Showing papers on "Total harmonic distortion published in 1972"
Patent•
30 Mar 1972TL;DR: In this paper, a balanced mixer circuit using two matched integrated circuit field effect transistors as active elements is presented, where one input signal is applied to the gates of the transistors in push-pull relationship and a second input signal to the substrates of the Transistors in a common mode push-push manner.
Abstract: Balanced mixer circuit apparatus using two matched integrated circuit field effect transistors as active elements wherein one input signal is applied to the gates of the transistors in pushpull relationship and a second input signal is applied to the substrates of the transistors in a common mode push-push manner. Both input signals thus look into capacitive loads which for practical purposes can be considered to be open circuits, thereby averting any harmonic distortion which might otherwise be produced by loading of the input drive circuits.
29 citations
TL;DR: In this paper, a method of generating sinusoidal voltage-controlled oscillators (VCO) and/or current controlled oscillators suitable for integrated circuits is presented, where each oscillator circuit contains two fixed resistances, two fixed capacitances, and amplifiers.
Abstract: Sinusoidal oscillators with large tuning range and small harmonic distortion offer various applications in integrated electronics. In this paper a method of generating sinusoidal voltage-controlled oscillators (VCO) and/or current-controlled oscillators suitable for integrated circuits is presented. Each oscillator circuit contains two fixed resistances, two fixed capacitances, and amplifiers. It is shown that one amplifier can be used to confine the natural frequencies of the circuit on the j axis of the complex frequency plane, and the other amplifier (or amplifiers) can be used to effectively increase or decrease the RC time constant and hence change the oscillation frequencies.
24 citations
Patent•
16 Nov 1972
TL;DR: In this paper, a phase matched optical wave generator is described, where a harmonic optical wave is generated by the interaction of a fundamental optical wave with a non-linear polarizing material, and the harmonic wave is coupled to a thin-film optical waveguide which is tuned to the wavelength of the harmonic oscillator.
Abstract: A phase matched optical wave generator is described wherein a harmonic optical wave is generated by the interaction of a fundamental optical wave with a non-linear polarizing material. The harmonic wave is coupled to a thin-film optical waveguide which is tuned to the wavelength of the harmonic optical wave. The separation of the fundamental and harmonic waves in different optical waveguides facillitates phase matching over the length of the interacting region to produce a harmonic of enhanced intensity. Several embodiments are shown and described.
17 citations
TL;DR: By linearly sweeping the frequency of the sinusoidal input signal over the range of frequencies of interest, the frequency-response profile of the biological system can be rapidly determined and swept-frequency-system identification technique is described.
Abstract: The paper describes the application of a swept-frequency-system identification technique to biological systems. By linearly sweeping the frequency of the sinusoidal input signal over the range of frequencies of interest, the frequency-response profile of the biological system can be rapidly determined. System transfer characteristics are extracted from the input-power spectral density and output-input crosspower spectral-density computations. Noise, harmonic distortion and sweeptime considerations are given. Logarithmic frequencysweeping is suggested as a means of avoiding harmonic distortion.
14 citations
Patent•
14 Aug 1972TL;DR: In this paper, an apparatus for converting a square wave signal to a sine wave signal with a fixed predetermined phase relation to the square wave signals is described, where the sine waves are sampled as a function of the square waves and a feedback circuit is provided to produce a correction signal representing the phase relation there between.
Abstract: An apparatus is disclosed for converting a square wave signal to a sine wave signal wherein said sine wave signal maintains a fixed predetermined phase relation to the square wave signal. A feedback circuit is provided which samples the sine wave signal as a function of the square wave signal and produces a correction signal representing the phase relation therebetween. A sine wave generator is responsive to the square wave signal and the correction signal for producing the sine wave signal in a fixed predetermined phase relation to the square wave signal.
12 citations
TL;DR: In this paper, the design and applications of high voltage range series current regulators are discussed and a sample design maintains the current to within 1% of a selected value between 100 μA and 50 mA over a 15 kV voltage range.
Abstract: The design and applications of high voltage range series current regulators are discussed. A sample design maintains the current to within 1% of a selected value between 100 μA and 50 mA over a 15 kV voltage range. The regulator is ideal for regulating or pulsing laser gas discharges. The circuit can also be used as a high output voltage amplifier; in this service it can deliver 10 kV at 5 kHz with 1.4% total harmonic distortion.
10 citations
TL;DR: In this article, a transfer characteristic of the drain-source channel was obtained for short-gate structures, where field-dependent mobility was taken into account in the equations for the drain current, and the distortion products M 2 and M 3 were derived from this type of characteristic.
Abstract: It has been found that a harmonic analysis of the usual power-law transfer characteristic of the JFET does not yield equations which accurately predict the third-harmonic distortion products for short-gate structures. However, if field-dependent mobility in the drain-source channel is taken into consideration in the equations for the drain current, a transfer characteristic is obtained of the form 3Z_{D}(1-e^{-r})/ \Gamma^{2} , where Z D is the normalized channel height and Γ is the field factor. Equations for the distortion products M 2 and M 3 , which are derived from this type of characteristic, accurately predict M 2 and M 3 for actual devices as a function of physical parameters. Lower limits on the values of M 2 and M 3 which can be achieved in a practical JFET are presented.
7 citations
TL;DR: In this article, the results of digital and transient network analyzer (Anacom) studies were analyzed with respect to their effect on harmonics in steady-state overvoltages.
Abstract: Steady-state overvoltages can occur on EHV transmission systems during various system operating conditions. The voltage waveforms are characterized by a periodic waveform which may be distorted by harmonics if iron saturation of equipment on the lines occurs. This paper discusses the results of digital and transient network analyzer (Anacom) studies which analyzed system parameters with respect to their effect on harmonics in steady-state overvoltages. Special emphasis was focused on the factors influencing harmonic distortion of the steady-state voltages.
5 citations
Patent•
15 Aug 1972
TL;DR: In this paper, an adjustable frequency generator with low harmonic distortion was proposed, which consists of an adjustable R.F. oscillator, a variable bandwidth low pass filter, a detector and a comparator.
Abstract: An adjustable frequency generator equipment having automatically controlled output level and low harmonic distortion comprises an adjustable R.F. oscillator, a variable bandwidth low pass filter, a detector and a comparator. The detector, at the output of the filter, provides a D.C. output proportional to the R.F. input thereto. This D.C. voltage is fed to one terminal of the comparator, and the output from the comparator controls varactor diodes in the filter, thereby automatically adjusting the upper cut-off frequency of the filter to a value close to the fundamental frequency of the oscillator. The output level of the equipment is adjusted by varying the reference voltage applied to a second terminal of the comparator.
4 citations
TL;DR: The results have been interpreted as indications that electromechanical and hydromechanical nonlinearities dominate the distortion process over low‐ and high‐intensity ranges.
Abstract: The effects of dc polarization of the cochlear partition were observed on harmonic distortion components in microphonics. The qualitative effects of negative polarization (scala vestibuli negative) were quite consistent and similar to those observed in the polarization of intermodulation distortion components. The effects of positive polarization were much more variable, but the general trends of the data suggest that when the stimulus is presented below 85–95 dB SPL, the harmonic distortion output is enhanced by both positive and negative polarizing currents. At higher intensities, these components behave much as the fundamental microphonic component. These results have been interpreted as indications that electromechanical and hydromechanical nonlinearities, respectively, dominate the distortion process over low‐ and high‐intensity ranges.
4 citations
TL;DR: It is shown that the results obtained by treating the discriminator as a degenerate FMFB compare favorably with those obtained by other authors, however, the results presented here do not require digital computation.
Abstract: The response of a frequency demodulator using feedback (FMFB) to a frequency modulated signal is analyzed. Canonical equations of operation are obtained. Harmonic distortion is calculated for the case of a sinusoidal modulating signal. Intermodulation distortion is calculated assuming a noise-like modulation. Design curves are presented. The special case of harmonic and intermodulation distortion in a discriminator is also presented. It is shown that the results obtained in this paper by treating the discriminator as a degenerate FMFB compare favorably with those obtained by other authors. However, the results presented here do not require digital computation.
TL;DR: A technique for the design of large-signal amplifiers for minimum distortion is presented that takes advantage of the frequency-domain aspects of the problem by using the fast Fourier transform.
Abstract: A technique for the design of large-signal amplifiers for minimum distortion is presented. This technique takes advantage of the frequency-domain aspects of the problem by using the fast Fourier transform.
TL;DR: The performance of a V.H.F. tuner under strong signal reception is limited by the nonlinear effects that take place either in the R.C. or the mixer stages as discussed by the authors.
Abstract: The performance of a V.H.F. tuner under strong signal reception is limited by the nonlinear effects that take place either in the R.F. or the mixer stages. These nonlinearities will either modify the amplitude of the incoming signal (cross-modulation or overload) or generate new frequency components (inter-modulation or harmonic distortion).