Abstract: An FM-CW radar system with improved range discrimination and improved immunity to clutter, chaff, jamming and multiple target environments. The FM-CW apparatus involves a repetitive cycle including a first, constant-transmitted-frequency (monochromatic) transmission, a linear frequency upsweep as a second period and a linear frequency downsweep as a third period within each transmission frame. Pseudorandom coding is superimposed on the FM-CW waveform, a code word duration being selected to place the first Doppler ambiguity beyond the highest expected equivalent target velocity. The resulting range ambiguities are resolved by means of the unambiguous range-determining capability of the FM-CW feature.

Abstract: An antenna array consists of one or more slotted-waveguide, linear subarrays. Slots for radiation are cut in both narrow walls of each such waveguides, and PIN diodes across the slots are selectably forward and backward biased to effectively open the slots along one waveguide narrow wall while the others are closed and, alternatively, vice verse.

Abstract: A multiple port loop-coupler, commutating feed for a circular or cylindrical array. A rotor having a plurality of elongated coupling loops circumferentially spaced about an arc of its perimeter is fed from a strip line configuration excited at the driven central axis of the rotor. A plurality of elongated stater loops within essentially the same radial dimensions but extending throughout the full 360 degrees of the circular perimeter of the device continuously couples a changing fraction of the stater loops to the rotor as the latter is rotated. An output port is provided connected to each stater loop, and these output ports may then be discreetly connected to corresponding elements of a circular array or columns of elements of a cylindrical array.

Abstract: Apparatus is shown for controlling pulse width in pulsed, step-wise frequency modulated transmitters employing relatively long pulse widths and receiving pulse compression. Also disclosed is a pulsed pseudo-random coded radar system having fixed code word duration. Individual solid-state, RF power amplifier modules are paralleled, all spares included, and the full parallel group is operated at a power level such that individual units operate substantially below maximum power rating. RF solid-state device life is thereby increased. Failures of individual solid-state modules are recognized by a power monitor which operates to lengthen the pulse width in the FM staircase embodiment and to increase power supply input and, therefore, peak pulse power in the pseudo-random coded embodiment, thereby restoring average nominal transmitter power, notwithstanding one or more failed solid-state RF amplifiers.

Abstract: An annular rotary RF coupler for installation about a vertical support structure, particularly the mast of a ship. Two annular troughs are regularly divided in circumferential increments providing a cellular structure of individual waveguide cross-sections. A lower annulus remains fixed, the individual waveguide sections therein being fed from a power-divided, equal-phase, feed configuration. The oppositely facing upper annulus rotates with respect to the lower one about a common mechanical center of rotation of a mechanically rotating antenna system. Connection to the rotating waveguide sections may be through power combiner/divider means, or individual subarrays may be discretely connected to one or more waveguide sections in the rotating annulus. For power tapering across an antenna array aperture, the waveguide section dimensions in the circumferential direction within the rotating annulus are appropriately tailored.

Abstract: A submarine cable is terminated to a tail cable outside a repeater housing anchorage. A flexible shroud covers the joint and a cable stopper holds the main cable to a tear-shaped anchor member through which the tail cable passes.

Abstract: Termination device for anchoring a fiber optic cable, especially in a fiber optic cable submarine signaling system wherein the cable must be periodically interrupted and anchored to the housing of a repeater, or the like. A central cable or strength member of steel, for example, is built into the cable along with a plurality of optical fibers. A compression block accepts the cable through an axial bore which flares out into a conical shape. A pressure cone has an axially slotted wall to form a plurality of tines which tend to compress radially inward against the strength member of the cable actually inserted therein when the cone is axially compressed into the conical cavity of the pressure block. Individual optical fiber passages through the compression block flare out from the small end of the conical cavity and pressure cone. The compression block fits into a cup of insulating material, the cable entering through a bore in the closed end of the cup.

Abstract: A pulse compression radar which transmits a step-wise FM pulse and correlates at the receiver using a bank of delay lines (having progressively increasing delays) of the fiber optic type. One such delay line corresponds to each step of the frequency modulation program transmitted. The summed delay line outputs converted to electrical signals are summed to provide the compression desired. A suitably amplified stair-step received echo signal is applied to control the deflection of a Bragg cell illuminated from a laser source, the variable light ray deflection produced by the Bragg cell being focused progressively at the input of each of the discrete fiber optic delay lines. The same bank of fiber optic delay lines is employed in an oscillator loop, these delay lines being effectively electronically switched into place sequentially in the frequency determining feedback loop of the oscillator circuit.

Abstract: A system for elimination of transmitter (illuminator) leakage in a high duty cycle, pulsed, pseudonoise, semi-active missile guidance system. The missile has front and back receiving systems, and the illuminator signal extant at the rear receiver is used to develop a gating signal which turns the front receiver "off" during the time of arrival of the leakage signals at the front receiver. The receiver gating is automatically time adjusted as a function of missile range. Alternate reversal of the bi-phase transmitted code bits is offered as a means of reducing the "eclipsing" loss due to receiver gating out of useful signal return from the target being tracked.

Abstract: A fluid-type penetrator or feed-through device particularly adapted for conveying an optical fiber in a fiber optic signaling arrangement through an interface wall separating environments of greatly different physical (especially pressure) and/or chemical properties.A clearance passage considerably larger than the optic fiber is bored through the bulkhead separating the two different environments, and a guidance sleeve having a central axial bore only slightly clearing the diameter of the optic fiber is inserted therein. Pressure plugs also containing axial clearance bores are provided at high and low pressure sides of the arrangement, the low pressure plug being inserted by means of screw threads. The high pressure plug on a corresponding side of the bulkhead is automatically forced into tighter engagement in the counterbore into which it is inserted. Both pressure plugs include sapphire orifice members which have the characteristic of providing very small clearance for inserted optic fibers.

Abstract: A method and apparatus for eliminating multiple-time echoes from the output signal train of random PRF pulse Doppler radar system. A multiple-time echo is recognized by calculation of the absolute value of the difference between the last two phase pulses received in each range gate (bin). That absolute value is compared to the average of the preceding N absolute value. A multiple-time echo is present if the last absolute value is higher by a predetermined amount than the average of the preceding N absolute values. A logical switch provides automatic switching to substitute a previous phase pulse in a corresponding range gate when the phase pulse of a range gate is determined to be altered by presence of a multiple-time (non-coherent) echo signal.

Abstract: A machine for working generally tubular materials to perform deburring, pinch rolling and similar operations. The open end of the work is inserted over an idling roller mounted on the end of a first shaft. A second roller is rotationally driven on the end of a second shaft, and eccentric means controlled by separate (including manual) means are provided for varying the lateral clearance between the rollers to compress and effect rotation of the tubular work contemporaneously. A unique spur gear reduction arrangement includes a pinion gear on the driving NEMA C-face motor shaft which engages the larger ring gear. The ring gear is ball keyed to the shaft supporting the driven roller. An additional opening in the housing and shaft support casting is obviated, the ring gear being inserted through the motor face opening and moved laterally to engage the driven shaft over the keying ball in a driven shaft lateral bore.

Abstract: For aircraft equipped with ATCRBS and ILS, an identification and surface guidance system including a plurality of detection positions each including an interrogator and an auxiliary transponder located adjacent the runway and on opposite sides thereof, respectively. The interrogator is enabled through a signal cable from a remote location, such as a control tower, to produce the first of the discretely spaced pulse pair required to interrogate the ATCRBS equipment. The second interrogation pulse of the pair is generated by the transponder, which is activated by the radiated first pulse from the interrogator and includes an internal delay, such that this delay plus the transit time from the transponder serves to generate the second pulse of the pair if the aircraft to be interrogated is in the vicinity and on the pathway centerline or within a specified lateral tolerance therefrom.

Abstract: A planar array and associated apparatus providing polarization agility in radar systems. The array is composed of first and second pluralities of generally parallel, slot-radiator, linear arrays. The first group of linear arrays has radiator slots oriented at 45.degree. with respect to the axial (lengthwise) dimension of the linear arrays. The second group also has 45.degree. slots, but they are rotated 90.degree. with respect to the slots of the first group. First and second groups are interleaved, each group being excited in parallel, the first group directly from a transmit/receive port and the second from the same port but through a controllable phase shifter. The setting of the phase shifters of the array comprising the first and second groups of interleaved linear arrays produces a corresponding operating polarization. Each linear array is a length of coaxial transmission line with rectangular or square outer conductor, the slots being cut into the walls thereof.

Abstract: A high efficiency regulated heater power supply which avoids the interactive effects of varying magnetic field around the heater on tube operating parameters. The technique employed is to "chop" the low frequency (typically, 60 Hz) supply at a high frequency 10 kHz, for example, rate. Regulation is accomplished by sensing RMS voltage across the heater (filament) and adjusting the "chopping" duty cycle to maintain constant RMS heater voltage. The aforementioned magnetic field effects are prevented by synchronizing the "chopping" frequency with the tube pulse rate, such that the tube heater (filament) is actually deenergized and operating on thermal inertia only during tube pulsed operation.

Abstract: A sealed connector which can be used for making electrical connection underwater. The connector comprises two chambers one behind the other, the inner chamber containing an electrical connection terminal and being closed by a first diaphragm penetrable by a plug contact, the outer chamber being closed by a second diaphragm also penetrable by the plug contact, both chambers being filled with an electrically insulating grease, jelly or similarly viscous liquid.

Abstract: A range, angle, and Doppler (velocity) measuring radar in which a CW, PRC radar floodlights a volume of interest. A receiving antenna in the form of a linear array generally broadside with respect to the bisector of the volume of interest is commutated (sampled) element-by-element to provide a phase modulated received signal from which angle information may be derived. Autocorrelation of the PRC signal received against the transmitted code provides for range determination and a Doppler filter bank is provided corresponding to each discrete receiving angle, the outputs indicating range and velocity of a target at each discrete angle of reception.

Abstract: Apparatus for manufacturing commutators, especially for small electric motors. Commutator segments are separately inserted into a mold intermediary plate. The segments are inelastically deformed by a coaxially inserted tool before the molding process. The formation of webs of the injected plastic body material between commutator segments is avoided.

Abstract: An array (aperture) signal processor using surface acoustic wave delay lines for reordering of the received signals according to the prime number transform algorithm. The output of the processor is a radar response equivalent to forming a multiplicity of narrow beams essentially simultaneously. Reordering of the received signals is simply a matter of rearranging the hardwired connections to a first SAW delay line, and convolution of the reordered signals is achieved by phase weighting the taps in a second SAW delay line which forms part of a transversal filter.

Abstract: A device for use in submarine cable systems, particularly for fiber optic cable systems. A water-tight enclosure or housing is provided which is accessible for maintenance purposes. The device, which is of generally tubular shape, provides termination chambers at either end attached to bulkhead members for the introduction of cables and their mechanical termination therein. The fiber optic elements themselves are passed through the bulkhead members in penetrator subassemblies to reach the interior chamber. An axially split cylindrical shell has at least two arcuate members which fit together and nest on circumferential shoulders on the bulkhead members which have radial depths equal to the material thickness of the arcuate members. An outer sleeve slides axially over this assembly, circumferential seals providing water-tight contact between the outer sleeve and the bulkhead members.