Abstract: Small, low cost, notch antennas are provided that can be internally incorporated into the existing structure of wireless communicators, and that are functional in a variety of orientations of the wireless communicator. The notch antenna is preferably formed in the ground plane conductor of a printed circuit board (PCB) that has RF circuitry thereon for receiving and transmitting RF signals. The notch preferably has a configuration that results in electromagnetic waves having a substantially omnidirectional radiation pattern being radiated from the notch when RF signals are applied to the notch. Integrating the antenna function into the same printed circuit board (PCB) on which the transmitter and/or receiver functions are also located eliminates the need for an additional antenna component. However, if necessary, a notch antenna surface component is also provided.

Abstract: In an antenna structure including multiple antennas, a first antenna can include a conductive patch and a second antenna can be adjacent the conductive patch. More particularly, the second antenna can define a central axis wherein the central axis is orthogonal with respect to the first antenna and wherein the central axis intersects a central portion of the conductive patch. Alternately or in addition, a first antenna can include a conductive patch with an opening through the conductive patch, and a second antenna can be adjacent the conductive patch wherein a feedline for the second antenna extends through the opening through the conductive patch.

Abstract: Inverted-F antennas that resonate within first and second frequency bands for use within communications devices, such as radiotelephones, are provided. A first planar conductive element has an elongated, rectangular configuration that extends along a first direction. The first planar conductive element has opposite first and second sides and an elongated edge. One or more additional planar conductive elements are electrically connected to the elongated edge of the first planar conductive element. Each additional planar conductive element has an elongated, rectangular configuration that extends along a second direction that is substantially parallel with the first direction. Each additional planar conductive element is maintained in adjacent, co-planar, spaced-apart relationship with the first planar conductive element.

Abstract: Antenna systems for transmitting electrical signals are provided which include a quadrifilar helix antenna. A first antenna feed is coupled to the quadrifilar helix antenna for exciting the radiating elements in phase quadrature. A second antenna feed is also coupled to the quadrifilar helix antenna for exciting the radiating elements in-phase. These antenna systems may be operated in either a helical radiation mode, where the antenna may be designed to radiate as a resonant quadrifilar helix antenna, or in a monopole radiation mode, where the antenna acts as the equivalent of a large monopole antenna. Additionally, the antenna systems may further include means for matching the impedance of the quadrifilar helix antenna to the impedance of either or both of the antenna feeds.