Abstract: A passive direction finding system incorporating at least one set of spacapart antennas, the incoming signal at one antenna being coupled through a delay line having a multiplicity of taps thereon, a plurality of channels equal in number to the number of delay taps and signal processing means coupled to the output of said channels, a reference channel coupled to the output of the other antenna, phase shifting means for varying the phase of the reference channel signal, a frequency modulated oscillator which provides an output signal that is beat against the outputs of the delay line and the output of the second antenna, and a correlator coupled to the output of the channels for determining when correlation exists between a signal from the first antenna and the second antenna to indicate direction of an incoming signal with respect to the baseline between the set of antennas.

Abstract: A system for controlling the emission of a device having a sense electrode for sensing a measure of an emission species from a source within the device. The sensed measure of the emission species is converted to a control signal. The output of the source is modified in response to the control signal by varying the time during which the source emits the emission species.

Abstract: To measure the contents of a bunker or silo a transmitter mounted over the bunker beams down on to the contents surface a very high frequency signal that is caused repeatedly to rise and fall in frequency with either a constant sweep time and a progressively varying amplitude of frequency change or a constant amplitude and a progressively varying sweep time. The reflected target return signals are mixed with the transmitted signal to obtain a beat frequency which is filtered and processed to derive a signal representative of the range of the target, i.e. the contents surface, below the transmitter. To discriminate against target returns from fixed parts of the bunker structure, such as support members, a control unit is provided with a memory store into which are preloaded signals representative of fixed structure returns. The target returns received when the apparatus is in operation are then compared with the stored signals and any that are the same as stored signals are rejected.

Abstract: A linearity inductance and a side pincushion correction inductance are wound on outer leg core portions of a single E-core. A magnet biases the linearity inductance core portion for saturating that portion each horizontal deflection cycle for producing a linearity corrected horizontal deflection current. A high reluctance path for flux mutually linking both the linearity and side pincushion correction windings is provided by the E-core configuration. The portion of the flux generated by the side pincushion correction winding that does flow in the linearity winding core portion compensates for undesirable vertical rate changes in the magnetic bias of the linearity winding core portion.

Abstract: Disturbing components of the Doppler frequency spectrum in a radar receiver, having coherent integration, are suppressed. In this technique, the order of interference suppression and coherent integration is changed such that the echo values are first fed to a circuit to effect a Fourier transformation. Then, the disturbing components in the frequency band are deliberately suppressed, and a sub-optimal detection method suitable for real-time operation is derived from the optimum detection model in that sub-matrices symmetrical with the principle diagonal are formed from the power spectrum matrix, through which approximate decorrelation of the disturbing components is achieved.

Abstract: A receiver of a pulse-type radar has a main i-f channel feeding a fixed-echo suppressor of limited dynamic range and, in parallel therewith, an ancillary channel of extended dynamic range including a logarithmic amplifier and a processor. The latter averages the amplitude of incoming echo signals over a range-and-azimuth cell and then over one or more antenna revolutions. The resulting mean value of the signal amplitude is used to control the gain of a linear amplifier in the main channel so as to adapt the dynamic range of the echo signals to that which can be handled by the fixed-echo suppressor.

Abstract: A doppler range detector with early and late range gates responding to radar returns or either side of maximum velocity range and supplying a peak output amplitude when the early and late gates have the same doppler frequency. A peak detector is used to detect slant range with a dual pulse ranging system. The returns are supplied to two zero beat mixers, the output signals of which are passed through separate bandpass filters to a multiplier. The multiplier output is supplied through a low pass filter to the peak detector.

Abstract: To provide static convergence correction motion to the outer beam of three in-line electron beams of a color cathode ray tube, a magnetized sphere is located adjacent each outer beam. Each sphere is magnetized across a diameter to produce, for example, a two-pole magnetic field for providing the correction motion. The two-poles are separated along a polar axis. Each sphere is located in a housing which permits rotation of the polar axis of the sphere into alignment with the longitudinal axis of the cathode ray tube and permits rotation of the polar axis out of longitudinal alignment in both horizontal and vertical planes.

Abstract: 1. An FM doppler fuze system comprising means forcombining a periodic wave ith white noise, white noise being a random mixture of frequencies possessing a constant power spectral density, means for modulating a carrier frequency with said periodic wave plus noise and transmitting a signal in the direction of a target, means for mixing a portion of said transmitted signal and a return echo signal from a target, and means for passing the band of expected doppler frequencies from the output of said mixer to provide an output operable to actuate the detonation circuit of a fuze.

Abstract: An improved signal processing technique for providing rapid evaluation of rget echoes on a pulse by pulse basis. An analyzing circuit is constructed to receive pulse echoes from a signal transmitting system and convert the pulses to provide amplitude data through a pulse height to pulse width converter. When used in a radar system, each echo pulse is converted to a fixed amplitude pulse with a pulse width proportional to the echo amplitude as the antenna sweeps by the target. The pulses are thereafter transmitted to a display device in place of the normal radar video. The resultant display provides a real time two-dimensional amplitude pattern which enhances target detectability in the presence of noise and in multiple target environments.

Abstract: In a radar which transmits a phase-coded train of sub-pulses and which derives the in-phase (I) and quadrature (Q) components of the received echo signals with respect to a local reference oscillator is embodied a phase discrimination constant false alarm rate (CFAR) system partially comprising a phase angle sensor for measuring the phase angle of the echo signal as one of at least eight predetermined phase angle representations, which are characterized preferably by binary numbers in Gray format, based on the relative magnitudes and polarities of the I and Q components of the echo signal. The phase angle representations may correspond exclusively to phase angle increments in the phase angle interval of 0.degree. to 360.degree. with respect to the local reference oscillator. Preferably, the phase angle increments are evenly partitioned within the 360.degree. interval.

Abstract: An early-late gate for a high resolution range tracking system of a radar ing a high frequency double-balanced mixer in conjunction with a bi-polar pulse gate allows simplified early-late gating for a range error measuring system.

Abstract: An airborne system for automatically and electronically recognizing and dcting the relative presence of invariant features of a transient submarine signal occurring in the presence of signal-like noise. A plurality of comb filters receive MAD signal information in the amplitude-time domain and filter it to provide amplitude-time-frequency domain information. The primary features (positive and negative slopes) of this latter information are then abstracted, the abstracted information being utilized in a signal processor to detect and recognize the relative presence of invariant, submarine recognition features. Upon recognition, a decision thereof is routed to a visual display.

Abstract: A discriminator circuit having utility in proximity fuze firing circuits is apable of distinguishing between spurious and proper signals on the basis of both amplitude and rate of amplitude rise. A firing switch, operated by a slow-charging trigger circuit, and a lock out switch, operated by a fast-charging trigger circuit, are both triggered by the same signal. If the rate of input signal envelope rise is faster than that for a proper firing signal, the lock out switch fires and inhibits triggering of the firing switch. The trigger circuits are biased to permit the firing switch to be triggered before the lock out switch when the input signal rate of rise is slow enough to be followed by the slow-charging trigger circuit. For signal rates of rise which are slower than that associated with a proper signal, a capacitor in the slow-charging trigger circuit becomes charged to block triggering of the firing switch.

Abstract: A picture display device comprising an electron source for producing band-shaped electron beams, electron beam control means for controlling the selective passage of the electron beams, deflection means for horizontally and vertically deflecting the electron beams and display means for emitting light in response to impingement of the electron beams thereon. The electron source comprises a plurality of linear thermionic cathodes, a focusing electrode for focusing the electron beams emitted from each linear thermionic cathode to band-shaped electron beams and an electron beam emitting electrode having a plurality of apertures therethrough, and a negative pulse voltage is sequentially applied to the linear thermionic cathodes to emit the required electron beams for one scanning line.

Abstract: 1. A radar signal code generator comprising:a. first oscillator means comprising an output terminal for producing, at id terminal, a continuous signusoidal wave having a continuously varying frequency; andb. pulse generator means operatively connected to said first oscillator means output terminal for producing a plurality of pulses, each of which consists of a constant frequency carrier wave, the initiation of each of said pulses occurring at a predetermined time interval after a respective cycle of said sinusoidal wave from said first oscillator means reaches a selected phase value.

Abstract: The trace switch of a horizontal deflection circuit is coupled to a secondary winding of a flyback transformer. The primary winding is coupled to a source of energy and a regulator switch. A control circuit varies the phase angle of the regulator switch in accordance with an energy level of the deflection circuit. A regulator commutating inductance in combination with a commutating and tuning capacitance controls the duration of conduction of the regulator switch. The capacitance independently tunes with a flyback transformer winding to transfer energy from the source in a resonant manner.

Abstract: A side pincushion distortion correction circuit has an impedance circuit connected in series with the deflection coil in a television receiver. A controllable switch connected in parallel with the impedance circuit is operated by a switching signal, the phase of which is modulated by a combination of a parabolic signal at the vertical rate and a control signal corresponding to the brightness of a reproduced picture on the screen of the television receiver in order to maintain proper correction of side pincushion distortion despite variations in the brightness of a picture reproduced on the cathode ray tube of the television receiver.

Abstract: A waveform comparison and display system using a cathode ray tube, which is provided with a digital memory function for sequentially storing input signal levels in digital quantities and re-reading them out under control of desired clock pulses and with a display function for displaying on the cathode ray tube two waveforms obtained in outputs produced by high-speed switching of the input signal and an analog signal re-read out. The storing operation and the sweep operation of the cathode ray tube are controlled by a trigger signal synchronized with the input signal. The generation of the clock pulses is start-stop controlled in synchronism with the sweep. Accordingly, the two waveforms are displayed on the screen of the cathode ray tube in such a manner that they are stationary with respect to each other.

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.