Other

Ford Aerospace & Communications Corporation

Valentine Research Inc.

Harry J Gould

Michael D Valentine

Stephen Ray Scholl

Keiji Kawaguchi

Coaxial waveguide apparatus for conducting radio signals within a range of frequencies including an waveguide having an open end and a rear wall opposite the open end positioned along an axis of the waveguide and defining a waveguide cavity with a fundamental waveguide mode within the waveguide. The waveguide is constructed with a cutoff frequency for the fundamental waveguide mode which is at least 95% of the lowest frequency for the apparatus. A center conductor is positioned within the waveguide cavity and along the axis of the waveguide so that the center conductor and the waveguide define a coaxial waveguide cavity.

Coaxial waveguide feed with reduced outer diameter

A multi-feed, multi-band antenna includes a parabolic dish reflector, a plurality of four-port feeds, and may also include one or more orthomode two-port feeds. Each four-port feed is constructed to conduct multiple frequency bands and multiple polarized RF signals within each of the bands. A mounting structure mounts each of the feeds at a different position in a line and in a plane parallel to the rim of the reflector. The four-port feeds are of a size which allows them to be mounted adjacent each other and two degrees apart. The mounting structure positions the feeds at a distance F from the reflector. The diameter D of the reflector and the distance F have a relationship such that F/D is less than approximately 0.5.

Multi-feed multi-band antenna

A novel frequency scheme for a police radar detector enables improved sweeping of the X, K, K,and K,radar bands. The novel frequency scheme requires two initial frequency conversions for detection of the X, K and K,radar bands and a single initial frequency conversion for the K,radar band with single initial frequency conversion being enabled by disabling the second mixer. During sweeping of the X, K and K,bands, selectable, i.e., upper or lower, sideband suppression is employed to reduce undesired image sidebands and noise prior to the second frequency conversion. In addition, noise at the second IF frequency is reduced to prevent this noise from feeding through the second mixer into the second IF amplifier. During the K,band sweep, the second mixer is bypassed and shunting of signals at the second IF frequency is disabled so that these signals enter the second IF amplifier.

Police radar detector

Electronically adaptable polarization antenna feed apparatus for receiving any sense of linear polarization or for receiving either sense of circular polarization. The circuit makes use of variable gain amplifiers and/or variable attenuators in each of two orthogonally polarized paths. The signal to noise ratio of a desired polarization sense is maximized by adjusting the amplitude or gain in each path to a desired ratio. If desired, polarization components from the two probes may be combined so that orthogonal polarization senses from two frequency reuse signals be used simultaneously. The apparatus may be used with linearly polarized signals and with circularly polarized signals.

Electronic variable polarization antenna feed apparatus

Waveguide OMT, which can be utilized as an antenna feed, has two orthogonally polarized coaxial ports extending through the back wall of the waveguide. Cross coupling between the probes is minimized by locating the point of entry through the back wall and orienting each probe such that it couples to a primary waveguide mode, but does not couple to the first higher waveguide mode, or, for coaxial waveguide, does not couple to the TEM mode.

Dual waveguide probes extending through back wall

A processing system for microwave signals including a conductive housing having a waveguide probe for the input, a coaxial output connection and a section for receiving a microwave integrated circuit therein. The section contains two high impedance recesses therein, each of which is spaced a quarter-wavelength at microwave frequencies from the input and output portions of the integrated circuit. The high impedance recesses, reflected to the input and output sections, provide low impedance coupling therebetween for microwave signals. A dielectric member is interposed between the ground plane of the integrated circuit and the conductive housing to provide dc isolation therebetween and enable a single polarity voltage supply to establish the bias and operating voltages for the microwave integrated circuit.

Conductive housing and biasing system for microwave integrated circuits

Apparatus for separating a radio frequency (rf) ground plane from a metal housing in which a circuit board is disposed includes an rf choke and a dielectric layer for separating the housing from the circuit board.

Apparatus for separating rf ground plane from housing

A septum polarizer offering an exceptionally low axial ratio over a wide frequency band. A first trapped mode resonator or resonator pair is inserted in the circularly polarizing waveguide within the same plane as the septum and tuning screws to create a desired resonant response at a frequency lower than the cutoff frequency of the polarizer. Optionally, a second pair of trapped mode resonators is inserted in two opposing waveguide walls that are orthogonal to the septum, to create a desired resonant response at a higher frequency than the upper frequency limit of the polarizer. The resonators serve to flatten the phase response of the polarizer throughout its passband, thereby maximizing the purity of circularly polarized radiation produced thereby.

Growing community of inventors

Mesa, AZ, United States of America

Harry J Gould