Abstract: One or more feedback elements generate a feedback signal in response to a transmitted signal outputted by each radiator of the antenna system. This feedback signal is received by each radiator, also described as a radiating element, and combined with any leakage signal present at the port of the antenna. Because the feedback signal and the leakage signal are set to the same frequency and are approximately 180 degrees out of phase, this signal summing operation serves to cancel both signals at the output port, thereby improving the port-to-port isolation characteristic of the antenna. Each feedback element can include a photo-etched planar metal strip supported by a planar dielectric card made from printed circuit board material. Such feedback elements can provide a high degree of repeatability and reliability in that the manufacturing of such feedback elements can be precisely controlled.

Abstract: One or more feedback elements generate a feedback signal in response to a transmitted signal outputted by each radiator of the antenna system. This feedback signal is received by each radiator, also described as a radiating element, and combined with any leakage signal present at the port of the antenna. Because the feedback signal and the leakage signal are set to the same frequency and are approximately 180 degrees out of phase, this signal summing operation serves to cancel both signals at the output port, thereby improving the port-to-port isolation characteristic of the antenna. Each feedback element can include a photo-etched planar metal strip supported by a planar dielectric card made from printed circuit board material. Such feedback elements can provide a high degree of repeatability and reliability in that the manufacturing of such feedback elements can be precisely controlled.

Abstract: One or more feedback elements generate a feedback signal in response to a transmitted signal outputted by each radiator of the antenna system. This feedback signal is received by each radiator, also described as a radiating element, and combined with any leakage signal present at the port of the antenna. Because the feedback signal and the leakage signal are set to the same frequency and are approximately 180 degrees out of phase, this signal summing operation serves to cancel both signals at the output port, thereby improving the port-to-port isolation characteristic of the antenna. Each feedback element can include a photo-etched planar metal strip supported by a planar dielectric card made from printed circuit board material. Such feedback elements can provide a high degree of repeatability and reliability in that the manufacturing of such feedback elements can be precisely controlled.

Abstract: One or more feedback elements generate a feedback signal in response to a transmitted signal outputted by each radiator of the antenna system. This feedback signal is received by each radiator, also described as a radiating element, and combined with any leakage signal present at the port of the antenna. Because the feedback signal and the leakage signal are set to the same frequency and are approximately 180 degrees out of phase, this signal summing operation serves to cancel both signals at the output port, thereby improving the port-to-port isolation characteristic of the antenna. Each feedback element can include a photo-etched planar metal strip supported by a planar dielectric card made from printed circuit board material. Such feedback elements can provide a high degree of repeatability and reliability in that the manufacturing of such feedback elements can be precisely controlled.

Abstract: An improved antenna system for transmitting and receiving electromagnetic signals comprising a backplane having a length and a vertical axis along the length. A plurality of dipole radiating elements project outwardly from a surface of the backplane. Each of the elements includes a balanced orthogonal pair of dipoles aligned at first and second predetermined angles with respect to the vertical axis, forming crossed dipole pairs. An unbalanced feed network extends along the backplane and connected to the radiating elements. A printed circuit board balun is attached to each of the dipoles. The antenna can also include a parasitic element positioned along the vertical axis such that primary electromagnetic fields induce currents on the parasitic element, these induced currents re-radiate secondary electromagnetic fields which cancel portions of the primary electromagnetic fields, thereby improving isolation.