Abstract: A target extractor for radar systems which accurately determines the radial position of the target within the range cell containing the target. The azimuth of the target is determined by conventional extractor systems. An incremental target range is located with respect to a primary range cell boundary. The primary range cell is selected as the range cell which contains the maximum number of reflected transmitter pulses. The number of reflected transmitter pulses received in secondary range cells located radially below and radially above the primary range cell is determined by the target extractor. The target extractor also determines the ratio of the pulses detected in the secondary range cells which are located radially on each side of the primary range cell. The location of the target defined within the radial dimension of the primary range cell is determined by interpolation circuitry in the target extractor.

Abstract: An MNOS non-volatile memory circuit, which inhibits the application of a write voltage to a memory cell at times when the write data is the same as the data stored in such cell to prevent saturation of the transistor, includes provision for applying automatically such a write voltage upon the detection of a predetermined weak storage condition in such cell.

Abstract: A radar system of the type utilizing an optimal estimator to process raw range and angle track data for driving a radar antenna, where the tracking computations, range rate, and angular rate of the range vector are utilized in estimating the target velocity vector and the target acceleration vector. The attenuation inherent in the practical estimation of target acceleration is effectively removed for severely maneuvering targets by a compensating system that provides an attenuation factor, and multiplies the estimated acceleration output signal by the reciprocal of such factor. The implement control system is governed by the estimated target position and estimated target velocity from the estimator, and the modified acceleration signal of the compensating system.

Abstract: A circuit utilizing a source follower and a comparator to interface an MOS digital circuit with bipolar digital circuits is disclosed.

Abstract: An acoustic surface wave signal transmission device includes a medium having a surface suitable for propagating acoustic energy or waves and having a first impedance characteristic. The surface of the medium includes an array of periodic discontinuities of a second impedance characteristic. The widths of the discontinuities vary in a predetermined manner to reflect a portion of said acoustic energy in proportion to the widths of the discontinuities. A transmitting transducer on said surface converts an input electrical signal into corresponding acoustic energy or waves and launches the energy or waves on said medium toward said array of discontinuities. The acoustic energy is reflected from said array of discontinuities toward a receiving transducer which converts the reflected acoustic energy or waves into a corresponding electrical signal.

Abstract: A system for detecting threats with respect to stored beams that have been established as characteristic of the beams of the signal emitters associated with a particular threat, and for adaptively redefining the stored beam parameters of signal emitters associated with a particular threat in response to the parameters of beams detected by the adaptive tracking system. A radar system for tracking a signal wherein the radar system periodically verifies that tracking has not been transferred from the original signal to a second signal having similar parameters.

Abstract: A low PRF pulse doppler radar system utilizing a VIP digital filter bank signal processor to suppress echoes from terrain, rain, and chaff, and pass echoes from aircraft moving at higher speeds is disclosed.Each of a plurality of VIP filters individually provides high attenuation to undesired signals over designated frequency bands, the width of which are a large fraction of 1/T.sub.av where T.sub.av is the average interpulse period. Little or no attenuation of desired signals having doppler frequencies greater than 1/T.sub.av occurs. The outputs of the plurality of filters are desensitized to prevent false alarm from clutter, and the presence of a desired radar pulse echo is determined by a comparison with a threshold level.

Abstract: A synthetic aperture radar in which radial motion compensation is provided by a monopulse null tracking loop which tracks the null position of a stabilized monopulse antenna, and in which tangential motion compensation is provided by a tangential velocity measurement loop which tracks the cross-over angle of the monopulse antenna pattern. Since the motion compensation for the synthetic aperture radar is made in relation to a stabilized monopulse antenna, the imaging process for the synthetic aperture radar may be controlled in response to the angular scan rate of the antenna.

Abstract: A system for multiplying a first multibit digital number by a second multibit digital number to produce a multibit product is disclosed. The system utilizes a plurality of identically programmed digital memories. The memories are selectively interconnected to form a plurality of arrays. The memory comprising the first array receives as an address input the two least significant bits of each of first and second digital numbers to be multiplied and produces as an output the two least significant bits of the product and the carry signals to the next array. The memories comprising the second and subsequent arrays receive as address inputs bits of the first and second digital numbers and the carry signals from the preceding array and produce as an output two additional bits of the product and carry signals to the next array. This process is repeated to produce a product having twice as many bits as the multibit input signals.

Abstract: A phase distortion detector is used in a wideband feedback control loop to detect phase distortion on a wideband pulsed linearly frequency modulated waveform (chirped) without the use of excessively long delay lines. The detector mixes two reference signals, each of a predetermined frequency, one frequency higher than the other. A phase lock loop ensures that the two signals are phase coherent. Each signal is then mixed with the chirped waveform, delayed for different time intervals, and mixed again to produce an error signal proportional to the phase distortion on the chirp pulse which distortion is also an indication of the frequency non-linearity of the chirp pulse. The error signal is then used to correct such non-linearity.

Abstract: A system for protecting a turbine-generator power plant governed by signals representative of turbine mechanical power and generator electrical power to reduce at times the turbine mechanical power, with an electronic filter included therein for the purposes of filtering a periodic time varying component of the electrical power signal having a response time within adequate protective limits, is disclosed. More specifically, the electronic filter generates a train of fixed time durations wherein during each fixed time duration the maximum and minimum amplitudes of the electrical power signal are selected. A signal is sampled at the end of each fixed time duration and held constant for each next fixed time duration, said signal being representative of the average of the maximum and minimum amplitudes selected during each fixed time duration.

Abstract: A stabilized charge injector for charge coupled devices (CCD) includes a diffusion and two or more gate structures in a CCD channel wherein the diffusion alternately acts as a source and drain of the minority-type signal carriers. D.C. signals are applied to the gates immediately adjacent the diffusion and the next successive adjacent gate to provide a charge injection which is proportional to the difference between the signal voltage applied to the one of the two gates and a DC reference voltage applied to the other thereof. Low noise performance is achieved through utilization of a quasi-static operation in which neither of the aforementioned gates adjacent the diffusion is pulsed. Moreover, the use of a gate injector presents at the input, a true capacitance defined as a function of the gate oxide layer. Hence, the value of capacitance is constant and independent of the signal voltage applied.

Abstract: An addressable MNOS transistor structure is disclosed employing a plurality of gate regions between the source and drain diffusion regions of each transistor cell. The transistor cell is characterized by high and low threshold states which are settable by selective actuation of the corresponding plurality of gate regions. Reading of the state of the transistor is accomplished by applying a read voltage, having a value intermediate the two threshold values, to the corresponding plurality of gate regions and measuring whether or not an applied charge discharges from one diffusion region to the other.

Abstract: A charge coupled device (CCD) circuit suitable for low level input signals, e.g., from a photodiode, is disclosed. A low noise bias current source directly injects a current into a metal-oxide-semiconductor (MOS) device in order to increase the transconductance of the CCD, consequently extending the bandwidth of the CCD without increasing output noise levels.

Abstract: A complementary MOS voltage level shift circuit which can be used as a memory buffer circuit, for example, is disclosed. The circuit utilizes both N-channel depletion mode devices and P-channel enhancement mode MOS devices preferably fabricated on silicon-on-sapphire. Both types of devices are operated with only negative or zero gate-source voltage in order to minimize threshold voltage shifts in radiation environments. A capacitive voltage level shifting technique is used to obtain push-pull operation with driver type devices in order to reduce power consumption and increase switching speed while feeding into a capacitive load. Load type devices are used to prevent discharge of a capacitive load.

Abstract: A target seeker circuit contained in a projectile having a trajectory guidance mechanism cross-correlates returns of a cross-polarized antenna pattern to distinguish between target returns reflected by man-made targets and clutter returns reflected by naturally occurring articles to cause the trajectory guidance mechanism to direct the projectile towards the target. One coordinate of diversity in the cross-polarized returns is achieved by changing the RF frequency of the antenna pattern while a second coordinate of diversity is achieved by changing the aspect range of the clutter. The target returns are distinguished from the clutter returns either by comparison to a threshold value which is set in relation to the worst case clutter level or, alternatively, by comparison to an adaptive threshold which is responsive to the dynamic clutter level.

Abstract: A field effect pentode transistor, which provides a gain over an extremely broad band of frequencies is disclosed. The transistor has source and drain electrodes defined by ohmic contacts, a first gate input control electrode defined by a Schottky-barrier, a screen electrode, and a second control gate Schottky-barrier electrode. The screen electrode is an ohmic contact located between the first and second gate control electrodes; and the second control electrode is located between the screen electrode and the drain electrode.

Abstract: In a radar system such as Doppler radar, clutter is eliminated without a requirement for somewhat sensitive frequency spectrum positioning. Processed returns are integrated over different halflook periods, where a look period is a period of constant pulse repetition frequency, and multiplexed into a postprocessor. The postprocessor measures the presence of clutter, and provides a blanking signal for clutter returns during portions of an operating cycle corresponding to clutter peaks.

Abstract: A solid state control panel system utilizing optical coupling between a graphic control panel and a hand-held probe is disclosed. Separate light emitting control diodes and display diodes are utilized on the graphic panel. In response to a coded optical coupling between selected light emitting diodes on the panel and a light sensitive diode in the probe, various switching functions are performed. The system provides three different types of coding for each complete switching operation, namely, time coding, polarity, and pulse sequence coding. The probe includes means to inform the operator when proper optical coupling occurs; and is so constructed mechanically that it can be operated by pressure engagement with the panel, or as a gun. The system is structured to provide various types of switching functions, including the provision for selecting any one of a plurality of individual switches in its present state for display and control with each selected switch having a multiplicity of states.

Abstract: A method and apparatus for charge addressing a non-volatile MNOS memory cell in a LSI array of memory cells, is disclosed. Each MNOS cell of the array is made up of a substrate; adjacent diffusion areas in the substrate; a memory window intermediate the adjacent diffusion areas, controlled by a memory gate; and an enable gate adjacent the memory window and overlapping one of the diffusion areas. The memory gate and the enable gate are each separated from the substrate and each other by silicon dioxide/silicon nitride layers to provide a capacitive dielectric. Addressing of an individual cell in the array is achieved by selective activation of a corresponding enable gate and a corresponding memory gate, which are formed in an orthogonal grid array. The cell is accessed by a single stage of a shift register for both read and write operations through a transfer gating means.