Abstract: Examples of circuits and methods are provided for common mode stability and bandwidth broadening. A current generator circuit may include a first and a second transistor. Each of the first and second transistors includes a first, second, and third terminal. The first and second transistors provide a first and a second output current at their corresponding third terminals. A first branch including a first resistor and a first capacitor coupled in series is coupled between the third terminal of the first transistor and the first terminal of the second transistor. A second branch including a second resistor and a second capacitor coupled in series is coupled between the third terminal of the second transistor and the first terminal of the first transistor. The first and the second branches are configured to enable the current generator circuit to provide the first and second currents with improved common mode stability.

Abstract: An example of a radio frequency (RF) transmitter system for communication may include a transmit pre-distortion module configured to provide a second transmit calibration signal during a transmit calibration mode based on a first transmit calibration signal and one or more transmit calibration adjustment signals. The one or more transmit calibration adjustment signals may include an offset parameter associated with DC offset and an imbalance parameter associated with at least one of gain and phase imbalances. The system may include a transmit channel frequency converter coupled to the transmit pre-distortion module. The transmit channel frequency converter may be configured to provide a fourth transmit calibration signal during the transmit calibration mode based on a third transmit calibration signal and a transmit reference signal.

Abstract: An example of a method for off-line calibration of a radio frequency (RF) communication system may include one or more of the following: enabling an off-line calibration mode for an RF communication system; generating an off-line calibration signal; applying to a frequency converter a first off-line calibration signal corresponding to the generated off-line calibration signal; translating the first off-line calibration signal into a second off-line calibration signal; evaluating one or more calibration adjustment signals associated with the calibration signal to reduce error in the communication system, wherein the one or more calibration adjustment signals may include an offset parameter associated with DC offset and an imbalance parameter associated with at least one of gain and phase imbalances; storing one or more calibration adjustment signals; disabling the off-line calibration mode; applying a communication signal; and adjusting the communication signal based on the stored one or more calibration adjus

Abstract: An example of a radio frequency (RF) receiver system for communication may include a receive channel frequency converter configured to provide a second receive calibration signal during a receive calibration mode based on a first receive calibration signal and a receive reference signal. The system may include a receive pre-distortion module coupled to the receive channel frequency converter. The receive pre-distortion module may be configured to provide a fourth receive calibration signal during the receive calibration mode based on a third receive calibration signal and one or more receive calibration adjustment signals. The one or more receive calibration adjustment signals may comprise an offset parameter associated with DC offset and an imbalance parameter associated with at least one of gain and phase imbalances.

Abstract: High-speed, high-performance, low-power transponders, serializers and deserializers are disclosed. A serializer may include a serdes framer interface (SFI) circuit, a clock multiplier unit, and a multiplexing circuit. A deserializer may include an input receiver circuit for receiving and adjusting an input data signal, a clock and data recovery circuit (CDR) for recovering clock and data signals, a demultiplexing circuit for splitting one or more data channels into a higher number of data channels, and a serdes framer interface (SFI) circuit for generating a reference channel and generating output data channels to be sent to a framer. The input receiver circuit may include a limiting amplifier. Each of the serializer and deserializer may further include a pseudo random pattern generator and error checker unit. The serializer and deserializer each may be integrated into its respective semiconductor chip or both may be integrated into a single semiconductor chip.

Abstract: A channelization filter communication system comprises: a channelization filtering system, a calibration unit, amplifiers, communication channel frequency converters and a baseband processor. The channelization filtering system includes a selector input configured to receive a communication channel filter selector signal and selectable communication channel filter elements. The selectable communication channel filter elements include one or more resistors formed of a first resistor type and one or more capacitors formed of a first capacitor type. The calibration unit includes a calibration signal generator configured to provide a calibration signal and a frequency measurement unit. The calibration signal generator includes one or more resistors formed of the same first resistor type and one or more capacitors formed of the same first capacitor type.

Abstract: A video switching and control system is described that provides compatibility with conventional analog cameras while also accepting network IP type cameras. The system offers reduced control latency, improved recording efficiency, and more flexible display features with greatly improved performance and update rates. The system offers greatly reduced wiring and installation complexity thus improving reliability. The architecture is scalable and expandable in either the analog camera count or the IP camera count. The system integrates these two camera technologies so that the camera source or recorder is transparent to the user. Each user can control all video sources, analog, IP, or recorded, from one keyboard and one or more monitors at each work station. The unique all digital solution provides digital reliability and broadcast quality performance.

Abstract: An example of a method for off-line calibration of a radio frequency (RF) communication system may include one or more of the following: enabling an off-line calibration mode for an RF communication system; generating an off-line calibration signal; applying to a frequency converter a first off-line calibration signal corresponding to the generated off-line calibration signal; translating the first off-line calibration signal into a second off-line calibration signal; evaluating one or more calibration adjustment signals associated with the calibration signal to reduce error in the communication system, wherein the one or more calibration adjustment signals may include an offset parameter associated with DC offset and an imbalance parameter associated with at least one of gain and phase imbalances; storing one or more calibration adjustment signals; disabling the off-line calibration mode; applying a communication signal; and adjusting the communication signal based on the stored one or more calibration adjus

Abstract: An example of a radio frequency (RF) receiver system for communication may include a receive channel frequency converter configured to provide a second receive calibration signal during a receive calibration mode based on a first receive calibration signal and a receive reference signal. The system may include a receive pre-distortion module coupled to the receive channel frequency converter. The receive pre-distortion module may be configured to provide a fourth receive calibration signal during the receive calibration mode based on a third receive calibration signal and one or more receive calibration adjustment signals. The one or more receive calibration adjustment signals may comprise an offset parameter associated with DC offset and an imbalance parameter associated with at least one of gain and phase imbalances.

Abstract: An example of a radio frequency (RF) transmitter system for communication may include a transmit pre-distortion module configured to provide a second transmit calibration signal during a transmit calibration mode based on a first transmit calibration signal and one or more transmit calibration adjustment signals. The one or more transmit calibration adjustment signals may include an offset parameter associated with DC offset and an imbalance parameter associated with at least one of gain and phase imbalances. The system may include a transmit channel frequency converter coupled to the transmit pre-distortion module. The transmit channel frequency converter may be configured to provide a fourth transmit calibration signal during the transmit calibration mode based on a third transmit calibration signal and a transmit reference signal.

Abstract: A radio frequency transceiver for off-line transmit and receive calibrations includes: a transmit pre-distortion module configured to receive a transmit calibration signal during a transmit calibration mode, a transmit communication signal during a transmit communication operation mode, and one or more transmit calibration adjustment signals; a transmit channel frequency converter; and a transmit calibration module configured to provide the one or more transmit calibration adjustment signals and the transmit calibration signal to the transmit pre-distortion module.

Abstract: A communication system includes a multiplexer configured to multiplex a first set of data channels into a first data channel and to multiplex a second set of data channels into a second data channel, and a delay adjuster configured to adjustably delay the first data channel based on a delay adjust command. The communication system also includes a first amplifier configured to amplify the delayed first channel into a first output data channel, and a second amplifier configured to amplify the second data channel into a second output data channel. The communication system further includes a first driver configured to convert the first output data channel into a first drive signal to drive an optical modulator, and a second driver configured to convert the second output data channel into a second drive signal to drive the optical modulator.

Abstract: A channelization filter communication system comprises: a channelization filtering system, a calibration unit, amplifiers, communication channel frequency converters and a baseband processor. The channelization filtering system includes a selector input configured to receive a communication channel filter selector signal and selectable communication channel filter elements. The selectable communication channel filter elements include one or more resistors formed of a first resistor type and one or more capacitors formed of a first capacitor type. The calibration unit includes a calibration signal generator configured to provide a calibration signal and a frequency measurement unit. The calibration signal generator includes one or more resistors formed of the same first resistor type and one or more capacitors formed of the same first capacitor type.

Abstract: A radio frequency transceiver for off-line transmit and receive calibrations includes: a transmit pre-distortion module configured to receive a transmit calibration signal during a transmit calibration mode, a transmit communication signal during a transmit communication operation mode, and one or more transmit calibration adjustment signals; a transmit channel frequency converter; and a transmit calibration module configured to provide the one or more transmit calibration adjustment signals and the transmit calibration signal to the transmit pre-distortion module.

Abstract: An integrated circuit includes a serdes framer interface (SFI) circuit for receiving a first set of data channels and a reference channel, generating first logic levels for the first set of data channels, and realigning the first set of data channels relative to a reference channel. The integrated circuit further includes a multiplexing circuit for receiving a second set of data channels and for merging the second set of data channels into one or more data channels. The second set of data channels is generated based on the first set of data channels. A data rate of the one or more data channels is higher than a data rate of the second set of data channels.

Abstract: A communication system includes a front-end multi-throw switch, a back-end multi-throw switch, multiple filters and a switch controller. The front-end multi-throw switch includes front-end throws and a front-end pole. The front-end pole is coupled to a receive channel or a transmit channel. The front-end pole is switchably coupled to one of the front-end throws. The back-end multi-throw switch includes back-end throws and a back-end pole. Each of the back-end throws is associated with a corresponding one of the front-end throws. The back-end pole is coupled to the receive channel or the transmit channel. The back-end pole is switchably coupled to one of the back-end throws. The one of the back-end throws corresponds to the one of the front-end throws. The filters are interposed between the front-end multi-throw switch and the back-end multi-throw switch. Each of the filters has a first port coupled to one of the front-end throws and a second port coupled to one of the back-end throws.

Abstract: A multi-channel filtering system for use with a transceiver includes a front-end multi-pole, multi-throw switch, a back-end multi-pole, multi-throw switch, and a plurality of filters. The front-end switch includes a receive pole, a transmit pole, and a plurality of switch throws. The back-end switch also includes a receive pole, a transmit pole, and a plurality of switch throws. Each of the plurality of filters has first and second ports, each first port coupled to one of the switch throws of the front-end switch, and each second port coupled to one of the switch throws of the back-end switch. Using this configuration, filters of differing bandwidths can be switched in during signal reception and/or transmission, thereby tailoring the communication rate to the particular conditions.

Abstract: A precision timing generator includes a combiner that provides a timing signal by combining a coarse timing signal and a fine timing signal derived from a phase-shifted sinusoidal signal that has a desired phase shift. The coarse timing generator generates the coarse timing signal from a clock signal and a timing command input. The fine timing generator includes a sinusoidal-signal generator that receives the clock signal and generates a sinusoidal signal. The fine timing generator also includes a phase shifter that receives the sinusoidal signal and the timing command input and shifts the phase of the sinusoidal signal based on the timing input to generate the phase shifted sinusoidal signal.

Abstract: A baseband signal converter device for an impulse radio receiver combines multiple converter circuits and an RF amplifier in a single integrated circuit package. Each converter circuit includes an integrator circuit that integrates a portion of each RF pulse during a sampling period triggered by a timing pulse generator. The integrator capacitor is isolated by a pair of Schottky diodes connected to a pair of load resistors. A current equalizer circuit equalizes the current flowing through the load resistors when the integrator is not sampling. Current steering logic transfers load current between the diodes and a constant bias circuit depending on whether a sampling pulse is present.

Abstract: Methods and apparatus for providing connection packages for high-speed integrated circuits (“ICs”) in optical, electronic, wired or wireless communications are disclosed. The connection package achieves dimensional transformation of signal routes from high-speed, high-density IC's input/output pads to the external terminals such as coaxial terminals and BGA balls, while maintaining constant characteristic impedance throughout the transmission lines. A package may include a substrate having microstrips for communicating signals between the IC pads and external terminals. A pair of differential microstrips can be positioned closer to each other near the IC pads and create capacitive coupling. Such coupled capacitance allows the width of the microstrips to be reduced.