LIMITATIONS DETERMINED IN "NOSE-TO-NOSE" IMPULSE RESPONSE METHOD.NIST (National Institute of Standards & Technology, Washington, DC, www.nist.gov) The standards-defining agency of the U.S. government, formerly the National Bureau of Standards. It is one of three agencies that fall under the Technology Administration (www.technology. researchers have determined certain limitations on the nose-to-nose technique for characterizing the impulse response In simple terms, the impulse response of a system is its output when presented with a very brief signal, an impulse. While an impulse is a difficult concept to imagine, and an impossible thing in reality, it represents the limit case of a pulse made infinitely short in time of diode-bridge type, high-frequency samplers used in certain commercial 20 GHz and 50 GHz (3 dB bandwidth) equivalent-time, digitizing oscilloscopes. In general, having an accurate estimate for the impulse response of these samplers is important for measurement accuracy; moreover, these diode-bridge type samplers are used by NIST for providing pulse waveform calibration services. Poor estimates for the impulse response of these samplers can degrade TO DEGRADE, DEGRADING. To, sink or lower a person in the estimation of the public. 2. As a man's character is of great importance to him, and it is his interest to retain the good opinion of all mankind, when he is a witness, he cannot be compelled to disclose the uncertainties quoted for the calibration services. In particular, it has established that there are regions of nonlinear behavior in the amplitude and bandwidth of the "kickout" pulses from the diode bridge A diode bridge or bridge rectifier is an arrangement of four diodes connected in a bridge circuit , that provides the same polarity of output voltage for any polarity of the input voltage. sampler sampler, sample piece of needlework or embroidery, of silk, cotton, or worsted, for the preservation of some pattern or as an example of the ability of a child or a beginner. In museums and private collections there are samplers dating from as early as 1643. as a function of offset voltage. The basic technique assumes that these pulses are stable and symmetrical between the samplers used for the nose-to-nose testing procedure. Also, a temperature-dependent time shift (drift) in the kickout pulse was also observed over the manufacturers recommended operating temperature range (15 [degrees]C to 35 [degrees]C). The amplitude of the pulses changed, as expected, but the pulse width pulse width Pulse duration Cardiac pacing The duration of a pacing pulse in msecs was unchanged. These studies have been documented in two papers: "The Effect of Offset voltage on the Kick-Out Pulses Used in the Nose-to-Nose Sampler Impulse Response Characterization Method"; and "Temperature Effects on the High Speed Response of Digitizing Sampling Oscilloscopes, at the 2000 National Conference of Standards Laboratories Workshop and Symposium in July. |
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