Topic
Output impedance
About: Output impedance is a research topic. Over the lifetime, 11185 publications have been published within this topic receiving 134949 citations.
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Patent•
29 Jan 1992
TL;DR: In this article, a phase-locked loop is used to track both frequency offset and phase of the far echo separately from the adaptation of the emulator parameters, and initial training of the canceller is performed with a simple cyclic training signal.
Abstract: When the transmitter and receiver of a duplex multicarrier modem are connected to a two-wire line, echoes of the transmitted signal are reflected back into the receiver by mismatches between the output impedance of the modem and the input impedance of the line. These echoes are cancelled by an echo emulator which operates on samples of the transmitted signal. The parameters of the emulator are adapted by correlating, in the frequency domain, the transmitted data with the received signal. A specialiyed phase-locked loop, which uses a unique phase detector, tracks both frequency offset and phase of the far echo seperately from the adaptation of the emulator parameters. Initial training of the canceller is performed with a simple cyclic training signal that allows the use of efficient fast transforms.
34 citations
Patent•
27 Apr 2006
TL;DR: In this paper, the authors proposed a power source and operational method in which a plurality of inverters are connected in parallel with the ability to suppress the crosscurrent with a very simple means.
Abstract: The objective of the present invention is to provide a power source and operational method in which a plurality of inverters are connected in parallel with the ability to suppress the crosscurrent with a very simple means. The present invention is an electric power source in which a plurality of inverted operate on the same frequency and the plurality of inverters are connected in parallel so that a resistance value expressed by (1−β·G)/(α·G) here α is the output voltage feedback gain, β is the output current feed forward gain, and G is the inverter current gain, is made to be the equivalent output impedance; and is an electrical power source in which the cross-current between the inverters are made to be an acceptable value or below by adjusting the output of each of the inverters by controlling the equivalent output impedance by modifying both or either one of the output voltage feedback gain α or the output current feed forward gain β.
34 citations
TL;DR: The accuracy and validity of the model is validated, the sensor with best sensitivity is found, and the stability of the planar sensor is proven in the experiment.
Abstract: This paper investigates the detecting mechanism of planar electrode sensor in water pollutant detection. A system composed of electrodes, bulk media, and electrode–solution interface is built up, and the corresponding equivalent circuit containing bulk and interfacial impedances is established. The influence of each part is discussed while the impedance at interface is especially focused on. The impedance spectroscopy of the circuit is divided into three parts by the cutoff frequencies caused by interfacial and bulk impedances, and each of the frequency range can be used for the measurement of different physical quantities in water. The effect of electrode, especially the combination of interdigital and coils, is analyzed, and nine different sensors were designed and fabricated. Experiments validate the accuracy and validity of the model, and the sensor with best sensitivity is found. The stability of the planar sensor is proven in the experiment too.
34 citations
Patent•
05 Oct 1970TL;DR: In this article, a superconductive impedance element is connected in parallel with a conventional impedance element and is switched from essentially zero impedance to a high impedance during switching operation, thereby to connect the conventional impedance in the circuit to limit the current.
Abstract: A superconductive impedance element is connected in parallel with a conventional impedance element and is switched from essentially zero impedance to a high impedance during switching operation, thereby to connect the conventional impedance in the circuit to limit the current in the circuit. The impedances switched into the circuit are inductively associated with the superconductive element. A pilot super-conductive element is disclosed for the high accuracy switching of a main superconductive element.
34 citations
Patent•
02 Jan 2003TL;DR: In this article, a load-tracking (LT) network is proposed to track the changing output impedance of the cascode over an ultra wide frequency band, where the LT network is composed of a parallel combination of capacitive elements, inductive elements, and a resistive element.
Abstract: An ultra wide band (UWB) low noise amplifier (LNA) includes a common-gate (CG) amplifying element in cascode with a common-source (CS) amplifying element, and a load-tracking (LT) network to, at least in part, track a changing output impedance of the cascode helping to provide a substantially constant gain over an ultra wide frequency band of interest. The LT network may include of a parallel combination of a capacitive element, an inductive element, and a resistive element, which may be selected to, at least in part, track the changing output impedance of the cascode over an ultra wide frequency band. An initial common-gate stage may compensate for a capacitive input impedance of the cascode and may provide a substantially matched antenna input over the ultra wide frequency band. The amplifier may also include one or more resistor-based amplifying stages after the cascode.
34 citations