Abstract: The disclosure relates to a communications system having a transmitter and receiver connected via a transmission line. An example communications receiver (202) comprises: a pair of input connections (211, 212) for connecting to a transmission line (203); a termination resistance (213) equal to a characteristic impedance (Zc) of the transmission line (203); an air core transformer (205) having an input coil (206) connected to the pair of input connections (211, 212) via the termination resistance (213); and a comparator circuit (208) connected to an output coil (207) of the air core transformer (205), the comparator circuit (208) configured to provide an output signal (504) responsive to detection of voltage pulses across the output coil (207).

Abstract: A communication barrier arrangement includes a first driver having a first interface for receiving signals from a first device destined for a second device, an isolation barrier including a first transformer for signal transfer and having a primary winding connected to the first driver and a secondary winding, a second driver connected to the secondary winding and having a first connection terminal for output of the signals towards the second device, a first signal conditioner having a second connection terminal for receiving the signals from the second driver and a second interface for delivering them to the second device and a protection circuit including a resistor in parallel with a first capacitor, the protection circuit being connected between the first and second connection terminals.

Abstract: A system and method of adding a high-rate channel to a legacy baseband bus includes a bus communicatively coupled to a transmitter and a receiver via one or more transformer couplers, where the transmitter and receiver transmit and receive a first signal over the bus utilizing a differential mode. The system also includes at least two modems coupled to the bus, where a first modem transmits a second signal over the bus for receipt by a second modem, where the at least two modems are each coupled to the bus via the one or more transformer couplers, where the second signal is transmitted over the bus utilizing a common mode, and where the first signal and the second signal are spatially separated on the bus based on an isolation between the common mode and the differential mode.

Abstract: The invention relates to a method for evaluating the state and the quality of low-voltage networks, in the branched system of which there is a plurality of connected loads, by determining network measurement data by means of power quality measuring and testing devices and transferring the network measurement data, by means of a standard interface, to a control system or in retrievable form to a server. According to the invention, the overvoltage protection devices, which are or can be used in the low-voltage system and have a self-diagnosis unit and an existing wireless or wired standard interface for data transfer, are able to determine network measurement data by means of integrated or adapted power quality measuring and testing devices.

Abstract: A signal transmission circuit that is connected to a communication unit by a signal wiring and performs signal transmission to/from the communication unit via the signal wiring includes: a direct-current supply unit that outputs a direct current with a variable output voltage, superimposes the direct current on the signal, and supplies the direct current to the communication unit via the signal wiring; a signal reception unit that receives the signal from the communication unit; and a signal processing unit that performs signal processing based on the signal received by the signal reception unit, wherein the signal reception unit has an equalizer function that adjusts a waveform of the signal to compensate for attenuation due to the signal wiring, and the output voltage is controlled based on an equalizer setting value used for control of the equalizer function.

Abstract: Various embodiments relate to a de-emphasis (DE) controller in a wireline transmitter, including: a digital decoder configured to receive a DE control value and configured to produce a bias control value, an N1 control value, and an N2 control value; a bias controller configured to vary the bias current for a de-emphasis circuit based upon the bias control value; an N1 controller configured to activate a number of N1 unit cells in a delayed line driver based upon the N1 control value; and an N2 controller configured to activate a number of N2 unit cells in a non-delayed line driver based upon the N2 control value, wherein the N1 control value plus the N2 control value varies for different DE control values, and wherein the bias control value is based upon the N1 control value plus the N2 control value.

Abstract: A system (1) for transferring electric energy and data is proposed, comprising a primary circuit (10) and a secondary circuit (20). The primary circuit (10) comprises: an electric energy source module (11); a primary inductive element (12) connected to the source module (11); a primary transceiver module (13) configured to encode data into electromagnetic signals and decode electromagnetic signals into data, and a pair of electrically conductive primary transceiving armatures (14a, 14b) connected to the primary transceiver modules (13). The secondary circuit (20) comprises: an electric energy conversion module (21); a secondary inductive element (22) connected to the conversion module (21); a secondary transceiver module (23) configured to encode data into electromagnetic signals and decode electromagnetic signals into data, and a pair of electrically conductive secondary transceiving armatures (24a, 24b) connected to the secondary transceiver module (23).

Abstract: A converter includes a transformer, a primary side switch, a load detection circuit, a state detection circuit and a control circuit. The transformer is configured to output a voltage to a load. The primary side switch is coupled to a primary winding and a primary ground terminal. The load detection circuit is configured to detect a load state of the load and output a load state signal. The state detection circuit is configured to detect a reference time point. The control circuit is configured to output a control signal to turn on or off the primary side switch. The control circuit further sets a blanking time according to the load state signal, such that the primary side switch is turned on when a drain-source voltage of the primary side switch is at a valley of the resonance after the blanking time starting from the reference time point.

Abstract: A device includes a transformer that further includes a primary and a secondary windings. A switch is coupled to the primary winding, and this switch is controlled by the received digital input signal. An oscillator is further formed on the secondary winding where the oscillator oscillates in response to variations of the received input signal. A detector coupled to the oscillator will then detect the oscillations in response to the variations of the received input signal. Thereafter, the detector generates a digital output based on the detected oscillations.

Abstract: The present application relates to a transceiver, TX/RX PHY, and a method of operating the TX/RX PHY arranged for bi-directional data communication of a node with a counterpart node connected to in a point-to-point network using differential mode signaling over a single twisted-pair cable. A TX adjustment component is arranged in a TX path of the TX/RX PHY and configured to adjust a TX data communication signal generated by the TX/RX PHY for transmittal to the counterpart node. The TX adjustment component is further configured to accept information about a common mode signal detected on the single twisted-pair cable and to adjust the TX data communication signal to at least weaken the common mode signal occurring at the counterpart node in response to transmitting the TX data communication signal.

Abstract: A voltage regulator circuit included in a computer system may include multiple phase circuits each coupled to a regulated power supply node via a corresponding inductor. The phase circuits may modify a voltage level of the regulated power supply node using respective control signals generated by a digital control circuit that processes multiple data bits. An analog-to-digital converter circuit may compare the voltage level of the regulated power supply node to multiple reference voltage levels and sample the resultant comparisons to generate the multiple data bits.

Abstract: A power line communication device including a current path provided between a first terminal and a second terminal. A coupling circuit includes a first circuit of a first inductor connected in parallel with a first capacitor and a first resistor, wherein the coupling circuit is connected between the first and second terminals. A sensor is configured to sense a communication parameter of the coupling circuit. The communication parameter may be a resonance of the first circuit, the quality (Q) factor of the resonance, the bandwidth (BW) of the coupling circuit, the resistance of the first resistor, or the impedance of the first circuit. A transceiver is adapted to couple to the first and second terminal to transmit a signal onto the current path or receive a signal from the current path responsive to the parameter of the coupling circuit and a level of current in the current path sensed by the sensor.

Abstract: A system for communicating with a wireless device including a base including a front surface; a plurality of communication coils disposed on the front surface and arranged in a matrix, the coils being tuned to a near-field communication frequency; a selector coupled to the coils; at least one memory storing instructions; and at least one processor coupled to the selector and executing the instructions to perform operations. The operations include at least receiving a plurality of feedback signals associated with the coils; identifying a selected one of the coils associated with a strongest one of the feedback signals; and causing the selector to couple the selected coil with a wireless communication module.

Abstract: A system on a package (SOP) can include a galvanic isolator. The galvanic isolator can include an input stage configured to transmit an input RF signal in response to receiving an input modulated signal. The galvanic isolator can also include a resonant coupler electrically isolated from the input stage by a dielectric. The resonant coupler can be configured to filter the input RF signal and transmit an output RF signal in response to the input RF signal. The galvanic isolator can further include an output stage electrically isolated from the resonant coupler by the dielectric. The output stage can be configured to provide an output modulated signal in response to receiving the output RF signal.

Abstract: A device for measuring a measurement variable, wherein a first inductance is supplemented by a capacitance to form a parallel resonant circuit and is excited by a micro-controller. A measurement inductance coupled to the first inductance is measured by the micro-controller. Therefore, a measured variable can be deduced and only very few components are required in addition to a micro-controller.

Abstract: A control circuit for suppressing electromagnetic interference signal has an input and an output and a variable gain filter circuit with a first gain factor that is variable. The variable gain filter circuit receives a signal indicative of an electromagnetic interference signal and outputs a signal to a controlled signal source, which a second gain factor. The control circuit also has a controller operably connected to the variable gain filter circuit. The controller receives a signal indicative of an output signal at the output of the control circuit and outputs a control signal to the variable gain filter circuit. The control signal is based on the signal indicative of the output signal at the output of the control circuit, and the control signal controls the first gain factor and reduces the electromagnetic interference signal.

Abstract: Apparatus and methods for performing wireless communications are provided. In some embodiments, an apparatus includes a transformer including a first winding, a second winding, and a third winding. The apparatus also includes a first transmitter circuit coupled with the first winding, and a second circuit coupled with the second winding. The third winding is coupled with an antenna. The first transmitter circuit is configured to transmit a first signal to the antenna via magnetic coupling between the first winding and the third winding. The second circuit is configured to tolerate without damage a second signal from the first transmitter circuit, wherein the second signal is generated from the first signal via magnetic coupling between the first winding and the second winding. A turn ratio between the first winding and the second winding can be configured to limit a voltage of the second signal to be within a pre-determined threshold.

Abstract: An apparatus and a method for range extension for a combined data and power line are provided. Further, a bus system is provided. The design is based on a supply voltage that is transmitted via the combined data and power line being refreshed by a charge pump. Further, there may be provision, by way of example, for a data signal that is transmitted via the combined data and power line to be refreshed using the likewise transmitted supply voltage.

Abstract: Multiple coil systems and methods are disclosed in which transmitter and receiver inductors, or coils, are coupled in a configuration for wirelessly transferring data and/or power among them. In preferred implementations, the systems and methods are used for transmitting data using pairs of coupled coils. One preferred aspect of the invention is that the coils are not permanently affixed in physical proximity to one another, but can be moved and/or interchanged.

Abstract: A video communication method and system, and a terminal are presented. A sending terminal sends an invite message to a receiving terminal. The sending terminal receives a reply message. The sending terminal determines that a video encoding/decoding format supported by the sending terminal does not include a video encoding/decoding format included in the reply message. The sending terminal obtains a video encoding/decoding format supported by both the sending terminal and the receiving terminal. The sending terminal performs video communication with the receiving terminal by using the obtained video encoding/decoding format.

Abstract: A method includes digital/analog conversion of a digital signal modulated by information to provide a modulated initial analog signal having a crest factor greater than one, and amplification of the initial analog signal to provide an amplified modulated signal. A modulated channel analog signal derived from the modulated amplified analog signal is transmitted over a communications channel, with impedance of the communications channel varying during the transmission. The method further includes at least one determination during the transmission of a peak-clipping rate of the amplified analog signal over at least one time interval, and an adjustment of a level of the initial analog signal as a function of the determined peak-clipping rate.

Abstract: An electrical coupler includes: a sending transformer having a winding for receiving data signals and two windings connected in series with a common point and two terminals to be connected to a first wires pair of a bus to deliver the data signals at the first winding terminals to said wire pair; a receiving transformer having two windings connected in series with a common point and two terminals to be connected to a second pair of wires of said bus to receive data signals on the pair of wires and a winding for delivering said data signals; and a galvanic isolation transformer with a first winding, the terminals of which are connected to the coupler's power supply pins, and second and third windings connected in series with a common point connected to a mechanical ground and the respective free terminals connected to the common terminals of sending and receiving transformers.

Abstract: Methods and apparatus are disclosed for applying successive multi-rank beamforming strategies (e.g., successive preceding strategies) for the design of precoders over a set of parallel channels. Successive beamforming is applied to a narrow band channel model and is also applied for finer quantization of a single beamforming vector (e.g., recursive beamforming). A first embodiment provides the optimal approach with high complexity. An alternative embodiment provides successive beamforming for near optimal precoding selection with medium complexity. A low complexity method for precoder selection is also provided wherein a channel representative matrix for the set of parallel channels is determined and successive beamforming on the calculated channel representative is applied.

Abstract: A circuit for compensation of baseline voltage wander operating at an input of an isolator is disclosed. The circuit can compensate electronically the frequency response of an isolation circuit (e.g., a transformer) by increasing the pass band in the low frequency region in order to minimize the baseline wander caused by low inductance windings. The compensation circuit can be used to inject a current ramp proportional to the amplitude and the duration of the pulse and inversely proportional to the open circuit inductance of the isolation circuit.

Abstract: A system includes a first galvanic isolator, a second galvanic isolator, a sensor, and a monitoring module. The first galvanic isolator includes a first electrical insulator. The second galvanic isolator is connected in series with the first galvanic isolator and includes a second electrical insulator. The sensor generates a first output signal based on an electrical characteristic of one of the first and second electrical insulators. The monitoring module, based on the first output signal, selectively generates a signal indicative of a failure of at least one of the first and second electrical insulators.

Abstract: A network transceiver is disclosed. An example system includes a first networking transceiver including a first port and a second port, the first transceiver configured to: negotiate, for use with the first port, a first data rate, negotiate, for use with the second port, a second data rate that is slower than the first data rate, and a second networking transceiver communicatively coupled with the first networking transceiver to communicatively couple computing devices connected to the first networking transceiver to a multi-lane communication port, the second networking transceiver to negotiate, for the multi-lane communication port, a third data rate for communications between the multi-lane communication port and the second networking transceiver.

Abstract: A transmit/receive switch architecture is provided which reuses a power amplifier's transformer as part of the low noise amplifier (LNA) input matching network. A front-end circuit includes a transmit/receive switch. The transmit/receive switch includes a transformer that includes primary winding and secondary winding. The transmit/receive also includes a transistor, where a drain of the transistor is connected to the secondary winding and a gate of the transistor is configured to receive a control signal. The transmit/receive switch operates as a receive switch when the control signal is low and inputs of the primary winding are either shorted or at open circuit. The transmit/receive switch operates as a transmit switch when the control signal is high.

Abstract: A signal transfer device includes a signal transmitter, a first amplitude adjustment component, an adjustment signal output component, a detector and a second amplitude adjustment component. The signal transmitter outputs signals to first and second transfer paths based on single-phase or differential input signal. The first amplitude adjustment component adjusts at least one of amplitudes of the signals transferred to the first and second transfer paths based on a predetermined amplitude ratio. The adjustment signal output component outputs adjustment signals to the first and second transfer paths. The detector detects the adjustment signals. The second amplitude adjustment component adjusts at least one of the amplitudes of the signals transferred to the first and second transfer paths based on detection result of the detector.

Abstract: A magnetically-coupled structure is integrated with an integrated circuit in back end-of-line (BEOL) digital CMOS fabrication processes. A differential primary (or secondary) coil is formed by patterning a thick copper (Cu) metal layer, and a single-ended secondary (or primary) coil is formed by patterning a thick aluminum (Al) top metal bonding layer. Crossovers and/or cross-unders are formed using thin metal layers. One embodiment provides a stacked balun with a differential primary input winding defined in the copper layer, directly underneath a single-ended spiral winding defined in the aluminum layer. The spiral forms the single-ended secondary output of the balun and is rotated by 90° to prevent metal shorting for its cross-under connections. Another embodiment provides a transformer with one differential primary (or secondary) coil defined in the copper layer and another differential secondary (or primary) coil defined in the aluminum layer and adding a center tap.

Abstract: System, methods and apparatus are described that facilitate transmission of data, particularly between two devices within an electronic apparatus. Data is selectively transmitted as N-phase polarity encoded symbols or as packets on differentially driven connectors. A data transfer method comprises encoding data and control signals in a sequence of symbols to be transmitted on a plurality of connectors, and transmitting the sequence of symbols on the plurality of connectors. Each symbol may be transmitted using a combination of a phase state of a first pair of connectors, a polarity of a second pair of connectors, and a selection of at least one undriven connector. Transmission of each symbol in the sequence of symbols may cause a change of state for at least one of the plurality of connectors.

Abstract: A portable, self-powered, interface converter for converting between Ethernet over twisted pair cables and Ethernet over optical fiber is described. In one implementation, the device may include a first interface to a power-over-Ethernet connection and a second interface to provide a connection to receive fiber optic cabling. A power-over-Ethernet (PoE) circuit may derive power from the PoE connection and output a corresponding power signal. A transcoder may perform physical layer conversion between Ethernet communications over twisted pair cabling connected to the first interface and Ethernet communications over the fiber optic cabling. The transcoder may be powered by the power signal output by the PoE circuit.

Abstract: Disclosed are various embodiments for communicating information between various electronic components. A local device may comprise a transmitter to convert communication signals into modulated signals. Modulated signals are injected into a shared power supply line. The remote device may comprise a receiver for identifying the injected signal, demodulating the injected signal, and processing the demodulated signal.

Abstract: A system on a package (SOP) can include a galvanic isolator. The galvanic isolator can include an input stage configured to transmit an input RF signal in response to receiving an input modulated signal. The galvanic isolator can also include a resonant coupler electrically isolated from the input stage by a dielectric. The resonant coupler can be configured to filter the input RF signal and transmit an output RF signal in response to the input RF signal. The galvanic isolator can further include an output stage electrically isolated from the resonant coupler by the dielectric. The output stage can be configured to provide an output modulated signal in response to receiving the output RF signal.

Abstract: In one aspect, an optical media converter is provided for use within aircraft data networks. In one example, the optical media converter converts electrical doublet signals to optical Manchester signals, and vice versa. In an illustrative example, the optical media converter includes a receiver circuit coupled to a fiber optic port for receiving a Manchester-encoded input signal using an edge-coupled filter that filters out signals not associated with edges within the time-varying input signal Manchester signal. The optical media converter also provides, for example, for high common mode rejection and includes logic to correct for bit-width skew. The optical media converter is well-suited for use in converting doublet signals generated by a serial interface module of a line replaceable unit of an ARINC 629-compatible system into optical Manchester signals for transmission over a fiber optic bus system interconnected by a star coupler.

Abstract: The present invention relates generally to addressing performance issues in xDSL communication systems, and more particularly to methods and apparatuses to measure and characterize CM noise impacting a DSL line in a customer premises, measurements and characterization of the projection of these CM signals in Differential Mode (DM), and finally a derivation of an estimate of the loop balance.

Abstract: A cascode common source and common gate LNAs operating at 60 GHz are introduced and described. The cascode common source LNA is simulated to arrive at an optimum ratio of upper device width to the lower device width. The voltage output of the cascode common source LNA is translated into a current to feed and apply energy to the mixer stage. These input current signals apply the energy associated with the current directly into the switched capacitors in the mixer to minimize the overall power dissipation of the system. The LNA is capacitively coupled to the mixer switches in the I and Q mixers and are enabled and disabled by the clocks generated by the quadrature oscillator. These signals are then amplified by a differential amplifier to generate the sum and difference frequency spectra.

Abstract: Provided are a communication system and a communication device capable of suppressing attenuation of a communication signal superimposed upon a control pilot line. This output circuit (20) sends a control pilot signal which has been generated at a voltage generation source (21) to an input circuit (60). Between the control pilot line (4) and the ground line (3) of the output side of the output circuit (20), a communication unit (30) is connected via a transformer (31). Between the control pilot line (4) and the ground line (3) of the input side of the input circuit (60), a communication unit (70) is connected via a transformer (71). Between the output circuit (20) and the transformer (31), a lowpass filter (33) is interposed. Between the input circuit (60) and the transformer (71), a lowpass filter (73) is interposed.

Abstract: A first integrated circuit die receives input data from a plurality of input channels and combines the input data from the plurality of input channels into combined data. The first integrated circuit die transmits the combined data across an isolation communication channel. A second integrated circuit die that is coupled to the isolation communication channel decodes the transmitted combined data and supplies the decoded transmitted combined data to respective output channels corresponding to the input channels.

Abstract: An aircraft includes a first electrical connector configured to couple with a first power cable, a first data communication network and a first modem coupled to first electrical connector and first data communication network and is configured to transmit data received at first electrical connector through first power cable to first data communication network and to transmit data from first data communication network to first power cable through first electrical connector. The aircraft additionally includes a second electrical connector configured to couple with a second power cable, a second data communication network and a second modem coupled to second electrical connector and to second data communication network and is configured to transmit data received at second electrical connector through second power cable to second data communication network and to transmit data from second data communication network to second power cable through second electrical connector.

Abstract: In a communication system, nodes are coupled to a transmission path in a bus topology. The nodes communicate with each other via the transmission path using communication signals that have a communication frequency and are synchronized with a power supply signal. Each of the nodes includes a coupling portion that transmits and receives the communication signal and the power supply signal using electromagnetic induction in non-contact with the transmission path. Each of the nodes determines whether a collision of the communication signals occurs on the transmission path based on a voltage level of a signal that has the communication frequency and is induced at the coupling portion.

Abstract: A modem for symmetric bi-directional transporting of an Ethernet signal, comprises a port connected to a physical layer module adapted to receive and transmit a single Ethernet signal, a data splitter for splitting the Ethernet signal into the configurable number of downstream data signals, another port comprising the configurable number of DSL ports coupled to the data splitter. Each port is adapted to transmit a separate downstream signal. Each transmitted downstream signal is transmitted via a corresponding telephone line connected to the port. Each port is further adapted to receive a separate upstream signal. Each received upstream signal is received over the corresponding telephone line connected to the DSL port, and a data collection and reorganization unit coupled to the DSL ports and adapted to assemble the upstream signals into the single Ethernet signal for transmission by the physical layer module.

Abstract: A first communication device is connected in a conductive state to a first power line extending from a secondary side of a transformer in a high-voltage power receiving apparatus to a primary side of breakers in a plurality of distribution boards that receive power supply from the transformer. A plurality of second communication devices are respectively connected to a plurality of second power lines respectively extending from a secondary side of the breakers in the plurality of distribution boards. Each second communication device performs power line communication using the second power line connected thereto as a transmission path. Upon receipt of a communication signal, each of the first communication device and the plurality of second communication devices generates a new communication signal including information included in the communication signal and sends the new communication signal through power line communication.

Abstract: The present invention relates to an apparatus for coupling a modem to a power supply network for transmitting data via the power supply network, comprising a mains connection, which is configured to connect the apparatus to a phase conductor, a neutral conductor and a protective earth conductor of the power supply network, with the apparatus comprising a first transformer element comprising a primary side winding, a first secondary side winding and a second secondary side winding, and with the apparatus comprising a second transformer element comprising a primary side winding, a first secondary side winding and a second secondary side winding.

Abstract: Method and apparatus for transmitting combined power and data. In one embodiment, the apparatus comprises an isolation barrier; a drive controller for generating a first waveform comprising a plurality of data signals for transmitting different types of data, where the drive controller couples the first waveform to a first side of the isolation barrier to produce a second waveform on a second side of the isolation barrier; and a circuit controller coupled to the second side of the isolation barrier, where the circuit controller is powered by the second waveform, and where the circuit controller controls a circuit based on the plurality of data signals.

Abstract: A system for the coexistence between a plurality of wireless communication modules sharing a single antenna is provided, including an antenna, first and second transceiving paths, and first and second wireless communications modules. The first transceiving path is coupled to the antenna. The second transceiving path is coupled to the first transceiving path. The first wireless communications module is coupled to the first transceiving path and transmits or receives a plurality of first wireless signals. The second wireless communications module is coupled to the second transceiving path and transmits or receives a plurality of second wireless signals, wherein signal strengths of the second wireless signals passing through the second transceiving path are attenuated by a certain level, and the attenuated second wireless signals are added to the first wireless signals when passing through the first transceiving path.

Abstract: Systems and methods are provided for common mode testing for a system using an Ethernet subsystem. The Ethernet subsystem generates test signals that can be introduced at various points in the system to detect the effect of noise introduced by various elements of the system. By introducing test signals at various points in a system, common mode noise introduced into the system can be more accurately determined.

Abstract: A receiver includes a positive pulse determination circuit and a negative pulse determination circuit. The positive pulse determination circuit outputs a first L-level between when a pulse signal having a negative amplitude is detected and when neither a pulse signal having a positive amplitude nor a pulse signal having a negative amplitude is detected; otherwise a first H-level if a pulse signal having a positive amplitude is detected during another period. The negative pulse determination circuit outputs a second L-level between when a pulse signal having a positive amplitude is detected and when neither a pulse signal having a positive amplitude nor a pulse signal having a negative amplitude is detected; otherwise a second H-level is output if a pulse signal having a negative amplitude is detected during the other period.

Abstract: Power supply rejection in a single-ended receiver, through impedance balancing, is described. The single-ended receiver includes a first low noise amplifier and a second low noise amplifier. The single-ended receiver also includes a multi-port coupled transformer that outputs a differential signal. The multi-port coupled transformer includes a first primary coil that is coupled to an output of the first low noise amplifier and a second primary coil. The single-ended receiver also includes balancing impedances at the output of each of the low noise amplifiers. These impedances can be configured such that the on impedance of the first low noise amplifier equals the combined impedance of the off impedance of the second low noise amplifier and the balancing impedance. This balancing of impedances on the first and second primary coils results in power supply rejection of noise and spurious signals.

Abstract: A method for transmitting digital data via a line includes the steps of providing a clock signal and of transmitting the digital data in synchrony with the clock signal, the clock signal having a frequency that is variable over time.

Abstract: A communication system is disclosed for use with a train consist. The consist communication system may have a first fluid conduit, a first coupling connected to the first fluid conduit, a first cover connected to the first coupling and configured to close an end of the first fluid conduit, and at least a first cable disposed within the first fluid conduit. The system may also have a second fluid conduit substantially identical to the first fluid conduit, a second coupling substantially identical to the first coupling, fixedly connected to the second fluid conduit, and connectable to the first coupling, and a second cover connected to the second coupling and configured to close an end of the second fluid conduit. At least a second cable may be disposed within the second fluid conduit in communication with the at least a first cable through the first and second covers. The first and second fluid conduits may be pressurized.