Abstract: An integrated circuit including a structure of inductances on a semiconductor substrate, intended for operating at frequencies greater than several hundreds of MHz, including a first inductance formed by a conductive track and having first and second terminals respectively connected to each of the two ends of the conductive track, including a second inductance formed by the conductive track between the second terminal and any intermediary point of the conductive track connected to a third terminal, said second and third terminals forming the two terminals of the second inductance, and means for setting the third terminal to high impedance when the first inductance is used.

Abstract: An apparatus comprising a functional circuitry on a first die. Said function circuitry configured to drive an RF voltage isolation link with an RF signal responsive to receipt of a logic signal at a first logic state. Control circuitry modifies the frequency of the RF signal to spread harmonics to other than a fundamental frequency.

Abstract: The present invention relates to a hybrid balun apparatus and a receiver thereof. The hybrid balun apparatus comprises a passive unit, a first active unit, and a second active unit. The passive unit receives an input signal, and outputs an in-phase signal having an identical phase compared to the input signal and an inverse-phase signal having an inverse phase compared to the input signal. The first active unit compensates the in-phase signal of the passive unit corresponding to the input signal. The second active unit compensates the in-phase signal of the passive unit in response to the input signal.

Abstract: A signal transmission arrangement includes a transformer and a receiver circuit. The transformer has at least one primary winding and at least one secondary winding, each having first and second connections. The receiver circuit is connected to the secondary winding, and has an input and at least one output. The receiver circuit also has a differential input resistance approximating a short circuit. The receiver circuit is configured to convert a current pulse received at the input via the secondary winding to a voltage provided at the at least one output.

Abstract: An electronic circuit capable of carrying out communications by inductive coupling with minimum power consumption between substrates. Although the amplification factor of the amplifier 10a is 1, the amplification factors of the amplifiers 10b through 10d are, respectively, 2, 4 and 8. Amplification is carried out at the amplification factors 1 through 15 (=1+2+4+8) as a whole by a combination thereof. The transmit power control register 21 outputs ON and OFF signals to the respective amplifiers 10a through 10d so as to bring about transmit power responsive to the distance to a substrate having a receiver coil which is a destination of transmission (that is, the distance between a transmitter coil and a receiver coil), in further detail, so as to have an amplification factor by which transmit power proportionate to the distance can be obtained, and selects a combination of the amplifiers 10b through 10d.

Abstract: A radio receiver system, having two receiving antennas, two receivers, and a transformer transmitter, which is provided for the purpose of supplying radio signals of both antennas to each of the receivers, the transformer transmitter having a first winding and a second winding, wherein the two receiving antennas are connected to the end terminals of the first winding, and a first of the two receivers is connected to a center tap of the first winding and the second of the two receivers is connected to an end terminal of the second winding.

Abstract: An integrated circuit having voltage isolation capabilities includes a first area of the integrated circuit containing functional circuitry that is located in the substrate of the integrated circuit. A second area of the integrated circuit contains an integrated RF isolation circuitry for voltage isolating the functional circuitry. The RF isolation circuitry is located in the metal layers of the integrated circuit.

Abstract: A circuit package includes first and second units containing functional circuitry. At least one RF isolation link interconnects the first and second units and provides voltage isolation between the first and second units. The RF isolation link provides data between the first unit and the second unit using an RF carrier signal that sweeps between a first frequency and a second frequency.

Abstract: The present invention relates to a hybrid balun apparatus and a receiver thereof. The hybrid balun apparatus comprises a passive unit, a first active unit, and a second active unit. The passive unit receives an input signal, and outputs an in-phase signal having an identical phase compared to the input signal and an inverse-phase signal having an inverse phase compared to the input signal. The first active unit compensates the in-phase signal of the passive unit corresponding to the input signal. The second active unit compensates the in-phase signal of the passive unit in response to the input signal.

Abstract: A frequency converter that performs dual frequency conversion is provided. The frequency converter restricts noise occurrence and enables signal transfer with good linearity. The frequency converter performs dual conversion of a first signal (RF(+) and RF(?)) by using two signals including a second signal (LO1 (+) and LO1 (?)) and a third signal (LO2 (+) and LO2 (?)). Using a balun and an amplifying circuit that performs input/output operations in a single-ended manner, the frequency converter restricts NF degradation. By feeding optimum values of current into the first and second switching circuits and into the amplifying circuit, NF and linearity are optimized. The balun, the amplifying circuit, and the first and second switching circuits are formed on the same semiconductor substrate.

Abstract: The radio frequency integrated circuit (RFIC) electrostatic discharge (ESD) circuit includes an integrated circuit pin and a radio frequency (RF) ESD circuit. The integrated circuit pin provides coupling to an antenna. The RF ESD circuit is operably coupled to the integrated circuit pin, wherein the RF ESD circuit provides ESD protection at the integrated circuit pin, provides coupling of inbound RF signals from the antenna to low noise amplifier, and provides coupling of outbound RF signals from a power amplifier to the antenna.

Abstract: A radio receiver system having a plurality of receiving antennas and a plurality of receivers is described in which antenna signals of a multiplicity of the plurality of receiving antennas are fed to each of the plurality of receivers. The plurality of receiving antennas may be interconnected to the plurality of receivers more flexibly as a function of the desired reception strategy. In addition, the functionality of the entire system may also be maintained in the event of a defect or failure of one or more receiving antennas.

Abstract: A radio frequency circuit includes a first differential RF path and a second differential path. The first differential RF path includes at least one RF block that includes a first differential section and a second differential section, wherein the first differential section is symmetrical with the second differential section. The second differential RF path includes at least one RF block that includes a first differential section and a second differential section, wherein the first differential section is symmetrical with the second differential section. The first and second half differential sections of the at least one RF block of the first differential RF path are symmetrically placed on at least one layer around the first and second half differential sections of the at least one RF block of the second differential RF path, wherein the first and second half differential sections of the at least one RF block of the second differential RF path are fabricated on the at least one layer.

Abstract: A high gain input stage for a radio frequency transponder uses an amplifier for increasing a magnitude of an input signal. A DC bias circuit is used for controlling the operation of the amplifier. A resonant circuit is coupled between the amplifier and the DC bias circuit. The resonant circuit is used for receiving a signal generated by an electromagnetic field and for generating the input signal which is amplified by the amplifier. The resonant circuit has an inductor which is used to bias the amplifier thereby removing the need for a decoupling capacitor between the tuned circuit and the DC biasing of the amplifier. Multiple transponder inputs may be implemented in a single integrated circuit package.

Abstract: A stacked Gilbert cell mixer performs two frequency conversions in at least one of a wireless transmitter and receiver and includes a first stage of the stacked Gilbert cell mixer that converts a voltage signal input to the stacked Gilbert cell mixer to a current signal. A second stage of the stacked Gilbert cell mixer communicates with said first stage of the stacked Gilbert cell mixer and performs a first frequency conversion. A third stage of the stacked Gilbert cell mixer communicates with the second stage of the stacked Gilbert cell mixer and performs a second frequency conversion. Said first stage includes first and second transistors, said second stage includes third, fourth, fifth and sixth transistors and said third stage includes seventh, eighth, ninth and tenth transistors.

Abstract: The invention describes a system for electrical transmission in the field of garments and a corresponding transmitter for this. Electrical circuits in garments are coupled, preferably inductively in a wireless manner with electrical devices and/or electrical circuits in other garments, wherein electrical energy is transmitted via the coupling. Energy transmission in both directions is preferably possible, wherein a distributed system results with sources and devices that can be coupled with each other. The efficiency of the inductive energy transmission is increased by regulation of the frequency, preferably using resonance. In addition, means for information transmission are proposed.

Abstract: An on-chip differential inductor includes a 1st interwound winding having a substantially octagonal shape, or rectangular octagonal shape, and a 2nd interwound winding having a substantially octagonal shape, or rectangular octagonal shape, that is interwound with the 1st interwound winding. Both the 1st and 2nd interwound windings are on the same layer of the integrated circuit. Each interwound winding includes two nodes; one of node of each winding is commonly coupled to a reference potential. The other node of each winding is operably coupled to receive a respective leg of a differential signal.

Abstract: The radio frequency integrated circuit (RFIC) electrostatic discharge (ESD) circuit includes a transformer balun, an impedance matching circuit and a clamping circuit. The balun is operably coupled to transpose a single-ended radio frequency (RF) signal and differential RF signal. The balun includes a 1st winding that is coupled to the single-ended radio frequency signals and a 2nd winding that is coupled for differential RF signals. The impedance matching circuit is coupled to the 1st winding and provides, in conjunction with the impedance of the balun, impedance matching with an antenna coupled to the RFIC. The clamping circuit is operably coupled to the balun and/or to the impedance matching circuit and, in combination with the impedance matching circuit and/or in combination with the balun, provides ESD protection for the receiver section and/or transmitter section of the radio frequency integrated circuit.

Abstract: An integrated circuit including a structure of inductances on a semiconductor substrate, intended for operating at frequencies greater than several hundreds of MHz, including a first inductance formed by a conductive track and having first and second terminals respectively connected to each of the two ends of the conductive track, including a second inductance formed by the conductive track between the second terminal and any intermediary point of the conductive track connected to a third terminal, said second and third terminals forming the two terminals of the second inductance, and means for setting the third terminal to high impedance when the first inductance is used.

Abstract: A monolithic wireless receiver suitable for use in a global positioning system (GPS) or other radio frequency (RF) application suitably includes a mixed-mode integrated circuit and a stacked memory device. The mixed mode integrated circuit appropriately includes a digital portion and an analog portion on a common die. The analog portion implements an RF receiver circuit, and the digital portion includes a signal processor that communicates with the RF receiver. The memory device appropriately communicates with the integrated circuit to store electronic instructions and data for the signal processor. The monolithic receiver may be conveniently integrated into a portable electronics device such as a camera, personal digital assistant (PDA), portable phone or the like to provide location sensing or other RF functionality.

Abstract: A mixer with improved isolation between the RF and local oscillator frequency signals. The mixer has a substrate. A pair of cores are mounted to the substrate. Windings are wound on the cores to from a pair of baluns. A diode ring is connected between the baluns. The windings are formed from a first and second twisted pair of wires on one core and a third and fourth twisted pair of wires on another core. Some of the wires are wound on the cores but not twisted together. This winding configuration achieves superior balance between the baluns and good isolation.

Abstract: An RF antenna coupling structure includes a first transformer, a second transformer, and a transformer balun. The first transformer includes a primary winding and a secondary winding, wherein the primary winding of the first transformer is operably coupled to a power amplifier, and wherein the secondary winding of the first transformer has a desired output impedance corresponding to the operational needs of the power amplifier. The second transformer includes a primary winding and a secondary winding, wherein the primary winding of the second transformer is operably coupled to a low noise amplifier, and wherein the secondary winding of the second transformer has a desired output impedance corresponding to the needs of the low noise amplifier. The transformer balun includes a differential winding and a single-ended winding, wherein the differential winding is operably coupled to the secondary windings of the first and second transformers and the single-ended winding is operably coupled to an antenna.

Abstract: An integrated center frequency selectable resonant coupling network suited for use in an integrated circuit is disclosed. The network includes an integrated coupling transformer having a secondary winding for coupling to a load and a primary winding for coupling to a source; a first integrated capacitive circuit controllably coupled across one of the primary and secondary windings and when so coupled operable to resonate with the integrated coupling transformer at a frequency in a first frequency band; and a second integrated capacitive circuit coupled across a second one of the primary and the secondary windings that is operable to resonate with the integrated coupling transformer at a frequency in a second frequency band.

Abstract: A FET mixer uses a balun having a primary and secondary, with the primary coupled to an radio frequency signal input. The mixer also includes a pair of field effect transistors (FETs), wherein the gates are coupled to one another and to a local oscillator input. One of the source and the drain of the second of the two transistors is coupled at a node to one of the source and the drain of the other of the two transistors, and the node is coupled to ground. The other of the source and the drain of the first of the two transistors is coupled to one side of the secondary of the balun and the other of the source and the drain of the second of the two transistors is coupled to the other side of the secondary of the balun. An intermediate frequency signal output is coupled to a point in the circuit path between the first and second transistors.

Abstract: An on-chip differential inductor includes a 1st interwound winding having a substantially octagonal shape, or rectangular octagonal shape, and a 2nd interwound winding having a substantially octagonal shape, or rectangular octagonal shape, that is interwound with the 1st interwound winding. Both the 1st and 2nd interwound windings are on the same layer of the integrated circuit. Each interwound winding includes two nodes; one of node of each winding is commonly coupled to a reference potential. The other node of each winding is operably coupled to receive a respective leg of a differential signal.

Abstract: A tuner is provided for converting any selected channel in an input band to zero intermediate frequency. The tuner input is connected to the inputs of a plurality of input stages. Each input stage comprises tracking filters having a passband which is tunable across the tuning range of the input stage, where the tuning ranges of the stages form a contiguous or overlapping set so as to provide tuning across the whole of the input band. Only one of the input stages is enabled at a time with the disabled stages being depowered. A frequency changer converts the selected channel from the enabled input stage to substantially zero intermediate frequency.

Abstract: A radio frequency transformer has the two lines which constitute it on at least four levels of a printed circuit. Two of the four levels correspond to each line. In one variant the lines are wrapped onto a cube. The levels corresponding to one line are interleaved with the levels corresponding to the other one. The transformer has two input ports, one of which is connected to ground, and two output ports. This reduces the area and therefore the cost of the circuit or provides the facility to mount other components and thus other functions.

Abstract: A high gain input stage for a Radio Frequency Identification (RFID) transponder uses an amplifier for increasing a magnitude of an input signal. A DC bias circuit is used for controlling the operation of the amplifier. A resonant circuit is coupled between the amplifier and the DC bias circuit. The resonant circuit is used for receiving a signal generated by an electromagnetic field and for generating the input signal which is sent to the amplifier. The resonant circuit has an inductive portion which is used to bias the amplifier thereby removing the requirement of using a decoupling capacitor.

Abstract: A wireless IC interconnect system and method facilitates interconnections between first and second IC locations via a wireless transmission medium; the IC locations may be on the same chip or on separate chips. A signal to be conveyed is modulated, and the modulated signal is capacitively coupled to the wireless transmission medium—preferably a properly terminated microstrip transmission line (MTL) or a coplanar waveguide (CPW). The modulated signal is capacitively coupled from the wireless medium to a receiver which demodulates the modulated signal and provides the demodulated signal to the second IC location. In a preferred embodiment, the wireless transmission system conveys numerous signals simultaneously, with the signals modulated and demodulated with multiple access algorithms such as code-division (CDMA) and/or frequency-division (FDMA) multiple access algorithms.

Abstract: A transformer system comprises a transformer star winding to be coupled to an antenna system, and a transformer delta winding disposed with said transformer star winding. The transformer star winding includes a set of star elements and the transformer delta winding includes a set of delta elements each being substantially perpendicularly disposed with a corresponding star element from the set of star elements.

Abstract: Disclosed is an apparatus for modifying a radio frequency signal. In one embodiment, the apparatus includes a mixer, an amplifier module and an interface circuit. The mixer is configured to receive a first signal having a first frequency and a second signal having a second frequency, and to output a third signal which is a function of the first and second signals. The amplifier module includes a first amplifier stage and a second amplifier stage and is configured to amplify a communications signal which is then input into the mixer as the first signal. The first and second amplifier stages are in communication via a first signal path and a second signal path. The interface circuit is interposed between the mixer and the amplifier module, and inserted into the second signal path so that a DC bias current flows from the first amplifier stage through the interface module into the second amplifier stage.

Abstract: In order to eliminate the unnecessary power consumption caused by the increase in frequency associated with wireless communication systems using electromagnetic induction techniques, the wireless communication system of the present invention modulates and transmits a magnetic field in accordance with information. A close-range receiver is provided with an amorphous magnetic impedance element having an impedance which varies in accordance with the modulated characteristic of the magnetic field. Use of an amorphous magnetic impedance element in the receiver results in a reduction in power and increase in sensitivity of the device.

Abstract: A tuned low noise mixer (200) for use in radio frequency (RF) communications includes a transconductance amplifier (203) for amplifying an RF input signal (201). An impedance matching network (207) is formed using an impedance matching transformer with a tap connection (207') between primary and secondary coils. A mixer circuit (209) is then used for mixing a local oscillator signal (211) with the output of the impedance matching network (207) while a load network (213) provides a load to an output (215) of the mixer circuit (209). The invention provides a novel RF mixer topology that has a substantially low noise figure and a proportionally large power gain with low current drain for eliminating the need for an low noise amplifier (LNA) commonly used in RF mixer circuitry.

Abstract: An unbalanced to balanced antenna matching unit (AMU) is capable of operating over a relatively large frequency range by utilizing multiple transformers connected in series, with a set of bypass switches used to control the number of transformers that are "active" in the matching unit at any particular time. Complex impedance matching by the AMU is controlled by a variable capacitor in parallel with the multiple transformers and a variable capacitor in series with the unbalanced input. The parallel variable capacitor may be located on either side of the transformer arrangement. The transformer output may be configured to switch between matching either a low impedance antenna or a high impedance antenna.

Abstract: A dual-band radio receiver utilizes a single transformer to provide impedance matching between signal mixers from separate signal paths to their respective intermediate frequency filters. Thus, a dual-band radio receiver can be made eliminating one transformer and the printed circuit board space of one transformer. In addition, only one transformer needs to be frequency aligned or adjusted during manufacturing.

Abstract: First and second transmission line couplers (202, 204) one being configured in an asymmetrical open circuit configuration, the other being configured in an asymmetrical short circuit configuration, are coupled together to form a balun transformer (200). Balun transformer (200, 400, 500) can be implemented in three port bandpass filter (800) or other differential circuits to combine the functionality of a balun transformer and a two-pole filter into one circuit.

Abstract: An electronic tuning circuit for an AM radio receiver in which a signal of a specific frequency is selected from the input signal from an antenna is provided, this tuning circuit having a tuning transformer with a first winding and a second winding, the number of turns on the first winding being greater than the number of turns on said second winding, the input from the antenna being applied to the second winding of the tuning transformer, and further having two varactor diodes, each of which is connected in series with a DC-blocking capacitor, these series-connected varactor-capacitor combinations being connected in parallel with the first winding of the tuning transformer such that the polarities of the varactor diodes are mutually opposing.

Abstract: The antenna switch of the present invention switches from a portable radio's internal antenna to an external, vehicle adapter antenna. The second antenna is part of the vehicle adapter that supplies DC power to the vehicle adapter. A 1/4-wavelength transformer couples the internal antenna to the portable radio's transceiver. Diodes couple transformer and antenna to ground. A 1/2-wavelength transformer couples the vehicle adapter to the transceiver. When the portable radio is connected to the vehicle adapter, DC power is supplied to the diodes causing them to appear as a short thus making the first transformer appear as an open circuit. This causes a signal from the transceiver to be conducted to the second antenna on the vehicle adapter.

Abstract: A transformer having a core of soft magnetic material around which a first winding and a second winding are wound and a leakage inductance based on the magnetic coupling between these windings. The effective leakage reactance is minimized by adding a third transformer winding serially connected to a capacitor, the latter of which is varied to reduce the leakage reactance over a broad frequency range.

Abstract: A communication system 100 comprising a dispatch sub-system 100A, a plurality of transmitters 100B, and a plurality of mobile transceivers 100C is disclosed. An antenna coupler 410 and a location sensor 414 are coupled to one another via a coax cable 412. The bias current to the coupler is supplied by the location sensor 414 via the resistor 406. A detector 200 measures the voltage across the resistor 406 which is relative to the current flowing in to the antenna coupler 410. The detector 200 compares the measured voltage via comparators 218 and 238 and determines if the measured voltage is beyond a certain boundary. The NOR gate 244 routes the comparison result to a MPU 250. The MPU 250 processes the result and transmits a signal to a base station 104 via the mobile transceiver 118. The base station 104 decodes the received signal and presents it to a dispatch center 106.

Abstract: A radio frequency field strength enhancement system (402) having a member (404) with at least one tuning impedance (405) for adjusting a desired frequency response associated with the member (404) and means for retaining (408) the member (404) in close proximity to a radio frequency communication device (401) having an integrally mounted antenna system (214). When the radio frequency communication device (401) is brought within close proximity of the RF field strength enhancer (402), the power received or transmitted by the integrally mounted antenna system (214) in the RF communication device (401) is enhanced.

Abstract: A compensating amplifier for an automobile antenna which is relatively short and free from interference from high frequency band television signals. The amplifier includes an inductive element in a primary serial tuning circuit of a multiple tuning circuit of an antenna which is connected in parallel to a condenser, and the parallel resonant frequency of a parallel circuit which is formed by the inductive element and the condenser is set at approximately the same resonant frequency as the resonant frequency of the antenna.

Abstract: Apparatus is provided for coupling one of two signal sources to the antenna terminals of a television receiver. An antenna switch is provided which includes solid state switching elements which when receiving a biasing voltage connects one of two input ports to an output port for delivering a signal to a television receiver. In the unbiased state, the remaining input port is connected to the television receiver antenna terminals. High isolation is provided to prevent stray radiation from one signal source being received by a second signal source.

Abstract: An antenna input circuit for an electronic tuning type AM receiver for automobiles, which is connected to a capacitive antenna represented by an equivalent circuit composed of an antenna capacitance connected in series with an antenna electromotive force and a cable capacitance connected in parallel with them. A tuning transformer and a variable capacitance diode are connected in series with the capacitive antenna, and an additional capacitance is connected to the tuning transformer so that the current flowing in the additional capacitance also flows in one part of the tuning transformer, thereby providing an improved S/N ratio in the medium-frequency receiving band. Another capacitance is connected to the output terminal of the antenna input circuit, to reduce its output impedance. A capacitance for image interference ratio improving use is connected to the additional capacitance and the output impedance reducing capacitance.

Abstract: An RF input tuning circuit in a UHF electronic tuner uses a semicoaxial resonant cavity circuit which feeds amplifier and other tuning circuits not of the semicoaxial type, such as lumped constant or strip-line types.

Abstract: An electrical frequency responsive circuit comprising a first coil constructed of wire having an insulating coating thereon wound in a single layer about an axis of generation, and a second coil, also constructed of wire having an insulating coating thereon wound about an axis of generation in a single layer, said coils being axially related and having diameters and/or pitch to provide inductance and capacitance between the coils which is at least initially adjustable whereby the circuit is responsive to an electric signal having a predetermined electrical frequency imposed across the coils to provide frequency band suppression about the predetermined frequency.

Abstract: An antenna system is disclosed for plural band radio receivers having a common antenna. The system is especially adapted for AM/FM automobile broadcast receivers and may be used with a CB transceiver with a tri-band antenna. An impedance transforming means is provided at the base of the antenna and a single transmission line or lead-in cable extends from the impedance transforming means to the AM/FM receiver. The impedance transforming means has a high input impedance for the AM and FM bands and a relatively low output impedance to minimize the signal loss in transmission from the antenna to the receiver. The impedance transforming means includes a field effect transistor in a common source configuration and means are provided to produce substantially 100% voltage degeneration for both AM and FM signals.

Abstract: An automatic gain control circuit for an AM receiver uses a signal having the same wavelength but reversed in phase with the signal in the antenna circuit. A variable resistance attenuator element such as a biased FET or PIN diode is used in the external antenna circuit having a winding to selectively attenuate the input signal to the tuning circuit including a secondary winding. Gain control is performed in an analog manner with respect to the input signal of the external circuit.