Abstract: A device includes a selection circuit that is configured to generate a bias level. The device also includes a combinational circuit coupled to the selection circuit. The combinational circuit is configured to generate a distortion correction factor used offset inter-symbol interference from a data stream on a distorted bit based on the bias level to generate a correction signal. The device additionally includes a latching element coupled to the combinational circuit and configured to receive the first correction signal.

Abstract: A dry-type electrical transformer includes a coil assembly having at least one winding wound into a plurality of concentric turns, at least one cooling sector defined between adjacent concentric turns, spacers positioned inside the cooling sector and spaced from each other to allow a plurality of air ducts each defined between two adjacent spacers, and at least one electrical shield positioned in the cooling sector and arranged to electrically shield the air ducts. At least one electrical shield is positioned in the cooling sector and arranged to electrically shield the air ducts. The electrical shield include a first end edge connected to the turn at the inner side of the cooling sector, a second end edge which is free and electrically insulated from the surrounding parts, and a central portion extending between the first and second end edges and is positioned at the outer side of the spacers.

Abstract: An electrical filter structure for forwarding an electrical signal from a first filter port to a second filter port in a frequency-selective manner includes a filter core structure having a working impedance, wherein the working impedance is different from a first characteristic port impedance of a first filter port, and also different from a second characteristic port impedance of a second filter port. The electrical filter structure also includes a first matching arrangement electrically coupled between the first filter port and the filter core structure and a second matching arrangement electrically coupled between the second filter port and the filter core structure.

Abstract: Methods for checking available bandwidth using forward error correction are provided, the methods comprising: identifying data to be transmitted; determining an amount of forward error correction data to be sent to a receiver; creating the forward error correction data based on corresponding data in the data to be transmitted; transmitting to the receiver the forward error correction data and the corresponding data in the data to be transmitted; determining an error level in at least one of the corresponding data and the forward error correction data; and when the error level is below a value, increasing the amount of bandwidth used in a transmission to the receiver of other data in the data to be transmitted over the amount of bandwidth used in the transmission to the receiver of the corresponding data and decreasing the amount of bandwidth used for forward error correction data in the transmission of the other data.

Abstract: A transceiver is provided for wireless communication. The transceiver can include a bias source, a transformer including a primary side and a secondary side, and a switching device. During a receive mode, the primary side of the transformer is configured to receive a first signal from a first port. During a transmission mode, the primary side is configured to transmit a second signal from a second port. The switching device is configured to couple the first port to the bias source during transmission of the second signal and to couple the second port to the bias source during receipt of the first signal. The bias source can be, for example, ground.

Abstract: Exemplary embodiments of the present disclosure provide a method and controller for damping multimode electromagnetic oscillations in electric power systems which interconnect a plurality of generators and consumers. The controller for damping such oscillations includes a phasor measurement unit (PMU) and a power oscillation damper (POD) controller. Each oscillating mode signal is damped and then superposed to derive a control signal. A feedback controller is used to feedback the control signal to a power flow control device in the power system.

Abstract: A chip comprises and operational section and an input/output section. The operational section includes a controller. The input/output (I/O) section is coupled to the operational section. The I/O section comprises a transformer and a switching device. The transformer includes a primary side connected to first and second I/O ports and a secondary side connected to the operational section. The switching device is coupled to the controller and between the first and second I/O ports and a bias port, such that, under control of the controller, the switching device connects one of the first and second I/O ports to the bias port.

Abstract: An RF coupling circuit including a transformer and a parallel AC-coupling capacitor can advantageously ameliorate substantial attenuation of a signal, prevent destabilization of any feedback loop, and simplify the circuit design process. The AC-coupling capacitor can act as an “averager”, i.e. both the input and output sides of coupling circuit represent capacitances equal to the average of the input and the output capacitances. Thus, the inductors for tuning them out can become equal, thereby allowing a symmetric (or near symmetric) transformer to be used in the RF coupling circuit. When tuned properly, the transformer plus AC-coupling capacitor can also advantageously provide better in-band gain as well as frequency selectivity than other conventional coupling circuits.

Abstract: Systems and methods for improved Variable Speed Drives having active inverters include an input filter for filtering common mode and differential mode currents. A three-phase inductor has three windings, each winding of the three-phase inductor having a center tap dividing each winding into a pair of inductor sections; and a three-phase input capacitor bank connected in a wye configuration to the three center taps at one end, and to a common point at the opposite end. The three-phase input capacitor bank provides a short circuit for frequencies above a predetermined fundamental frequency for shunting such frequencies through the three phase capacitor bank, while passing the predetermined fundamental frequency to an input AC power source.

Abstract: A dynamic harmonic filter for an AC power system comprising at least one voltage source (V) and at least one load. The harmonic filter comprises a current sensing or voltage injection transformer (T1) connected in series with the voltage source and the load with one end of the primary (P1) of the current sensing or voltage injection transformer connected to the voltage source and the other end of the primary of the current sensing or voltage injection transformer connected to the load. The harmonic filter further comprises a parallel resonant LC circuit (L1C1) tuned to the fundamental frequency of the power system. One end of the secondary (S2) of the current injection of the voltage sensing transformer is connected to one junction of the parallel resonant LC circuit and the other end of the secondary of the current injection or voltage sensing transformer is connected to the other junction of the parallel resonant LC circuit through the secondary (S1) of the current sensing or voltage injection transformer.

Abstract: The electronic apparatus comprises a display portion and a quartz crystal oscillator at least, and said electronic apparatus comprises at least two quartz crystal oscillators. Also, each of two quartz crystal oscillators of the at least two oscillators comprises a quartz crystal oscillating circuit having an amplification circuit and a feedback circuit. The feedback circuit is constructed by a flexural mode, quartz crystal tuning fork resonator or a width-extensional mode quartz crystal resonator or a thickness shear mode quartz crystal resonator and for example, the quartz crystal tuning fork resonator comprising tuning fork tines and tuning fork base that are formed integrally, is shown with novel shape and electrode construction. Also, the quartz crystal tuning fork resonator, capable of vibrating in a fundamental mode and having a high frequency stability can be provided with a small series resistance and a high quality factor, even when the tuning fork resonator is miniaturized.

Abstract: An apparatus for reducing influence by selected signal components in a communication link includes a first signal line conveying a first communication signal including a desired signal component and at least one undesired signal component; a second signal line conveying a second communication signal substantially including at least the at least one undesired signal component; a signal treating unit coupled with the second signal line for affecting at least one parameter associated with the second communication signal to present a modified second communication signal at a first output locus coupled for combining the modified second communication signal with the first communication signal to present an improved communication signal at a second output locus. The at least one undesired signal component affects the improved communication signal less than the at least one undesired signal component affects the first communication signal.

Abstract: A tunable electrical filter constructed pursuant to the teachings of the present invention includes: (a) a plurality of resonator units coupled between an input locus and an output locus; and (b) a plurality of tunable dielectric varactor units; respective individual varactor units of the plurality of varactor units being coupled between respective pairs of the plurality of resonator units, coupled between the plurality of resonator units and the input locus, and coupled between the plurality of resonator units and the output locus.

Abstract: A method of balancing the bandwidth of a dual-mode filter, consisting of a ring resonator produced by microstrip technology, removes strip material in one or more places on the ring resonator where the first of the two modes of the ring resonator has a maximum current intensity, and in one or more additional places on the ring resonator, where the second mode has a maximum current intensity.

Abstract: A calibration circuit adjusts a differential output voltage from a line driver circuit when the differential output voltage falls outside a specified tolerance range. The calibration circuit includes a sample and hold circuit which samples the differential output voltage and holds a representative signal. A comparator compares the held signal with a reference voltage signal. When the held signal is greater than the reference voltage signal the comparator outputs a LOW signal and when the held signal is less than the reference voltage signal the comparator outputs a HIGH signal. The comparator output signal is stored in a memory circuit of a control logic. The control logic instructs an up/down counter to increment when the comparator output is LOW and to decrement when the comparator output is HIGH. A calibration current source sinks a unit of calibration current when the comparator output is LOW and sources a unit of calibration current when the comparator output is HIGH.

Abstract: A double super-heterodyne receiver has a high-frequency input circuit that includes a high-frequency amplifying device, a low-pass filter and a high-pass filter used for obtaining bandpass characteristics for the receiving band. A switching device for changing the cut-off frequency of, at least, the low-pass filter is further provided for the high-frequency input circuit. The switching device is controlled to be on or off in response to the receiving frequency, thereby changing the passband of the high-frequency input circuit. Image disturbance characteristics can thus be improved.

Abstract: A transmission line resonator is disclosed which has a resonance frequency that is electrically controllable by control voltage. A reactive circuit is coupled in parallel between two coupling points on the transmission line resonator. The reactive value of the reactive circuit is changed by the control voltage. The reactive circuit can be inductive or capacitive. The control voltage can switch the reactive circuit in parallel with a part of the transmission line resonator between the coupling points, or can control the capacitance value of a capacitance diode disposed in parallel with a part of the transmission line resonator between the coupling points.

Abstract: A bandpass filter is presented which is constructed so that bandwidth of the bandpass filter may be varied without varying gain from an input signal to an output signal when the input signal is at a center frequency. A crystal resonator is connected in series with a compensation resistance, and a variable resistance. Ignoring shunt capacitance, the crystal resonator may be modelled by a capacitance, an inductance and a loss resistance coupled in series. The compensation resistance is chosen so that the voltage drop across the compensation resistance is equal to the voltage drop across the loss resistance. A transformer having a primary coil, a secondary coil, and a 1:1 turn ratio between the two coils is included in the circuit. The primary coil is coupled in parallel with the compensation resistance. The output signal appears at an output of the secondary coil.

Abstract: A tunable coupling network for a frequency multiplier stage providing a passband for a desired harmonic of a fundamental frequency and rejection notches for undesired harmonic frequencies. The passband of the network can be tuned by changing the value of at least one circuit element to track the desired harmonic of the fundamental frequency over a range of fundamental frequencies. In so doing, the rejection notches also move so that they maintain fixed ratios with respect to the passband frequency as the passband moves. In one embodiment the network comprises first and second tunable circuits each including a variable reactive element. The first resonant circuit includes a variable capacitor and two fixed inductors. The second resonant circuit includes a variable inductor and two fixed capacitors. The two resonant circuits are coupled by an interstage coupling capacitor.

Abstract: A circuit having a variable input impedance which is controlled by application of a direct current input signal. The variable impedance circuit comprises a pair of capacitors coupled in series with a pair of diodes. The diodes are rendered conductive in response to the direct current control signal to substantially short the two capacitors in series with one another across the input terminals of the circuit. With no direct control signal being applied to the circuit the diodes are non-conductive which substantially disconnects the capacitors from appearing across the inputs of the circuit. Hence, the reactance component of the input impedance of the circuit is varied in response to the direct control signal.

Abstract: In modern communication systems, it has become important to provide filters, and in particular bandpass filters, which can provide substantially uniform group delay across the bandwidth of the filter while still achieving good amplitude response. In this regard, it is particularly desirable to substantially reduce the large variations in the phase characteristics found in conventional bandpass filters at the nominal band edge of the filter. To accomplish this, a filter is provided having at least one pair of lattice arms coupled in parallel to one another between the input and output of the filter. Each of the lattice arms includes a plurality of resonant LC resonators, each of the resonators having a different resonant frequency than the center frequency of the filter. In particular, within the bandwidth of the filter, the exponential damping coefficients for the resonators in each arm are set to decay at the same rate. This desired decay can be accomplished by exponential sizing of the components.

Abstract: A two terminal electronic filter network is provided for connection across TV antenna input terminals to reduce interference from noncommercial FM radio stations operating within a frequency band near the TV channel 6 frequency band. The two terminal electronic filter circuit which exhibits a rapid change of reactance for changes in frequency, and having a resonant frequency provides sufficient FM signal rejection without significant attenuation of any VHF channel by the provision of a highly reactive network tuned below the resonant frequency of the filter network as a whole.

Abstract: A nonlinear adaptive filter for improving the signal-to-noise ratio of video signals generated from images of features under analysis typically includes filtering components for attenuating low amplitude video noise excursions while passing high amplitude video signal excursions substantially without attenuation. Attenuation of the noise is provided by electrical circuitry operating as a function of the voltage input. In general, the electrical circuitry has a predetermined relationship to the value of the video signal and its noise characteristic.