Telecommunications Research Laboratories

Uti Limited Partnership

Other

Northern Telecom Limited

Ronald H Johnston

Elise Fear

Edwin Tung

Dean Kitchener

Tin Chau Choi

Laurent Joseph Levesque

A dual circularly polarized antenna is described. In some embodiments, the antenna includes a waveguide having an aperture at a first end and a conducting component at a second end, the conducting component shorting the waveguide. A first driven dipole is substantially orthogonal to a second driven dipole, and both the first and second driven dipoles are located near the aperture of the waveguide. The first and second driven dipoles are connected to the conducting component by one or more plates and configured to be fed in quadrature. A resonator is positioned near the first and second driven dipoles.

Dual circularly polarized antenna

An antenna includes a waveguide having an aperture at a first end and a conducting component at a second end, the conducting component shorting the waveguide and a first set of two orthogonal dipoles, fed in quadrature, the orthogonal dipoles located near the aperture of the waveguide operating close to its dominant mode cut off frequency.

A broadband compact antenna comprises an electric dipole or monopole coupled or connected in parallel to a slot antenna. The slot antenna is composed of a flat, square or rectangular conducting sheet with a slot having a variety of possible shapes including a bow-tie or rectangle. The slot is then fed at the center by a coaxial transmission line with its outer conductor bonded to the sheet. To obtain broadband characteristics and compactness, a dipole or monopole, formed using either wire, flat strips or shapes formed in sheets of metal, is located in close proximity to the center of the slot.

Broadband compact slot dipole/monopole and electric dipole/monopole combined antenna

A multiport beamforming antenna provides multidirectional beam patterns with minimum interference comprising multiple, as for example twelve, radiating elements mounted on a conducting ground plane. Multiple, for example six, reflecting surfaces, each having a shape of one quarter of a circle or an ellipse, are radially disposed about the center of a round ground plane conductor to give a hemispherical shape with multiple, for example six, equal sectors. Each sector of the multiport antenna contains two types of radiating elements mounted adjacent to the corner of the reflector. The first elemental antenna is responsive to energy having a first polarization, while the second elemental antenna is responsive to energy having a polarization orthogonal to the first polarization. With such an arrangement, all the radiating elements are located in close proximity without coupling signals to each other, and each element is capable of producing a directional radiation pattern in an independent manner. Consequently, the physical area required to install the antenna is minimized, and the antenna provides very good hemispherical coverage and for example may be placed anywhere on the ceiling of a room to provide coverage of the entire room.

Multiport antenna

The present invention relates to antennas and in particular relates to a multi-resonant antenna. The present invention addresses the requirement for dual frequency antennas operable in two distinct frequency bands. In accordance with a first aspect of the invention, there is provided a multi-resonant antenna comprising first and second conductive elements which antenna elements extend relative to a ground plane; wherein the elements of the antenna structure are adapted to couple between themselves to provide a variable phase velocity for surface currents of the radio signals. A method of operation is also disclosed.

Multi-resonant antenna

A compact diversity antenna is presented consisting of two electrically isolated orthogonal loop conductors joined at a midpoint. This midpoint is also electrically attached to a vertical conductor which produces a third mode of operation electrically isolated from the first modes. The two horizontal conductors and the vertical conductor may be constructed to have various relationships with a ground plane of various shapes and sizes. Some of the possible feed arrangements for each of the antennas is presented as well as matching and tuning circuits. All three antenna elements are found to have relatively weak near electric and magnetic fields on the ground plane side of the antenna where the ground plane is small in extent. This feature provides for reduced radiation into the head and neck of the cellular phone user.

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Calgary, Canada

Ronald H Johnston