Abstract: A radome diagnostic system comprises a rotatably mounted turntable having support memebers for supporting a radome in a radome support area on the turntable, and a scanning assembly on the turntable for supporting a probe antenna in the radome support area and for translating the probe antenna in perpendicular x and y directions to cover a predetermined planar scanning area. A reference antenna is mounted on the turntable to provide a reference signal, and both the reference antenna and the probe antenna are connected to a suitable receiver for receiving signals from them and for suitably analyzing the collected data. A transmitter is located at a position remote from the turntable to direct radiation towards a radome mounted on the turntable. The probe antenna will detect radiation as degraded or modified by the effect of the presence of the radome in the radiation path. The reference antenna receives unperturbed radiation.

Abstract: A circuit for coupling transitional energy from the output of a transmitting circuit to the input of a receiving circuit in advance of the normal connective path, which contains an inherent circuit time delay. Feed forward compensation circuitry is incorporated into a logic driver having control circuitry for receiving an input bistate data bit and providing power at an output at first and second predetermined voltage levels when an input bistate data bit is respectively of first and second states. The feed forward compensation circuitry is included in the control circuitry for modifying the response time of the control circuitry for providing output power in response to the input bistake data bit. Sensing circuitry is coupled to the control circuitry for detecting the level of current at the output and providing a corresponding current level indication.

Abstract: A system and method for detecting the positioning of an object wherein a driver generates an optical signal and intensity modulates the optical signal at a rate corresponding to the sum of N different frequencies. A transducer, responsive to relative physical positioning of the object, receives the intensity modulated optical signal and extracts a portion of the intensity modulated optical signal corresponding in intensity to selected ones of the N frequencies. A decoder, responsive to the extracted portion of the intensity modulated optical signal, generates a position signal according to the selected ones of the N frequencies in the extracted portion. The position signal is indicative of the relative positioning of the object with respect to the transducer.

Abstract: A logic driver having control circuitry for receiving an input bistate data bit and providing power at an output at first and second predetermined voltage levels when an input bistate data bit is respectively of first and second states. Sensing circuitry is coupled to the control circuitry for detecting the level of current at the output and providing a corresponding current level indication. The driver further includes overcurrent circuitry, responsive to the current level indication, for generating an overcurrent command when the output current exceeds a predetermined level. The control circuitry is responsive to the overcurrent command for disabling the output of power at the corresponding predetermined voltage level at the output.

Abstract: A fiber optic data bus that includes a multiplexer means for generating a plurality of optical signals and for intensity modulating each of the optical signals in response to a respective one of a plurality of input RF signals each at a different RF carrier frequency to provide a plurality of intensity modulated optical signals. A signal collection means combines the plurality of intensity modulated optical signals into a combined optical signal. A conducting means conducts the combined optical signal to a signal distribution means which distributes the combined optical signal to each of a plurality of output ports. A demultiplexer means extracts from a portion of one of the distributed combined optical signals an output RF signal substantially identical to a predetermined one of the plurality of RF input signals.

Abstract: A multi-octave thick dielectric radome wall which includes a dielectric slab having a pair of surfaces and a plurality of pyramidal-shaped dielectric elements mounted on at least one of the surfaces of the dielectric slab. The dielectric constant of the elements is typically greater than the dielectric constant of the slab. In an alternate embodiment, a second dielectric slab is provided adjacent to one of the first dielectric slab surfaces having the elements mounted thereupon with support means for supporting the second dielectric slab in a spaced apart relationship with the first dielectric slab.

Abstract: A spectrum analyzer subsystem for analyzing the frequency content of an RF signal including an optical source means responsive to an RF signal for generating a plurality of intensity modulated optical signals and a filter means responsive to each one of the intensity modulated optical signals for providing a plurality of output optical signals each corresponding to a respective one of the intensity modulated optical signals. Each output optical signal corresponds in intensity to the frequency content of an RF signal within a different predetermined frequency bandwidth. Detector means, which is responsive to each output optical signal converts each output optical signal into a corresponding electrical signal.

Abstract: An interconnection system for an electronic equipment rack containing a plurality of electronic equipment units mounted in drawers or slides slidably mounted in spaced parallel relationship on the rack. The system includes a rigid backplane panel for mounting across one wall of the rack and a plurality of spaced parallel conductors extending across the panel in a direction transverse to the equipment units. A plurality of mating connector assemblies are provided for signal communication between the electronic equipment units and the backplane conductors, and are mounted to extend transversely to the backplane conductors in alignment with the equipment units. The mating connector assembly is connected to the aligned equipment unit and includes signal conditioning devices for predetermined conditioning of electrical signals in the system, and conductors for connecting the signal conditioning devices to preselected ones of the backplane conductors.

Abstract: A bistatic VHF Doppler radar is utilized to detect and track one or more intruders crossing a large annular ring surveilance zone surrounding a central high security installation. A central omni-directional transmitter radiates the surveillance zone with a continuous wave (CW) signal. Predetermined ones of a plurality of receiver antennas circumferentially spaced around the surveillance zone receive a portion of the signal which is reflected by an intruder crossing the surveillance zone and a portion of the signal which is directly radiated from the transmitter antenna. The reflected signal portion may be received by antenna arrays each of which is controlled to form a null in its pattern toward the transmitter antenna to overcome direct signal overload. The direct signal portion may be received by stub antennas. Each antenna array and each stub antenna is connected to a separate channel of a dual channel receiver.

Abstract: A cable carrier/retractor for supporting, protecting and guiding a cable to an equipment drawer in a cabinet including a framework while at the same time allowing for addition or removal of cables without any disassembly of the mechanism. The carrier supports a cable from an entry position adjacent to the framework of the drawer to an exit position adjacent to the back panel of the drawer. The carrier generally comprises a first having an entry end for supporting a cable from the entry position to an intermediate position, and a second channel for supporting the cable from an intermediate position to the exit position, a hinged mount connecting the first channel to the frame, and an intermediate hinge for connecting the channels. In a preferred embodiment, a retaining hinge connected to a drawer-mounted slide member or the drawer back panel holds the exit end of the second channel in a position adjacent to the back panel.

Abstract: An optical RF bandpass filter employing a noncoherent optical carrier. The filter consists of a section of multimode optical fiber having a length equal to half the modulation wavelength with mirrors deposited at each end of the fiber. The fiber section functions as a resonant cavity for the intensity modulated light which is directed into the fiber and which exits at one end through one of the partially reflecting mirrors.

Abstract: A broadband optical spectrum analyzer analyzes RF frequencies by modulating a laser beam at its source with the RF frequencies. The modulated laser beam is collimated and directed to a reflection means where signal components of different frequencies are reflected at different angles. Rays of the same spectral range are collected and interpreted.

Abstract: A resilient, flexible elongate member forming a movable electrical contact is squeezed endwise by energizing a piezoelectric body supporting one end of the member. The mechanical advantage provided by this Euler lever construction permits the minute dimensional change in the piezoelectric body to open or close the relay by causing the member to bow outwardly so that its intermediate portion physically makes or breaks electrical connection with a fixed electrical contact. The relay provides improved signal integrity and isolation at lower power dissipation levels than solid state switching alternatives. Form A, B, C, and D and other contact variations are possible. A temperature compensated miniature package containing a plurality of such relays may also be constructed.

Abstract: A large objective lens is placed in a highly eccentric orbit about the earth. The orbit and orientation of the lens are carefully chosen so that it focuses light or other radiation from a preselected astronomical object into an image which slowly moves across the surface of the earth. A row of optical sensing units is located on the surface of the earth so that the image focused by the orbiting objective lens will travel substantially perpendicularly across the row during an observation. Output data generated from the sensing units may be multiplexed and fed to a real time processor which produces display signals. Each of the sensing units provides one scan line of the image being observed. The display signals are fed to a suitable display device which produces a picture of the preselected astronomical object. The objective lens may comprise a large flexible Fresnel zone plate or a flexible convex lens carried by a bicycle wheel-type supporting structure.

Abstract: A method of forming metallic patterns on a dielectric surface such as a radome surface that has a compound curve which includes the steps of coating the radome with a metal and then with a photoresist. An electrical pattern is formed on the photographic emulsion of a thin membrane that is used as a photo mask. A water soluble adhesive, which is non degradable to the exposure and development of the photoresist and the etching of the conductive surface is applied to the metallic surface and the photo mask is pressed into position on the adhesive to conform to the curvature of the radome. The photo mask is removed and the electrical pattern is provided on the surface by conventional developing and etching techniques to provide a clear, well defined pattern even in arrays wherein the pattern segments are of small dimension.

Abstract: A direction finding antenna system including a self-referencing interferometer for determining the direction of a source that emits plane wave radiation. The interferometer includes a slab of dielectric material for passing incident plane waves and for guiding coherent waves excited by the incident plane waves, whereby the guided waves interfere with the incident plane waves passing through the slab to form intensity fringe patterns, wherein the fringe spacing in a given dimension along the non-incident surface of the slab equals 2.pi.(K.sub.g -K.sub.o sin .theta.).sup.-1, wherein K.sub.g is the propagation constant of the dielectric material, K.sub.o is the propagation constant of free space, and .theta. is the angle between the normal to the incident surface of the slab and the direction of the incident plane waves.

Abstract: An angle filter for electromagnetic radiation having a predetermined wavelength .lambda.. The angle filter includes a planar-parallel pair of perforated conductive plates having arrays of periodic perforations. The perforations are spaced apart for creating grating lobes between the plates at the predetermined wavelength .lambda. at incidence angles greater than .theta..sub.G. All of the perforations in both plates are identical. The spacing between the perforations in both plates is identical. The plates are staggered so that the perforations in at least one dimension of one plate are aligned between the perforations in the corresponding dimension of the other plate for minimizing coupling between the plates at incidence angles somewhat greater than .theta..sub.G in a plane corresponding to the one dimension. The center-to-center spacing between perforations in the one dimension is equal to .lambda. divided by 2 sin .theta., wherein .theta. is an incidence angle greater than .theta..sub.G.

Abstract: A method and apparatus for measuring radiant energy scattering characteristics of a test panel of dielectric material over a circular arc are disclosed. The test panel is supported on a turntable at a position on the axis of the turntable. The turntable has a fist antenna radially mounted thereon for rotation therewith and directed toward the position of the supported test panel. The test panel support is rotated with respect to the turntable to selectively position the test panel at a predetermined incidence angle with respect to the first antenna. The turntable is rotated with respect to a second antenna which is in a fixed stationary position and directed toward the supported position of the test panel to selectively position the test panel at an incidence angle with respect to the axis of propagation of the second antenna that is equal to and opposite the predetermined incidence angle.

Abstract: A radome having arrays of thin strips of dielectric material on both the inside and outside walls of a conical shell defined by a sheet of dielectric material for compensating for the polarization dependent phase delay of the radome shell is disclosed. The strips of the outside array are supported edgewise on the outside wall and are normal thereto. The outside strips are equally spaced from each other, and disposed so that the intersection of lines extending therefrom is at the vertex of the shell. The strips of the inside array are supported edgewise on the inside strips wall. The inside strips are spaced from one another and tilted from the inside wall at an angle of approximately 45 degrees in a direction away from the vertex of the shell. Each of the inside strips is a frustum of a cone disposed with its axis along the axis of the shell. The tilt of the inside strips increases the transmittance bandwidth of the radome and further decreases dependence of phase delay upon the angle of incidence.

Abstract: A system for obtaining a vertical profile of water quality in a body of water is disclosed. The system includes a sensor for sensing predetermined characteristics of water and the depth of water at which the predetermined characteristics are sensed, a cable attached to the sensor for holding the sensor, and a winch assembly attached to the cable for deploying and retrieving the cable and the sensor in a body of water. The winch assembly includes a non-ventilated DC motor coupled to the drum for driving the drum to retrieve the cable, and for generating electricity during deployment of the cable in response to the torque on the motor created by the cable and the sensor during deployment, an electromagnetically released brake coupled to the motor for braking the motor when the brake is not energized, a battery for providing energy for the motor and the brake, and a motor controller coupled to the battery for providing constant voltage excitation of the motor and for controlling the brake.