Abstract: A variable ratio power divider/combiner includes first and second resonant circuits connected between the input port and the two output ports in the divider configuration. The signals appear at an output port of the divider as determined by the resonant condition of the resonant circuits. The resonance condition is controlled by a control signal that varies a capacitance in the resonant circuit.

Abstract: An asymmetrical coupling circuit for use in a network analyzer is provided with a pair of couplers coupled to the input and output ports of a device under test (DUT) for improving the dynamic range of forward and reverse transmission measurements. The through-arms of the couplers are used to connect the input and output ports of the DUT to the reference signal source and measuring circuit to thereby eliminate the attenuation caused by feeding a signal through the coupling arm of the coupler as occurs in symmetrical coupler arrangements.

Abstract: A tap device for use in broadband communications systems includes a circuit board mounted on a cover plate assembly which is removably connected to a base housing. The circuit board includes an RF signal coupling element and an RF signal splitting element. The output of the RF signal coupling element and the input to the RF signal splitting element are each connected to a separate female receptacle positioned on the circuit board. The female receptacles are designed to receive an intermediate circuit which, when inserted into the female receptacles, is electrically connected between the RF signal coupling element output and the RF signal splitting element input. The intermediate circuit may consist of a short circuit feedthrough, or a plug-in fixed or variable degree attenuator.

Abstract: A noncontact switch couples power from A and B radio frequency sources to a load and an antenna in three modes. Mode I couples the A source to the antenna and the B source to the load; Mode III is B to antenna and A to load, and Mode II couples both A and B sources to the antenna. The structure includes a first 3dB, 90.degree. coupler coupled to the sources and a second 3db, 90.degree. coupler coupled to the load and the antenna. A third 3dB, 90.degree. coupler is coupled in a first path between the first and second couplers. A pair of reflective terminations coupled to ports of the third coupler are mechanically controllable to one of three phase-shift conditions; 0.degree. for mode I, 90.degree. for mode II and 180.degree. for mode III. A fixed phase shifter couples the first and second 3dB, 90.degree. couplers by a second path. Each reflective phase shifter is a coaxial circuit including the parallel combination of first and second series inductance-capacitance circuits.

Abstract: An R.F. switch includes a directional coupler with a main line and a quarter wavelength coupled arm. One end of the main line is connected to a first input port and the other end is connected to a first output port. The coupled arm is selectibly terminated at one end in either its characteristic impedance or a short. A PIN diode controls the termination. The second end of the coupled arm is connected to a second input port. A PIN diode switch is connected between the second end of the coupled arm and a second output port. In a first position, signals present at the input ports are combined and appear at the first output port. The directional coupler provides isolation such that the signal at the second input port is not coupled to the first input port. In the second position, the signal at the second input port is disconnected from the first output port and only connected to the second output port.

Abstract: A hybrid power combiner and controller device is disclosed. The device includes a multiple branch hybrid network, with PIN diodes employed to selectively short circuit the midpoints of the branch lines to ground. With the PIN diodes biased to the open circuit condition, the device behaves as a conventional hybrid combiner, for example, to combine the power produced by two input sources at the device output port. With the PIN diodes biased to the conductive condition, thereby shorting the branch line midpoints to ground, the device behaves as a matched multiple stub filter tuned to the desired band. Substantially all the power provided by one input power source will be provided at the device output in this case.

Abstract: A dielectric rotary coupler for electromagnetic waves of the microwave frequency region structured of a substantially ring-shaped rotary member and a stationary member, each member being formed of a dielectric waveguide, or line, having a rectangular cross-section. The rotary line and the stationary line are arranged to face each other with a predetermined space therebetween along a coupling length, through which a microwave, for example, a carrier microwave FM-modulated by a signal reproduced by a rotary head of a VTR, is coupled from the rotary line to the stationary line, or vice versa.

Abstract: A gallium arsenide isolator has a common gate FET for amplifying a microw signal, the common gate FET being connected to a common drain FET for transmitting the microwave signal and for isolating the common gate FET from signals travelling in a direction opposite to the microwave signal. One or more L-C networks are connected at one end between the input and output of the isolator and at the other end to ground. The circulator includes three arms each having a gallium arsenide isolator. Each of the arms is coupled to another one of the arms by means of a four port coupler which permits transmission of a signal from one port to a second diagonally opposite port, the third port receiving a fixed fraction of the power and the fourth port receiving effectively no power.

Abstract: A system for providing a quadrature hybrid with a wide bandwidth and an extremely low amplitude imbalance. This system incorporates conventional quadrature hybrids as components and provide a system quadrature hybrid having a larger bandwidth and a far lower amplitude imbalance than that of any of the component quadrature hybrids. Typically, the system bandwidth improvement over that of the component hybrids is 60 percent, while the improvement in the imbalance is 6 to 1. These improvements are achieved using a system network consisting fundamentally of three conventional hybrids, a reversing divider and an in-phase divider, all of which are readily available components. This system provides a significant improvement over more complicated quadrature hybrid designs where filter networks are required to obtain wide bandwidth. The widest bandwidth components now abailable, including those using filter networks, can be incorporated in the present invention to provide an even wider system bandwidth.

Abstract: A six-port reflectometer has first and second directional couplers, a first waveguide and a third directional coupler providing a series connection from a source to a test device. The first coupler is connected to two detectors. The second coupler is connected to a third detector and to a fourth waveguide having two ports connected via a waveguide and a further port connected to an absorber. The third coupler is connected to a detector and a reflector. The second waveguide and the reflector receive radiation coupled by the second and third couplers respectively. The third and fourth couplers provide equivalent transmission paths. Equal path lengths are traversed by signals leaving the second coupler and returning to it from the reflector and the fourth coupler respectively. With broad-band couplers and waveguides, this arrangement gives broad-band performance.

Abstract: A passive, single cable, local area network system includes two directional couplers at each cable tap to provide bi-directional communications for each communications terminal. Each coupler introduces some amount of signal power loss through the cable such that the signal power level between any two communicating terminals depends on the cable distance between them, measured in number of intervening cable taps. Selectable attenuators are provided between the directional couplers and the corresponding communications terminals to virtually equalize the signal power level between any two terminals. The value of attenuation is selected according to a relationship including the number of cable taps in the system, the signal power loss along the cable introduced by each directional coupler, and the ordinal number of the corresponding terminal from the cable termination in the direction toward which the terminal's directional coupler communicates.

Abstract: Isolation is provided to two signal sources whose output signals are combined by the use of an outphasing technique. A first divider divides the signal from a first signal source into two signals and a second divider divides the signal from the second signal source into two additional signals. A first output of the first divider and a first output of the second divider are connected together by an attenuator and delay line which is used to cancel the leakage across a hybrid combiner. A second output of the first divider and second divider is applied to the hybrid combiner where the two signals are combined to obtain a combination signal that has enhanced isolation.

Abstract: A television broadcast transmitter includes two power amplifiers or transmitters, a dummy load and an antenna. A noncontacting switching arrangement includes directional couplers or hybrids operated as controllable phase-shifters under the control of pairs of variable reactive terminations. Signals arriving at the antenna or load port by two paths combine in-phase to couple signal to that port, or combine out-of-phase to cancel signal. If the out-of-phase condition is inaccurate, cancellation may be incomplete, resulting in crosstalk. To avoid the need for accurate positioners to position the variable reactive termination at the position providing the desired phase-shift, a particular structure of the reactive termination is used. The reactive termination is a short-circuited coaxial line with an axial gap in the center conductor at a position less than one quarter operating frequency wavelength from the short circuit.

Abstract: A network having a plurality of network ports includes a plurality of substantially identical independent components, each one thereof having a plurality of ports, the degree of coupling among the ports of each component being characterized by a predetermined scattering coefficient matrix. A plurality of feed networks is included, each one having: a first port corresponding to one of the plurality of network ports; and, a plurality of second ports each one being coupled to a corresponding one of the plurality of ports of each one of the plurality of components, the degree of coupling among the first port and the plurality of second ports of each of the feed networks being characterized by a predetermined scattering coefficient matrix. The plurality of feed networks and the coupling thereof to the components characterize the network with a scattering coefficient matrix, relating the coupling among the network ports, different from the scattering coefficient matrix characterizing each one of the components.

Abstract: A six-port reflectometer includes first, second and third forward directional couplers to transmit power from a source for reflection at a measurement port. The couplers also divert incident and reflected wave samples for subsequent measurements. A fourth forward directional coupler receives samples of incident and reflected waves from the second coupler, the reflected waves being received directly and the incident waves via a waveguide appropriate to equalize wave path lengths. The first coupler is connected to a matched load and the third coupler to a short circuit. The first coupler may be a 6 dB device and the second, third and fourth couplers 3 dB devices. Power detectors are connected to the first, third and fourth couplers. The reflectometer has the band-width of its components.

Abstract: A microwave coupler for coupling microwave energy from a first waveguide to a second waveguide disposed side by side along a propagation length includes a common coupling means, and specifically, orifices along the propagation length wherein the coupling orifices are sized to promote coupling of a favored field mode of electromagnetic energy according to a Bessel function distribution of energy along the length of the waveguide. The Bessel function distribution provides for wideband, low-loss coupling of the favored field mode and maximal isolation from non-favored field modes. The invention is particularly useful for extracting a type TE.sub.21 circular mode signal from a signal containing TE.sub.11 and TE.sub.21 circular modes wherein the TE.sub.21 mode signals are used for generating elevational and azimuthal tracking signals.

Abstract: A system for amplifying R.F. signals with a selectable substantially constant phase at the output port (OP) relative to the input port (IP) comprises a phase shifter (PS) and an amplifier (AMP), a phase discriminator (PD) and a video processor (VP) which controls the phase shifter (PS) in accordance with the output of the phase discriminator (PD) and a phase selection signal (SEL). This signal (SEL) selects a bias voltage to cause the phase shifter to introduce a phase shift such that the relative phase at the output port is approximately equal to a desired value and also to select a monotonically varying error function which is derived from the phase discriminator and which is representative of the difference between the desired value and the actual value of the relative phase.

Abstract: The signal to be amplified is applied to a quadrature coupler which splits the signal equally to provide two output signals in phase quadrature. The quadrature signals are amplified equally, which generates a second harmonic in each of the signals 180 degrees out of phase. The amplified signals are combined in an in-phase power divider to provide a single amplified output signal wherein the out-of-phase second harmonic signals cancel.

Abstract: A lossless and matched dual mode network (10) in which the maximum voltage amplitudes (a, b, and c, respectively) appearing at three output ports (11, 12, 13), are preselected and are arbitrary subject only to the constraint that the sum of the squares of any two elements of the set (a, b, c) must be equal to or greater than the square of the third element of this set. The set of complex voltages (A, B, and C, respectively) appearing at the three output ports (11, 12, 13) when an input signal is applied to one of the input ports (1 or 2) is conjugate with the set of output voltages (AA, BB, and CC, respectively) appearing at the three output ports (11, 12, 13) when an input signal is applied to the other input port, which is isolated from the initially selected input port (1 or 2). The network (10), which may be used as a feed network in an antenna (25) system, e.g., as an even/odd mode network, comprises three 90.degree. couplers (31, 32, 33 ) and three phase shifters (41, 42, 43).

Abstract: An adjustable two-port microwave network having digitally controlled switches which enable the network to be set to a plurality reflection and transmission coefficients. The network facilitates the collection of a plurality of measurements which are necessary to characterize a non-linear device. An embodiment of the network is constructed using a 3dB directional coupler feeding two identical power divider networks each comprising two cascaded directional couplers. One divider network is connected directly to the coupled port of the 3dB directional coupler and the other divider network is connected through a phase shifter to the output port of the 3dB directional coupler. The non-linear device to be characterized is connected to the input port of the 3dB directional coupler and for this application, the isolated port is terminated in its characteristic impedance.

Abstract: A reconfigurable dual mode network (10) in which the maximum voltage amplitudes (a, b, and c, respectively) appearing at three output ports (11, 12, 13), are preselected, reconfigurable, and arbitrary subject only to the constraint that the sum of the squares of any two elements of the set (a, b, c) must be equal to or greater than the square of the third element of this set. The set of complex voltages (A, B, and C, respectively) appearing at the three output ports (11, 12, 13) when an input signal is applied to one of the input ports (1 or 2) is conjugate with the set of output voltages (AA, BB, and CC, respectively) appearing at the three output ports (11, 12, 13) when an input signal is applied to the other input port, which is isolated from the initially selected input port (1 or 2). The lossless and matched network (10), which may be used as a feed network in an antenna (25) system, e.g.

Abstract: An RF system is disclosed in which the input mixer of the system is also used as a switch to allow the local oscillator to be used as the transmitter oscillator. The switching mixer may also be used as an attenuator or signal modulator. A local oscillator is connected via a filter to a 90.degree. 3 db hybrid coupler. Two of the four ports of the hybrid coupler are coupled through impedance matching networks to reversely polarized mixer diodes. Bias circuits are connected to the mixer diodes for variably adjusting the bias current to the mixer diodes to thereby adjust their reflection/absorption characteristics. A second filter is connected between the first filter and the hybrid coupler for extracting an intermediate frequency signal. A third filter is connected to the fourth port of the hybrid coupler and to the antenna of the RF system. The first and third filters pass RF and local oscillator signals and block IF signals.

Abstract: An rf load is matched to an rf source by a matching network having series and shunt impedances connected between the source and load. A network coupled to the load derives a first rf signal responsive to rf energy reflected from the load. Another network responsive to the first rf signal derives plural rf signals, each having an amplitude that is a different function of the magnitude and phase angle of the reflected energy. In response to the amplitudes of the plural rf signals, the values of the series and shunt impedances are controlled.

Abstract: A reconfigurable shaped beam antenna system includes dual mode power divider with the output ports coupled to an equal number of radiators arranged in a row to provide a linear phase progression. One of the output ports of the power divider is selectively coupled to an additional radiator located at the opposite end of the row via 180.degree. phase shifter to maintain the phase progression.

Abstract: An input signal is supplied to a first port of a non-reversible circuit and those frequency components of the input signal applied to a second port of the non-reversible circuit which differ from the resonance frequency of a resonance element connected to the second port are absorbed by a resistive terminating element connected to the second port. On the other hand, a frequency component of the input signal which coincides with the resonance frequency is derived at the third port of the non-reversible circuit. By changing the resonance frequency of the resonance element, the frequency component of the input signal which are provided to the third port can be altered.

Abstract: A variable impedance synthesis circuit is provided for generating a selected impedance, whether real or complex, at a predetermined port. The variable impedance synthesis circuit exhibits the selected impedance in response to control signals applied thereto.

Abstract: A method and apparatus for directionally coupling two technically different microwave transmission lines, one being a waveguide and the other a stripline, in which a central conductor of the stripline is plunged into waveguide through a slot in a wall of the waveguide and loaded by capacitors or inductors. The width of the central conductor and values of the capacitors and inductors determines the desired coupling coefficient.

Abstract: An inductively coupled sensing circuit for use on a common cable communications system is disclosed. When used in conjunction with transceivers on a common cable system, the circuit is capable of both detecting signals and determining the direction of any colliding signals while the transceiver is operating. An inherently balanced bridge is created by coupling the transmitter lead between two elements of the sensing circuit. Each receiver is provided with means for determining the polarity of the sensing circuit, thereby determining the direction of any incoming signal. The use of this sensing circuit in a common cable system allows a hierarchy among cable users to be created thereby optimizing cable use. A left or right priority is determined by the polarity of an end signal transmitted at the end of each transmission.

Abstract: A 0.degree. and 180.degree. hybrid power divider/combiner includes a first quadrature hybrid and two other quadrature hybrids arranged in tandem with one output port of the first hybrid connected to an input port of the tandem arrangement and the other output port thereof connected to a delay of electrical length equal to that of the tandem arrangement. When an input signal is applied to one input port of the first hybrid with the other port terminated, two signals of reduced amplitude which are either in phase or of opposed phase (dependent on which input port receives the input signal) are produced at the output of the tandem arrangement and delay.

Abstract: The passive limiter is formed by at least two parallel micro-strip lines, a slot line orthogonal to the two micro-strip lines and a pair of diodes having the same polarity and placed on each edge of the slot line facing one another, the assembly of these three lines and the diodes forming at least two micro-strip line-slot line transitions.

Abstract: A differentiation and distribution switching system for connecting selected ones of a plurality of subscriber lines for receiving a desired signal. The system comprises at least one differentiation circuit connected to an input signal, a removable support for the differentiation circuit, and a plurality of couplers connected to an output line of the differentiation circuit. A switch is connected to each coupler and an associated one of the subscriber lines, whereby to connect a signal on the output line to selected ones of the subscriber lines.

Abstract: An n-way power divider, particularly useful where n.noteq.2.sup.x, includes an input and a plurality of outputs. The power applied to the input is coupled to the outputs, and phase shifters are associated with at least some of the outputs. The phase shift provided by each of the phase shifters is determined such that the reflected power waves from each of the outputs appearing at the input cancel. Because the circuit is reciprocal, it can also be used as a signal combiner with appropriately phased power-wave vectors at the inputs.

Abstract: A microwave feed forward passive coupling system for separation of at least a first and a second signal portion into at least first and second signal components of differing frequencies. The first and second signal portions have a majority of the second and first components respectively and a minority of the first and second components respectively. A second sample of the second signal portion and a part of the first signal portion are combined to produce substantially the second component. In addition, a first sample of the first signal portion and a part of the second signal portion are combined to produce substantially the first component.

Abstract: A surface acoustic wave filter having transmitting and receiving transducers, coupling transducers, as well as reflecting transducers which are arrayed on a piezo-electric substrate. The coupling transducers are so designed as to function as 3-dB directional couplers in order to obtain frequency characteristics over a wide range without developing ripples.

Abstract: Antenna system for double polarization in two high frequency bands of different frequency positions includes a orthomode transducer, in the following text called polarization filter having an antenna end terminal and two directional terminals, one being for right circular polarized waves, and the other being for left circular polarized waves. These directional terminals connect, respectively, with two frequency filters which separate the signals into the lower of the two high frequency bands, and the higher of the two high frequency bands. There are two 3-dB 90.degree. directional couplers, one of which handles right and left circular polarized signals of the lower frequency band, and the other of which handles right and left circular polarized signals of the higher frequency band. The polarization filter is constructed to be phase-symmetrical with respect to its transit paths.

Abstract: A microwave power divider is formed of a plurality of input ports (one or two pairs) and a plurality of output ports (one or two sets of three) which deliver three properly phased output signals in response to only one input signal at one input port of a pair of ports. A second signal at the second input port of the pair of ports similarly will cause three properly phased output signals to be delivered.

Abstract: A CATV subscription service control device has a switched buffer to prevent jamming signals from a switched attenuator from propagating throughout the system. The attenuator uses mutual inductance to achieve a high degree of attenuation.

Abstract: Four PIN diodes are connected, two in parallel oppositely directed at each f two ports of a 3 dB, quadrature hybrid which equally divide the power from an input port. The mismatch produced by the PIN diode resistance in parallel with the matching load resistance reflects part of the power, which combines at the two ports and exits at a fourth port of the hybrid. Direct-current bias to the PIN diodes is adjusted to vary the attenuation. There is also variable resistance and capacitance which serves as variable adjustments on the terminations of the hybrid when the diodes are unbiased.

Abstract: A module board comprised of a microstrip transmission line, terminating resistors and detectors is mounted over two coupling apertures spaced one quarter guide wavelength along a rectangular waveguide. The microstrip line has a length of five quarters of a wavelength as measured in the secondary line system. Output signals representing forward and reflected power flow in the waveguide are developed by the two detectors. This power sensor is low cost and compact and is suitable for a microwave oven.

Abstract: In a microwave delay equalizer for an input signal of a microwave frequency having an inevitable delay distortion, a directional coupler and a pair of resonators are placed, respectively, on a center area of a conductive base member and on those side areas thereof which lie on both sides of the center area. The coupler comprises a pair of distributed-constant elements electromagnetically coupled to each other either with an air space or a dielectric plate interposed therebetween and to the respective resonators to derive from the input signal supplied to one of the elements a delay equalized output signal in the other element. Each element has a length equal to an odd multiple of a quarter wavelength of the signal travelling therealong. Each resonator consists of at least one resonance piece.

Abstract: High levels of R.F. power are controlled and switched by means of a hybrid switching network that employs an intermediate power level switch matrix in conjunction with a pair of 8.34 (nominal) directional couplers and a phasing network. The two directional couplers are connected in tandem by two equal length transmission lines to form a broadband quadrature 3dB hybrid. Switching is accomplished by selectively inserting a 180.degree. phase shift means into the lower power carrying transmission line. The phase shifting means can be a length of transmission line, a solid state device, or a Schiffman type phase shifter.

Abstract: The fingers of a multistrip coupler for surface acoustic waves are weighted in at least one, i.e., input or output, track so as to match a predetermined energy profile for that track. In one embodiment, the weighting is achieved by apodizing the fingers of the multistrip coupler. In another embodiment, each finger is formed in a variable-amplitude zig-zag pattern. The invention is particularly advantageous when used to transversely couple surface acoustic wave resonators.

Abstract: An electrical filter network particularly suitable for use at microwave frequencies, comprises a main transmission path and a plurality of pairs of secondary paths interconnected by couplers which divide an incoming signal into components on the several paths and recombine the transmitted components to provide an output signal. Conditions are placed on the electrical lengths of the transmission paths; the magnitude of the frequency-independent components of phase change along the paths and the wave amplitudes in the paths.

Abstract: A millimetric wave high-pass filter is assembled from two axially-separate halves. Each half comprises a cast metal body having a channel which is divided to form two wave guides by means of a metal strip. The dimensions of the wave guides of the filter as a whole decrease towards a constriction at their centers while the strip is relatively thick at the constriction and tapers towards the ends. This configuration makes it possible to cast the filter in two halves with the body and the strip of each half being cast in a single piece. When assembled the halves meet at the level of the constriction.

Abstract: Acoustic surface wave devices of a novel class characterized by the provision of coupling means comprising at least several spaced filamentary electrical conductors extending over a first region and a second region for causing acoustic surface waves propagated across the coupling means in the first region to interact with acoustic surface waves propagated across the coupling means in the second region, by means of alternating electric signals induced on the filamentary electric conductors. The regions to be coupled are preferably formed on piezoelectric material, but modified forms of the coupling means can be made operable with other materials and suitable biassing fields.