California Microwave, Inc.

International Telephone and Telegraph Corporation

Richard C Dempsey

Carl O Jelinek

Daniel W Drago, Jr

Antenna elements and systems and other radio and microwave frequency devices are constructed with a high index of refraction medium having high matched values of relative permeability and relative permittivity, and a low loss tangent. By making the permeability of the transmission medium substantially equal to its relative permittivity, the impedance of the material is matched to that of the surrounding free space or air. By immersing a radiating element in such a material, and/or by using such a material between adjacent radiating elements or between a radiating element and a reflective ground plane, the physical size and/or the spacing of the elements may be substantially reduced without appreciable performance loss, thereby resulting in a more compact device that is particularly desirable for mobile applications. At least one exemplary such material is formed in layers and has electrical properties which are anisotropic and homogeneous and which vary as a function of frequency; the layers of such a material are preferably oriented such that the particular frequencies of radiation propagating through each layer are presented with high matched values of relative permittivity and relative permeability, and low values of dielectric and magnetic loss tangents.

Antenna design using a high index, low loss material

A circularly polarized phased array antenna system for both reception and transmission applications includes a plurality of planar radiating (or receiving) elements, a switching matrix for each radiating element, a beamforming network and a transmit/receive module. Each planar element includes 4.times.N radially disposed segments that may be selectively connected with the four modes of a circularly polarized signal such that two opposing segments function as the two respective arms of a dipole radiating element and two orthogonal such dipoles function as a crossed pair of dipoles for receiving or transmitting the circularly polarized signal. The switching matrix and the beamforming network cooperate to determine the polarization phase of the radiating element by commutating the four modes of the circularly polarized signal to any four orthogonal segments of the radiating element. The polarization sense may be changed between right-hand and left-hand circular either within the bandforming network, or by causing the switching network to reverse the two signal modes connected across one of the dipoles. If N is greater than 1, then by electrically connecting up to N-1 nearby segments to thereby increase the effective angle subtended by each arm, the bandwidth may be increased while still permitting the radiating element's polarization phase to be determined in increments equal to the angle subtended by one segment; by selectively using either an odd or even number of segments to define the effective angle subtended by each dipole arm, the relative phase of that element may be determined in increments equal to half the angle subtended by one segment.

Phased array antenna system using polarization phase shifting

Synaptic antennas or other radio frequency interactive systems variable in response to photon energy stimuli, are provided from a three-dimensional matrix of electrically conductive segments with photoresponsive devices selectively separating numerous adjacent segments from each other and alternatively interconnecting segments with each other in response to photon energy stimuli. Photon energy stimuli supplied to a first array of photoresponsive devices provide a first combination of interconnected segments constituting a first radio frequency interactive configuration in the matrix. Conversely, photon energy stimuli supplied to a second array of the photoresponsive devices provide a second combination of interconnected segments constituting a second radio frequency interactive configuration in the matrix. A third radio frequency interactive configuration in the matrix different from the first and second radio frequency interactive configurations may be provided by supplying photon energy stimuli to a third array of the photoresponsive devices, different from the first and second arrays, to provide a third combination of interconnected segments, and so forth.

Synaptic radio frequency interactive systems with photoresponsive

A multioctave, multifunction antenna system including three planar terraces each having four symetrically placed individual turnstile arrays. A first terrace includes turnstile arrays of a first relatively large size, the second terrace is axially spaced therefrom and includes four second individual turnstile arrays of a second size smaller than the first size. A third terrace includes a similar arrangement of four individual turnstile arrays of a third and smallest size. A ground plane for the arrays of the second and third terraces is included in the plane of the next larger arrays, the first terrace having a spaced ground plane in a separate plane. Between the planes of each terrace an absorbing material provides a lossy medium for broadbanding and reduction of the interaction among the arrays of any given terrace with those of the other terraces. The elements or lobes of each dipole of each turnstile is arranged for separate feed, permitting maximum flexibility in respect to the overall mode of operation, i.e., such as for polarization determination, monopulse, etc.

Multioctave turnstile antenna for direction finding and polarization

A multimode loop antenna arrangement for generating various radiation/reception patterns, the loop comprises a plurality of peripheral gaps which are fed through hybrid networks or the like for the production of specialized patterns, such as cardioid, mutually orthogonal dipole modes, and combination modes, such as the so-called turnstile configuration. The antenna is basically non-resonant unless separately tuned and is most useful where broadband operation and minimal size and weight are important.

Growing community of inventors

Chatsworth, CA, United States of America

Richard C Dempsey