Abstract: A method of optimizing the frequency response of an interconnect system of the type which conveys high frequency signals between bond pads of separate integrated circuits (ICs) mounted on a printed circuit board (PCB) through inductive conductors, such as bond wires and package legs, and a trace on the surface of the PCB. To improve the interconnect system, capacitance is added to the trace and inductance is added to the conductors, with the added trace capacitance and conductor inductance being appropriately sized relative to one another and to various other interconnect system impedances to optimize the interconnect system impedance matching frequency response.

Abstract: A polyphase filter passes a desired frequency and attenuates an image frequency in many communication systems. The invention is an error correction circuit that compensates the polyphase filter for low open loop gain operational amplifiers. When multiple polyphase filters are used in communication circuits on a single integrated circuit (IC), the open loop gain of the operational amplifiers is limited by the IC's ability to dissipate power. The error correction circuit reduces the dependency of the polyphase filter performance on the low open loop gain of its operational amplifiers and hence, on temperature and IC process parameters.

Abstract: An impedance blocking filter circuit is provided for use in telecommunication systems for interconnecting between incoming telephone lines and customer's terminal equipment so as to unconditionally block impedances above 20 KHz due to the customer's terminal equipment from an ADSL network unit and/or home networking interface unit. The filter circuit includes first, second, and third inductors connected in series between a first input terminal and a first common point. A first resistor has its one end connected also to the first common point and its other end connected to a first output terminal. Fourth, fifth and sixth inductors are connected in series between a second input terminal and a second common point. A second resistor has its one end also connected to the second common point and its other end connected to a second output terminal. A capacitor has its ends connected across the first and second common points.

Abstract: A dielectric line has a conductor plate and dielectric strip on the side of a fixed portion and a dielectric line including a conductor plate and dielectric strip on the side of a moving portion. A directional coupler comprises the dielectric lines. On a dielectric plate of an array antenna portion a plurality of linear array antennas are formed and connected to a microstrip as a feed portion. By displacement of the moving portion, the feed point to the feed portion is changed and the feed phase to each linear array antenna and the feed power to each element antenna are changed. Thus, the direction of a beam is changed.

Abstract: A linear attenuation equalizer and a method for designing such an equalizer using the cable attenuation curve to determine the D.C. attenuation and the lower or first corner frequency. The D.C. attenuation and the lower corner frequency are used to fix the design. A curve fit technique is used to determine the cable attenuation parameter which fixes the D.C. attenuation of the equalizer. The lower corner frequency is set at between about 10% and less than about 50% of the data rate, and preferably at approximately 20% of the data rate.

Abstract: An article comprising a micro-machined, passively self-assembling inductor is disclosed. The inductor is fabricated using MEMS technology and advantageously utilizes materials compatible with CMOS such that inductor is monolithically integrable with a CMOS chip. The inductor includes passive self-assembly means by which the inductor loop is moved away from an underlying substrate, typically silicon, in the final steps of inductor assembly. Such passive self-assembly does not require separate actuation or monitoring steps.

Abstract: A CATV power inserter is presented allowing multiple power sourcing configurations while providing isolation between the RF signal and alternating current insertion ports. The power inserter achieves the variety of configurations by using a four point terminal block having uniform dimensions allowing simple connecting bars and fusing or current limiting options to be interchanged thereby increasing economy and performance.

Abstract: A low pass filter exhibiting low loss, low reflection, and Gaussian phase distortion characteristics at microwave and radio frequencies is provided. The low pass filter may comprise a negative feed forward network having a first directional coupler having a resonant frequency f.sub.0 and a second directional coupler having a resonant frequency f.sub.0, a through port of the first directional coupler being coupled to a through port of the second directional coupler, a coupled port of the first directional coupler being coupled to a coupled port of the second directional coupler, and an isolated port of the first directional coupler and an isolated port of the second directional coupler being terminated in matched loads. Additional embodiments employing multiple negative feed-forward networks are also disclosed.

Abstract: The filter circuit is a filter circuit having plural passbands including a first filter having a first passband, and a second filter having a second passband, with their inputs and outputs connected mutually so that these filters are connected in parallel. Inductor elements are connected in series to the terminal of the first filter to which the second filter is connected, and capacitor elements are connected in series to the terminal of the second filter to which the first filter is connected.

Abstract: The broadband microwave frequency shifter is an electro-optical device that accomplishes frequency shifting, or translation by the use of serrodyning or mixing techniques. A first optical signal is modulated with the radio frequency signal desired to be translated and processed to produce an upconverted lower sideband optical signal. A second optical signal is frequency shifted using an optical phase shifter utilizing serrodyning techniques or by offset phase locking it to another optical signal. When the frequency shifted optical signal is combined with the upconverted optical signal and converted to an output radio frequency signal thereby producing an output microwave signal that duplicates the input microwave signal in all aspects except that its center frequency has been shifted.

Abstract: This invention discloses a balancing circuit for providing a substantially fixed level of attenuation within a given return path frequency passband, while preventing noise related harmonics from distorting signal transmissions within the return path frequency passband. The balancing circuit includes coupling capacitors which are connected in series between input and output end nodes. A series connected inductor and capacitor pair is connected between each of the input and output end nodes and ground to form end sections. Another inductor is connected between the coupling capacitors and ground. A resistor is connected in parallel with the respective capacitor of each end section. The balancing circuit is placed in series at each subscriber port, and may be mounted on a printed circuit board and enclosed within a tubular housing with mating male and female "F" connections.

Abstract: In a telecommunications network, a method and apparatus for allocating channels include making signal quality measurements for channels that are in use or available for use and for channels that may become available for use. Spectral efficiency is enhanced by considering the exclusionary bandwidths associated with combiner filters tuned to currently allocated frequencies.

Abstract: A network interface for receiving both high speed signals and low speed signals includes a passive filter manufactured entirely from passive electronic elements. The filter filters the low speed signal when a low speed signal is received, and does not distort a high speed signal transmitted to an encoder/decoder device when a high speed signal is received.

Abstract: An active harmonic filter selectively sources current to or draws current from power lines. The active harmonic filter includes a controller which executes a predictor routine which predicts the current to be supplied to or drawn from the power line at a time t+.DELTA.t to reduce load induced phase differences between the line voltage and the line current. An integrating slow control routine integrates difference currents between actual line currents and desired line currents in equivalent segments of time in different cycles of the power line. The integrated differences may be combined with proportionally controlled difference currents to reduce or eliminate harmonic line currents. A current balancing routine enables the active harmonic filter to balance currents in two or more lines of a polyphase power line. The predictor, integrating slow control and current balancing routines, may be used singly or in combination to improve the condition of line currents on the power lines.

Abstract: An equalizing filter with an optimized frequency response and improved reliability and quality, for equalizing a reception signal so as to regain its original waveform. The equalizing filter comprises a low-pass filter and a high-frequency booster circuit. With its limited passband, the low-pass filter rejects the noise components contained in the signal being processed. The high-frequency booster circuit has such a frequency response that exhibits a stepwise gain increase at high frequencies. Those two elements, composed of reliable passive components, are coupled in series to provide a combined frequency response that is optimized for the design of highly sensitive optical receivers. As integral part of the high-frequency booster circuit, the equalizing filter employs an inductor made of a bonding wire.

Abstract: An electrical component assembly which includes a plurality of spaced capacitors, a pair of respective leads extending from each capacitor and a common encapsulant encapsulating the capacitors such that portions of each of the leads extend from the encapsulant and such that bobbins are formed between adjacent capacitors. Respective coils are then formed about each bobbin and connected to the capacitors.

Abstract: An active interphase reactor for twelve-pulse diode rectifiers is disclosed. The system draws near sinusoidal currents from a power utility. In one embodiment, a low kVA (0.02 P.sub.o (PU)) active current source injects a triangular current into an interphase reactor of a twelve-pulse diode rectifier. This modification results in near sinusoidal utility input currents with less than 1% THD. In alternative embodiments, a low kVA, 12-pulse system with an autotransformer arrangement (kVA rating of 0.18 P.sub.o (PU)) is implemented with the proposed active interface reactor. The resulting systems draw clean power from the utility and are suitable for powering larger kVA ac motor drive systems.

Abstract: A passive filter device for a capacitor in series with a substantially inductive transmission line of an electric transmission system is disclosed. The passive filter device comprises a double-loop RCL filter in parallel with the series capacitor. At power frequency, the filter device allows the power frequency current to pass through the series capacitor with minimum power losses. At sub-synchronous resonance frequencies, the passive filter device provides bypassing of the series capacitor with maximum selectivity of the RCL filter.

Abstract: An optimized electroless copper plating technique suitable for plating electroless copper upon ceramics.

Abstract: A circuit arrangement for igniting and operating a discharge lamp is provided withinput terminals for connecting a supply source, and a ground terminal, differential-mode and common-mode filters in which inductance and capacitance are incorporated,output terminals for connecting the discharge lamp, anda switch mode power supply connected to the input terminals and the output terminals by respective voltage conduction branches.The circuit arrangement is characterized in that the input terminals and output terminals are connected both to one another and to the ground terminal by respective capacitive filters, in that a bead is included in one of the voltage conduction branches, and in that further common-mode capacitance is present between the inductance and the switch mode power supply. The requirements formulated in both EN55022 and EN55015 can be complied with in this manner.

Abstract: A device (1) for correcting the amplitude/frequency characteristic of an input signal (FI), particularly from transmission cables (40), having a minimal frequency f1, a center frequency f0 and a maximal frequency f2, the input signal (FI) having an attenuation as a function of frequency characteristic that increases between f1 and f2, the correction device (1) supplying a corrected output signal (). The correction device includes two cascaded filters (41, 42), the first of the filters receiving the input signal (FI) and supplying a filtered signal (SFI) to the second of the filters, the second of the filters supplying the corrected output signal (). One of the filters is a band-stop filter (41) having a center frequency f3 less than or equal to f1, the other of the filters being a band-pass filter (42) having a center frequency f4 greater than or equal to f2. The center frequencies f3 and f4 satisfy the equation:f3.times.f4=f0.sup.

Abstract: A method and apparatus for filter enhancement in an electrical system (8) is provided. The electrical system (8) includes an input circuit (10) having a filter (14) and an output circuit (20) having a filter (24). An input conductive enclosure (12) and an output conductive enclosure (22) protect the electrical system (8) from field coupling between the input circuit (10) and the output circuit (20). A choke balun (26) is connected between the input circuit (10) and the output circuit (20) to also eliminate conductive coupling. The elimination of unwanted coupling enhances the performance of the electrical system (8) by achieving greater stopband attenuation.

Abstract: A band-pass filter device includes a band-pass filter having a characteristic for sufficiently passing signals belonging to a passing frequency band to be passed, a first trap circuit having a Q factor sufficiently higher than that of the BPF and attenuating signals belonging to a frequency band ranging frequencies higher than the passing frequency band, a second trap circuit for attenuating signals belonging to a frequency band ranging frequencies lower than the passing frequency band, a third trap circuit having a Q factor lower than that of the first trap circuit and attenuating an unnecessary component generated in the first trap circuit from the signal, a fourth trap circuit having a Q factor lower than that of the second trap circuit and attenuating an unnecessary component generated in the second trap circuit from the signal.

Abstract: A bandpass filter network having a first two pole filter and a second two pole filter provided in parallel to the first two pole filter. The first filter is optimally coupled while the second filter is extremely overcoupled. Moreover, the first filter and second filter are shifted 180.degree. out of phase with one another. This phase shift is preferably accomplished by a balun transformer. Alternatively, the 180.degree. phase shift may be accomplished by having the first and second filters utilizing different forms of coupling (i.e., one inductively coupled, the other capacitively coupled).

Abstract: A communication cable for connecting a computer main body with a monitor to display an image on the monitor and to reduce electromagnetic wave interference, includes a plurality of video signal lines for transmitting video signals and ground lines respectively corresponding to the plurality of the video signal lines, each of the plurality of the video signal lines including a filter including an inductive element which is inserted in series with respect to the video signal line and a capacitive element which is connected in parallel between the video signal line and the ground line corresponding to the video signal line wherein respective nodes between the plurality of the capacitive elements each of which is included in the filter of the video signal line and the ground lines corresponding to the plurality of the video signal lines are connected with a common line. Thus, electromagnetic wave interference can be removed without variation of the video signal level.

Abstract: An apparatus and method for reducing distortion currents present in an alternating current power system supplying power to a load which includes a passive filter and an active filter. In a first embodiment, the passive filter is operably connected to the power system across the load by a switching device. An active filter is then connected across the switching device and operated to draw a current equal to the current through the passive filter. The active filter and the passive filter are thereby connected in series across the load. The active filter is controlled to draw a fundamental frequency component and to provide distortion currents required by the load. In a second embodiment, the active filter is connected in parallel with a first circuit, the parallel combination of which is connected in series with a second circuit across the load.

Abstract: A reduced size three-terminal type capacitor for removing jamming signals from an electrical signal. The three-terminal type capacitor comprises a ceramic substrate with a first ground electrode layer formed on the ceramic substrate, and a first dielectric layer formed on the first ground electrode layer. On the first dielectric layer reaching at least from one end of the first dielectric layer to the other end is a signal electrode. A second dielectric layer is formed on the first dielectric layer to surround the signal electrode together with the first dielectric layer, and a second ground electrode layer is formed on the second dielectric layer together with the first ground electrode layer. The second ground electrode layer is electrically connected to the first ground electrode layer. The structure of this three-terminal capacitor is such that first and second conductive layers (i.e.

Abstract: A split-band device for transmitting and amplifying television signals between an input terminal and an output terminal which can each be coupled to a distribution cable having a characteristic impedance R.sub.0. The device comprises first and second parallel-arranged branches comprising, respectively, first and second amplifiers. The first branch has a high-pass first filter arranged between the input terminal and its first amplifier and the second branch has a low-pass second filter arranged between the input terminal and its second amplifier to select a second frequency range different from a first frequency range of the first amplifier.

Abstract: The relationship between the input and output of a signal transfer circuit, such as a tune circuit, a filter, a phase shifter, an amplifier, etc., is determined by the circuit response to the input signal. The value of the circuit response (R) is controlled by the value (V) of a control signal supplied thereto. According to the invention, the relationship between the latter values is approximated by a linear regression function based on a number of measured first pairs of response/control signal values and based on such regression function a transcoder determines control signal values for providing response values of the circuit in accordance with second pairs of response/control signal values.

Abstract: A method for determining the transmittance of a filter circuit adapted to transform the impulse response of a filter into a minimal phase response entails computing the theoretical frequency response of the filter circuit and the minimal phase frequency impulse response with a causality condition applied to the cepstrum of the minimal phase response, determining the theoretical transmittance as the inverse fast Fourier transform of the theoretical frequency response, estimating the transmittance of the filter circuit by truncation of the theoretical transmittance of which only a predetermined number of coefficients are retained and determining the minimal phase global response from a limited expansion of the cepstrum.

Abstract: A variable attenuation microwave attenuator includes input and output terminals, a high-pass filter having an electrical length of 90.degree. and transmitting signals with frequencies higher than a cut-off frequency, a first variable resistor connected between the input terminal and an input end of the high-pass filter, and a second variable resistor connected between an output end of the high-pass filter and the output terminal, wherein input signals applied to the input terminal are attenuated by the first and second variable resistors before and after the high-pass filter. Therefore, the variable attenuator can be a lumped parameter circuit, i.e., the high-pass filter including two inductors and a capacitor, without using a transmission line as in the prior art device, so that the size of the device is significantly reduced.

Abstract: A noise removing apparatus wherein a .pi. filter is constructed by a pair of feedthrough ceramic capacitors and a lead for connecting the feedthrough ceramic capacitors to each other to improve the radio wave trouble resistance of an electronic equipment and remove a shielding casing. Electrodes are formed on the both sides of a dielectric plate having a plurality of through holes by plating or the like, the electrode on one side is divided into plural ones in correspondence to the number of the through holes, resist portions are formed on the electrode on the other side so as to be in one-to-one correspondence to the through holes to provide a plurality of feedthrough ceramic capacitors, and an arbitrary pair of electrodes on one side are connected to each other through an inductive lead passing through the associated through holes, thereby to construct a .pi. filter.

Abstract: The object of this invention is to provide an electrical signal filter for improving electrical characteristics and reliability of the electrical signal filter for use in a cable television by protecting it from moisture. In an electrical signal filter having a filter portion provided inside a cylinder-shaped shield case, the filter portion includes a first filter circuit and a second filter circuit respectively mounted on circuit boards, and a shield member arranged between the first filter and the second filter. In the electrical signal filter, a moisture-proof material is applied to an entire surface of the filter portion and a contact area where the cylinder-shaped shield case containing the circuit boards and the filter portion therein contacts external components.

Abstract: A single-ended digital interface cable and a balanced digital interface cable having a source end and a load end for propagating audio frequency signals in a digital format is disclosed. Each of the cables comprises a fixed capacitor or a capacitor and switch network which is coupled at or near the load end of the cables for providing a fixed bandwidth or for use in selectively controlling the bandwidth of the cables and a series resistance at each end thereof to dampen ringing.

Abstract: A coupling network for coupling a signal at a frequency from a voltage source to a load. The voltage source has a source resistance. The load has a load resistance and a load reactance. The ratio of the load reactance to the load resistance greater than 100. The coupling network includes a reactive element and a delay circuit. The reactive element is arranged in series with the load to resonate with the load reactance at the frequency. The delay circuit is between the reactive element and the source, has a delay equivalent to a quarter wave length transmission line at the frequency and has a characteristic impedance equal to the square root of the product of the values of the load resistance and the source required resistance.

Abstract: A limiting filter has nonlinear signal limiting devices integrally connected to the filter structure so that as the power level of input signals increase the nonlinear signal limiting devices decrease their impedance in response thereto, detuning the filter. Filter isolation thus becomes a function of both frequency and input power.

Abstract: A first filter the group delay of which in the pass band contains a ripple is connected to a second filter so as to cancel the ripple. The second filter has a pass band at least within the pass band of the first filter. The gain of the second filter is reduced gradually from the frequency of the minimum attenuation into the lower and higher frequency regions and the group delay thereof is reduced gradually from the frequency of the minimum attenuation into the lower and higher frequency regions.

Abstract: An intermediate frequency filter for an intermediate frequency used in the receiver section of a digital radio communications apparatus is composed of an amplitude-flat ceramic filter incorporating two ceramic resonators, a buffer means and a single tuning circuit having the center frequency thereof within the bandwidth of the amplitude-flat ceramic filter, all being connected in series with each other. The center frequency of the single tuning circuit and Q are adjusted to approximate the amplitude characteristic of the intermediate frequency filter to that of TBT filter (0.4.ltoreq.parameter m.ltoreq.1.0).

Abstract: A line filter assembly adapted to be inserted in an electrical power supply circuit of various electronic appliances for avoiding an invasion and leakage of noise include first and second core members each having a pair of opposite arms connected together through a common bridge. Coils are formed on the arms of each of the core members in such a manner that directions of magnetic fluxes produced in the closed magnetic circuit as a result of flow of line currents counteract while the same coils are so arranged that the magnetic fluxes produced in the closed magnetic circuit as a result of the flow of the line currents are oriented in the same direction.

Abstract: An electronic device is suggested which comprises a signal emitting circuit part (1) and a signal processing circuit part (4), at least one line for supplying the signal processing circuit part (4) with operating current and/or at least one signal input line (6) and/or at least one signal output line being guided to the signal processing circuit part (4) from an external circuit. The device includes at least one filter circuit (7) which is connected to the signal processing circuit part (4) and inserted into the signal line (6). The filter circuit (7) comprises additional damping elements for the associated line (6) for damping interference voltage induced by of external high-frequency fields. The amplitude of the interference voltage is greater, preferably substantially greater, than a linear control range of circuit elements of the signal processing circuit part (4). Damping elements and filter circuits are monolithically integrated together with the signal processing circuit part (4).

Abstract: An RF circuit which may be for example a high pass filter, low pass filter, phase shifter, bandpass filter, termination network, bias network, or series or parallel resonance circuit includes at least one strip conductor coiled about a region and an outer or ring strip conductor disposed about a periphery of the at least one coiled strip conductor and coupled to said at least one coiled strip conductor through a dielectric. Parasitic capacitance between the coiled conductor and outer or ring conductor provide capacitor elements for the circuit.

Abstract: A tuned filter having an improved Q is disclosed in which two or more inductors are placed in parallel to increase the net Q relative to a single inductor of the same net inductance and/or two or more capacitors are placed in series to increase the net Q relative to a single capacitor of the same net capacitance to improve the Q of a tuned filter.

Abstract: A filter which includes: a plurality of filter elements. The filter elements are composed of magnetic beads and a magnetic compound is provided wherein the filter elements sealed therein. The magnetic beads may be arranged in a single column magnetic compound, may be formed of a cubic shape or may be arranged in a parallel column therein.

Abstract: An active filter suppresses harmonic current components flowing through a power supply, to which a compensation object load including a harmonic component source and a capacitive load is coupled. The active filter supplies a compensation current Ic in accordance with an output of a subtracter coupled to current transformers for detecting the load current I1 and the capacitive load current If, respectively. Thus, the compensation current Ic supplied from the active filter corresponds to and compensates only for the harmonic current components generated by the harmonic component source. The capacitive load current If is excluded from control operation. Thus, the positive feedback of the system is avoided, and stable control operation can be obtained.

Abstract: A line filter assembly adapted to be inserted in an electrical power supply circuit of various electronic appliances for avoiding an invasion and leakage of noise includes first and second core members each having a pair of opposite arms connected together through a common bridge. Coils are formed on the arms of each of the core members in such a manner that directions of magnetic fluxes produced in the closed magnetic circuit as a result of flow of line currents counteract while the same coils are so arranged that the magnetic fluxes produced in the closed magnetic circuit as a result of the flow of the line currents are oriented in the same direction.

Abstract: An electrical signal filter in which circuit provided with filter circuits are inserted into a cylinder-shaped shield case, has a first cavity portion having an inner case. The side of one end of the inner case has the circuit boards inserted, and the side of the other end thereof is provided with one of an input side connector and an output side connector. The electrical signal filter also has a second cavity portion having a second shield case having an outer case. The side of one end of the second shield case is provided with one of an output side connector and an input side connector.

Abstract: A tuned filter having an improved Q is disclosed in which two or more inductors are placed in parallel to increase the net Q relative to a single inductor of the same net inductance and/or two or more capacitors are placed in series to increase the net Q relative to a single capacitor of the same net capacitance to improve the Q of a tuned filter.

Abstract: A tunable bandpass filter system and filtering method wherein the bandwidth of a tunable bandpass filter is adjusted as a function of the fundamental frequency of an input signal. Either a constant bandwidth or a constant quality factor tunable bandpass filter may be used. The center frequency of the tunable bandpass filter is adjusted in direct proportion to the product of the fundamental frequency and the number of a selected harmonic thereof. In the case of a constant bandwidth filter the bandwidth is adjusted in direct proportion to the quotient of the fundamental frequency divided by a selected filter quality factor. In the case of a constant quality factor filter, the bandwidth is indirectly controlled by adjusting the center frequency while adjusting the quality factor in inverse proportion to the harmonic number. The output amplitude of the filter is measured to determine the amount of distortion in the input signal. The fundamental frequency may be determined by measuring the input signal.

Abstract: A signal input device having a mutual inductor formed by a coil connected with a capacitor for a grounding cable in series and a coil connected with a capacitor for a signal cable in series, and a compensating capacitor connected with the series circuit composed of the capacitor and the coil on the grounding cable in parallel. The compensating capacitor serves to prevent occurrence of a voltage on the grounding cable, and accordingly only regular signals received by an antenna are transmitted. The mutual inductor prevents resonance of inductance of a lead terminal of the compensating capacitor with capacitance of the compensating capacitor.

Abstract: A laminated LC element comprises a laminate including a plurality of bonded insulating layers, a first conductor including conductive elements which continuously extend around the insulating layers so as to form a coil having a predetermined number of turns; and a second conductor including second conductive elements which extend around the insulating layers, facing the first conductor via said insulating layers, and producing a capacitance with the first conductor. The LC element can eliminate firmly noises from external sources.