A broadband dual polarized antenna includes pairs of electrically separated stacked spiral antenna arms. Each pair of spiral arms have opposite senses and are orthogonal to each other. The relative overlap of each pair of spirals is kept to a minimum so that radiation received and transmitted by the bottom pair of spiral arms will be degraded as little as possible. No overlap exists within each pair of spiral arms, and the pair need not be co-planar, but do share a common axis with the other pair of spiral arms. The spiral arms can be segmented or may comprise a number of spiralling wire elements. A plurality of such antenna structures can be formed into an array capable of beam shaping or scanning.

Dual polarized spiral antenna

An antenna/receiver device including a slow-wave antenna for receiving RF signals. The antenna has a pair of terminals for providing odd-mode antenna excitation of the antenna. A differential-input circuit is connected to the antenna terminals for providing odd-mode, anti-phase current excitation of the terminals and for amplifying the RF signals. A processing circuit is provided for operating on the RF signals and generating an output signal from the RF signals. An optical transducer optically couples the output signal out of the antenna/receiver device. In one embodiment of the invention, the processing circuit comprises a mixing circuit means for mixing the RF signals with a local oscillator signal for generating an intermediate frequency output signal. In an alternate embodiment of the invention, the processing circuit comprises a detector for detecting video information contained in the RF signals.

Millimeter wave fiber-optically linked antenna receiver device

An antenna includes a support structure and radiating element. The radiating element includes a dielectric planar substrate having a first and a second surface, at least two conductive spiral arms extending outward from and spiraling about an axis of rotation formed on the first surface, and a feed conductor extending outward from and spiraling about an axis of rotation formed on the second surface. The feed conductor may be substantially aligned with one of the conductive spiral arms. When the support structure is placed upon a substantially planar surface, the radiating element is positioned at height h from the planar surface, wherein height h is about one-fourth the wavelength of the antenna's operating frequency. The antenna may produce an omni-directional antenna pattern in azimuth and a broad antenna pattern in elevation, with both patterns having nulls near the horizon. An external reflector may be operatively coupled to the antenna.

Passive wide-band low-elevation nulling antenna

A device includes a first substrate that has a first antenna having a first loop and second loop that form loop shapes viewed in a planar projection; and a second substrate that has a second antenna having a third loop and fourth loop that form loop shapes viewed in the planar projection. The first substrate and the second substrate are disposed so that the first antenna and the second antenna face each other. At least when the first substrate and the second substrate operate, the first antenna and the second antenna are in a state that the first antenna and the second antenna are capable of being magnetically coupled.

Communication device and semiconductor chip

A two-antenna array includes first and second coaxial antenna members spaced such that the fore member is in the distant (far) front lobe field of the aft element. Each antenna member includes a like-oriented circularly polarized antenna element with microwave absorbing material disposed in a cavity about its aft, back lobe direction. A high degree of electrical isolation exists between antennas by reason of the aggregate inter-element transmission losses resulting from (i) space propagation loss, (ii) antenna front-to-back discrimination, and (iii) polarization isolation.

Coaxial antenna configuration with high inter-element isolation

Video pulse radio frequency receivers are rendered sensitive to continuous waves by means of an amplitude modulation technique involving coupling between circularly polarized antennas. The circularly polarized antennas incorporate semiconductor diodes as an integral part of the antenna structure. Two circularly polarized antennas with diodes incorporated therein are mounted in tandem with counter rotating faces directed toward a source of linearly polarized electromagnetic wave. One circularly polarized component of the electromagnetic wave excites the first antenna, while the counter rotating component passes through the first antenna and excites the second antenna. The integral diode of the antennas acts respectively as a detector and modulator, with radio frequency coupling being provided by the tandem arrangement which locates the antenna faces of like polarization sense adjacent each other. By arranging a multiple of the pairs of tandem mounted antennas in a distributed pattern, direction finding capabilities are provided.

D Gershberg

Papers

Electromagnetic wave receiver