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A microwave interferometric technique was developed and integrated with several experimental arrangements for detonation physics studies. The interferometer records the Doppler shift of reflections associated with moving material discontinuities and ionization fronts. The analysis of those Doppler shifts provide quantitative velocities which are useful in the development and verification of physical and theoretical models used to depict the processes. Initial circuit criteria such as impedance matching, dielectric measurements, and waveguide modes are considered. The interferometer has been applied to detonation velocity measurements, detonation transfer tests, gap testing, and piston driven compaction experiments. In addition to the relatively simple analysis used to obtain these results, investigations into higher resolution data reduction aided by computer synthesis and Fourier transforms are also discussed.

A millimeter wavelength solid dielectric waveguide having either and undulating or roughened outer surface is disclosed. As configured, and properly designed, for the wavelength of interest, the non-cylindrical surface will not have any deleterious effects on the electromagnetic properties of the dielectric waveguide. Moreover, the novel surface treatment will greatly increase the amount of heat energy that can be dissipated by radiation and convection from the dielectric waveguide thereby increasing its power handling capability., Supersedes PAT-APPL-746 483-85.

An electric wave operating device for efficiently coupling electromagnetic energy from a waveguide into a dielectric element or vice versa. A guide horn portion is chosen for radiating in the primary HE11 mode and designed to have a predetermined HE11 mode farfield radiation pattern. A dielectric member is securely disposed with one end in the plane of the aperture of the waveguide horn with the dielectric member having a predetermined HE11 mode farfield radiation pattern substantially equal to the farfield radiation pattern of the horn. PAT-CL-343-785. (JES), Supersedes PAT-APPL-859 109-86, AD-D012 430.

An electrically short, omnidirectional antenna formed with a strip conductor helically wound about the outside of a cylindrical ground plane. A layer (ideally, a very thick layer) of a nonconducting material preferably with a low dielectrical constant (i.e., epsilon approx.= 1.0) separates the microstrip from the ground plane. (Author), Supersedes PAT-APPL-080 596-79.

An improved self-powered vehicle detector (SPVD) uses a two-axis magnetometer in conjunction with digital nulling loops to sense a vehicle's magnetic signature and then telemeter vehicle presence information to a roadside receiver. The SPVD system includes a tone code transmitter and an omnidirectional microstrip antenna to simplify installation and maintenance of the SPVD. (Author)

This invention relates to antennae and more particularly, to omnidirectional microstrip antennae. A short, vertical rod is the classic omnidirectional antenna. It is omni-directional in a plane perpendicular to its longitudinal axis, vertically polarized in that plane, and may be easily matched with the impedance of ancillary equipment stages. Characteristically, a vetical rod is inefficient, does not remain tuned when placed in different media of radiation, and is particularly sensitive to nearby sensors, oscillators, and transmitters. While two orthogonal vertical loops may be used to provide the proper pattern (i.e., omnidirectional) and desired polarization, interactions between loops detracts from the performance of the antenna. Also, efficiency is low when loops are small compared to the operating wavelength. The noun 'ground plane' denotes a conducting or reflecting plane functioning to image a radiating structure. (Author)

A detector for non-destructive sensing of binary information at a selected location along a domain wall of a thin magnetic film strip. Voltages are applied across a set of contacts arranged along the margin of the strip and the value of the voltage measured at an arranged, centered contact indicates the presence or absence of a Bloch line-crosstie pair at that location. (Author), Supersedes PAT-APPL-720 295-76, AD-D003 125.

A conformal electronically scanned antenna array system utilizing an inverse Butler matrix in combination with directive antenna elements. The system provides a simple and inexpensive device for scanning an elemental array without the problems of output frequency shift or mutual coupling between antenna elements. (Author), Supersedes PAT-APPL-581 470-75.

A microstrip board comprising a gold film which contains about at least 1/2 weight per cent of aluminum bonded to a non-electrical conducting oxide is prepared by simultaneously evaporating the gold and aluminum onto the non-electrical conducting oxide and thereafter optionally heating the film thus formed. (Author), Supersedes PAT-APPL-191 292-71.

The patent describes a circuit for providing accurate timing pulses to steer an antenna array. A Gunn device coupled at the input of each transmitting element supplies a single pulse at predetermined time intervals to the element enabling time delay steering of the antenna array.

The publication contains a simple non-mathematical introduction to the theory of the Gunn oscillator and L.S.A. oscillator. The difficulties that have occurred in the fabrication of devices and materials are discussed. Predictions of the commercial availability of devices in the future are made. (Author)

One object of the patent is to provide Gunn devices, or the like, electrically connected in series and thermally connected in parallel. Another object is to provide a plurality of Gunn devices having ease of fabrication. A further object is to provide a plurality of Gunn devices which operate satisfactorily when connected in series. Briefly, these and other objects of the patent are attained by providing a plurality of Gunn devices fabricated along a single layer of active semiconductor material. Corresponding ohmic contacts located on each side of the semiconductive layer overlap to define a plurality of Gunn devices which are electrically connected in series and thermally connected in parallel. If desired, the Gunn devices may be fabricated such that the plurality of devices operate in phase.