Abstract: An enclosed antenna assembly having a non-rigid, floating connection between an aluminum tray and a radome along the length of the assembly. The non-rigid, floating connection along the length of the antenna assembly provides a seal that is not damaged or degraded as a result of thermal expansion and contraction of the dissimilar materials. The tray and radome are joined along their length by a tongue and groove type connection, which allows free movement along the major axis. A top end cap provides the only rigid connection between the tray and the radome. A bottom end cap is fastened only to the radome. The design of the keyway and the top end cap prevent direct water intrusion. The bottom end cap includes weep holes to allow condensation to escape from the interior of the antenna assembly.

Abstract: A 90.degree. coupling circuit cascaded with a pair of hybrid mode latchable phase shifters provides polarization agility for an RF radiator module of the type typically used in a phased array. For example, such radiator modules typically may utilize an active microwave integrated circuit (MIC), a monolithic microwave integrated circuit (MMIC) or a passive reciprocal hybrid mode element (RHYME) circuit. These circuits are arranged to provide duplex RF transmit/receive functions with controllable phase shifts at each radiator site in a phased array. By appropriately setting the two controllable phase shifters to different combinations of phase shifts (e.g., 0.degree. and/or 90.degree.) to a dual orthogonal mode radiator, different spatial polarizations for RF radiator transmit/receive functions can be defined. The radiator itself may include a square or circular waveguide including, in some cases, a reciprocal dielectric quarter-wave plate and a non-reciprocal ferrite quarter-wave plate.

Abstract: A low cost, light weight, high performance phase shifter mounting structure which allows high density packaging of phase control modules for phased array antennas. The mounting structure is a bimetallic sandwich design in the shape of an I-beam having a top flange for mating to radiating elements, a bottom flange for mating to a feed network, and a center web for mounting phase control modules. The I-beam is formed from a single piece of laminated stock comprising an outer layer of aluminum and a core layer of titanium forming an anisotropic thermal expansion composite material. The titanium center web matches the coefficient of thermal expansion of the typical ferrite, MIC, or MMIC phase shifter and driver circuits. The aluminum flange material allows easy machining of microwave transitions at each end of the I-beam and matches the expansion of typical radiating element structure and feed networks.

Abstract: A miniaturized waveguide mode ferrite RF phase shifter is efficiently transitioned to a matched impedance microstrip transmission line mode at either end to result in an ultra small, efficient and lightweight essentially "planar" phase shifter device having a single ferrimagnetic toroid.

Abstract: An RF phase shifter combines a non-reciprocal ferrite 180.degree. stage with one or more reciprocal diode phase shifting stages to produce an essentially planar phase shifter that is ultra small, efficient and lightweight. Such phase shifter elements may be used in phased arrays to produce an array offering major improvements over existing planar substrate all diode phase shifters while maintaining the phase gradient between array elements and without switching the ferrite shifter between the transmit and receive modes.

Abstract: A reciprocal transceiver to radiator coupling circuit uses both microstrip and waveguide modes of RF signal transmission (including a pair of nonreciprocal hybrid mode phase shifters) to gain size and weight advantages useful in feeding large scale phase arrays. At the same time, the radar cross section of such array apertures is reduced by arranging separate nonreciprocal receive and transmit branches of the circuit to route spurious intra-circuit reflections of incoming RF signals to a matched termination.

Abstract: A monostable circuit with device-status feedback control to an external timing terminal is used to controllably change the magnetization state of a ferrite phase shifter core. A pair of such bistable circuits with suitable feedback controls permits a single command pulse of controlled duration to controllably both reset a ferrite core to a saturated magnetic state and then subsequently set the core to a desired non-saturated magnetization state (corresponding to the time duration of the single command pulse). By addition of suitable steering circuits, the controlled resetting and setting of one or more pairs of such ferrite cores can also be achieved using the same single command pulse. The ability to both reset and set plural ferrite phase shifter cores with but a single command pulse of controlled duration permits considerable simplification of beam steering control wiring for a two-dimensional phased array of RF radiators (e.g., so as to provide electronic beam steering control).

Abstract: A miniaturized waveguide mode ferrite RF phase shifter is efficiently transitioned to a matched impedance microstrip transmission line mode at either end to result in an ultra small, efficient and lightweight essentially "planar" phase shifter device having wide application in the microwave industry.

Abstract: A distributed parallel processing architecture for electronically steerable multi-element RF array antennas provides real time rapid array updates with decreased hardware cost and complexity. The array is subdivided into plural sub-arrays (each sub-array has more than one RF radiating element) and a phase shift interface electronics ("PIE") device is provided for each sub-array. Parameters specific to the RF elements within the sub-arrays are preloaded into the corresponding PIE. Pointing angle and rotational orientation parameters are broadcasted to the PIEs, which then calculate, in parallel and in a distributed processing manner, the phase shifts associated with the various elements in their corresponding sub-arrays. Linearization, phase compensation for various factors (e.g., operating frequency, measured characteristics of individual RF elements, feed line delay to individual elements, etc.

Abstract: A fast switching ferrite phase shifter is disclosed featuring both reciprocal operation and fast switching speeds. Reciprocal operation in transmit and receive modes is achieved by employing two latching, toroidal non-reciprocal phase shifters; one for transmitting and one for receiving. The exemplary embodiment utilizes input and output circulating devices which include a Faraday rotator and septum polarizer for appropriately routing signals through one or the other of the phase shifters depending upon the direction of input signal propagation. The phase shifter achieves fast switching since the latching, toroidal, non-reciprocal phase shifters are transversely magnetized devices and are disposed entirely within a waveguide so that the generated magnetic field is confined entirely within the waveguide. The phase shifters do not intersect the waveguide walls and, thus, during a switching operation, the magnetic field is not switched through conductive waveguide walls.

Abstract: Impedance matching between a waveguide circulator and its input/output ports is achieved by properly dimensioning a gap formed between a ferrite circulator element inside the waveguide circulator and at least a portion of the input/output port aperture itself. Typically, the I/O port aperture has at least a portion which is of lesser height dimension than the internal waveguide circulator cavity. Ridge waveguide or ridge-to-rectangular waveguide adaptor blocks, or the like, may emanate from such input/output circulator apertures.

Abstract: A conductive waveguide structure has a central cavity of full height and input/output ports of a second reduced height emanating therefrom. A smaller ferrite circulator element is centrally disposed within the cavity and has outer extremities spaced from the inner edges of the reduced height input/output ports by a predetermined gap dimension "G" which is chosen to achieve an appropriate impedance match between the impedance of the ferrite element and the higher impedance of the wavguide without the necessity for the usual quarter-wave dielectric impedance matching transformer sections.

Abstract: A compact adaptor is provided for making transition from ridged waveguide to rectangular waveguide while simultaneously imparting spatial reorientation of associated electric and magnetic fields. The adaptor is especially useful for feeding a phased array of radiating slots (or other structures) where adjacent radiating structures are preferably spaced from one another on the order of a half wavelength and fed with the magnetic field vectors oriented parallel to such inter-element array spacing dimensions. In the exemplary embodiment, a transition from double-ridged waveguide to rectangular waveguide is effected through an electrically short (e.g., 1/8th to 1/4th wavelength) non-resonant cavity using oppositely tapered continuations of the ridged waveguide walls (acting as a TEM parallel transmission line) to opposing walls of a rectangular waveguide port which is spatially oriented transverse to the ridged waveguide.

Abstract: The present invention is for an apparatus and method of fast-switching a dual-toroid microwave ferrite phase shifter. A first circuit is provided for controllably switching the ferrite in one of the toroids between a saturated and partially saturated states. A second conduit is provided for controllably switching the ferrite in the other of the toroids between a saturated and partially saturated states. A control circuit is provided for controlling the first and second circuits such that the ferrite in at least one of the toroids is maintained in the saturated state at any given time such that any desired phase shift may be achieved with only one switching operation for each toroid. The present invention provides new reference states such that there are two reciprocal phase states for any given phase state such that a reciprocal phase state may always be achieved with only one switching operation for each toroid.

Abstract: Apparatus and method is disclosed for determining the position of a mechanical part from among a plurality of discrete positions. An inductor with a saturable core is placed in proximity to each position so that a permanent magnet attached to the part saturates only the core nearest the part, thereby reducing the inductance of that particular inductor. The variation in inductances are detected by comparing voltage rise times across a current limiting resistor serially connected to each inductor. The voltage across the resistor connected to the inductor nearest the position of the part will have the shortest rise time. In a two position embodiment, the variation in rise times is detected by a R/S flip-flop with each input coupled to one each of the inductors.

Abstract: A microwave latching ferrite device is provided of the type associated with microwave transmission lines for effecting a phase shift or switching of the microwave signal being propagated. Driving means is provided for a latch winding of the ferrite device in the form of a blocking oscillator coupled between an input and the latch winding. The blocking oscillator includes a power transistor and a toroidal transformer coupled thereto. In response to a trigger pulse on the input, the blocking oscillator generates a single latch pulse on the latch winding, which is effective to change the degree of magnetization of the microwave ferrite device.

Abstract: A latching ferrite phase shifter having a ferrite toroid is provided with inexpensive means for adjusting its magnetization to account for manufacturing inaccuracies and temperature changes. A small permanent magnet is mounted externally of the transmission line in which the ferrite is positioned. The permanent magnet applies parallel fields to the opposite sides of the toroid, selectively reducing magnetic flux density on one side.