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Showing papers on "Phase noise published in 1969"


Journal ArticleDOI
TL;DR: In this paper, the authors provide an insight into low frequency divergent noises with spectral density |f|?, where?? -1, and into their effect on physical measurements, with special reference to 1/|f| noise.
Abstract: The purpose of this paper is to provide an insight into low frequency divergent noises with spectral density |f|?, where ? ? -1, and into their effect on physical measurements, with special reference to 1/|f| noise. This class of noise is widespread in nature, and it presents unique limitations to the measurement accuracy. In an attempt to present a picture of this class of noise with regard to the measurements of observable physical quantities, the questions about generation of noise, its divergence, correlation properties and measurements of variance are discussed. A statistical model for generation of low frequency divergent noises is used to consider the divergence problem in both the frequency and time domain. It is shown that 1/|f| noise is "weakly divergent," and that power limitation presents no reason to impose a low frequency limit within time intervals observable in nature. Correlation properties are discussed in terms of the time-dependent correlation function, using an ideal impulse response which generates low frequency noise from white noise. Two general models for generation of 1/|f| noise are summarized and discussed. Generation of 1/|f| noise from white noise over a limited frequency range by distributed and lumped-parameter filters is described. It is shown that the variance (i.e. mean square noise) is determined by the frequency limits of the observation method.

61 citations


Journal ArticleDOI
TL;DR: In this paper, the effect of noise on the microwave-induced steps in the current-voltage characteristic of a Josephson junction is investigated theoretically, and the dynamic resistance of a step is obtained in the limit that the capacitance of the junction is small.
Abstract: The effect of noise on the microwave-induced steps in the current-voltage characteristic of a Josephson junction is investigated theoretically. The dynamic resistance of a step is obtained in the limit that the capacitance of the junction is small. The phase fluctuations of the junction are greatly reduced in the presence of the microwave signal, and the dynamic resistance can be extremely small.

46 citations


Journal ArticleDOI
TL;DR: In this paper, the amplitude distribution of 1/f noise was investigated by displaying the noise on an oscilloscope, and scanning the picture with a movable slit; the distribution curve is gaussian; its variance does not fluctuate with time.

38 citations


Proceedings Article
01 Jan 1969
TL;DR: Digital data transition tracking loop mean square phase noise computed as function of input SNR by Fokker-Planck technique as discussed by the authors, which can be used to estimate the phase noise of the data.
Abstract: Digital data transition tracking loop mean square phase noise computed as function of input SNR by Fokker-Planck technique

32 citations


Journal ArticleDOI
TL;DR: It is shown that the residual phase noise of film at dc even under so-called matched conditions is large enough to prevent the accurate estimation of the dc value of grain noise.
Abstract: The estimation of the spectral density of a spatial random process by diffraction requires that the parameters of the diffraction system be compatible with the statistical properties of the process. Otherwise, the estimate of the spectrum can be unstable or unduly biased. The relation between the second-order statistics of the process and the parameters of a basic diffraction system that are required for reasonable spectral estimates is investigated. Such parameters include aperture dimensions, wavelength, focal length of the lens, and scanning slit size. With the typical diffraction system, it is difficult to estimate the power spectrum because of the presence of the zero-order aperture-diffracted light. A technique is furnished in this paper for spectral estimation at dc. Experimental results are furnished for film grain and total film noise. It is shown that the residual phase noise of film at dc even under so-called matched conditions is large enough to prevent the accurate estimation of the dc value of grain noise.

27 citations


Journal ArticleDOI
01 Jan 1969
TL;DR: In this paper, the authors performed FM noise spectra measurements on a Gunn oscillator under injection-locked conditions, and the experimental results have shown good agreement with the theory not only qualitatively but quantitatively.
Abstract: FM noise spectra measurements were performed on a Gunn oscillator under injection-locked conditions. The experimental results have shown good agreement with the theory not only qualitatively but quantitatively.

19 citations


Journal ArticleDOI
TL;DR: Because of the excellent results of the noise-loading test on an IMPATT oscillator that is phase-locked to an external FM driving signal, a new microwave amplifier for multichannel FM signals using a synchronized oscillator is proposed.
Abstract: Because of the excellent results of the noise-loading test on an IMPATT oscillator that is phase-locked to an external FM driving signal, a new microwave amplifier for multichannel FM signals using a synchronized oscillator is proposed. An IMPATT oscillator, injection-synchronized with an FM signal, is regarded as an amplifier and its noise characteristics for multichannel signals are evaluated with the noise-loading method as recommended by the International Radio Consultative Committee. The results show that when this oscillator satisfies the noise characteristics for 960 telephone message channels, it assures a gain of approximately 15 dB at 11 GHz, and in this sense, this oscillator can be regarded as an amplifier for multimessage channels. The degradation of SNR of this amplifier is less than 2 dB. This excellent result is obtained because of the following. In the video band, the modulation suppression of an FM driving signal in the injection-synchronized oscillator, such as the IMPATT, is very small, while the oscillator noise, which dominates the entire output characteristic, is considerably reduced by the synchronizing action of the oscillator. This amplification continues up to the high-frequency range in which this principle of operation applies.

13 citations


Journal ArticleDOI
TL;DR: A modified quadrature channel phase-locked-loop demodulator for binary phase-shift-keyed signals is presented and the modification, called decision feedback, is a practical implementation of decisiondirected channel measurement.
Abstract: A modified quadrature channel phase-locked-loop demodulator for binary phase-shift-keyed signals is presented. The modification, called decision feedback, is a practical implementation of decisiondirected channel measurement. Noise analyses are carried out for both additive and phase noise. An optimum loop filter is derived and the analyses include determination of probability of error for the system. The results of an analog simulation of the decision feedback technique are also included.

12 citations


Proceedings ArticleDOI
17 Jun 1969
TL;DR: In this paper, the authors proposed a method to identify an area from observation points located throughout the local hemisphere by combining the dominant individual source spectra and the composite spectrum of area noise sources.
Abstract: The radio noise field is composed of naturally occurring emissions from atmospheric and galactic processes, man-made disturbances and thermal radiation from the local environment. Natural noise processes including thermal radiation contribute the dominant noise at the extremes of the radio spectrum in metropolitan environments but are superseded by man-made noise in the LF to UHF bands. The dominance of man-made noise in the center of the radio spectrum arises from coherent interference of entertainment, communication, and navigational equipment and the incoherent emissions of transportation, utility, industrial and commercial equipment. The source emission spectra and the propagation characteristics of the source-to-detector space control the noise intensity. The intensity of coherent noise is predictable from a knowledge of the number, location, modulation and carrier frequency of the sources and the physical properties and features of the transmission space. The intensity of incoherent interference is similarly dependent but complicated by being produced from statistically random processes. The prediction and ultimately the control of incoherent radio noise is yielding to analyses and measurements which combine examinations of the dominant individual source spectra and the composite spectrum of area noise sources. The multi-dimensional area signatures of composite, incoherent radio noise can be used to identify an area from observation points located throughout the local hemisphere.

10 citations


Patent
12 Nov 1969
Abstract: A receiver for detecting phase reversed binary information wherein the phase reversal is accomplished linearly over one clock period by slightly increasing or decreasing the carrier frequency. A variable frequency local oscillator tuned to the carrier frequency is mixed with the phase modulated carrier signal and then averaged by a first filter. When the oscillator is at the proper phase, the output of the first filter will be a binary signal. A pair of feedback loops detect and compare in a subtractor and a second filter the rectified outputs of a pair of mixers which beat the phase modulated carrier signal with plus and minus 45* components of the oscillator signal. When the oscillator is at the proper phase, the energy from both mixers in the feedback loop will be equal. When the oscillator phase is incorrect, the energy in the loops will be different and the output of the second filter will then increase or decrease slightly the oscillator frequency until the proper phase is reached.

9 citations


Journal ArticleDOI
TL;DR: In this paper, a cavity-controlled Gunn oscillator is investigated both theoretically and experimentally. And the susceptance of a GaAs Gunn diode fluctuates following velocity fluctuations of high field domains.
Abstract: FM noise in a cavity-controlled Gunn oscillator is investigated both theoretically and experimentally. The susceptance of a GaAs Gunn diode fluctuates following velocity fluctuations of high field domains. This results in FM noise. The fluctuations of the velocity are considered to be due mainly to those of carrier concentration fluctuations. Measured FM noise is in good agreement with the model, verifying that fluctuations of carrier concentration result in FM noise in the oscillator. When the quality factor Q ex of the resonant cavity used becomes large, the FM noise characteristic deviates from the theoretical one based on the fluctuations of carrier concentration. The fluctuations of the voltage across the diode in the resonant cavity also influence the domain dynamics and hence the diode susceptance. These seem to be causes of the deviation.

Patent
11 Aug 1969
TL;DR: In this article, a variable frequency oscillator is used to control the position of the output of a fixed-frequency oscillator over a noise frequency band, which is variable by varying the frequency of the variable oscillator.
Abstract: In a ''''while noise'''' test set a mixer is fed from a source of white noise via a narrow band-stop filter and from a variable frequency oscillator, a predetermined band of frequencies from the output of the mixer being fed to a second mixer with oscillators from a fixed frequency oscillator. The arrangement is such that the output from the second oscillator consists of a noise frequency band including a narrow ''''silent slot,'''' the position of which is variable over said band by varying the frequency of the variable frequency oscillator.

Journal ArticleDOI
TL;DR: The former portion of the paper discusses the relation of the phase-locked loop to Kalman-Bucy filter theory and presents a demodulator design that illustrates the self-adaptive properties attainable in phase-lock loops with signal clipping.
Abstract: Employing techniques similar to the averaging methods of Krylov and Bogoliubov, an approximate noise analysis of the phase-locked loop with signal clipping is presented. The validity of the method is demonstrated by comparing the stationary probability density function for the phase error, generated by a system simulation, with the derived theoretical results. The latter portion of the paper discusses the relation of the phase-locked loop to Kalman-Bucy filter theory and presents a demodulator design that illustrates the self-adaptive properties attainable in phase-locked loops with signal clipping.

Journal ArticleDOI
TL;DR: Quantum phase noise in He-Ne laser, considering amplitude fluctuation, spontaneous emission and oscillator linewidth was studied in this article, where the authors considered a single HeNe laser.
Abstract: Quantum phase noise in He-Ne laser, considering amplitude fluctuation, spontaneous emission and oscillator linewidth

Journal ArticleDOI
TL;DR: In this article, the results of injection phase locking to a master oscillator and through the use of high-Q cavities are presented for a class of high frequency oscillator-high-order multiplier and avalanche-diode oscillator microwave sources.
Abstract: Results of noise-reduction techniques by injection phase locking to a master oscillator and through the use of high-Q cavities are presented for a class of high- frequency oscillator-high-order multiplier and avalanche-diode oscillator microwave sources. Frequency and amplitude noise spectra are described for two states of oscillation: free-running and injection phase-locked for the video range 300 hertz to 10 MHz off the carrier frequency. At X band, a rms noise deviation less than 0.15 hertz in a 100-hertz bandwidth has been achieved at frequencies greater than 10 kHz off the carrier for the free-running high- frequency oscillator-high-order multiplier source. Corresponding results obtained for a free-running avalanche- diode oscillator was a flat 6-hertz spectrum across the video range 1 kHz to 100 kHz.

Journal ArticleDOI
TL;DR: In this paper, the sync separator vertical take off, horizontal oscillator, automatic frequency control (AFC), automatic phase control (APC), and a noise blanking circuit are combined in a single monolithic chip.
Abstract: Five circuit functions required in a television (TV) receiver - namely, the sync separator vertical take off, horizontal oscillator, automatic frequency control (AFC), automatic phase control (APC), and a noise blanking circuit - have been successfully combined in a single monolithic chip. This approach demanded a deviation from accepted discrete design principles and resulted in circuitry requiring only one half as many total components as previously used, while at the same time giving superior performance. Some features, besides the obvious space and power dissipation advantages common to IC technology, include the elimination of a feed-back winding on the fly back transformer for the APC and the elimination of the horizontal hold control. Also deemed important is the complete lack of coils or transformers for the oscillator itself. This work exdmines the individual circuits within the monolithic structure as well as the ancillary components required for functional performance.

Journal ArticleDOI
TL;DR: In this paper, a frequency-domain interpretation of the phase stability of an oscillator is discussed, based on a knowledge of the time dependence of the oscillator phase during a time interval T *, and the characteristics of this oscillator not only for this time interval, but also for subsequent time intervals.
Abstract: A frequency-domain interpretation of the phase stability of an oscillator is discussed. From a knowledge of the time dependence of an oscillator phase during a time interval T* it is possible to give the characteristics of this oscillator, not only for this time interval, but also for subsequent time intervals. Since the use of a Fourier transform for the computation of a continuous power spectrum is unrealistic, a discrete-spectrum approach will be taken. Usually, in the calculation of power spectra, stationarity of the fluctuations is assumed, although experiment indicates that this is often not the case. A more realistic approach is adopted. Analytical phenomena and random walk are separated from white noise on the basis of statistical criteria using discrete Fourier transforms. The white noise is then interpreted in the frequency domain. Both random walk and specific signals are studied in the time domain and can be separated by digital filtering. Two different sets of experimental results are analyzed by this method, one derived from measurements on a quartz-crystal oscillator locked to a low-frequency transmitter and the second from measurements on an ammonia maser. In both cases, measurement precision and ease of prediction of the behavior of the oscillator are improved.

Patent
29 Jan 1969
TL;DR: In this article, a wave clipping circuit removes one side of a white noise signal, and a switching circuit switches this one-side-removed signal in accordance with bias control between a conducting region and a cutoff region, the wave being caused to enter the cutoff region from the notremoved side during the signal attenuation process in the switching circuit.
Abstract: A switching system in which a wave clipping circuit removes one side of a white noise signal, and a switching circuit switches this one-side-removed signal in accordance with bias control between a conducting region and a cutoff region, the white noise signal wave being caused to enter the cutoff region from the notremoved side during the signal attenuation process in the switching circuit.

Journal ArticleDOI
TL;DR: The features of the FM correlation system are shown in comparison with a conventional correlation system and a detailed analysis of the effect of the envelopes of the narrow-band Gaussian random signals on the output is presented.
Abstract: By the term "FM correlation system," we mean the analog correlation system that consists of two channels, each containing an FM detector. Expressions are derived for the output of the FM correlation system for the following cases. Each channel input to be correlated is a conventional FM signal plus Gaussian noise; and each input is an amplitude-limited or a nonlimited narrow-band Gaussian random signal plus Gaussian noise. The effect of the input carrier-to-noise power ratios is made clear. The features of the FM correlation system are shown in comparison with a conventional correlation system. In addition, a detailed analysis of the effect of the envelopes of the narrow-band Gaussian random signals on the output is presented.


Journal ArticleDOI
TL;DR: In this article, a scheme for digital phase-shift control of a locked oscillator is proposed, where the required operating frequency is f and the locking frequency is nf, under suitable conditions.
Abstract: A scheme for digital phase-shift control of a locked oscillator is proposed. If the required operating frequency is f and the locking frequency is nf, a reversal in phase of the locking frequency will shift the phase of the locked oscillator by π/n, under suitable conditions.

Journal ArticleDOI
TL;DR: In this article, the authors discuss the role of noise role in beat frequency measurements in far IR due to harmonic mixing of klystrons, discussing noise role, and discuss noise role.
Abstract: Beat frequency measurements in far IR due to harmonic mixing of klystrons, discussing noise role

Journal ArticleDOI
TL;DR: In this paper, the amplitudes of a few significant frequency components were investigated and the expression for signal to noise ratio was also established for such a system, and it was concluded that an r.w.m. system has better (S/N) characteristics than the equivalent f.m.-f.m system.
Abstract: On the analogy of f.m.—f.m. systems the frequency spectrum of r.w.m.—f.m. signals is investigated and calculations are made to determine the amplitudes of a few significant frequency components. The expression for signal to noise ratio is also established for such a system. Signal to noise ratios for r.w.m.—f.m. systems and the equivalent f.m.—f.m. systems are calculated and compared for different values of channel bandwidths. It is concluded that an r.w.m.—f.m. system has better (S/N) characteristics than the equivalent f.m.-f.m. system.

01 Jan 1969
TL;DR: In this paper, the absolute value type of early-late gate bit synchronizer phase noise performance determined by Fokker-Planck method was compared with different circuits performance, comparing results with different circuit performance.
Abstract: Absolute value type of early-late gate bit synchronizer phase noise performance determined by Fokker-Planck method, comparing results with different circuits performance

01 Jan 1969
TL;DR: Plasma lasers, investigating striation oscillations and excess noise phenomena and generation mechanisms were investigated in this paper, where the authors proposed a new generation mechanism based on a beamforming scheme.
Abstract: Plasma lasers, investigating striation oscillations and excess noise phenomena and generation mechanisms

Proceedings ArticleDOI
01 Jan 1969
TL;DR: In this paper, a continuous-cathode, forward-wave CFA with a cutoff electrode was examined for intra-spectral noise and phase coherence in the L-band with an average power rating of 3 kW.
Abstract: The high efficiency and relatively low weight of CFA's have made this class of tubes attractive to the radar system designer. However, because questions about their noise characteristics and phase coherence have remained unanswered there has been a hesitancy to specify their use in the more sophisticated system, now being planned. In order to obtain definitive data about these important properties, a continuous-cathode, forward-wave CFA which is operated with a cutoff electrode was examined carefully for intra-spectral noise and phase coherence. The tube tested provides 100 kw of peak power for 100 MHz at L-band with an average power rating of 3 kW.

Journal ArticleDOI
A. Cense1, J. Rongen1
01 Aug 1969
TL;DR: An IC signal processing circuit that can be applied in both black-and-white and color receivers is described in this article, where the integrated circuit combines the following functions: video preamplifier, keyed AGC detector, operating on top sync level; AGC amplifier for IF and tuner control; noise canceling circuits for AGC and sync circuits; sync separator; automatic horizontal sync; and vertical sync pulse separator.
Abstract: An IC signal-processing circuit that can be applied in both black-and-white and color receivers is described The integrated circuit combines the following functions: video preamplifier; keyed AGC detector, operating on top sync level; AGC amplifier for IF and tuner control; noise canceling circuits for AGC and sync circuits; sync separator; automatic horizontal sync; and vertical sync pulse separator Due to the noise-canceling circuit a stable synchronization is obtained when impulse noise is received Since the values of the capacitors in the AGC circuit can be rather low without difficulties with instabilities, the performance during fast input signal fluctuations (airplane flutter) is very good



Journal ArticleDOI
TL;DR: In this paper, the authors describe the design, construction and testing of an instrument that employs hybrid circuits and realizes, through circuitry, all the observed statistical amplitude and time characteristics of the natural noise bursts in the burst form of the noise in the frequency range 0·1−10 MHz.
Abstract: The testing of radio systems for data communication through the atmospheric burst error channel requires a laboratory source of the burst form of atmospheric radio noise. The paper describes the design, construction and testing of such an instrument. This noise burst generator employs hybrid circuits and, through circuitry, realizes, for the artificial noise bursts, all the observed statistical amplitude and time characteristics of the natural noise bursts in the burst form of the noise in the frequency range 0·1–10 MHz.