Abstract: A data switch which can rapidly configure and reconfigure multiple channels between computer equipments for digital data transmitted at a rate in excess of 10 megabits per second. The switch includes a switch matrix connected between an input and an output voltage level buffer, a mini computer, and control circuitry. The switch matrix comprises three stages, each containing 256 switching elements which are active integrated circuit elements each having 16 data inputs and one data output. A channel is configured through the switch matrix when one switching element in each stage responds to a control signal to couple one of its data inputs to its data output, over a million different channel configurations being possible. Each switching element is heavily grounded to effectively eliminate cross talk between channels and each data input line of each switching element is provided with an amplifier to improve time fidelity of the switch.

Abstract: An apparatus for estimating the mean level of a stochastic process such as ould be observed at the output of a radar, communications, or sonar receiver and for using the mean level to provide a threshold with which possible signal samples are compared to determine the presence or absence of the signal. The estimated mean level is used in lieu of a priori information when it is unreasonable to assume that the characteristics of the stochastic process are known. A first order recursive filter receives signal samples and provides an output which is proportional to the mean of the stochastic process. The output of the first order recursive filter Y.sub.n is multiplied by the factor T such that the product TY.sub.n is a threshold quantity which is compared with the input signal samples X.sub.n. When X.sub.n exceeds TY.sub.n an output is indicated.

Abstract: A single antenna array having a phase shifter at the input of each antenna lement and fed by a multifrequency input for simultaneously generating at least two beams. When the different excitation frequencies are simultaneously inputted into the phase shifters, a separate phase increment is introduced into each radiator for each frequency. The result is a separate beam output from each frequency input, the beams being generated simultaneously but at different beam pointing angles.

Abstract: A switching system for rapidly configuring transmission paths between comer equipments for high speed digital information in parallel form couples the input of a parallel-to-serial (P/S) converter to the output of each equipment providing information and the output of a serial-to-parallel (S/P) converter to the input of each equipment receiving information. A digital switch rapidly configures information transmission channels between its inputs and outputs in response to instructions from a configuration control. Each switch input is coupled to the output of a P/S converter, and each switch output is coupled through a switch output lead to the input of an S/P converter. A clock provides a periodic clock signal to each P/S converter through an adjustable delay control and to each S/P converter through a clock lead, wherein the electrical lengths of the switch output lead and clock lead coupled to the same S/P converter are equal.

Abstract: An encoding system wherein digital information comprising data, clock, and artitioning components is coupled to an encoding means comprising interconnected digital elements to generate a serial encoded signal having the encoded data, clock, and partitioning components inherent in the structure of the encoded signal. The encoded signal may be stored in a magnetic record/reproduce system and subsequently coupled to a decoding means comprising interconnected digital elements to recover the data, clock, and partitioning components of the original digital information.

Abstract: A millimeter wave amplifier having broadband characteristics in which a G diode or other two terminal negative resistance device having an integral heat sink is center mounted in a reduced height waveguide. The heat sink is attached to a mechanism for selectively adjusting its penetration into the waveguide cavity. The introduction of the heat sink into the waveguide cavity creates a discontinuity to the propagation of energy which causes localized waveguide modes other than the dominant mode to exist. The adjustable position of the heat sink allows the reactance due to the introduction of these modes to be variable, proper adjustment resulting in the cancellation of the parasitic reactances inherent in the packaged negative resistance device.

Abstract: A video-blanker system for supplying blanking pulses to receivers including main delay one-shot for responding to a pretrigger pulse and establishing a time delay in response thereto by providing an output pulse of a predetermined width and an auxiliary delay one-shot having its input AND coupled to the pretrigger pulse and to the output of the main delay one-shot for responding to pretrigger pulses occurring during the timing cycle of the main delay one-shot. The outputs of the main and auxiliary delay one-shots are trailing edge discriminated and OR coupled to initiate a pulse width one-shot which supplies the required blanking pulse. The main and auxiliary delay one-shots include means for reducing the recovery times thereof, without affecting the quasistable periods.

Abstract: A microwave or other r.f. radiation detector in which a tunnel diode or other negative resistance device exhibiting the proper I-V (current-voltage) characteristics is biased in the positive resistance region near the voltage point at which the peak current occurs. Microwave or any other r.f. signal is picked up and detected by the tunnel diode such that an oscillation circuit connected thereto is caused to oscillate. The frequency of oscillation varies in accordance with the amplitude of the detected r.f. and is monitored with an earphone and/or a meter.

Abstract: A voltage level shifting driver and receiver for interfacing systems using ositive logic levels and systems using negative logic levels. The driver operates to convert positive voltage logic levels to negative voltage logic levels and the receiver operates to convert negative voltage logic levels back to positive voltage logic levels.

Abstract: An antenna system utilizing the multibeam advantages of the Butler matrix achieve beam steering with the additional capability of placing nulls in the direction of undesired radiation. The system comprises essentially a Butler matrix with an adaptive circuit interposed between each of the antenna elements and a corresponding one of the hybrid matrices of the Butler matrix. Switch means are also provided for separating the transmit and receive functions.

Abstract: A broadband millimeter wave (26.5-40 GHz) mixer/converter utilizing slotl and coplanar strip-line for the construction of the hybrid junction. The RF and local oscillator signals are applied 180.degree. out of phase to a pair of beam-lead diodes. A diplexer consisting of a low-pass filter and a bandpass filter is also provided to separate the IF and LO signals. A first microwave integrated circuit (MIC) card carries the waveguide to slotline transition, the slotline transmission section, the tapered coplanar waveguide section and the LO bandpass filter. A pair of Schottky-barrier diodes are connected across the transmission channels of the coplanar waveguide section to form the hybrid junction. The LO input is applied to a section of suspended strip-line on this first MIC card. A second MIC card carries the IF low-pass filter and couples to the IF output of the mixer.

Abstract: A device for implementing the arithmetic operations of addition and multication utilizing CCD concepts and MOSFET properties. First and second CCD channels convert first and second input voltages into first and second charge quantities, respectively. The first and second charge quantities are added in a third CCD channel to provide a third charge quantity linearly proportional to the sum of the first and second input voltages. The three charge quantities are sensed by three floating gate amplifiers operated in the saturation region. The outputs of the floating gate amplifiers are subsequently combined by a differential amplifier, the output of which is linearly proportional to the product of the first and second input voltages.

Abstract: An improved antenna feed providing control of the plane of polarization ecially useful with "scanning with compensation" radar tracking. An input transducer is coupled to first and second output transducers whereby the output transducers transmit two pencil-beam radiation patterns which are squinted by equal but opposite angles with respect to the scan axis. During reception, however, a non-reciprocal coupling means provides for separate sensing of the return signals rceived by the first and second output means and converts the signal received by the second output means so that it is in quadrature relationship with the signal received by the first output means.

Abstract: A microstrip hybrid directional coupler in which the 180.degree. phase sh is effectuated by a twisted pair of parallel conductors.

Abstract: A wholly digital system for computing the discrete Fourier transform of sequentially received data in a recursive fashion. Two parallel shift registers store and shift the real and imaginary components of the complex number X.sub.k + iY.sub.k. The data in the parallel registers are successively shifted one bit per strobe in response to receipt of new data. Additional logic operates recursively on successive data inputs to compute the discrete Fourier transform.

Abstract: A mode-launcher, waveguide antenna element providing signal transition from principal coaxial TEM-mode to a dominant TE.sub.01 -mode of a rectangular waveguide. A triangular element integrally formed with the waveguide structure and whose plane is normal to the magnetic field of the waveguide is disposed intermediate the frontwall radiating slot of the waveguide and the waveguide backwall through which the coaxial connector probe is introduced.

Abstract: A serial-to-parallel data conversion and synchronization scheme in which a lurality of active logic elements are utilized as delay lines. Each of the delay lines introduces a delay equal to the period of one data bit and one additional delay line introduces a delay equal to one half the period of a data bit. The input of the first delay line is connected to the data input of a first flip-flop and the outputs of each of the plurality of delay lines are each connected to the data input of a flip-flop. The output of the additional delay line is connected to the clock inputs of each of the flip-flops whereby the serial data word is converted to a parallel data word and the conversion is internally clocked by the delay lines themselves.

Abstract: A system for measurement of teletype or other communication channel quality herein the bit signal element duration is divided into m subintervals. A plurality of transition counters are provided such that each transition counter counts the number of DC transitions occurring during a different set of said subintervals. The counts are then summed for a predetermined plurality of bits. The monitoring device of the present invention is then calibrated by comparing the sums from each of the plurality of transition counters with a known error reference. The most accurate transition counter is thereby determined and is subsequently used for on-line distortion monitoring.

Abstract: A system for communicating digital data which utilizes a synchronization eme in which a transmitter transmits a binary 1 followed by n data bits which are followed by n + 1 binary 0's and in which a receiver is synchronized with the transmitter by generation of a master clock in response to receipt of the transmitted binary 1 and by initiation of a frame pulse having a pulse duration equal to the duration of the incoming data frame.

Abstract: A transition apparatus for changing from a waveguide to a coaxial connect A tapered or stepped ridge waveguide section is electrically connected to a section of microstrip which is electrically connected to a coaxial connector, the coaxial connector being in line with the waveguide.