Abstract: A frequency synthesizer or programmable multiple frequency source which uses a voltage-controlled oscillator (VCO) responsive to an independent control variable. The VCO is also responsive to control from an error loop circuit which derives an additional control voltage as a result of comparing the VCO frequency at any time with one of the phase delay multiples of a fiber optic delay line. The independent variable used to select an overall frequency desired controls the VCO directly to an approximate frequency and the fiber optic delay line and error generating loop associated therewith operates as an automatic vernier on the VCO to bring it into phase-lock with the nearest frequency which is a multiple of the reciprocal of the fiber optic line delay time.

Abstract: A CW pseudo-random-coded (PRC) radar system including a triple-clock arrangement. The three slightly different clock frequencies are sequentially employed to generate the bi-phase coded RF transmissions and the received echo signals are separately bi-phase de-modulated by code bit. Clutter filtering and sampling in both I and Q channels by a commutating element are employed. Video processing, preferably of the FFT type, is provided as is range-ambiguity processing. The system provides resolution of range ambiguities over a long total range permitting the PRC word length and other system parameters to be optimized for elimination of Doppler ambiguities.

Abstract: A digital compensator for radar transmitter instabilities for use in a digital MTI system. The I and Q coherent phase detector outputs are continuously monitored for phase, amplitude and timing instabilities and arithmetic correction signals are generated and applied to the digitized received signal values to compensate for these instabilities which are particularly characteristic of pulsed magnetron transmitters, for example.

Abstract: A device for generating a repetitive, highly-linear, frequency ramp. A voltage controlled oscillator responds to a ramp generator to produce the desired frequency modulation, and means are included for modifying the ramp amplitude vs. time shape as a function of the variation of instantaneous values of the frequency ramp from the linearized ideal.

Abstract: A simulated Doppler navigation beacon system providing second order spatial diversity with respect to excitation of its commutated 2-dimensional main (coordinate) array and a linear reference array. For elevation measurement, the main array excitation is advanced in elevation, one element at a time during each scan cycle, but the lateral (horizontal) excitation is varied pseudo-randomly in both main and reference arrays while maintaining the same lateral spatial relationship between the main and reference array element pair excited at any time. The reference array comprises a larger number of elements than the horizontal elements in said array and the adjacent group of reference elements excited during any scan cycle of the main array is shifted laterally for each succeeding main array scan cycle.

Abstract: A sequential-lobing, radar, tracking device, particularly adapted to radars which scan mechanically in the azimuth plane and which have frequency-phase scan in addition. The phase scan operates to displace the beam in the vertical or elevation plane substantially normal to the plane of mechanical scan. Frequency scan provides a form of scan vernier and provides at least a substantial scan component in the direction of mechanical scan. The frequency scan is programmed to employ the time delay introduced between two vernier azimuth beam pair positions by the mechanical scan in azimuth, so that azimuth measurements, i.e., as between beams which tend to bracket a target, are made at the same transmitted frequencies. The azimuth measurement is therefore independent of frequency scintillation effects resulting from the unpredictable variation of radar target cross-section as a function of frequency.

Abstract: An electro-plating method and apparatus therefor in which a discrete area of plating, such as a stripe about an elongated workpiece can be deposited without the use of separate masking. A plating solution having a depth equal to the length of the stripe desired is floated over a denser, inert, immiscible liquid (such as a liquid fluorocarbon). Workpieces are attached to a carrier which is electrically energized as cathodes and which are positioned vertically such that the area to receive the plated stripe is within the layer of plating solution, the workpieces projecting above the plating solution layer and below into the inert liquid as necessary. Pump weir and sump arrangements provide for maintenance of the plating solution and inert liquid levels and an anode is separately provided.

Abstract: A radio navigational device for determining the angle of a mobile craft by analyzing the signals arriving at each element of a linear array of n equally spaced elements. A series of received R.F. pulses emanating from the mobile craft by transmission or reflection provide contemporaneous signals at the antenna elements with a phase difference .psi. between successive elements in accordance with the angle of arrival of the R.F. pulses. Using "zero" IF techniques, each signal of the series is processed to provide signal outputs in I and Q form. Sequential or parallel sampling of these I and Q signals provides a synthesized scanning beam signal from which .psi. is determined.

Abstract: A device for coupling a signal value out of a circuit which itself is floating at some relatively high voltage (termed common-mode voltage). A sensor for converting the parameter to be measured to a signal voltage, together with an amplifier and light-emitting diode are powered by a floating power supply of minimal power rating at the location of the common-mode voltage. An optical fiber link, which itself has great electrical insulation characteristics, joins the LED with a solid state light-to-electric transducer at a relatively remote location. Circuit means responsive to the light-to-electric transducer are included for outputting an analog value representative of the quantity to be measured at the point of the common-mode voltage. This LED, fiber optic link and light-to-electric transducer constitute a first OCI (optically coupled isolator).

Abstract: A system for providing the plural variable phase RF signals required to control the beam pointing angle of a phased array. A light energy source (shown as a laser generator) is modulated by an RF signal and fed to a plurality of channels in parallel. Each of the said channels corresponds to one radiating element of the phased array and each channel includes as many selectively employed fiber optic delay lines of different lengths as are required to generate the discrete phases required at the corresponding antenna (radiator) element of the array. A commutating programmer controls the selection of individual radiating element phases for each successive beam pointing position.

Abstract: A hermetically sealed relay of the reed-type in which an elongated switching control rod is angularly displaced in operation. The extreme positions include internal stops, which may be contacts, in which case the switch is a single-pole-throw device. An attached actuator for the switch device provides tolerance-absorbing overtravel by means of uniquely arranged resilient means, such that switch-gap tolerances are effectively absorbed. The device may be of the magnetically latching type or may, in simplest form, include a single controlling electromagnet and only one fixed contact.

Abstract: A modified maximal length PRC (pseudo-random code) sequence generator for use in autocorrelating systems such as CW, bi-phase modulated PRC radar systems. The code generator for the system is a modified version of a known shift register and feedback arrangement, which provides a wordlength of 2.sup.n - 1 as known in the prior art. Means are shown for adding a zero in the sequence of n-1 zeroes which always occur within the PRC word according to pseudo-noise theory. The result is an autocorrelation function having no residual value for several bits on either side of the correlation peak, thereby providing a theoretically infinite range discrimination in the near vicinity of a true range value.

Abstract: A system for providing secure communication by use of optical frequency transmission between an aircraft or spacecraft and a deeply submerged submarine. The submarine extends at least one fiber optic cable terminated in a lens arrangement. A flotation unit insures that the cable is extended substantially vertically to a point approaching, but not penetrating the surface of the sea. The thickness of the water layer between the surface and the cable upper end is thereby such as to reduce the attenuation of transmitted and received optical signals. Submarine communications may thereby be effected through modulated light beams while the submarine itself remains at a greater and more secure depth.

Abstract: The novel reversible shaded-pole motor has a stator lamination which is symmetrical about the horizontal and vertical magnetic axes. The lamination shape corresponds to two E's placed against each other. In the center, it has a circular hole for receiving the squirrel-cage rotor. Yoke parts are placed on the open sides of the E and four like coils traversed by the yoke parts are inserted in the windows obtained at the corners of the stator lamination. Shading rings are slipped over the central short legs of the E's. For the operation of the motor in each direction of rotation, two diagonally opposed, series-connected coils are connected directly to the single-phase mains, while the other two are connected to the single-phase mains via a resistor.

Abstract: A Doppler Navigation Beacon incorporating the moving reference concept in a planar antenna matrix with programmed excitation, replacing the linear commutated array of the prior art to provide vertical diversity for azimuth guidance use and horizontal diversity for vertical guidance use. A pencil-beam effect is obtained without change of signal format or receiving station processing. Technique applicable to Doppler type navigation (landing) systems and to direction finding generally.

Abstract: A ground station for VOR navigation systems with at least one transmitter and several radiators, which ground station radiates azimuth-dependent and azimuth-independent information. The azimuth-dependent information consists of the wave amplitude-modulated with 30 Hz in the field and generated by the superposition of the nondirectionally radiated VHF carrier on a VHF figure-8 directional pattern rotating at 30 Hz. The azimuth-independent reference wave consists of a 30-Hz wave which is contained as frequency modulated in a 9,960-Hz subcarrier wave amplitude-modulated on the VHF carrier.

Abstract: A multimode loop antenna arrangement for generating various radiation/reception patterns, the loop comprises a plurality of peripheral gaps which are fed through hybrid networks or the like for the production of specialized patterns, such as cardioid, mutually orthogonal dipole modes, and combination modes, such as the so-called turnstile configuration. The antenna is basically non-resonant unless separately tuned and is most useful where broadband operation and minimal size and weight are important.

Abstract: An ILS (Instrument Landing System) having at least one of the Glide-slope and Localizer functions, each of said functions comprising course and clearance signals. For the course and clearance signals of either function, a single transmitter is supplied, the necessary frequency difference between those signals being obtained by dividing the transmitter output into two signals, one of which is uniquely phase modulated to produce a predetermined frequency offset with respect to the other.

Abstract: A scanning radio-frequency direction finder which includes two synchronously scanned beams (antenna patterns) having their boresite (symmetry) axes angularly offset by a predetermined amount, either physically or by control of time of operation. A first of the beams is double-lobed with a null at its boresite while the second has its maximum at its boresite. The signals received through each pattern are continuously phase measured and the phase of signals through the second beam is stored when the received signal strength therethrough reaches a predetermined value. The continuously measured first beam signal phase is compared with the aforementioned stored second beam signal phase, the instantaneous scan angle of the first beam at the time of phase equality being taken as the correct angle of the target reflector or source of received signals (target). The result is much improved angle measurements, especially in elevation at low angles.

Abstract: A ball and cone type variable ratio mechanical transmission in which the cone angles are chosen to provide optimum efficiency, increased power handling capability and extended service life.