation from the antenna to be reduced, minimized, and/or substantially eliminated while near-field radiation from the antenna may be substantially maintained. In some embodiments, an antenna includes a first loop defining a first enclosed area and having a first phase center point defined by the geometric center point of the first enclosed area, a second loop coupled to the first loop and disposed substantially parallel to the first loop, the second loop defining a second enclosed area and a second phase center point defined by the geometric center point of the second enclosed area, and a third loop coupled to the first loop and the second loop and substantially parallel to the first loop, the third loop defining a third enclosed area and a third phase center point defined by the geometric center point of the third enclosed area.