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Showing papers on "Dynamic range published in 1970"


Journal ArticleDOI
TL;DR: In this article, a precision slotted-line measurement system is described that provides rapid impedance measurements over a wide dynamic range for both active and passive devices, achieving phase accuracy of 1° at 70 GHz and magnitude accuracy of 05 percent for high VSWR measurements.
Abstract: A precision slotted-line measurement system is described that provides rapid impedance measurements over a wide dynamic range for both active and passive devices Phase accuracy of 01° at 70 GHz and magnitude accuracy of 05 percent are obtainable for high VSWR measurements Phase-locked sources used for both the slotted-line drive and the receiver local oscillator provide greater than 70 dB of dynamic range for an incident power level of -50 dBm at the unknown A micrometer positioner for the slotted-line probe provides an order of magnitude improvement in probe-position accuracy over that obtainable using the conventional slotted-line scale and micrometer A computer program simulates the slotted line and its associated connector by several sections of lossy transmission line together with appropriate discontinuity capacitance and contact loss This form of model has the advantage that frequency dependence is implicitly included Impedance measurement is simple and rapid The only data required are the frequency, the position of an unknown null, either the width of the minimum or the VSWR, and the desired reference plane extension The corrected data may be plotted directly on a Smith chart Printout is in a convenient format for data evaluation

21 citations


Patent
30 Sep 1970
TL;DR: In this paper, an adaptive digital automatic gain control (DAGC) system was proposed for pulsed radar moving target indicator (MTI) systems to reduce the input dynamic range requirements of a data processing and display system by dividing each range sweep into a number of range elements of one or more range bins, and providing a digital error signal indicating whether or not the video signal is greater than the reference signal.
Abstract: An adaptive digital automatic gain control (DAGC) system is disclosed for pulsed radar moving target indicator (MTI) systems to reduce the input dynamic range requirements of a data processing and display system by dividing each range sweep into a number of range elements of one or more range bins, comparing the signal level in each range element to a selected reference level, and providing a digital error signal indicating whether or not the video signal is greater than the reference signal. The radar video signal is processed by an MTI filter, the output of which is compared with a selected reference level to similarly provide digital error signals for AGC control based on not only the raw radar video signal, but also the MTI video signal. These digital error signals are integrated separately for each range element, thereby developing for each range element an AGC signal in digital form based on the past history in the raw radar video signal and the MTI video signal over a continuous succession of range sweeps. After conversion into analog form, these digital AGC signals developed for all range bins of a given sweep are filtered by a low pass filter to provide an analog AGC signal which is smooth over approximately 16 range bins. A noise AGC signal is similarly developed and combined with the radar video and MTI video AGC, but at a much slower rate of one sample per azimuth scan.

11 citations


Journal ArticleDOI
TL;DR: In this article, a simple compact recorder suitable as an alternative to the oscilloscope camera combination is described, which is read out either electronically or by observing a magnetic domain wall which represents the recorded signal.
Abstract: A simple compact recorder suitable as an alternative to the oscilloscope‐camera combination is described. The risetime of the recorder is 2 nsec and it has a dynamic range of 30 dB. The information is read out either electronically or by observing a magnetic domain wall which represents the recorded signal.

6 citations


PatentDOI
TL;DR: Computer means are provided to automatically rotate the pattern function of the combination of the dipole hydrophones in the system to reduce the dynamic range requirement of an underer sound system by minimizing the effects of noise interference.
Abstract: Means are provided for reducing the dynamic range requirement of an underer sound system by minimizing the effects of noise interference. Computer means are provided to automatically rotate the pattern function of the combination of the dipole hydrophones in the system. A minimum noise pattern position is derived from hydrophone output information.

4 citations


Journal ArticleDOI
TL;DR: In this article, the operation of a high-dynamic-range parametric amplifier is described, where the varactor is a GaAs p-n junction with an n type layer suitable for operation as a K band transferred-electron oscillator.
Abstract: The operation of a high-dynamic-range parametric amplifier is described. The varactor is a GaAs p-n junction with an n type layer suitable for operation as a K band transferred-electron oscillator (t.e.o.). A dynamic range of approximately 177 dB/Hz and a noise figure of less than 2 dB were measured at C band. The tests were made to show the feasibility of high-dynamic-range low-noise microwave amplification for radar-receiver applications, and to establish the feasibility of high-performance monolithic multifunction chips from the material standpoint.

2 citations



Journal ArticleDOI
TL;DR: The Bruel & Kjaer type 3347 real-time 13-oct analyzer is made especially for the acoustical and vibrational field of measurements, for quasistationary periodic and random signals as mentioned in this paper.
Abstract: Bruel & Kjaer type 3347 real‐time 13‐oct analyzer is made especially for the acoustical and vibrational field of measurements, for quasistationary periodic and random signals. A bank of 13‐oct band analog filters, true rms detectors, and storage circuits make up the analyzing package. This is followed by a digital multiplexer and a logarithmic analog‐digital converter featuring both analog and digital outputs. Special emphasis is laid upon the inclusion of a precision and impulse sound‐level meter (per IEC 179), as well as perfect syncronism between parallax‐free display scope and digital information. The total accuracy of filters and detectors is 0.5 dB. Instrument dynamic range is 150 dB, display range 50 dB. The frequency range is 22.4–45 000 Hz with 32 filters. Furthermore, four weighting networks D, A, B, and C, and a linear network are supplied with detectors suited for wide‐frequency measurements. Signal averaging is done by running exponential integrators with three selectable time constants. A tim...

1 citations


15 Nov 1970
TL;DR: The hydrophone-preamplifier described in this paper has a frequency band from a few hertz to above 50 kHz, a voltage gain of 6 dB and a maximum input voltage for linear operation of 10 V peak-to-peak; it is therefore particularly suitable for experiments with explosive sound sources.
Abstract: : The hydrophone-preamplifier described has a frequency band from a few hertz to above 50 kHz, a voltage gain of 6 dB, and a maximum input voltage for linear operation of 10 V peak-to-peak; it is therefore particularly suitable for experiments with explosive sound sources. Its very low equivalent input noise permits the acquisition of signals only just above zero-sea-state noise level, its input dynamic range of better than 130 dB allows its use with a digital recording system, and its 100 megohm input impedance makes it suitable for low frequency signals even when using low-capacitance hydrophones. An output transformer has been used to minimize crosstalk transmission of the output signal in a multipair cable and an internal voltage regulator provides optimum decoupling when various units are supplied by the same power line from the research ship. The use of highly reliable components has been combined with a rugged construction. (Author)

1 citations


Journal ArticleDOI
TL;DR: In this paper, the use of photovoltaic diodes as logarithmic detectors has been investigated and an analysis of the response of the diode shows that the dynamic range of the device decreases with increased loading.
Abstract: The use of photovoltaic diodes as logarithmic detectors has been investigated. An analysis of the response of the diode shows that the dynamic range of the device decreases with increased loading. Experimental measurements on diffused GaAs diodes, which have threshold sensitivities in the 1-10 nW/cm2range, confirmed this analysis.