Qualcomm Incorporated

Analog Devices,inc.

Analog Devices Global

Analog Devices Technology

Analog Devices Global Unlimited Company

Kevin Glenn Gard

Charles James Persico

Antonio J Montalvo

Anthony Segoria

Gurkanwal (Kamal) Sahota

Gurkanwal Singh Sahota

Christopher Mayer

Brett Christopher Walker

Kenneth Charles Barnett

Trevor Clifford Caldwell

David Nelson Alldred

Zhao Li

Victor Kozlov

David J Mclaurin

Shipra Bhal

Raju Hormis

Jeremy Darren Dunworth

Steven C Ciccarelli

David J Maldonado

Paul E Peterzell

Puay Hoe See

David J McLaurin

Steven R Bal

Jianxun Fan

Robert C Glenn

Shinichi Miyazaki

David Alldred

Embodiments of the present invention may provide a receiver. The receiver may include an RF section, a local oscillation signal generator to generate quadrature local oscillation signals, and a quadrature mixture, coupled to the RF section, to downconvert a first group of wireless signals directly to baseband frequency quadrature signals and to downconvert a second group of wireless signals to intermediate frequency quadrature signals. The receiver may also include a pair of analog-to-digital converters (ADCs) to convert the downconverted quadrature signals to corresponding digital quadrature signals. Further, the receiver may include a digital section having two paths to perform signal processing on the digital baseband frequency quadrature signals and to downconvert the digital intermediate frequency signals to baseband cancelling a third order harmonic distortion therein. Moreover, the receiver may include a phase corrector to adjust a phase of one of the local oscillation signals to balance the third order harmonic distortion and a gain offset generator to adjust a gain of one of the downconverted signals to balance the third order harmonic distortion.

Multi-carrier base station receiver

Aspects of this disclosure relate to compensating for an offset in a receiver. In one embodiment, the receiver comprises a mixer, a feedback amplifier, and an offset correction circuit. The offset correction circuit can generate an indication of an offset in a differential input to the feedback amplifier and apply an offset compensation signal at an offset compensation node. The offset compensation node can be in a signal path of the feedback amplifier. Such offset compensation can reduce or eliminate leakage from a local oscillator at an input port of the mixer and/or at an antenna port of the receiver.

Offset compensation in a receiver

A transmission module is provided that includes a transmitter, a loopback receiver, and a QEC controller. In a first state, the QEC controller calibrates the loopback receiver to remove quadrature imbalance in the loopback receiver. In a second state, a communication pathway is provided between the transmitter and the loopback receiver, and the QEC controller identifies quadrature imbalance in the transmitter based at least one a comparison of the data signals at the output of the loopback receiver with data signals at the input of the transmitter. Based on the comparison, the QEC controller can adjust one or more characteristics of the transmitter to correct quadrature errors in the transmitter.

Wideband quadrature error correction

Embodiments of the present invention may provide a receiver. The receiver may include an RF section and a quadrature mixture, coupled to the RF section, to downconvert a first group of wireless signals directly to baseband frequency quadrature signals and to downconvert a second group of wireless signals to intermediate frequency quadrature signals. The receiver may also include a pair of analog-to-digital converters (ADCs) to convert the downconverted quadrature signals to corresponding digital quadrature signals. Further, the receiver may include a digital section having two paths to perform signal processing on the digital baseband frequency quadrature signals and to downconvert the digital intermediate frequency signals to baseband cancelling a third order harmonic distortion therein. The receiver may be provided on a monolithically integrated circuit.

A calibration system for an analog-to-digital converter (ADC) an internal ADC that receives an analog input and converts the analog input to digital multi-bit data. The calibration system also includes a reference shuffling circuit that shuffles reference values of comparators of the internal ADC. Further, the calibration system includes a calibration circuit that calibrates the comparators of the internal ADC. The calibration system includes a digital block that measures an amplitude based on the digital multi-bit data. Additionally, the calibration system includes calibration logic that controls the calibration circuit based on an output of the digital block.

System, method and recording medium for analog to digital converter calibration

A low-power diversity receiver includes at least two receive paths, each of which is designated as a primary or secondary receive path. A primary receive path is compliant with system requirements (e.g., IS-98D requirements). A secondary receive path is not fully compliant with the system requirements and is designed for lower power, less area, and lower cost than the primary receive path. For a multi-antenna receiver, the two receive paths may be used to simultaneously process two received signals from two antennas. For a single-antenna receiver, either the primary or secondary receive path is selected, e.g., depending on whether or not large amplitude 'jammers' are detected, to process a single input signal from one antenna. The receiver may include additional receive paths for additional frequency bands and/or GPS.

Low-power wireless diversity receiver with multiple receive paths

Techniques to reduce LO leakage by controlling the amplitude of LO signal based on the level of output signal after the frequency conversion process. An LO generator receives a VCO signal and generates an LO signal having a variable amplitude and a frequency that is related to the frequency of the VCO signal. A variable gain amplifier receives a control signal and adjusts the amplitude of the LO signal based on the control signal. The variable amplitude LO signal is used for frequency upconversion (e.g., direction upconversion) of an input signal (e.g., at baseband) to obtain an output signal (e.g., at RF). The relationship between LO signal amplitude and output signal level may be defined by a particular transfer function. In general, the LO signal is set higher for higher output signal level and is reduced proportionally for lower output signal level.

Direct conversion with variable amplitude LO signals

A radio frequency (RF) driver amplifier system and method that provides linear in decibel gain control is provided. The RF driver amplifier system comprises a linear transconductor receiving an input voltage and providing a controlled current based on input voltage received, temperature compensation circuitry for varying current from the linear transconductor according to absolute temperature, an exponential current controller receiving current varied according to temperature and providing an exponential current in response, and an inductive degeneration compensator receiving exponential current and providing a control current to driver amplifier circuitry, thereby compensating for inductive degeneration due to at least one inductor in the driver amplifier circuitry. Control current passes from the inductive degeneration compensator to the driver amplifier circuitry. Output gain from the driver amplifier circuitry varies linearly in decibels with respect to the input voltage.

Continuously variable gain radio frequency driver amplifier having linear in decibel gain control characteristics

A system and method for generating a local oscillator (LO) frequency in a zero intermediate frequency (IF) receiver or transmitter is presented. A signal is received from a voltage controlled oscillator (VCO). The signal has a VCO frequency. The VCO frequency is divided by a number N to produce a signal having a divided-down frequency. The signal having the VCO frequency is then mixed with the signal having the divided-down frequency to produce an output signal having an output frequency. Local oscillator leakage is reduced. Thus, the receiver or transmitter may operate in multiple wireless communication bands and modes and meet the associated specifications.

Local oscillator leakage control in direct conversion processes

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Raleigh, NC, United States of America

Kevin Glenn Gard