Abstract: Certain aspects provide a method for object detection. The method generally includes: transmitting, via a first antenna, a transmit signal generated via a first transmit chain, the transmit signal being generated based on a mixer output signal; receiving a first receive signal via a first receive chain coupled to a second antenna, the first receive signal being associated with the transmit signal; generating, via a first phase shifter, a first phase-shifted signal based on an adjustment signal received via a signal path coupled to the first transmit chain, the adjustment signal being generated based on the mixer output signal; combining the first phase-shifted signal and the first receive signal to generated a combined receive signal, wherein a phase-shift setting of the first phase shifter is controlled based on at least one of a mutual coupling component or a phase noise of the combined receive signal.

Abstract: A radio frequency integrated circuit (RFIC), including a power amplifier (PA) connected to an antenna through a first electromagnetic (EM) element, the PA configured to receive a transmit signal from a second EM element, a low noise amplifier (LNA) connected to the first EM element and the second EM element, the power amplifier and the LNA comprising separate amplifier cores, and wherein the first EM element comprises a first plurality of interwound windings occupying a first common area and the second EM element comprises a second plurality of interwound windings occupying a second common area.

Abstract: A phase shifter having an input matching network, a vector modulator connected to the input matching network, the vector modulator configured to alter an amplitude of signals provided by the input matching network, bias networks coupled to outputs of the vector modulator, and a combining circuit connected to the outputs of the vector modulator, the combining circuit configured to generate a first phase (?1) signal from the outputs of the vector modulator.

Abstract: Certain aspects provide a method for wireless communication by a device. The method generally includes: transmitting a transmit signal via a first antenna; receiving a first receive signal via a second antenna and a second receive signal via a third antenna, the first receive signal and the second receive signal being associated with the transmit signal; generating a first phase-shifted signal via a first phase shifter based on the first receive signal, and a second phase-shifted signal via a second phase shifter based on the second receive signal; and combining the first phase-shifted signal and the second phase-shifted signal to generate a combined receive signal, wherein a phase-shift setting of at least one of the first phase shifter or the second phase shifter is controlled based on at least one of a mutual coupling component or a phase noise of the combined receive signal.

Abstract: Certain aspects of the present disclosure are directed towards apparatus and techniques for receiver calibration. An example apparatus generally includes: a first receiver having a first oscillating signal generation circuit, an output of the first oscillating signal generation circuit being coupled to an input of a first splitter, wherein the first splitter has multiple outputs; a second receiver having a second oscillating signal generation circuit coupled to an LO input of each of a first plurality of mixers of the second receiver; and signal paths between the multiple outputs of the first splitter and signal inputs of the first plurality of mixers, respectively.

Abstract: A phase shifter for a millimeter wave (mmW) communication system including an in phase variable gain amplifier (I VGA) and a quadrature VGA (Q VGA) configured to receive radio frequency (RF) signals, the I VGA and the Q VGA configured to provide a selectable output to primary sides of first and second electromagnetic (EM) elements, respectively, the first EM element configured to provide a single-ended I output and the second EM element configured to provide a single-ended Q output, and a hybrid quadrature generator (HQG) configured to receive the single-ended I output of the first EM element and the single-ended Q output of the second EM element, the HQG configured to provide a combined signal at a desired phase.

Abstract: Aspects of the disclosure relate to a radio frequency phase shifter. An example includes an amplification stage to produce an amplified voltage, the amplification stage having a first amplifier with a first input coupled to a first output of a hybrid coupler and a second amplifier with a complementary second input coupled to a complementary second output of the hybrid coupler. A vector modulation stage coupled to the amplification stage receives the amplified voltage and produces a modulated vector, the vector modulation stage has an in-phase section and a quadrature section to control the phase of the modulated vector in response to a phase control signal. A varactor coupled across the first input and the second input of the amplification stage adjusts the capacitance between the first input and the second input in response to a capacitance control signal.

Abstract: Aspects of the disclosure relate to devices, wireless communication apparatuses, methods, and other aspects of spur suppression in millimeter wave receivers. In one aspect a local oscillator (LO) source is coupled to a quadrature generation circuit having a first output for a first LO signal, and a second output for a second LO signal 90 degrees out of phase with the first LO signal. Each output is coupled to an LO driver, and outputs of the LO drivers a coupled at a first power connection to provide spur suppression associated with a phase difference between the first LO signal and the second LO signal. Similar connections are provided at outputs of first and second mixers for spur suppression.

Abstract: Methods and apparatus for calibration of a second-order input intercept point (IIP2) of a mixer, such as a mixer in a wireless receive chain. One example circuit for mixer IIP2 calibration generally includes a first receive chain comprising a first mixer and a single tone generator having an output coupled to an input of the first mixer and configured to generate a calibration signal having a single baseband tone. One example method of mixer IIP2 calibration generally includes generating a calibration signal comprising a single baseband tone, applying the calibration signal to an input of a mixer, such that the mixer generates a differential tone at an output of the mixer, and adjusting the mixer to minimize a power of the differential tone at the output of the mixer.

Abstract: An example apparatus includes a polyphase transconductance-capacitor filter. The polyphase filter includes a DC bias voltage node, a plus in-phase filter unit, a minus in-phase filter unit, a plus quadrature-phase filter unit, and a minus quadrature-phase filter unit. Each filter unit respectively includes an input node, an output node, and a control node. The polyphase filter also includes a plus in-phase switch and a minus in-phase switch. The plus in-phase switch is coupled to the control node of the plus in-phase filter unit, the DC bias voltage node, and the input node of one or both of the plus quadrature-phase filter unit and the minus quadrature-phase filter unit. The minus in-phase switch is coupled to the control node of the minus in-phase filter unit, the DC bias voltage node, and the input node of one or both of the plus quadrature-phase filter unit and the minus quadrature-phase filter unit.

Abstract: Aspects of the disclosure relate to a radio frequency phase shifter. An example includes an amplification stage to produce an amplified voltage, the amplification stage having a first amplifier with a first input coupled to a first output of a hybrid coupler and a second amplifier with a complementary second input coupled to a complementary second output of the hybrid coupler. A vector modulation stage coupled to the amplification stage receives the amplified voltage and produces a modulated vector, the vector modulation stage has an in-phase section and a quadrature section to control the phase of the modulated vector in response to a phase control signal. A varactor coupled across the first input and the second input of the amplification stage adjusts the capacitance between the first input and the second input in response to a capacitance control signal.

Abstract: An apparatus is disclosed for phase-shifting signals. In example implementations, the apparatus includes a phase shifter. The phase shifter includes a first port, a second port, a vector modulator coupled to the first port, and a signal phase generator. The signal phase generator includes multiple amplifiers coupled between the vector modulator and the second port. The signal phase generator also includes multiple capacitors that couple the multiple amplifiers together to form a loop. Each respective capacitor of the multiple capacitors is coupled between a respective pair of consecutive amplifiers of the multiple amplifiers to form the loop.

Abstract: An example apparatus includes a polyphase transconductance-capacitor filter. The polyphase filter includes a DC bias voltage node, a plus in-phase filter unit, a minus in-phase filter unit, a plus quadrature-phase filter unit, and a minus quadrature-phase filter unit. Each filter unit respectively includes an input node, an output node, and a control node. The polyphase filter also includes a plus in-phase switch and a minus in-phase switch. The plus in-phase switch is coupled to the control node of the plus in-phase filter unit, the DC bias voltage node, and the input node of one or both of the plus quadrature-phase filter unit and the minus quadrature-phase filter unit. The minus in-phase switch is coupled to the control node of the minus in-phase filter unit, the DC bias voltage node, and the input node of one or both of the plus quadrature-phase filter unit and the minus quadrature-phase filter unit.

Abstract: A transformer-based antenna switching network includes a transformer having a secondary winding that extends between a first terminal and a second terminal. The first terminal couples to ground through a first switch and connects to a first antenna. The second terminal couples to ground through a second switch and connects to a second antenna.

Abstract: In certain aspects, a receiver includes first amplifiers, wherein each one of the first amplifiers comprises an input and an output. The receiver also includes second amplifiers, wherein each one of the second amplifiers comprises an input and an output, and the outputs of the second amplifiers are coupled to a combining node. The receiver also includes transmission lines, wherein each one of the transmission lines is coupled between the output of a respective one of the first amplifiers and the input of a respective one of the second amplifiers. The receiver further includes a load coupled to the combining node, and receiver elements, wherein each one of the receiver elements comprises an input and an output, and the output of each one of the receiver elements is coupled to the input of a respective one of the first amplifiers.

Abstract: An apparatus is disclosed for phase-shifting signals with a compensation circuit. In example implementations, an apparatus for phase-shifting signals includes a phase shifter having a first port and a second port. The phase shifter also includes a signal phase generator, a compensation circuit, and a vector modulator. The compensation circuit includes a first capacitor with a first capacitance and a second capacitor with a second capacitance. The first capacitance is different from the second capacitance. The signal phase generator is coupled between the first port and the compensation circuit. The vector modulator is coupled between the compensation circuit and the second port.

Abstract: An apparatus is disclosed for bidirectional variable gain amplification. In an example aspect, an apparatus comprises an antenna element of an antenna array and a wireless transceiver. The wireless transceiver comprises a transmit path coupled to the antenna element, a receive path coupled to the antenna element, and a phase shifter disposed in both the transmit path and the receive path. The phase shifter is configured to operate in an active mode and comprises a first bidirectional variable gain amplifier and a second bidirectional variable gain amplifier.

Abstract: In certain aspects, a receiver includes first amplifiers, wherein each one of the first amplifiers comprises an input and an output. The receiver also includes second amplifiers, wherein each one of the second amplifiers comprises an input and an output, and the outputs of the second amplifiers are coupled to a combining node. The receiver also includes transmission lines, wherein each one of the transmission lines is coupled between the output of a respective one of the first amplifiers and the input of a respective one of the second amplifiers. The receiver further includes a load coupled to the combining node, and receiver elements, wherein each one of the receiver elements comprises an input and an output, and the output of each one of the receiver elements is coupled to the input of a respective one of the first amplifiers.

Abstract: An apparatus is disclosed for phase-shifting signals with a compensation circuit. In example implementations, an apparatus for phase-shifting signals includes a phase shifter having a first port and a second port. The phase shifter also includes a signal phase generator, a compensation circuit, and a vector modulator. The compensation circuit includes a first capacitor with a first capacitance and a second capacitor with a second capacitance. The first capacitance is different from the second capacitance. The signal phase generator is coupled between the first port and the compensation circuit. The vector modulator is coupled between the compensation circuit and the second port.

Abstract: An apparatus is disclosed for phase-shifting signals. In example implementations, the apparatus includes a phase shifter. The phase shifter includes a first port, a second port, a vector modulator coupled to the first port, and a signal phase generator. The signal phase generator includes multiple amplifiers coupled between the vector modulator and the second port. The signal phase generator also includes multiple capacitors that couple the multiple amplifiers together to form a loop. Each respective capacitor of the multiple capacitors is coupled between a respective pair of consecutive amplifiers of the multiple amplifiers to form the loop.