Abstract: A wireline bridge tap device and an associated signal processing mechanism are capable of successfully extracting and recovering the respective signalling components of a full-duplex wireline digital data link without having to disturb the link during its use (e.g. as by interrupting service to sever the link in order to install a line coupling device, such as a modem or attenuator pad to signal monitoring equipment). The full-duplex wireline bridge device comprises a signal characteristic monitoring device that is capable of monitoring the link and providing respective output signals representative of the respective unidirectional signal components being transmitted simultaneously in opposite directions along the link. A directional signal separator, comprised of a voltage probe and a current probe, each of which can be coupled to the link without severing the link or otherwise disrupting ongoing communications, couples the signal characteristic monitoring device to the link.

Abstract: A plurality of inductors and a plurality of capacitors are formed as conductor patterns (3-1 to 3-4, to 4-8, 5) on dielectric layers (1-1 to 1-6) constituting a multi-layer wiring board. A set of circuit elements (inductors and capacitors) required to have the same inductance or capacitance value are formed on the common layers of the multi-layer wiring board. Thus, the circuit elements required to have the same value in the multi-layer wiring board can be manufactured under the same condition (the baking condition for example), so that the variations of the elements can be reduced.

Abstract: A lumped impedance transforming directional coupler including a first reactive element, a second reactive element coupled to the first reactive element at a first port, a third reactive element coupled to the second reactive element at a second port, a fourth reactive element coupled to the first reactive element at a third port and to the first reactive element at a fourth port, and the first, the second, the third, and the fourth ports each coupled through a first, a second, a third, and a fourth capacitor, respectively, to electrical ground, the reactive elements and the capacitors providing impedance transformation. Alternate embodiments include a lumped element directional coupler arising from a distributed impedance transforming directional couplers with a pair of transmission lines one-fourth of a wavelength of a center operating frequency in length, and a second pair of transmission lines three-fourths of that wavelength in length.

Abstract: A CM type directional coupler comprises a body having a dielectric layer, an annular magnet buried in the dielectric layer, a pair of transmission lines juxtaposed with a predetermined spacing between them in a magnetic area enclosed by the magnetic ring in the dielectric layer, and lead terminals extending from opposite ends of each of the transmission lines to outside of the dielectric layer, and all these elements are formed integrally with each other to provide a single device. Therefore, a large coupling factor and directivity are ensured, and the coupler can be designed very compact. This directional coupler can be manufactured with a highly improved yield and mass-producibility, so it is very suitably usable as a power detector in a portable telephone.

Abstract: A microstrip directional coupler which employs closed form solutions for compensating capacitance or inductance and odd mode characteristic impedance necessary to realize high directivity or match in microstrip directional couplers valid for tight and loosely-coupled sections. A microwave monolithic integrated circuit (MMIC) directional coupler with single capacitive or inductive compensation derives from a mathematical analysis using symmetry and reflection and transmission coefficients' equivalency. Closed form solutions for the compensating capacitance or inductance and a new odd mode characteristic impedance are generated. The results are implemented in single antisymmetric inductive and antisymmetric and symmetric capactive compensated versions.

Abstract: A four-port wide-band branch line coupler which distributes, to two output ports and over a wide bandwidth, a signal that is fed into an input port at any constant ratio with a phase difference of 90.degree., so that no power emanates from an isolated port. If a signal is fed into the isolated port, this power is also distributed to both output ports, so that no power emanates from the input port. The coupler has two identical rings consisting of quarter-wave length line sections that are connected by two half-wave length line sections and are connected, by series circuits made of half-wave length line sections with individual branch circuits connected in parallel to them, to the four ports. The circuit can be dimensioned for construction in microstrip technology or coaxial cable technology. Further, the circuit can be made of concentrated elements so that it can be used in microwave monolithic integrated circuits.

Abstract: A single constant voltage power supply concurrently supplies a plurality of independent loads each with an independently selectable constant current load without interaction between the loads (currents) by employing a plurality of parallel connected circuits of electrical lengths equal to (2n-1)90.degree. each connected between the constant voltage source and a different one of said loads.

Abstract: A directional filter is provided implemented with passive lumped elements in several embodiments from a general 18-element network, to an intermediate ten-element embodiment and a simple two-element filter each with features and advantages depending on the application. In general, a directional filter with lumped elements requires less physical area with similar performance characteristics as conventional transmission lines which is desirable in technologies such as MMIC.

Abstract: A low frequency multi-port signal coupler employing hybrid transformer coupling circuitry for intercoupling from a main communication line to output taps. In one embodiment, the coupler has two tap ports interconnected by two core transformers, each having a termination resistor associated therewith. In another embodiment of the invention, there are four tap ports interconnected by three core transformers and a shunted inductor, and having three termination resistors and a split-matching isolation resistor associated with the output taps. An impedance matching resistance is provided at the input and output of the two port embodiment.

Abstract: An RF coupling device is formed on a hybrid printed circuit which avoids discrete capacitors or resistors. The substrate is formed of refractory dielectric sheet, such as alumina or another ceramic. A printed conductor is printed on the front surface of the substrate, and has one or more broadened portions formed on it as capacitor plates. One or more printed resistors are in contact with the printed conductor. A ground pad is printed in a predetermined pattern onto a portion of the reverse surface of the substrate at selected locations. The ground pad has one or more portions that are in registry with the capacitor plates and serve as grounded plates for the capacitors. One or more inductors can be printed onto the substrate in a meander pattern and in contact with the remainder of the printed conductor. The printed circuit receives one or more RF transformers whose leads can be soldered to the printed circuit.

Abstract: A microstrip capacitively-compensated directional coupler with improved directivity and decreased coupling length. The directional coupler of the invention includes a primary transmission line, having a first port and a second port and a secondary transmission line electromagnetically coupled to the first line. The secondary transmission line has a third port and a fourth port. The invention also calls for a first reactive coupling network disposed between the first port and the third port, and a second reactive coupling network disposed between the second port and the fourth port. Those reactive couplings improve the directivity of the coupler and foreshorten its coupling length. The invention also calls for a phase-shifting line for shifting the phase of the coupled signal. The phase-shifting line further foreshortens the required coupling length for the coupler.

Abstract: A coupler for a balanced two wire data transmission line includes input and output ports as well as a forward coupled port and a reflected coupled port. The coupler is constructed of passive components including transformers and resistors to provide at the forward coupled port a signal proportional to the signal transmitted from a source to a load and provide at the reflected coupled port a signal proportional to the magnitude of the signal reflected from the load due to mismatch.

Abstract: A low frequency multi-port signal coupler employing hybrid transformer coupling circuitry for intercoupling from a main communication line to output taps. In one embodiment, the coupler has two tap ports interconnected by two core transformers, each having a termination resistor associated therewith. In another embodiment of the invention, there are four tap ports interconnected by a single core transformer having a split-matching isolation resistor associated with each output tap, and a pair of termination resistors at the input and output of the primary winding. An impedance matching inductance is provided at the input in both embodiments.

Abstract: A wideband active quadrature 90 degree hybrid for increased bandwidths with low power losses and the capability to have gain. The 90 degree hybrid can be incorporated in small areas for MMIC (monolithic microwave integrated circuits) circuitry in the low microwave frequencies. The 90 degree hybrid comprises a plurality of 90 degree phase shift means, each preceded by an input amplifier. Each of the 90 degree differential phase shift means comprises a high pass and a low pass filter. The low pass filter outputs are added together and amplified. The high pass filter outputs are also added together and amplified. The resultant amplified signals are output with a phase differential of 90 degrees. The amplifiers supply gain which is lost in the 90 degree phase shifting.

Abstract: A 90 degree hybrid is contemplated having three parallel signal paths, one of the signal paths is a central signal path which provides direct impedence to ground. The other two signal paths are capacitively coupled to the central signal path to provide a second impedence. Each signal path incorporates at least one inductor coupled in series along each of the signal paths. The signal paths are capacitively coupled to each other at each end of the inductors. To increase the bandwidth, additional hybrids are coupled in series, with each hybrid forming a section of the broadband hybrid.

Abstract: A thin film power coupler, in particular, a 3 dB and 90 degree power divider, is fabricated of lumped circuit elements. The main characteristics of the coupler is in having achieved the coupled inductances by mutual induction. Such an achievement has been obtained with 2 microstrip lines facing each other and wrapped in a square shaped spiral. Another important characteristic of the power coupler is the presence of a capacitor in the circuit which joins the two branches of the coupler, with sufficient tolerance to obtain the wanted coupling and to recover possible tolerances incurred by manufacturing the thin film inductors.

Abstract: A directional coupler transformer insensitive to data bus termination failures, includes a ferrite toroid core about which first through fourth windings are wound, the first and second windings being for connection in series with each conductor, respectively, of a data bus for sensing or generating data signal current, the third winding being connected in parallel with the data bus conductors for sensing or generating data signal voltage, and a fourth winding inductively coupled to the other three windings for either coupling data signals traveling in one direction from the data bus to a receiving unit, or coupling data signals from a transmitting unit to the data bus for transmission along the data bus in a given direction.

Abstract: A high frequency directional coupler having improved intermodulation distortion performance is disclosed. The coupler includes input, output, reflected, and incident ports, and current and voltage transformers. The current transformer includes at least one primary winding connected between the inlet and outlet ports and at least one secondary winding coupled with the primary winding and connected between the reflected port and ground. The voltage transformer includes a plurality of series-connected primary windings connected between the reflected and incident ports, and a plurality of series-connected secondary windings coupled with said voltage transformer primary windings, respectively, and connected between the input port and ground. Shunt capacitors connected with the input, output, reflected and incident ports increase the bandwidth of the coupler.

Abstract: A variable amplitude delay equalizer network comprising generally a 90.degree. hybrid matrix consisting of toroidal transformer and two capacitors and having an input, an output and two reference ports. A reactive network at the first reference port forms a network which allows input energy to be shifted in phase and returned to the hybrid, thus providing envelope delay correction. An amplitude corrective network at the second port permits adjustment of the amplitude response essentially independent of envelope delay adjustment.

Abstract: A directional coupler with a first and second transformer, having their primary windings connected in series, provides a sample of the current flow through the series connected primary windings. A third transformer provides a voltage sample of the voltage that results from the current flow through the primary windings of the first and second transformers. The voltage sample and the current sample are vectorially combined by a vector adder to obtain a first signal that is representative of the reflected power components of the current and voltage samples and also to provide a second signal that is representative of the forward power components of the current and voltage samples.

Abstract: A broadband radio frequency signal are in the range between about 5 and 400 MHz and a single phase 60 Hz AC power signal are transmitted through a cable transmission line of a cable television system. Amplifiers are powered by the 60 Hz AC signal. The amplifiers are operable as repeater stations that transmit the radio frequency (RF) signal. An RF choke connected to the transmission line separates the 60 Hz AC signal from the broadband 5 to 400 MHz signal. The RF choke includes a conductor of a preselected gauge formed in a coil having a preselected number of turns wound around a ferrite coil form. A ferrite bead is in series with the coil on a selected turn of the coil. The ferrite bead displays an RF series resistance or impedance to the inductance of the coil and reduces the series resonance of the coil. A resistor is connected in parallel to a selected turn of the coil at the opposite end of the coil and functions as a shunt.

Abstract: A directional coupler for sampling energy traversing a CATV system of the type wherein wide band television signals are extracted from a coaxial transmission line situated at points located at varying distances from the line amplifier. The coupler includes a voltage sensing transformer in shunt with the center and outer conductors of the cable and a current sensing transformer in series with the center conductor. The transformers are wound to provide the coupler with a relatively low tap value. Windings in the shunt transformer are used to internally boost the impedance at the input to the series transformer to maximize return losses and directivity.

Abstract: An improvement in directivity and isolation of a quarter wave microstrip directional coupler is achieved with the addition of a single capacitor placed across the directive port of the coupler.