Abstract: The invention is a novel noise reference generator for use in amplitude comparison radiometric systems for the purpose of rapid precision control of the over-all gain of the radiometer receiver. The reference generator operates by cyclic modulation of the temperature of a unique planar thin film microresistor which may be disposed in a constant temperature environment. A strip transmission circuit provides a common path for the microresistor heater currrent and for the generated noise signals, along with means for separating these currents.

Abstract: An encoder/decoder is provided having two random bit generators which are cross-coupled in the Encoding mode with the data signal being directed to the input of each random bit generator. The data signal is also logically combined with the output of each random bit generator. In the Decoding mode the random bit generators are connected in a feedback configuration and the to-be-decoded signal is directed to the input of each random bit generator. The to-be-decoded signal is also logically combined with the output of each random bit generator to provide the decoded signal.

Abstract: A frequency memory system having a smart noise component is receptive of an RF burst signal of a given frequency and of relatively short duration for determining the frequency and storing a signal of amplitude indicative of the given frequency and for producing by means of a voltage controlled oscillator (VCO) a signal at the given frequency of relatively long duration. The stored signal and a signal for amplitude corresponding to the actual frequency produced by VCO are utilized to produce an error signal to correct any error in the frequency of the signal produced by the VCO relative to the given frequency. Since the VCO is not capable of immediately accurately tracking the input frequency, a smart noise generator produces a signal of random amplitude which is added to the error signal to cause the VCO to produce at least a frequency component of its output signal which is equal to that of the input RF burst signal.

Abstract: A random noise generator for providing useful random noise power without amplification includes an anode and cathode element, disposed within a glass housing, with the electrical breakdown occurring therebetween along the inner surface of the housing is capable of generating broad band white noise.

Abstract: 10. Apparatus for generating a complex wave comprising means for generating a plurality of different concurrent short period series of pulses, a plurality of electrical networks, means for applying a different one of said series of pulses to each of said electrical networks, means for deriving a plurality of differently delayed unmodulated pulse signals from each of said networks in response to said applied series of pulses, means for combining said derived signals from predetermined ones of said networks, and means for selecting in a predetermined manner said delayed signal components, and means for deriving from said selected signal components a complex wave having a period longer than either of said selected pulse periods, said complex wave having a substantially longer period than either of said short period pulse series.

Abstract: The disclosure is directed to an apparatus and method for generating noise having characteristics of repeatability and reproducibility. A pseudo-random bit generator is responsive to clock pulses for simultaneously generating, at each clock pulse, a plurality of parallel pseudo-random digital bits which are successive bits of a pseudo-random sequence. In particular each new plurality of parallel bits is a successive group from the same pseudo-random sequence, thereby insuring a maximum number of totally uncorrelated groups. The bits generated at each clock pulse are operated on to produce an output noise signal as a function of the plurality of pseudo-random parallel bits generated at that clock pulse. In an embodiment of the invention, the operation on the plurality of bits comprises summing the value of the bits to produce a noise signal, the noise signal exhibiting a substantially Gaussian distribution with time.

Abstract: The disclosure is directed to an improved apparatus and method for generating a specified statistical distribution. Digital bits having properties of randomness are produced. In response to a group of the digital bits, a signal is generated which approximates the specified statistical distribution. When a particular characteristic of a group of digital bits is sensed, the generated signal is modified so as to obtain a statistical distribution that more closely approaches the specified statistical distribution.

Abstract: Pseudo-random binary sequence generator using a closed loop shift register. According to the invention, the output of the register feeds a switchable inverter which sends out the pseudo-random sequence of the register, alternately inverted and non-inverted, the inverter being switched once per cycle of the register.

Abstract: In an electrosurgical device, a RF generator is pulse modulated during coagulating procedures. Pulse repetition rate is varied allowing the occasional interjection of relatively wide pulses of RF energy while still allowing sufficient cooling time to avoid cell volatilization. The result is efficient coagulation with minimal cutting.

Abstract: Apparatus and method for sampling analog signals during successive time periods, the sampling signals being essentially aperiodic. The interval between sampling pulses is selected pseudo-randomly. A circuit for producing essentially aperiodic sampling signals gates a periodic signal through a number of delay means, each having a delay time that is a small fraction of each period, the number of delay means being selected by pseudo-random signals. Periodicity of quantization errors is broken up, thereby reducing concomitant unwanted harmonics of the sampling frequency that are introduced when the sampling signals occur at equal time intervals.

Abstract: 1. A generator for producing random binary bits comprising in combination, eans for producing a random noise electrical signal, means coupled to the output of said signal producing means for converting said random noise electrical signal into a variable width square wave signal having polarities proportional to the polarities thereof at any given instant, means connected to the output of said converting means for producing a plurality of constant frequency pulses the number of which is proportional to the widths of those portions of the aforesaid variable width square wave signal having the same polarity, and means effectively connected to said pulse producing means for timely sampling said pulses in terms of binary bits.

Abstract: In a binary system, for example, the "0" and the "1" are rendered more equi-probable in the output pseudo-random sequences of a switch controlled in a pseudo-random way by feeding to the inputs of the switch input sequences which are two and two complementary, i.e. the sum of two simultaneous digits of two such sequences is always 1.

Abstract: 6. In a key pulse system for generating key pulses of definite length and highly irregular magnitude with intervening spaces, cyclically operating devices for generating groups of irregular sequences of pulses at a rate much higher than the rate of occurrence of said key pulses, each such group of pulses existing for the length of one of said spaces, and means to determine the magnitude of the next key pulse from the last pulse in the group of pulses occupying the preceding space.

Abstract: The present invention relates to a binary random noise generator for the stochastic coding of digital or analog information, comprising a comparator having two inputs, one of which receives a reference voltage and the other a random analog noise coming from a source of noise, said comparator supplying at its output a binary signal with random transitions, said generator comprising a clock and a logic system which, on the one hand, effect the sampling of the binary signal with random transitions in synchonism with the frequency of said clock and, on the other hand, ensure the strict equiprobality of the two logic states of said binary signal with random transitions, without increasing the radius of correlation. The invention is more particularly applied to the stochastic coding of information with a view to calculation or transmission, with equidistribution of binary variable.

Abstract: A wide band, stable, random noise source with a high and well-defined output power spectral density is provided which may be used for accurate calibration of Johnson Noise Power Thermometers (JNPT) and other applications requiring a stable, wide band, well-defined noise power spectral density. The noise source is based on the fact that the open-circuit thermal noise voltage of a feedback resistor, connecting the output to the input of a special inverting amplifier, is available at the amplifier output from an equivalent low output impedance caused by the feedback mechanism. The noise power spectral density level at the noise source output is equivalent to the density of the open-circuit thermal noise or a 100 ohm resistor at a temperature of approximately 64,000 Kelvins. The noise source has an output power spectral density that is flat to within 0.1% (0.0043 db) in the frequency range of from 1 KHz to 100 KHz which brackets typical passbands of the signal-processing channels of JNPT's.

Abstract: A reliable, repeatable and stable generator capable of producing noise with nown or given amplitude probability distributions up to 96 dB dynamic range, commonly found in atmospheric noise VLF/LF frequency bands. A continuous impulse noise amplitude probability distribution is digitally synthesized in a piece-wise fashion in 6 dB amplitude increments. These increments are linearly combined with a digitally generated Gaussian noise component for simulation of VLF and LF atmospheric noise.

Abstract: The present invention relates to a device for producing an analog noise from a point process, the distribution of said noise being predeterminable, said device comprising a source of noise, a first generator or random pulse generator, a second generator or motif or function generator, the output of the source of noise being connected to the input of the first generator, the output of the first generator being connected to the input of the second generator, and the output of the second generator constituting the output of the whole of said device. The invention is applicable to the coding and transmission of information.

Abstract: The code generator of the present invention uses digital memories to replace the linear feedback shift registers of the prior art. Each memory contains the time ordered bit sequence for each of the component codes which in general, make up the overall, longer code. Since the entire bit sequences of the component codes are immediately available in the memories by appropriate addressing, the code generator can be initialized to an arbitrary, but defined code state within the response time of the memory element. As an additional benefit, at the option of the designer, the digital memory can be chosen to extract code segments, for example, 8 bits wide rather than single bits, and this parallel approach reduces code clocking speed through much of the code generator hardware, and/or may permit several code patterns for multichannel applications to be constructed using the same common memories.

Abstract: The specification discloses a random digital code generator operable over a series of key cycles for generating a randomized digital bit during each key cycle. The generator includes a plurality of first registers each having a predetermined cycle period which does not have a common factor with the cycle period of any other of the first registers. Circuitry is provided to step each of the first registers a predetermined number of steps per key cycle. A plurality of second registers are provided, along with circuitry for generating different numbers of clocking signals per key cycle for each of the second registers. Circuitry generates control pulses in response to the clocking signals and further in response to digital bits derived from selected taps on the first registers. The control pulses randomly control the number of times each of the second registers is stepped during each key cycle.

Abstract: An electronic countermeasures sequencer having a variable period clock, a ift register, a control switch for selecting manual or automatic mode, a ones detector, a zeros detector, and an interface driver.

Abstract: A random state generator to determine a random non-return to zero (NRZ) vage level at a particular clocked time with a noise generating diode or gas tube to provide a randomly fluctuating analogue voltage. The random voltages are amplified and applied to a transformer which acts as a gate for the random voltage. The secondary of the transformer has unidirectional conducting means connected to each of the ends and so poled that by applying a positive voltage pulse to a center tap on the secondary, the unidirectional current devices are forward biased and close the gate. The output of the transformer is connected to a bistable multivibrator which is thereby slaved to the random voltage polarity applied to its input during clock time.

Abstract: An improved noise loading arrangement and method are disclosed capable of measuring low intensity intermodulation distortion products, such as introduced in the operation of individual wideband transmission repeaters. The improved arrangement and method also have the further capability of resolving individual orders of distortion products. The arrangement utilizes a noise signal generator that produces a pseudorandom signal made of several spectral components providing high spectral density throughout a large bandwidth to simulate a broadband message load obtained by frequency multiplexing several independent signal sources. The noise signal is shifted in frequency before a quiet band is produced in the signal applied to the transmission apparatus to be tested. The orders of intermodulation distortion products appearing in the quiet band of the output signal of the transmission apparatus are individually measured to evaluate same.

Abstract: An arrangement for ciphering and deciphering comprises a number of cycle length counters. Each of the counters has a different cycle length and generates a series of bits by scanning associated memory fields containing internal-key-information. The series of bits are combined in a logical unit in order to obtain a ciphered series. The arrangement includes a plurality of memories each comprising a number of memory fields corresponding to the number of counters. Switches are arranged to select internal-key-information by selecting memory fields from different memories depending on a control device, which is operated by certain character combinations in the transmitted text on the sender side and on the receiver side of the system.

Abstract: A noise generator that is responsive to digital noise quality and noise modulation input signals to provide a controller noise signal to a voltage controlled oscillator. The noise generator adds a center frequency input signal, a weighted random noise signal, and a weighted wobbulated waveform signal to obtain a controlled digital noise signal and converts this noise signal from digital form to analog form to provide a noise generator output signal that controls the voltage controlled oscillator. The center frequency and modulation of the noise generator output signal spectrum are determined by the center frequency and weighted wobbulated waveform signals, respectively, and the range of the output signal spectrum is determined by the weighting of the random noise signal. A ramp input signal, which is converted from digital to analog form, is integrated and added to the noise generator output signal to further define the quality and range of the output signal spectrum.

Abstract: There is disclosed a masking noise generator which includes a digital means such as a shift register for generating noise signals wherein the output of the shift register is fed via a filtering means to a transducer means such as a speaker for converting the noise signals to acoustic waves.

Abstract: In a pseudo-random number sequence generator, a random access memory is provided having a plurality of storage locations, each storage location having a number or bit pattern stored therein. A first number is accessed and read by a function generator. A second number is accessed, and an operation such as modulo two addition is performed on the first and second numbers, with a result being provided. Further numbers can be accessed and logically combined with one another, or with the previous result. The operations can all be identical, or may be mixed, so that, for example, some exclusive OR and some AND functions are performed. The result comprises an output digit and can also be written into the second storage location to replace the second number, or intermediate results can be loaded into this location. In successive cycles, the storage location having the most recently produced result comprises the first location, and a next storage location comprises the second storage location for that cycle.

Abstract: An analgesic noise generator employs a circuit that can be switched to provide a variable waveform from an active noise source out of an integrated circuit amplifier.

Abstract: A means and method for generating random permutations on a square having k.sup.2 subsquares based upon a circuitry including a maximal-length sequence generator.

Abstract: A pseudo-random binary sequence having a long period duration is generated by producing a plurality of respectively different first binary signal sequences, supplying at least one of the first signal sequences to at least one input of a feedback connected shift register having an original signal sequence in order to produce an interfering signal which alters the signal sequence being produced by the shift register, and interchanging the first signal sequences supplied to the shift register under the control of signals from a setting program and/or control signals derived from the signal sequences produced in the course of the process. When more than one shift register output is employed, the signals at the outputs are linked together by a logic circuit to form the pseudo-random binary signal sequence of long duration.

Abstract: An improved noise loading arrangement and method are disclosed capable of measuring low intensity intermodulaton distortion products, such as introduced in the operation of individual wideband transmission repeaters. The improved arrangement and method also have the further capability of resolving individual orders of distortion products. The arrangement utilizes a noise signal generator that produces a pseudorandom signal made of several spectral components providing high spectral density throughout a large bandwidth to simulate a broadband message load obtained by frequency multiplexing several independent signal sources. The noise signal is shifted in frequency before a quiet band is produced in the signal applied to the transmission apparatus to be tested. The orders of intermodulation distortion products appearing in the quiet band of the output signal of the transmission apparatus are individually measured to evaluate same.

Abstract: A frequency signaling circuit includes a plurality of channels, each channel having division means for frequency division of a clock signal, the division ratio being selected in accordance with data defining the required frequency. Stochastic conversion means are provided for converting the output of the frequency division means into pulse trains with the repetition rate of the required frequency. The stochastic conversion means includes a noise generating circuit, a value generating circuit for generating signals representing a predetermined sequence of values at a rate determined by the output of the division means and a comparison circuit for comparing the values produced by the value generating circuit with the values represented by the outputs of the noise generating circuit and for producing a pulse whenever a predetermined relation exists between the values.

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 pseudo-random counter, comprising any conventional shift register having a plurality of flip-flop stages, affords counting capability in two directions, either left or right, by providing logic circuit means for generating from the flip-flop outputs a first repetitive logic bit stream which is shifted to the right in response to one gating signal and a second repetitive logic bit stream which is shifted to the left in response to another gating signal, with the two bit streams being mirror images of each other and applied to the register such that the binary output of the register after advancing the count by any number of clock pulses in the presence of one of the gating signals is the same as the binary output which would have been obtained by regressing the count by the same number of clock pulses in the presence of the other gating signal.

Abstract: The disclosed circuit provides a signal generator which is particularly adapted for use as an audible "kilo-sonic" game device in which a plurality of switches are provided so that the different combinations of switch positions produce a corresponding number of different sounds. The circuit includes a voltage-controlled-oscillator (VCO) having an output coupled to a transducer such as a speaker. The VCO is modulated in accordance with a control signal, provided by an up-down staircase generator which is responsive to a pulse generator, to vary the frequency of its output signal. The output of the pulse generator is also selectively coupled with the output of the staircase generator.

Abstract: A method and apparatus for obtaining an accurate measure of a transfer function of either a linear or the linear part of a nonlinear system. This is accomplished by utilizing an estimation technique using a "periodic-random" stimulus consisting of a random stimulus of a finite record length that is repeatedly applied to the system under test until the stimulus and the system response become essentially periodic. Once periodicity is achieved within the desired accuracy, a first estimate of the transfer function is derived from the measured spectrums of the stimulus and the system response. Another "periodic-random" stimulus, uncorrelated with prior records, is then generated and the above procedure is repeated to achieve an average value of the transfer function within the desired accuracy.

Abstract: Behavior modification method involving the use of a portable random interval signal generator. One disclosed embodiment has an increasing probability of obtaining a signal through a time interval. In another disclosed embodiment the probability of obtaining a signal remains constant with time. The method involves analyzing behavior at randomly occurring intervals and in a preferred form recording instances of predefined behavioral classes on a pair of counters associated with the interval generator. Another method involves providing feedback to the subject in the form of reinforcing or punishing events.

Abstract: A method is obtained for generating pseudo-random bit sequence words which is characterized in that the bit contents of a given number of elements of the main register are used as an address for reading out from a memory of a corresponding superposition bit sequence of a length equal to the length of the main register and the bit sequence of a number of given elements of the main register are selected as a first word of the series.

Abstract: 6. In a pulse generating system, means for producing irregular pulses in each of a number of separate circuits, an output for each of said circuits, a pair of holding devices for each of said circuits, means for connecting said holding devices one at a time to their respective circuits and means for combining pulses impressed on each of said outputs from said several circuits with other pulses from a corresponding one of said holding devices.

Abstract: 1. In a pulse-producing system, a plurality of space discharge tube ring circuits each comprising a different number of stages, the numbers of stages in the rings having no common factor greater than one, means to cause said rings to step in unison, means to derive output voltage pulses from certain stages of individual rings and spaces from the other stages, and means to combine the outputs of all of said rings in a common utilization circuit.

Abstract: 1. A key generating circuit for constructing a six-valued key by combination of signals of smaller ranges of values comprising means to produce two-valued signals of highly irregular occurrence, one signal having the values 0 and 1 unit, and the other having the values 0 and 3 units, means to produce a three-valued signal having the values 0 and 2 and 4 units occurring in irregular sequence, means to combine all of said signals in additive manner, and means effective when the summation signal has the value 6 units or a greater value for reducing such value by 6 units.

Abstract: Disclosed are signal generators for developing multilevel output signal sequences of a preselected period of repetition. In their general form, the generators comprise a shift register capable of storing multilevel signals, and feedback means. The feedback means multiply the output signal of prescribed shift register stages by selected integers, add the multiplied signals in nonmodulo arithmetic, and apply the added signals to the first stage of the shift register. The multiplying integers within the feedback means are selected to cause the characteristic functions of the signal generator to be a cyclotomic polynomial. For descriptive convenience, the disclosed generator is termed a "cyclotomic circuit." The disclosed cyclotomic circuits are particularly useful in a minimum memory, prescribed-period, signal generator applications. The minimum memory is achieved by separating the prescribed period into power-of-prime factors, and by associating with each factor a cyclotomic circuit.

Abstract: A biased sequence of binary bits is produced such that the probability that any randomly selected bit will be a "1" is equal to a preselected desired number.

Abstract: 1. A magnetron discharge device for noise generation comprising an elongated cathode, a plurality of spaced anode segments surrounding said cathode to define a cylindrical space charge chamber, and means for establishing a radial electric field between said cathode and said anode segments for imparting an average rotational velocity about the cathode to an electronic space charge when a magnetic field is axially directed through the space charge chamber, said spaced segments and the gaps between them differing in relative widths whereby electrons traveling under different segments and gaps have different transit times.

Abstract: Apparatus for deriving two output numbers generate a first number and provide a second number having a plurality of digit places by subjecting the first number to a predetermined mathematical operation, and derive one of the two desired output numbers from a first digit place of the second number and the other of the two desired output numbers from a different second digit place of the second number.

Abstract: The present system generates a local PN (Pseudo Noise) sequence demodulation bit stream in synchronism with the modulation sequence of a received baseband signal. The system is comprised of a PN sequence generator for generating a local PN sequence signal in response to the pulse rate of a clock signal. A digital delay line generates early and late phases of the local PN sequence, which phases are correlated with the modulation sequence of the received signal. Early correlation causes pulses to be inserted into the train of clock pulses while late correlation causes pulses to be deleted from the train of clock pulses. A phase error less than a predetermined range (dead band) results in no adjustments to the train of clock pulses.

Abstract: A pseudo-random bit generator forms a portion of the pseudo-random code generator, and provides square wave output bits over a defined frequency spectrum on a plurality of parallel output lines. The bits present on a selected number of output lines in sequence define a binary number, which is compared with an accumulated count present in a counter driven by a clock running at a predetermined frequency. A correct comparison resets the counter, shifts the pseudo-random bit generator, and shifts a past-history shift register which contains a portion of the output of the pseudo-random code generator. The output from the past-history shift register, and the square wave output bits on certain other parallel output lines from the random bit generator are applied as inputs to respective logic probability circuits.

Abstract: A noise generator system is described in which the amplitude of a noise source is stabilized by a feedback loop to an automatic gain control circuit, and wherein the output of the system is time controlled by means of a differential pair amplifier.

Abstract: 1. A magnetron discharge device for noise generation comprising an elongated cathode and a plurality of anode segments surrounding said cathode to define a cylindrical space charge chamber, said cathode comprising a helix having a diameter equal to at least half the space charge chamber diameter and having a spacing between adjacent turns equal to at least half the helix diameter.

Abstract: A nonpredictable, nondeterministic actuator for switches or the like having two unsynchronized pulse generators delivering pulses to an AND gate which passes an actuating signal only when the pulses from the generators are coincidental. One generator produces a pulse train at a frequency much higher than the other generator which produces very short pulses and has a maximum timing uncertainty or jitter which is greater than the period of the first mentioned generator.

Abstract: A measurement averaging counting apparatus employing a randomly phase modulated time base provides resolution improvement when measuring an applied signal comprising time intervals or pulsed frequencies repetitively occurring at rates synchronous to a counter's clock frequency.The phase of a reference frequency is varied in response to a random signal. The phase modulated reference frequency is applied to a frequency multiplier chain which multiplies both the frequency and the effective amount of phase modulation. The randomly phase shifting output of the frequency multiplier chain is applied as a clock signal to a measurement averaging counter thereby destroying coherence between the clock signal and the applied signal and allowing statistical averaging to take place.