Abstract: The invention relates to a method for producing low cost integrated microwave assemblies, where a photoresist layer is deposited onto a substrate, a portion of the photoresist is selectively removed, a first conductive layer is applied, and, a second portion of the photoresist is removed leaving isolation walls and cavities. Electrical components are placed in the cavities and a first dielectric layer fills the cavities. Vias are created in the first dielectric material exposing the electrical contacts, a second conductive layer is applied into the vias and over the first dielectric material. The second conductive layer is patterned by removing a portion of the second conductive layer creating a signal line pattern in the second conductive layer.

Abstract: A detector 50 is included in a laser apparatus for generating a high energy laser beam to protect against the uncontrolled escape of the high energy laser beam from its prescribed optical path 14. The high energy laser beam proceeds along the optical path 14 and is directed to a work site 44 by a series of reflective surfaces in its path 26 and 30. The series of reflective surfaces function to change the path 14 of the beam 32 from the generating source to the work station 44. Associated with each of the reflective surfaces is a detector 50 which comprises a conductive frame 51 having a front face 52 and a back face 54. The back face 54 is equipped with a thermal sensor 60 which is positioned in a base portion 64 of the heat conductive frame 51. The detector is equipped with cooling means 58 and 66 for maintaining the threshold temperature.

Abstract: A solid state saturable absorber (SSSA) is formed from a slab of solid state material, such as Cr.sup.4+ : YAG. Optical distortion caused by the absorption process can be minimized by confining absorption to portions of the solid state slab which can be cooled efficiently. In accordance with an important aspect of the invention, the use of the SSSA in accordance with the present invention allows the repetition rate, pulse width, and energy level of the laser output pulses to be controlled by way of optical pump sources, such as a diode array. The solid state slab material allows for zig-zag propagation and thus, averaging of the thermal gradients caused by absorption, optical pumping and cooling which results in relatively low thermal lensing with virtually no birefringence and therefore allows for passive Q-switching applications in relatively high brightness laser systems.

Abstract: An advanced solar simulator illuminates the surface a very large solar array, such as one twenty feet by twenty feet in area, from a distance of about twenty-six feet with an essentially uniform intensity field of pulsed light of an intensity of one AMO, enabling the solar array to be efficiently tested with light that emulates the sun. Light modifiers sculpt a portion of the light generated by an electrically powered high power Xenon lamp and together with direct light from the lamp provide uniform intensity illumination throughout the solar array, compensating for the "square law" and "cosine law" reduction in direct light intensity, particularly at the corner locations of the array. At any location within the array the sum of the direct light and reflected light is essentially constant.

Abstract: A polarizer/modulator assembly (10) including a polarizing unit (12) and a modulator unit (14) that are selectively and independently positionable within a resonator cavity of a solid state diode slab laser. The polarizing unit (12) includes a pair of polarizing elements (32, 34) positioned in a "V-shaped" configuration so that both elements (32, 34) are positioned at Brewster's angle with respect to the beam path to combine to polarize the light in the same direction. The combination of the polarizing elements (32, 34) eliminates beam deflection when the polarizer unit (12) is inserted into the beam path. The polarizing elements (32, 34) are mounted in a metal housing (30) that captures rejected light from the polarizing elements (32, 34). The housing (30) includes a cooling tube (52) to control temperature of the housing (30) during temperature build-up caused by the rejected light.

Abstract: A damped latch mechanism 116 is provided for a telescoping structure 10 including an inner tubular member 114 slidingly received within an outer tubular member 112. A first latch member 122 is coupled within the one tubular member 114 and a second latch member 126 is coupled to the other tubular member 114 so as to selectively interfere with the first latch member 122 to prevent the inner tubular member 114 from moving in an axial first direction relative to the outer tubular member 112. A fluid chamber 134 is provided on one of the first and second latch members 122, 126 opposite the other of the first and second latch members 122, 126. A magneto-rheological fluid 136 is disposed within the fluid chamber 134 to absorb shock between the first and second latch members 122, 126.

Abstract: A microstrip switch includes N-input switch arms and an output port formed from a microstrip transmission line. Each input switch arm includes one or more p-i-n diodes. The input switch arms as well as the output port are connected at a radially combined center patch. In order to improve the insertion losses at millimeter wave frequencies, the center patch is air suspended in order to reduce the parasitic shunt capacitance in order to extend the low pass frequency response of the switch.

Abstract: A waveguide to microstrip transition (124) formed in a multi-layer substrate (208) is disclosed. The waveguide to microstrip transition (124) may be incorporated into a hermetically sealed package including a metal base (202), a multi-layer circuit (208), a metal ring (206), and a metal cover (204). The multi-layer circuit (208) has at least a first dielectric layer (230), a second dielectric layer (222), and a first conductive layer (218) disposed between the bottom side of the first dielectric layer (230) and the top side of the second dielectric layer (222). The multi-layer circuit (208) includes a waveguide (234). An electromagnetically reflective material (236) coats the walls of the waveguide (234) to allow signals to propagate by reflection through the waveguide (234) toward the first dielectric layer (230). Plated through vias (126) are located in at least the first dielectric layer (230).

Abstract: A spacecraft structure using functionally independent modules assembled around a lightweight core structure to provide a vehicle that is lighter, uses less volume, and is easier to design, manufacture and test than a conventional spacecraft. In the disclosed embodiments, the modules are formed on generally flat panels, which serve as thermal radiators. The modules extend radially from the core structure and are attached to the core structure either in coplanar rows that extend axially along the core structure or in a coplanar set that extends circumferentially around the core structure. Interconnection between modules is achieved through a backbone interface, through which the modules are connected to the core structure. A large number of variant configurations may be implemented using the modular approach, by selecting a core, components and modules of number and size to meet mission requirements.

Abstract: A photosensitive photoresist material which is effective for use as an ion etch barrier layer after patterning. The photoresist composition includes the reaction product of a compound having the general formula R.sub.1 --COO--(CH.sub.2).sub.n --O--R.sub.2 and a silylating agent.

Abstract: A novel IC chip packaging construction in which the chip package materials are selected such that their thermal linear expansion curves are closely matched over the full operating temperature range of the IC chip. The IC chip packaging construction includes a metal base and cover for enclosing the IC chip and a pair of insulating frames for hermetically sealing the IC chip in the chip package. A plurality of input/output leads make electrical connections with the IC chip through fine wires that are soldered to the leads and to contact areas on the IC chip. The metal base and cover and the input/output leads are fabricated from copper and the insulating frames are fabricated from Fotoceram.RTM. 160, which has a thermal linear expansion curve that closely matches that of copper over the full operating temperature range of the chip. Accordingly, the problems of differential expansion rates due to temperature variations for wafer size or very large scale IC chips are greatly minimized.

Abstract: A multi-focus reflector antenna for providing a plurality of antenna patterns from a single reflector structure eliminates the need for multiple reflector antennas on a single spacecraft. The multi-focus reflector antenna includes a plurality of at least partially overlapping reflecting structures on a single support structure, each reflecting structure having a focal point and a focal axis. A plurality of RF signals radiate from the focal points, at least one of which passes through at least one of the plurality of reflecting structures and is incident upon another of the plurality of reflecting structures. The plurality of reflecting structures then direct the plurality of RF signals along the plurality of focal axis and generate a plurality of antenna patterns. The multi-focus reflector has applications in communications systems and more particularly, in satellite voice and data communications, and other RF type signals.

Abstract: The present invention provides a laser tracking system including a laser generator for generating a beam of laser energy, a beam steerer for steering the beam of laser energy such that it moves in a search pattern, and a receiving device that receives laser energy reflected from a targeted object and that causes the beam steerer to vary the search pattern in response to the reflected laser energy. A tracking method associated with the laser tracking system includes the steps of generating a beam of laser energy, steering the beam of energy in a search pattern, detecting a hit spot formed from laser energy being reflected from a targeted object, diminishing the size of the search pattern in response to the detection of the hit spot, and focusing the diminished search pattern on a feature of the targeted object corresponding to the hit spot. The laser tracking system and associated method presented provide a number of advantages over conventional tracking systems.

Abstract: A multiple altitude satellite relay system is disclosed in which Medium Earth Orbit satellites are continuously linked with at least one geosynchronous satellite to provide uninterrupted relaying of messages and data. The Medium Earth Orbit satellites are synchronized with the geosynchronous satellites to produce continuous links. A parameter to achieve the synchronization involves the positions of the Medium Earth Orbit satellite relays relative to the positions of the geosynchronous satellite relays. Another parameter to achieve synchronization involves the ratio between the orbital periods of the geosynchronous satellite relays relative to the orbital periods of the Medium Earth Orbit satellite relays. These parameters may be further adjusted to provide continuous links above the horizon of the earth.

Abstract: A double forward DC-to-DC converter with soft-PWM switching provides two voltage pulses to the output low-pass filter within one switching cycle (hence, the name double forward). The double forward DC to DC converter includes a transformer having a single primary winding and a two secondary windings. A main switch, under the control of a PWM control circuit, is connected is series with the primary winding. An auxiliary switch is coupled across with the main switch by way of a resonant capacitor. The resonant capacitor and auxiliary switch are used to automatically reset the transformer core while the main switch is on back to the voltage source connected to the transformer primary. A diode and snubber capacitor is connected across the drain-source terminals for both the main and auxiliary switches for minimizing switching losses. The current mirror used in prior art is abandoned in order to avoid the locked-up mode of operation.

Abstract: There is provided an apparatus (10) for isolating an operating device against multi-dimensional disturbances which includes a series of spring assemblies (12) that are affixed between a support platform (14) and an operating device (16). The series of spring assemblies are affixed to a support platform (14) and mounted in three paired units to provide global isolation of the operating device against forces that act in five directions. Each spring assembly is equipped with a first and second set of spring elements (20) and (22) which absorb disturbance forces acting in an axial direction. The spring element (22) is a damping unit (30) which dampens the lateral vibrational forces caused by dynamic imbalance of the vibration-generating source. Included with each spring assembly is a load diverter (50) which serves to insulate the operating device against the sudden high vibrational forces that might be incurred during the launch of a satellite during the first minutes of the launch.

Abstract: A high energy chemical laser capable of being operated in an aircraft to interdict and destroy theater ballistic missiles is provided. A key to the chemical laser of the invention is the use of individual chemical lasers whose individual photon energy outputs can be combined into a single high-energy laser beam.

Abstract: A new electrical connector system employs two printed circuit board type connector components (1 & 3), each containing a plurality of plated-on metal lines (11 & 13) running along the board in parallel, and a replaceable contact element (9), termed an interposer, that is sandwiched between those printed circuit boards. The interposer contains malleable electrical contacts (15 & 17) on each side that extend electrically from one surface to the other and serves as a contact bridge for those connector contacts. The interposer is formed as a thin insulator strip and metal bumps on the top and bottom sides of the strip serve as the electrical contacts. Bridging connection for metal bumps on the top side with associated bumps on the bottom side is served with plated-through holes (16). The metal bumps are of Indium and Tin that is covered by a flash of Gold. Ancillary to the described connector, a new method for constructing an electrical connector is also presented.

Abstract: A composite laminate structure, and a method for its fabrication. The structure includes a syntactic core layer (10) including an epoxy system catalyzed by a Lewis acid, and two face skin layers (12), each of which has multiple graphite fibers laid up in a polycyanate matrix resin catalyzed by cobalt. After thermal curing, the laminate structure has the unusual, but highly desirable property that it is compliant enough to be conformed at room temperature to a different shape, without damage to the structure. The structure may be later conformed to other shapes or conformed to its original shape, again without damage. Structures of unusual shapes can, therefore, be easily fabricated from sheets of the laminate material formed in one (1) convenient initial shape, such as a flat panel.

Abstract: A reflection reducing directional coupler provides an output signal from a coupled signal while reducing the effect of an input signal. The directional coupler provides circuitry to divide, phase delay and vectorially add signals to provide coherent output and coupled signals and reduce reflected signals. The directional coupler also provides the capability to input a calibration signal into a system while mininimizing the effect of the calibration signal on the output signal.