Showing papers on "Injection locking published in 1972"
TL;DR: In this article, a hybrid injection-locking technique was proposed to stabilize a higher power CO 2 ring laser by locking with a stable low-power reference laser, where the higher power laser is tuned to operate on a self-oscillation line different from that of the reference laser.
Abstract: Frequency stabilization of a higher power CO 2 ring laser by locking with a stable low-power reference laser is described. Successful locking is achieved by employing a novel hybrid injection-locking technique. In the hybrid mode, the higher power laser is tuned to operate on a self-oscillation line different from that of the reference laser. Within the frequency-locking range, the self-oscillation of the locked laser is completely quenched, and only the amplified drive power of the locking laser appears. Operation of this hybrid technique relies on the line competition in the homogeneously broadened CO 2 medium. The hybrid technique, which is easily implemented with a simple hill-climbing servo, permits stabilized operation over a variety of laser lines. An analysis of injection locking that explicity includes the saturation of the homogeneous medium is presented. Expressions are obtained for the gain and the phase relationships within and outside the locking region. To demonstrate the potential of the hybrid injection-locking technique, a 60-W CO 2 laser was locked in frequency to a 0.5-W stable oscillator. The experimental data are in close agreement with theory.
61 citations
Patent•
21 Aug 1972
TL;DR: In this paper, a data recovery system includes means for injection locking a variable frequency oscillator directly with raw data from a magnetic recording disc during the beginning of a read data operation.
Abstract: A data recovery system includes means for injection locking a variable frequency oscillator directly with raw data from a magnetic recording disc during the beginning of a read data operation in order to rapidly lock the variable frequency oscillator in phase with the incoming raw data signals. Desirably, the variable frequency oscillator includes an LC oscillator circuit, which provides excellent noise immunity.
30 citations
01 Mar 1972
TL;DR: In this article, a general form of this function is introduced for RC oscillators of the second order, and expressions for the required maintenance gain and the oscillation frequency are derived.
Abstract: It is assumed that a sinusoidal RC oscillator consists of a linear, passive or active RC network and an amplifier. The properties of such an oscillator are primarily dependent on its open-loop voltage transfer function. A general form of this function is introduced for RC oscillators of the second order, and expressions for the required maintenance gain and the oscillation frequency are derived. It is shown that there exist four distinct types of 2nd-order oscillators. A set of basic building elements for the oscillators is proposed. This consists of some simple RC networks, a voltage divider, a buffer and two amplifiers. The theory and the building elements are used to develop 18 novel oscillator circuits. All these oscillators have either two earthed tuning capacitances or two earthed resistances. It is shown that six of them can be tuned by varying only one capacitance or resistance. Eight of the oscillators are tunable by varying a voltage parameter; in four of these, the voltage-tuning range can be very wide. 14 additional 2nd-order oscillators are suggested. A general 3rd-order RC oscillator is also considered, and it is shown that there exist 15 distinct kinds of this oscillator. The procedure used in the development of the 2nd-order oscillators can also be applied to the design of those of the third order. It is thought that this will lead to a very large number of different oscillator circuits.
18 citations
01 Jun 1972
TL;DR: In this paper, the response time of an amplitude-controlled harmonic oscillator has been greatly reduced by the use of sampling techniques in the control loop, which has been shown to improve the performance of the oscillator.
Abstract: The response time of an amplitude-controlled harmonic oscillator has been greatly reduced by the use of sampling techniques in the control loop.
15 citations
Patent•
28 Sep 1972TL;DR: In this article, the output of an oscillator is fed into a delay line and the phase difference across the delay line is compared in a comparator which gives a d.c. signal.
Abstract: The output of an oscillator is fed into a delay line and the phase difference across the delay line is compared in a comparator which gives a d.c. signal. This d.c. signal is fed back to control the oscillator. The oscillator will normally sit at one of a number of locking frequencies spaced apart so that the delay line gives a zero phase difference but by applying a compensating d.c. signal the oscillator can be set to any intermediate frequency. A square wave pulse is used to cause the oscillator to jump in frequency to the next locking frequency.
12 citations
01 Jul 1972
TL;DR: In this article, an alternative theory to determine the stability of locking with large signal injection is presented, which is based on the first-order theory previously developed for FM amplifications, however, the firstorder theory is inadequate.
Abstract: Injection-locked oscillators are increasingly being used as FM amplifiers. When the injection signal is large, as commonly used for FM amplifications, however, the first-order theory previously developed is inadequate. An alternative theory to determine the stability of locking with large signal injection is presented.
10 citations
TL;DR: In this paper, a Pal glass delay line is used, with a phase detector in a feedback arrangement, to phase-lock a voltage-controlled oscillator between 3 and 6 MHz.
Abstract: An oscillator has been devised which can be continuously tuned over a 2 : 1 frequency range, and which has a stability and spectral purity approaching that of a quartz-crystal oscillator. A Pal glass delay line is used, with a phase detector in a feedback arrangement, to phase-lock a voltage-controlled oscillator between 3 and 6 MHz. The frequency stability is, in the limit, determined only by the phase stability of the delay.
8 citations
Patent•
04 Jan 1972TL;DR: In this paper, the outputs from the injection-locked oscillators are successively coupled together by means of a succession of quadrature couplers whose transmission and reflection coefficients are a function of the amplitudes of the signals incident thereon.
Abstract: Injection-locking is employed to produce phase coherency among a plurality of otherwise free-running incoherent oscillators. The outputs from the injection-locked oscillators are successively coupled together by means of a succession of quadrature couplers whose transmission and reflection coefficients are a function of the amplitudes of the signals incident thereon. The output signal power derived from the last of said couplers is the sum of the powers of the individual oscillators.
7 citations
01 Apr 1972
TL;DR: In this article, a solution of a generalized Adler's equation for injection locking is discussed, and the results of calculations for both tuned and detuned injection phase-locked oscillator-amplifiers are presented graphically.
Abstract: A solution of a generalized Adler's equation for injection locking phenomena is discussed. The results of calculations for both tuned and detuned injection phase-locked oscillator-amplifiers are presented graphically. These results are shown to serve as a convenient means to theoretically evaluate the distortion properties of a single-stage injection phase-locked oscillator-amplifier.
6 citations
TL;DR: In this article, a comparison of properties of high-resistivity GaAs oscillator with those of the Gunn and the acoustoelectric oscillator is made from the point of view of application.
Abstract: Comparison of properties of high-resistivity GaAs oscillator with those of the Gunn and the acoustoelectric oscillator is made from the point of view of application The triggered mode of operation of the high-resistivity oscillator is analyzed by measuring the domain characteristic Operations of the oscillator utilizing its distinctive properties, eg, low domain velocity and high photosensitivity, are performed It is pointed out that the oscillator can be used as a long time delay line of electric or optical signals and as a device controlled by optical signals
4 citations
TL;DR: Using a simple nonlinear negative-resistance model for the active element of an oscillator, small-signal locking characteristics are investigated for fundamental, harmonic and subharmonic locking.
Abstract: Using a simple nonlinear negative-resistance model for the active element of an oscillator, small-signal locking characteristics are investigated for fundamental, harmonic and subharmonic locking. For fundamental locking, a large-signal theory has been developed, and its results are compared with those of the well established small-signal theory for both reciprocal and circular injection of the locking signal.
TL;DR: In this paper, a nonlinear relation between the external Q factor and the locking bandwidth of an oscillator was proposed, and the correct value of the Q factor was then obtained by using a certain frequency interval that can be easily read on the locking ellipse in this relation, rather than the LBS.
Abstract: The usual relation between the external Q factor and the locking bandwidth of an oscillator is not valid when the device reactance is nonlinear. The correct value of the Q factor is then obtained by using a certain frequency interval that can be easily read on the locking ellipse in this relation, rather than the locking bandwidth.
TL;DR: A proposed scheme of detection of phase-shift-keyed signals using an injection-locked oscillator the bandwidth of which is much less than the modulation rate can provide nearly ideal coherent demodulation.
Abstract: We analyze a proposed scheme of detection of phase-shift-keyed signals using an injection-locked oscillator the bandwidth of which is much less than the modulation rate. The output of the oscillator is a carrier with essentially all of its modulation removed. We analyze the effect of noise and signal modulation on the phase of this reference tone and compute its effect on the probability of detection error. If a suitable encoder and decoder are used for the transmitted signal, this technique can provide nearly ideal coherent demodulation.
22 May 1972
TL;DR: In this article, a system for injection locking by angle-modulated signals is presented in which both the locked oscillator and the locking source is angle modulated by the same signal.
Abstract: A system for injection locking by angle-modulated signals is presented in which both the locked oscillator and the locking source is angle-modulated by the same signal. This method provides increased locking gain and improved stability against oscillator drift with preserved signal performance. Intermodulation measurements on a low-Q Gunn-oscillator, angle-modulated by a weakly coupled varactor (0.5 dB loss) demonstrated the expected effects.
TL;DR: In this paper, a frequency sweep injection locking technique was developed for signal averaging and fast passage studies with a nuclear induction spectrometer, which is suitable for signal sampling and fast passing studies.
Abstract: A frequency sweep injection locking technique, suitable for signal averaging and fast passage studies, has been developed for use with a nuclear induction spectrometer.
TL;DR: In this paper, an expression for the differential cross section characterizing the resonant scattering of light by a perturbed harmonic oscillator is given, where it is assumed that the perturbation give rise to a Markovian modulation of the oscillator frequency.
TL;DR: In this paper, a new method of measuring the admittance of microwave oscillators is proposed, where the variable passive load is replaced by an isolator and another oscillator (a signal generator).
Abstract: A new method of measuring admittances of microwave oscillators is proposed. In a usual method, changes of the output power of the oscillator and the oscillation frequency are measured by varying the admittance of a passive load. However, in a new method the variable passive load is replaced by an isolator and another oscillator (a signal generator) and even a positive admittance of the oscillator can be measured. A measurable range by this method is also discussed compared with that by the usual method.