General Instrument Corporation

Maxim Integrated Products, Inc.

Matthew Glenn Waight

Kevin T Chang

Yucheng Jin

Joel David Birkeland

Charles John Razzell

David Beryl Lazarus

James W Marsh

Frank Prestrelski

Dipakkumar R Patel

Alexei Shatalov

James D Rosemary

Howard Luong

Adam Heiberg

A communication system includes a first radio module and a second radio module. The first radio module includes a tuner communicatively coupled to a reference signal generator that is configured to generate a first reference signal for the tuner. The first radio module further includes a serializer configured to serialize a signal output by the tuner. The second radio module includes a deserializer configured to receive a serialized version of the signal from the serializer of the first radio module and deserialize the serialized version of the signal. The second radio module further includes a second tuner that is communicatively coupled to a clock recovery circuit. The clock recovery circuit is configured to generate a second reference signal for the second tuner based on a deserialized version of the first signal, where the second reference signal is frequency and phase locked to the first reference signal.

Remote tuner clock distribution using serializer/deserializer technology

An energy efficient, low distortion amplification apparatus includes: a differential amplifier having a pair of differential inputs, a pair of outputs, and a bias current control input; a digital delay having an n-bit word input and an m-bit word output; a digital-to-analog converter (DAC) having an input coupled to the output of the digital delay and a pair of differential outputs coupled to the pair of differential inputs of the differential amplifier; and a bias current controller having an input coupled to the digital delay and having an output coupled to the bias current control input of the differential amplifier.

Energy efficient, low distortion amplification apparatus

The present invention is an upstream power control system, within a cable modem which controls the power consumption of the cable modem. The power control system comprises a MAC chip which synchronizes upstream communication signals for transmission to a cable network and outputs an upstream control signal, an upstream amplifier which receives the synchronized upstream communication signals, and a complex programmable logic device (CPLD). The CPLD controls the upstream amplifier in response to the upstream control signal such that the upstream amplifier is powered on during transmission of the communication signals, and powered off when not transmitting, which results in the reduction of power consumed by the cable modem.

Dynamic upstream amplifier power management

A method and apparatus for an electronically tuned agile integrated bandpass filter is described. In one embodiment, the invention is an intermediate frequency filter for use in an integrated circuit. The filter includes a first filter stage, including a first LC resonator. The first filter stage further includes a first adjustable capacitor array coupled to the first LC resonator. The first adjustable capacitor array has an effective capacitance value adjustable through use of a first plurality of programmable data storage locations. The first plurality of programmable data storage locations are programmable through a serial control interface.

Electronically tuned agile integrated bandpass filter

A tunable receiver is disclosed including a plurality of select filters to perform an initial band selection, a variable-gain low noise amplifier (LNA) whose gain is controlled to prevent its output power level to exceed a pre-determined power threshold, a plurality of digitally-tunable tracking filters to pass signals within a selected channel and to reject signals in a corresponding image band, a second LNA to further amplify the received RF signal and to generate differential signal outputs, a down converting stage which converts the received RF signal to an IF signal while rejecting signals in the image band, an IF trap to further reject undesired signals present at the output of the down converting stage, an IF amplifier to amplify the IF signal to compensate for losses, an IF filter to provide channel select and reject undesirable signals, and a variable-gain IF amplifier to amplify the IF signal and maintain its power level within specification.

Broadband single conversion tuner integrated circuits

A modulator generates a combined signal consisting of audio and video signals and converts the combined signal to one of a plurality of frequencies in dependence upon a desired output frequency and broadcast standard. The modulator includes a summing amplifier, a first frequency synthesizer and a second frequency synthesizer. The summing amplifier has a first input for receiving a video signal, a second input for receiving a first audio signal, a third input for receiving a second audio signal, and an output for outputting a modulated summed signal. The first frequency synthesizer generates a first frequency for mixing with the modulated summed signal to generate a high intermediate frequency (HI-IF) signal. The second frequency synthesizer generates a second frequency for mixing with said HI-IF signal to generate a desired RF output signal.

Universal modulator

An arrangement for controlling multiple telephone lines terminating in a single residence uses a multiplexer within a communications gateway and a plurality of demultiplexers, each demultiplexer coupled to a separate one of telephone lines. The communications gateway functions to convert all received analog telephony signals into a digital format and then multiplexes the digital signals onto a single telephone line connected to the residence. The various telephone lines in the residence are connected in series along the line, using a number of drop-off points. The demultiplexer on each telephone line is configured to recognize the time slots within the multiplexed signal destined for its associated telecommunications device. In a similar fashion, separate time slots are assigned for upstream transmission from each telecommunication device into the HFC network.

Arrangement for managing multiple telephone lines terminating at a single location

An oscillator is formed using a Field-Effect Transistor (FET) in a Colpitts configuration. The circuit has a resistor from source to ground. Also connected to the source are two capacitors, one between the source and ground while the other is from source to gate. These capacitors provide a phase-shifted feedback signal to the gate. Also connected to the gate is the varactor tank, which has a voltage variable reactance that is used to tune the oscillation to the desired frequency. Between the drain of the FET and the supply voltage is a resistor-capacitor network. Between two series resistors a shunt capacitor is added to minimize local oscillator leakage onto the Vdd line. The resistor network also provides impedance for the Pre-Scalar output, which is simply a connection to the drain of the FET. The pre-scalar output is used to provide a reference signal to the phase-locked loop, which generates the correction voltage to the oscillator's VCO input. It is at the pre-scalar output that a filter network is added to reduce the base-band noise from the Vdd line. By adding a shunt network, consisting of a small inductor and a low ESR capacitor, the supply noise is filtered without reducing the voltage or current supplied to the oscillator. The inductor removes the shunt capacitance at the oscillation frequency, avoiding any reduction in signal to the phase-locked loop circuit. The low ESR capacitor works with the resistance on-chip between the Vdd line and the drain to reduce the low frequency noise present at the FET's drain. This reduction in low-frequency noise results in improved phase noise performance without degrading any other circuit parameters.

Low phase-noise voltage controlled oscillator

An improved multiple conversion CATV settop terminal eliminates the adverse effects of oscillator difference beats by selectively controlling local oscillators and the use of a wideband bandpass filter. The wideband bandpass filter is coupled between the output of an up converter mixer and the input of a down converter mixer. Each mixer receives a second input from its corresponding local oscillator. A system microprocessor is programmed to control each local oscillator such that the oscillator difference beat frequencies are translated out of a following IF filter passband. Once translated, the oscillator difference beat frequencies no longer present a source of distortion to the received information signal.

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Pipersville, PA, United States of America

Matthew Glenn Waight