Abstract: Removing common-mode current from a pair of complementary current signals, including: generating a common-mode voltage of the pair of complementary current signals including at least a first current signal and a second current signal; measuring and outputting a difference voltage between the generated common-mode voltage and a common-mode reference voltage; and removing at least a portion of the common-mode current from the first current signal and the second current signal based on the difference voltage.

Abstract: A method, an apparatus, and a computer program product are provided. The apparatus may be a regulator circuit. The regulator circuit includes a first voltage regulator to regulate a first input voltage to the first voltage regulator, the first voltage regulator including a P-type metal-oxide-semiconductor (PMOS), and a second voltage regulator to regulate a second input voltage to the second voltage regulator, the second voltage regulator including an N-type metal-oxide-semiconductor (NMOS). In an aspect, the first voltage regulator is coupled to the second voltage regulator.

Abstract: Techniques for calibrating a receiver based on a local oscillator (LO) signal from another receiver are disclosed. In an exemplary design, an apparatus (e.g., a wireless device or an integrated circuit) includes first and second local oscillator (LO) generators. The first LO generator generates a first LO signal used by a first receiver for frequency downconversion. The second LO generator generates a second LO signal used by a second receiver for frequency downconversion in a first operating mode. The second LO signal is used to generate a test signal for the first receiver in a second operating mode. The second LO signal may be provided as the test signal or may be amplitude modulated with a modulating signal to generate the test signal. The test signal may be used to calibrate residual sideband (RSB), second order input intercept point (IIP2), receive path gain, etc.

Abstract: Exemplary embodiments are directed to impedance balancing within a transceiver. A device may include a transformer having a first side coupled to a transmit path and a second side coupled to a receive path. Further, the device may include an antenna tuning network coupled to a first portion of the first side and configured for coupling to an antenna. The device may also include an adjustment unit coupled to a second portion of the first side and configured for being adjusted to enable an impedance at the adjustment unit to be substantially equal to an impedance at the antenna tuning network.

Abstract: A multi-mode receiver is disclosed that is reconfigurable to share a local oscillator signal in diversity mode to save power consumption. In an exemplary embodiment, an apparatus includes a primary receiver having a primary mixer configured to down-convert a primary signal and a secondary mixer configured to down-convert a secondary signal in carrier aggregation mode. The apparatus also includes a supplemental mixer that uses a shared primary local oscillator (LO) signal generated by a shared primary frequency synthesizer in diversity mode to reduce power consumption. The apparatus further includes a controller configured to disable the secondary mixer and to enable the supplemental mixer to down-convert the secondary signal when operating in the diversity mode.

Abstract: Certain aspects of the present disclosure provide methods and apparatus for generating local oscillator (LO) signals for multiple receive chains. One example circuit for generating first and second signals generally includes a first voltage controlled oscillator (VCO) configured to output the first signal at a first frequency and associated with a first receive chain for receiving a first carrier of an aggregated resource; and a second VCO configured to output the second signal at a second frequency and associated with a second receive chain for receiving a second carrier of the aggregated resource. The second frequency is different than the first frequency. In this manner, pulling or coupling between the two VCOs may be avoided, even if the two VCOs are implemented on the same radio frequency integrated circuit (RFIC).

Abstract: Selectable sizes for a local oscillator (LO) buffer and mixer are disclosed. In an exemplary embodiment, LO buffer and/or mixer size may be increased when a receiver or transmitter operates in a high gain mode, while LO buffer and/or mixer size may be decreased when the receiver or transmitter operates in a low gain mode. In an exemplary embodiment, LO buffer and mixer sizes are increased and decreased in lock step. Circuit topologies and control schemes for specific exemplary embodiments of LO buffers and mixers having adjustable size are disclosed.

Abstract: A time-to-digital converter (TDC) with fine resolution of less than one inverter delay is described. In an exemplary design, the TDC includes first and second delay paths, a delay unit, and a phase computation unit. The first delay path receives a first input signal and a first reference signal and provides a first output. The second delay path receives a second input signal and a second reference signal and provides a second output. The delay unit delays the second input signal relative to the first input signal or delays the second reference signal relative to the first reference signal, e.g., by one half inverter delay. The phase computation unit receives the first and second outputs and provides a phase difference between the input signal and the reference signal. Calibration may be performed to obtain accurate timing for the first and second delay paths.

Abstract: A method for reducing power consumption on a wireless communication device is described. The wireless communication device includes a first stage active filter and a second stage active filter. A condition measurement is obtained that includes a signal measurement condition. If it is determined that the condition measurement is above a threshold, the second stage active filter is bypassed.

Abstract: A method for reducing power consumption on a wireless communication device is described. The wireless communication device includes a first stage active filter and a second stage active filter. A condition measurement is obtained that includes a signal measurement condition. If it is determined that the condition measurement is above a threshold, the second stage active filter is bypassed.

Abstract: Exemplary embodiments are related to enhancing power efficiency of an electronic device. A device may include a power management module and a radio-frequency (RF) module coupled to the power management module. The device may further include a digital module coupled to each of the power management module and the RF module and configured to dynamically adjust at least one setting of the power management module based on one or more RF conditions.

Abstract: A method for reducing average current consumption in a local oscillator (LO) path is disclosed. An LO signal is received at a master frequency divider and a slave frequency divider. Output from the master frequency divider is mixed with an input signal to produce a first mixed output. Output from the slave frequency divider is mixed with the input signal to produce a second mixed output. The second mixed output is forced to be in phase with the first mixed output.

Abstract: A method and apparatus for providing an oscillating signal within a transmitter/receiver circuit is described. The transmitter/receiver circuit may include an oscillator that generates an oscillating signal that may be provided to a low power, low gain mixer of the transmitter/receiver circuit along a shorter circuit path that includes low power circuitry, such as low power buffers and low power frequency dividers. The oscillating signal may also be provided to a high power, high gain mixer along a longer circuit path that includes high power circuitry, such as high power buffers and high power frequency dividers. Specifically, the low power circuitry is adapted to consume less power in an ON state than the high power circuitry in an ON state, and the shorter circuit path has a shorter electrical path length than the longer circuit path.

Abstract: A multi-mode receiver is disclosed that is reconfigurable to share a local oscillator signal in diversity mode to save power consumption. In an exemplary embodiment, an apparatus includes a primary receiver having a primary mixer configured to down-convert a primary signal and a secondary mixer configured to down-convert a secondary signal in carrier aggregation mode. The apparatus also includes a supplemental mixer that uses a shared primary local oscillator (LO) signal generated by a shared primary frequency synthesizer in diversity mode to reduce power consumption. The apparatus further includes a controller configured to disable the secondary mixer and to enable the supplemental mixer to down-convert the secondary signal when operating in the diversity mode.

Abstract: Techniques for calibrating a receiver based on a local oscillator (LO) signal from another receiver are disclosed. In an exemplary design, an apparatus (e.g., a wireless device or an integrated circuit) includes first and second local oscillator (LO) generators. The first LO generator generates a first LO signal used by a first receiver for frequency downconversion. The second LO generator generates a second LO signal used by a second receiver for frequency downconversion in a first operating mode. The second LO signal is used to generate a test signal for the first receiver in a second operating mode. The second LO signal may be provided as the test signal or may be amplitude modulated with a modulating signal to generate the test signal. The test signal may be used to calibrate residual sideband (RSB), second order input intercept point (IIP2), receive path gain, etc.

Abstract: A receiver architecture for carrier aggregation is disclosed. In an exemplary design, an apparatus (e.g., a wireless device, a circuit module, etc.) includes a plurality of low noise amplifiers (LNAs), a plurality of switches, and at least one downconverter. The LNAs receive and amplify at least one input radio frequency (RF) signal and provide at least one amplified RF signal. The switches are coupled to the outputs of the plurality of LNAs. The at least one downconverter is coupled to the plurality of switches, downconverts the at least one amplified RF signal, and provides at least one downconverted signal. The switches reduce the number of downconverters needed to support reception of transmissions on multiple sets of carriers via multiple receive antennas. The LNAs and the switches may be implemented on at least one front-end module or a back-end module. The downconverter(s) are implemented on the back-end module.

Abstract: A method and apparatus for providing an oscillating signal within a transmitter/receiver circuit is described. The transmitter/receiver circuit may include an oscillator that generates an oscillating signal that may be provided to a low power, low gain mixer of the transmitter/receiver circuit along a shorter circuit path that includes low power circuitry, such as low power buffers and low power frequency dividers. The oscillating signal may also be provided to a high power, high gain mixer along a longer circuit path that includes high power circuitry, such as high power buffers and high power frequency dividers. Specifically, the low power circuitry is adapted to consume less power in an ON state than the high power circuitry in an ON state, and the shorter circuit path has a shorter electrical path length than the longer circuit path.

Abstract: An exemplary embodiment disclosed comprises a mixer having a plurality of input leads; a first degenerative impedance element coupled to a first input lead of the mixer; a second degenerative impedance element coupled to a second input lead of the mixer; and a local oscillator (LO) system comprising a plurality of duty cycle modes to generate a LO signal for the mixer, the local oscillator system operates in a first duty cycle based on a first gain state of the mixer, and in a second duty cycle based on a second gain state of the mixer.

Abstract: Techniques are provided for reducing mismatch between the in-phase (I) and quadrature (Q) channels of a communications transmitter or receiver. In an exemplary embodiment, separate voltages are applied to bias the gates or bulks of the transistors in a mixer of the I channel versus a mixer of the Q channel. In another exemplary embodiment, separate voltages are applied to bias the common-mode reference voltage of a transimpedance amplifier associated with each channel. Techniques are further provided for deriving bias voltages to minimize a measured residual sideband in a received or transmitted signal, or to optimize other parameters of the received or transmitted signal. Techniques for generating separate bias voltages using a bidirectional and unidirectional current digital-to-analog converter (DAC) are also disclosed.

Abstract: Techniques are provided for reducing mismatch between the in-phase (I) and quadrature (Q) channels of a communications transmitter or receiver. In an exemplary embodiment, separate voltages are applied to bias the gates or bulks of the transistors in a mixer of the I channel versus a mixer of the Q channel. In another exemplary embodiment, separate voltages are applied to bias the common-mode reference voltage of a transimpedance amplifier associated with each channel. Techniques are further provided for deriving bias voltages to minimize a measured residual sideband in a received or transmitted signal, or to optimize other parameters of the received or transmitted signal. Techniques for generating separate bias voltages using a bidirectional and unidirectional current digital-to-analog converter (DAC) are also disclosed.