A plurality of antenna elements on a dielectric substrate are adapted to launch or receive electromagnetic waves in or from a direction substantially away from either a convex or concave edge of the dielectric substrate, wherein at least two of the antenna elements operate in different directions. Slotlines of tapered-slot endfire antennas in a first conductive layer of a first side of the dielectric substrate are coupled to microstrip lines of a second conductive layer on the second side of the dielectric substrate. A bi-conical reflector, conformal cylindrical dielectric lens, or discrete lens array improves the H-plane radiation pattern. Dipole or Yagi-Uda antenna elements on the conductive layer of the dielectric substrate can be used in cooperation with associated reflective elements, either alone or in combination with a corner-reflector of conductive plates attached to the conductive layers proximate to the endfire antenna elements.

Multi-beam antenna

Aspects of the subject disclosure may include, for example, receiving, by a feed point of a dielectric antenna, electromagnetic waves from a dielectric core coupled to the feed point without an electrical return path, where at least a portion of the dielectric antenna comprises a conductive surface, directing, by the feed point, the electromagnetic waves to a proximal portion of the dielectric antenna, and radiating, via an aperture of the dielectric antenna, a wireless signal responsive to the electromagnetic waves being received at the aperture. Other embodiments are disclosed.

Method and apparatus for coupling an antenna to a device

A distributed antenna and backhaul system provide network connectivity for a small cell deployment. Rather than building new structures, and installing additional fiber and cable, embodiments described herein disclose using high-bandwidth, millimeter-wave communications and existing power line infrastructure. Above ground backhaul connections via power lines and line-of-sight millimeter-wave band signals as well as underground backhaul connections via buried electrical conduits can provide connectivity to the distributed base stations. An overhead millimeter-wave system can also be used to provide backhaul connectivity. Modules can be placed onto existing infrastructure, such as streetlights and utility poles, and the modules can contain base stations and antennas to transmit the millimeter-waves to and from other modules.

Backhaul link for distributed antenna system

A distributed antenna system is provided that frequency shifts the output of one or more microcells to a 60 GHz or higher frequency range for transmission to a set of distributed antennas. The cellular band outputs of these microcell base station devices are used to modulate a 60 GHz (or higher) carrier wave, yielding a group of subcarriers on the 60 GHz carrier wave. This group will then be transmitted in the air via analog microwave RF unit, after which it can be repeated or radiated to the surrounding area. The repeaters amplify the signal and resend it on the air again toward the next repeater. In places where a microcell is required, the 60 GHz signal is shifted in frequency back to its original frequency (e.g., the 1.9 GHz cellular band) and radiated locally to nearby mobile devices.

Remote distributed antenna system

Aspects of the subject disclosure may include, for example, a device that facilitates transmitting electromagnetic waves along a surface of a wire that facilitates delivery of electric energy to devices, and sensing a condition that is adverse to the electromagnetic waves propagating along the surface of the wire. Other embodiments are disclosed.

Method and apparatus for sensing a condition in a transmission medium of electromagnetic waves

An antenna system is described including a reflector antenna, responsive to radio frequency signals at a first frequency, having a first reflector surface, a second reflector surface and a Cassegrain feed. The antenna system further includes an array antenna having a plurality of antenna elements responsive to radio frequency signals having a second different frequency, wherein a center element is in a common location with the feed of the reflector antenna. With such an arrangement, an improved dual band antenna system is provided. By providing the center element of the array antenna in a common location with the feed of the reflector antenna, a dual band radio frequency antenna system is provided which is more compact with improved radiation characteristics than known similar configured antennas.

Dual polarized dual band antenna

A description is given of an antenna consisting of an interconnected wire grid formed by etching metallic lines on a dielectric sheet backed by a metallic ground plane. The theory of operation, analytical model, and experimental findings for this approach to a printed array are described. The device is low cost, light weight, and has sufficient bandwidth to be of use in a variety of applications. An analytical model is developed which establishes transmission line equivalent circuits for the wire grid elements. Current distributions determined from the model are shown to predict accurately the measured pattern performance of a typical implementation. The bandwidth as established by various pattern parameters is quantitatively assessed. Particular emphasis is given to methods of amplitude control through control of line impedances. A particular design implementation is presented for a five-wavelength circular array with independent quadrant control. Measured results from this configuration are compared to theory.

The wire grid microstrip antenna

In a guided missile, a microstrip antenna, including a patch radiator with parasitic elements, flush-mounted and conforming to the side of the missile, producing an antenna beam which is tilted in required direction for use as a link or fuse antenna is shown Parasitic elements are used to direct the beam away from the antenna normal to the desired direction

Microstrip antenna with parasitic elements

A radar antenna is shown in a first embodiment to have a ground plane and a feed line on opposite sides of a dielectric sheet and a ring-shaped antenna element on another dielectric sheet to form a microstrip assembly wherein such antenna element is capacitively coupled to the feed line. In a second embodiment the radar antenna has a parasitic antenna element on still another dielectric sheet, such parasitic antenna element being in register with the ring-shaped antenna element.

Microstrip antenna with circular ring

A compact RF monopulse receiver circuit having a relatively low noise figure which is particularly useful for operation in the millimeter wave frequency range is described. The compact monopulse receiver finds use in small projectile and small missile applications. Also, a combination of transmit signal protection circuitry and receiver circuit architecture allows the RF monopulse receiver circuit to operate in a missile or other projectile which utilizes high RF power transmit signals. The RF monopulse receiver circuit can directly provide a radiation pattern for target detection and tracking or alternatively, the RF monopulse receiver circuit can function as a monopulse feed circuit which can be used, for example, in a quasi-optically fed reflector antenna.

John F. Toth

Papers

Dual polarized dual band antenna

The wire grid microstrip antenna

Microstrip antenna with parasitic elements

Microstrip antenna with circular ring

Radio frequency receiving circuit