Abstract: A solid state plasma monolithic microwave integrated circuit having single or multiple elemental devices with at least three terminals operating within the microwave, millimeter wave or terahertz bands, that can be configured within a parallel plate structure, which solid state plasma monolithic microwave integrated circuit comprises: (i) a semiconductor dielectric substrate (3); (ii) parallel plates (1, 2) which comprise an upper conducting parallel plate (1) and a lower conducting parallel plate (2) and which parallel plates (1, 2) are used to guide an electromagnetic wave; (iii) an isolating trench which is between the parallel plates (1, 2), and which is used to contain a solid state plasma; (iv) a distinct p-doped region and a distinct n-doped region which are within a first semiconductor region defined by the isolating trench below the upper conducting parallel plate (1), and which are connected to two electrical bias terminals, where at least one electrical bias terminal forms a radio frequency short t

Abstract: A power dividing circuit includes a first transmission sub-circuit having an input port and a first resonant circuit, a second transmission sub-circuit having a second resonant circuit, and a third transmission sub-circuit having a third resonant circuit. A matching element is coupled between the second transmission sub-circuit and the third transmission sub-circuit. An input carrier signal is divided into a first signal to the second transmission sub-circuit and a second signal to the third transmission sub-circuit through the first transmission sub-circuit. The second resonant circuit and the third resonant circuit generate resonant frequency to reduce high frequency harmonics under a specific frequency range in the input carrier signal. A power divider is also provided.

Abstract: A branch circuit includes a common antenna port and separates a first communication signal including a signal in a low band and a signal in a high band and a second communication signal that is a signal in a frequency band between the low band and the high band. The branch circuit includes a first-communication-signal-line-side band elimination filter and a second-communication-signal-line-side band elimination filter and SAW filter.

Abstract: A radar device for detecting an OUD (Object Under Detection) includes a signal source, a first antenna, a second antenna, a mixer, and a 90-degree coupler. The signal source is configured to generate an incident signal. The first antenna is configured to transmit the incident signal to the OUD. The second antenna is configured to receive a reflective signal from the OUD. The mixer is configured to generate a baseband signal according to the incident signal and the reflective signal. The second antenna is coupled through the 90-degree coupler to the mixer, or the signal source is coupled through the 90-degree coupler to the first antenna.

Abstract: One aspect provides an antenna. The antenna, in this aspect, includes a grounded segment extending from a metal chassis of an electronic device, and a feed portion coplanar with the grounded segment, the grounded segment and feed portion jointly tuned to cause the antenna to communicate in selected bands of frequencies.

Abstract: Embodiments of the present invention are directed to providing a time delay to a shortened trace in a differential microstrip trace pair. By adding back metal to a ground plane associated with a DC blocking capacitor, a time delay can be added to the shortened trace. The cutout associated with the longer trace remains unaltered. In a further embodiment, both cutouts can be modified with the addition of metal, with the cutout associated with the shorter trace receiving more metal than the other cutout. In a further embodiment of the present invention, a cutout associated with a connector can be modified to add back metal in the cutout. The cutout associated with the shorter trace is modified while the other cutout is left unchanged.

Abstract: An image rejection filter comprising a waveguide-type 90-degree hybrid coupler having an input port for receiving an input signal within a millimeter or submillimeter band, first and second output ports for dividing the input signal in two and outputting the divided signals, respectively, wherein the one signal deviates by a 90-degree phase from the other signal, and a branch port for outputting the signal; a pair of band pass filters: a waveguide-type first band pass filter whose one end is connected with the first output port and a waveguide-type second band pass filter whose one end is connected with the second output port; and a pair of radiowave absorptive terminations: a first radiowave absorptive termination connected to the other end of the first band pass filter and a second radiowave absorptive termination connected to the other end of the second band pass filter.

Abstract: A high-frequency module has a structure including balanced terminals, with high design flexibility and good transmission characteristics. Wiring patterns to be connected to balanced terminals of SAW filters of SAW duplexers are located on a second layer to a sixth layer of a layered body. The characteristic impedances of first wiring patterns defining a pair of parallel or substantially parallel lines match, the characteristic impedances of second wiring patterns defining a pair of parallel or substantially parallel lines match, the characteristic impedances of third wiring patterns defining a pair of parallel or substantially parallel lines match, and the characteristic impedances of fourth wiring patterns defining a pair of parallel or substantially parallel lines match.

Abstract: A signal transmission channel using a SIW between a transmitter and distant receiver. The SIW may include a MSL/SIW interface, be flexible, may use plug connections and/or may operate in a MMW band.

Abstract: What is described is a circuit arrangement and a method for synchronizing the communication signals between a repeater station (S) of a single-frequency simulcast radio communication network (N) and user terminals (T) with respect to a universal reference signal sent by a central station (M) of the network (N) communicating with the repeater station (S). A frequency offset is determined between a universal frequency reference signal received from the central station (M) and a local frequency reference signal of the repeater station (S), and in the repeater station (S) there are provided a first feedback control loop for supplying a signal for controlling a local oscillator of the repeater station (S) on the basis of the said determined frequency offset, and a second direct control loop for supplying a signal for compensating the residual synchronization difference of the local oscillator (16) to which the transmitter device of the station (S) is tuned.

Abstract: A two-terminal semiconductor device is formed on a semiconductor substrate. Two wiring patterns are respectively connected to terminals of the semiconductor device, and two electrode pads are respectively connected to the wiring patterns for connecting a signal input/output circuit formed on a separate substrate. Two parallel wiring patterns are respectively connected to the wiring patterns, and two reactance-circuit connection electrode pads are respectively connected to the parallel wiring patterns for electrically connecting a reactance circuit formed on the separate substrate separately from the signal input/output circuit.

Abstract: A circuit features a balun having an unbalanced input and a balanced output, and a differential coupler having a symmetrical structure about a center axis. The differential coupler has a differential input and a differential output, the differential input being coupled to the balanced output of the balun. An impedance element is coupled to a circuit node of the differential coupler at a point along the center axis. Other embodiments are also described and claimed.

Abstract: The present invention provides a frequency converter including a frequency conversion device capable of accommodating a Si-series MMIC and also a GaAs-series MMIC by using a magneto-resistance element. A frequency converter according to an embodiment of the present invention includes: a frequency conversion device having a magneto-resistance element with a magnetization free layer, an intermediate layer, and a magnetization pinned layer; a magnetic field application mechanism for applying a magnetic field to the frequency conversion device; a local oscillator for applying a local oscillation signal to the frequency conversion device; and an input terminal electrically connected to the above frequency conversion device for receiving an external input signal. Further, the local oscillator includes a magneto-resistance element capable of generating the local oscillation signal by outputting an AC voltage according to a resistance change thereof.

Abstract: A high-frequency circuit includes a dielectric substrate, a stripline formed on a surface of the dielectric substrate, a ground conductor provided on a back surface of the dielectric substrate, in which a pattern cut-out portion through which a part of the back surface of the dielectric substrate is exposed is formed, and a stub having a first end connected to an edge portion of the ground conductor defining the pattern cut-out portion and a second end arranged at a distance from the edge portion.

Abstract: A function control information transmitter 30 transmits function control information 40 for controlling the function of a terminal device 10 such as a mobile telephone. When the terminal device (mobile telephone 10) receives the function control information 40 from the function control information transmitter 30, the terminal device analyzes the received function control information 40 so as to control the function of the control object even without preparing in advance a correspondence table for controlling the function. Thus, it is possible to easily use the optimal function, application software, and a service in accordance the environment and the situation.

Abstract: An antenna assembly for a wireless communications device has an antenna, a filter circuit, and a connector constructed to engage a wireless communications device. A filter circuit includes a band-pass filter and a first notch filter disposed in serial electrical communication with the band-pass filter, the band-pass filter operable to permit the passage of oscillatory electrical signals in a first frequency range, the first notch filter operable to impede the passage of oscillatory electrical signals in a second frequency range, the second frequency range residing within the first frequency range.

Abstract: A function control information transmitter 30 transmits function control information 40 for controlling the function of a terminal device 10 such as a mobile telephone. When the terminal device (mobile telephone 10) receives the function control information 40 from the function control information transmitter 30, the terminal device analyzes the received function control information 40 so as to control the function of the control object even without preparing in advance a correspondence table for controlling the function. Thus, it is possible to easily use the optimal function, application software, and a service in accordance the environment and the situation.

Abstract: A direct conversion multi-band TV tuner includes: a plurality of RF (radio frequency) paths for processing the RF signal and for generating a plurality of processed RF signals, respectively; and a TSC (tri-state chopper) based quadrature frequency converter for receiving one of said processed RF signals and converting the received processed RF signal into a in-phase baseband signal and a quadrature baseband signals; wherein the TSC based quadrature frequency converter operates in accordance with a first set of periodic three-state control signals and a second set of periodic three-state control signals that are approximately 90 degrees offset from the first set of periodic three-state control signals.

Abstract: In an embodiment, a submillimeter wave heterodyne receiver includes a finline ortho-mode transducer comprising thin tapered metallic fins deposited on a thin dielectric substrate to separate a vertically polarized electromagnetic mode from a horizontally polarized electromagnetic mode. Other embodiments are described and claimed.

Abstract: A modulation circuit is provided that generates an output signal obtained by modulating an input signal with a local signal and includes a local input section that receives the local signal and generates the local signal and an inverted local signal obtained by inverting the local signal, a signal input section that receives the input signal and generates the input signal and an inverted input signal obtained by inverting the input signal, a first multiplying section that outputs from a terminal that receives the input signal a first multiplied signal obtained by multiplying the local signal with the input signal, a second multiplying section that outputs from a terminal that receives the inverted input signal a second multiplied signal obtained by multiplying the inverted local signal with the inverted input signal, an output section that adds the first multiplied signal to the second multiplied signal and generates the output signal, and a transmission line that sends to the output section the first multipl

Abstract: A multiplexer includes: a first band-pass filter for a first channel, which is formed in a microstrip line on a dielectric substrate and has a first branching characteristic having a center frequency of f1 and an attenuation pole at a frequency of fa1; and a second band-pass filter for a second channel, which is formed in a microstrip line on a dielectric substrate and has a second branching characteristic having a center frequency of f2 and an attenuation pole at a frequency of fa2. The following relationships (1) to (5) are satisfied: (1) f1<f2; (2) f1<fa1; (3) fa2<f2; (4) f2?fa1<(f2?f1)/2; and (5) fa2?f1<(f2?f1)/2. The second branching characteristic exhibits ?20 dB or less at the frequency of fa1 and the first branching characteristic exhibits ?20 dB or less at the frequency of fa2.

Abstract: An up-conversion mixer includes a first and a second hybrid couplers and a first and a second traveling-wave mixers is disclosed. The first hybrid coupler receives an input intermediate frequency (IF) signal and produces a first IF signal (IF1) and a second IF (IF2) signal, the second IF signal being 180 degree off-phase compared to the first IF signal. The first traveling-wave mixer mixes the first IF signal (IF1) and a first local oscillator (LO1) signal to produces a first radio frequency signal (RF1). The second traveling-wave mixer mixes the second IF signal (IF2) and a second local oscillator signal (LO2) to produces a second RF signal (RF2). The second hybrid coupler to combines the first RF signal and the second RF signal to produce an output RF signal. The use of the traveling-wave mixers allow for a wide bandwidth operation of the up-conversion mixer.

Abstract: An image rejection mixer including a first and a second hybrid couplers and a first and a second traveling-wave mixers is disclosed. The first hybrid coupler divides an input radio frequency (RF) signal to a first RF signal and a second RF signal, the second RF signal being in quadrature to the first RF signal. The first traveling-wave mixer mixes the first RF signal and a local oscillator (LO) signal to produces a first intermediate frequency (IF) signal. The second traveling-wave mixer mixes the second RF signal and the local oscillator signal to produces a second IF signal. The second hybrid coupler combines the first IF signal and the second IF signal to produce an upper sideband of the IF signals and a lower sideband of the IF signals. The use of the traveling-wave mixers allow for a wide bandwidth operation of the image rejection mixer.

Abstract: In an embodiment, a submillimeter wave heterodyne receiver includes a finline ortho-mode transducer comprising thin tapered metallic fins deposited on a thin dielectric substrate to separate a vertically polarized electromagnetic mode from a horizontally polarized electromagnetic mode. Other embodiments are described and claimed.

Abstract: A mixer circuit receives a local signal and an input signal so as to output a high-frequency signal generated based on the received signals. An output buffer receives the high-frequency signal. A band-pass filter having predetermined characteristics is formed by using the parameters of passive elements included in an output equivalent circuit as viewed from an output terminal of the mixer circuit and the parameters of passive elements included in an input equivalent circuit as viewed from an input terminal of the output buffer circuit.

Abstract: A wide dynamic range mixer which has a high linearity passive balun fabricated on a Si substrate for receiving an input RF signal and an active balun for receiving a local oscillator signal. The active balun includes high frequency, low voltage SiGe transistors to achieve low power amplification of the local oscillator signal. The output signals of the baluns are provided to a non-linear diode quad mixer device which provides a desired IF signal.

Abstract: A method of providing an input signal to a mixer circuit comprises coupling an output signal from a low-noise amplifier circuit to a mixer input of the mixer circuit via an AC coupling circuit, comprising an inductive of capacitive coupling circuit. For capacitive coupling configurations, a coupling capacitor is configured to have a capacitance value determined as a function of a transconductance sensitivity of the mixer circuit. For balanced output configurations of the low-noise amplifier circuit, matched coupling capacitors are used for coupling the balanced output signals to respective inputs of the mixer circuit. In one embodiment, the mixer circuit comprises a quadrature mixer circuit, which may be in a balanced or double-balanced configuration. In another embodiment, the mixer circuit comprises a four-phase mixer circuit, which may be configured as a balanced four-phase mixer circuit coupled to the low-noise amplifier circuit via inductive or capacitive embodiments of the coupling circuit.

Abstract: An integrated N-way Wilkinson power divider is described. In one embodiment, the N-way Wilkinson power divider uses a conductor layer with a cross-over (or cross-under) resistor insulated from the conducting layer by an insulating bridge. In one embodiment, the width of the transmission line underneath a cross-over resistor is adjusted to improve performance In one embodiment, a three-way Wilkinson power divider is formed using microstrip transmission lines on a single-layer substrate that supports the microstrip transmission lines, dielectric insulators, and resistors.

Abstract: A demultiplexer includes an antenna terminal, a reception filter connected to the antenna terminal, a transmission filter connected in parallel to the reception filter with respect to the antenna terminal and having a pass band center frequency that is different from the reception filter, a common inductance component connected between the ground terminal of the transmission filter and the ground terminal of the reception filter, and inductance components, which are different from the common inductance component, provided between the common inductance component and the reception filter and between the common inductance component and the transmission filter.

Abstract: A system and method for high power block upconversion having a stand-alone and surface-mountable component is provided. The HP-BUC system of the invention provides a “drop-in” component capable of mixing a local oscillator signal with an IF signal to produce an RF signal in the millimeter-wave and higher bands. In addition, the HP-BUC provides filtering of unwanted spurious signals and requires no further signal amplification prior to transmission, for example in a satellite communications system.

Abstract: A semiconductor device with integrated circuits includes superimposed layers provided at different levels on a substrate, and including a metal strip (3) formed in a reference layer and through which an electric current passes, a metal ground plane (4) formed in a layer situated at a level lower than the reference layer and having a slit (5) which lies below the strip while running alongside it, an electrostatic shield (6) formed in a layer located at a level lower than the ground plane and comprising a multiplicity of spaced out bands (7), made of an electrically-conducting material, that extends across the slit, and conducting junctions (4a, 4b) making it possible to electrically connect the ends of each band to the parts of the ground plane situated on either side of its slit.

Abstract: A double balanced mixer consisting of an RF balun, a local oscillator balun and a diode “quad” bridge circuit connected between the two baluns and where the IF output is taken at the center tap of the RF balun secondary transformer. A second harmonic termination consisting of an RLC resonant circuit is coupled across the diode bridge at the RF side. Each arm of the diode bridge, moreover, includes three series connected diodes. The mixer is in the form of a microminiature integrated circuit (MMIC) using HBT emitter-based junction diodes fabricated on a gallium arsenide (GaAs) substrate.

Abstract: A rat race circuit has an annular transmission line formed on a microstrip dielectric substrate. A terminal for port 1 is formed at any given position of the annular transmission line. Respective terminals for port 2 and port 3 are formed at respective positions distant from the position of port 1 in the counter-clockwise and clockwise directions each by a distance of ?g/4 (?g: effective wavelength). Moreover, at the position distant from the position of port 2 in the counter-clockwise direction by the distance of ?g/4, a terminator resistor (R=50?) is formed. A local oscillator signal is supplied to port 1, and first and second mixer inputs are connected respectively to port 2 and port 3. The local oscillator signal divider and a low noise converter using the divider are thus provided that are scarcely influenced by matching with respect to mixers and provide stable performance and high isolation.

Abstract: A line coupling structure for coupling a dielectric waveguide to a suspended line has the dielectric waveguide including dielectric strips and two conductor plates that are approximately parallel to each other, the dielectric strips and a circuit board being sandwiched between the conductor plates. The line coupling structure also has the suspended line including the conductor plates and a conductor pattern on the circuit board. The conductor pattern is arranged in a direction that is substantially perpendicular to the dielectric strips. A protruding conductor pattern that extends in the extending direction of the dielectric strips is provided at a crossing position of the conductor pattern and the dielectric strips.

Abstract: A 3-terminal harmonic mixer which solves the conversion gain, port impedance and isolation problems associated with known harmonic mixers. In particular, the 3-terminal harmonic mixer in accordance with the present invention provides harmonically pumped anti-parallel diode mixing operation by utilizing the inherent characteristics of complementary transistors.

Abstract: The invention is a combiner and a method for selectively combining modulated signals. The combiner includes a first modulator (12) with a selective input which receives at least one input signal and a first carrier signal and which outputs a first output modulated with the first carrier signal; a second modulator (14) with a selective input which receives at least one input signal and a second carrier signal and which outputs a second output modulated with the second carrier signal; means for combining (24?) the first and second amplified output signals to provide a combined output; and wherein the first and second carrier signals are selectably coherent or incoherent with the selection of first and second coherent carrier signals causing the combined output to comprise a single carrier of higher power and the selection of incoherent carrier signals causing the combined output to comprise two distinguishable carriers of lower power.

Abstract: A non-reciprocal circuit device has a length, a width, and a thickness denoted respectively by L1, L2, and L3, and the overall dimensions of 2.5 mm<L1<7.0 mm, 2.5 mm<L2<7.0 mm, and 1.0 mm<L3<3.5 mm. When a projected area of the substrate of the device is orthogonally projected on a plane parallel to a base surface of the substrate is denoted by S1, the substrate holds a proportional relation to S1/(L1×L2)=0.1 to 0.78. When a thickness of the magnet of the device is denoted by L4, the magnet holds a proportional relation of L4/L3=0.2 to 0.5. When a projected area of the magnet orthogonally formed on a plane parallel to a surface of the magnet is denoted by S2, they have a proportional relation of S1/S2=0.15 to 0.83.

Abstract: A mixer circuit according to the present invention includes a first differential transistor pair of two transistors, a second differential transistor pair of two transistors, an impedance element connected to the first differential transistor pair, an impedance element connected to the second differential transistor pair, an inductor connected to nodes A, B, a current source connected to node A, a current source connected to node B, and a capacitor. A mixer circuit with high conversion gain and small distortion can be obtained.

Abstract: A mixer having a diode quad, and which receives two RF signals at an RF input balun having primary and secondary windings. A resonant circuit arrangement includes at least a capacitor circuit element in parallel with the secondary winding to form an open circuit termination for the second harmonics of the input RF signals.

Abstract: The invention relates to an integrated semiconductor mixer, having a substrate (10), a radio-frequency balun (12) disposed on the substrate (10), a local oscillator balun (14) disposed on the substrate (10), an intermediate-frequency port (16) disposed on the substrate (10), and a mixer diode array (18), disposed on the substrate (10), that communicates with the radio-frequency balun (12), the local oscillator balun (14), and the intermediate-frequency port (16), in which the radio-frequency balun (12) is shielded from the local oscillator balun (14) by plated holes (20).

Abstract: To provide a high frequency switch capable of dealing with multiple frequency bands without having a plurality of switch circuits. A first diode (3) that conducts due to a bias current when a first switch (8) is closed is interposed between a first signal terminal (1) and a second signal terminal (5). A strip line (11) with the electrical length L1 is connected to the cathode of the first diode (3), the other end being grounded. At a position with the distance L2 from one end of the strip line (11), a capacitor (12) and a second switch (13) are connected to be equivalently grounded when a second switch (14) is closed.

Abstract: A high frequency switch configured particularly with FET switches. One end of second FET switch is connected between I/O port and reception port and the other end is ground. A parallel unit of strip line and capacitor is connected between second FET switch and I/O port. This parallel unit has the electrical length equivalent to ¼ wavelength of the high frequency signal input from transmission port.

Abstract: A power distributing and synthesizing device which comprises first to third signal terminals, first and second transmission lines and a resistor. The first signal terminal is provided at the connection portion between one end of the first transmission line and one end of the second transmission line; the second signal terminal is provided at the other end of the first transmission line; and the third signal terminal is provided at the other end of the second transmission line. The resistor is connected between the second signal terminal and the third signal terminal. LC serial resonators each comprising an inductor and a capacitor are respectively connected between the first to third signal terminals and a ground.

Abstract: It is described an image rejection, sub-harmonic frequency converter, realized in microstrip, particularly adapted to be used in mobile communication equipment, The converter avails of two identical sub-harmonic mixers employing each one or two pairs of diodes in antiparallel, obtained on a same silica substrate, and of a structure of hybrids performing appropriate phase combination adapted to suppress the image band in the converted signal. The mixers include filtering structures preferably consisting, but no limited to the same, of stubs &lgr;/4 long, at the local oscillator frequency, having a free end, in short or open circuit, respectively. According to an alternative embodiment, said stubs are replaced by appropriate filters implemented with concentrated structures (L and C) performing the same transfer function of the stubs in microstrip.

Abstract: The present motion detector unit effectively suppresses harmonic frequencies and is cost-effective to build. The motion detector unit includes a main casing which houses the main microwave circuit board (3). Enclosing the casing and the circuit board (3) is a cover. An antenna circuit board is attached to the bottom side of the main casing. The cover has partitioning walls at the bottom side of the cover which press against the main microwave circuit board (3) when the cover is enclosed over the casing. The circuit on the main microwave circuit board (3) includes a microwave oscillator for producing an oscillatory signal. The oscillator is coupled to a ground and to a filter which is a low-pass filter with a relatively wide stop bandwidth. The filter is then coupled to a transmitting antenna. A power supply is routed through the transmission antenna and provides DC voltage to the microwave oscillator. The oscillator is further coupled to a mixer.

Abstract: An image reject mixer for a low power battery operated radio telephone application. First and second doubly balance mixer circuits are connected to receive a differential radio frequency signal. Each of the doubly balance mixer circuits receives a local oscillator signal and a complimentary quadrature local oscillator signal. A first and second differential current produced by the first and second doubly balance mixture are combined in a quadrature combining circuit. The quadrature combining circuit adds an additional 90° of phase shift between the pairs of signals produced by each doubly balance mixture, so that the mixture output signals are added in a phase quadrature relationship thereby canceling unwanted spur and image components contained in the respective mixer output circuits.

Abstract: A single balanced downconverter includes an insulated substrate with a primary circuit and a secondary circuit, each consisting of an open annular foil element, located on opposite sides of the substrate in juxtaposition with each other and having mutual coupling. A pair of mixing diodes is connected across the ends of the secondary element, which has its center connected to ground. A 2nd local oscillator signal is applied to the primary circuit. A 1st IF signal is applied to, and a 2nd IF signal is developed from, the secondary circuit.

Abstract: An image reject mixer arrangement 1 comprises a transconductor 2, first and second mixer cores 3 and 4, first and second phase shifters 5 and 6 and a summer or combiner 7. The mixer arrangement 1 receives a single-ended RF voltage signal on a terminal 8, a differential local oscillator signal on I-LO terminals indicated at 9 and a 90° phase shifted differential local oscillator signal on Q-LO terminals 10, and provides differential IF output signals on output terminals 11. From the output of the transconductor 2 to the output of the combiner 7, the image reject mixer arrangement 1 carries signals in what can be described as a “current mode”, i.e. it is the current, not the voltage, which conveys the desired signal. In this current mode, it is advantageous to provide each active circuit block with a high output impedance and a low input impedance wherever possible.

Abstract: The present invention relates to a circuit intended to generate a negative conductance NG between two connection terminals A and B, including a first and a second transistor T1 and T2 connected as a differential pair between said connection terminals A and B.

Abstract: An output stage of a double balanced mixer having a first intermediate port and a second intermediate port includes an operational amplifier, an impedance and first and second current source devices. The operational amplifier has a first input port, a second input port and an IF output port, and the impedance is coupled between the first input port and the second input port. The first current source device has a first terminal coupled to both the first input port and the first intermediate port, which are coupled to one another. The second current source device has a second terminal coupled to both the second input port and the second intermediate port, which are coupled to one another.