Abstract: Certain aspects of the present disclosure provide multi-way diversity receivers with multiple synthesizers. Such a multi-way diversity receiver may be implemented in a carrier aggregation (CA) transceiver. One example wireless reception diversity circuit generally includes three or more receive paths for processing received signals and two or more frequency synthesizing circuits configured to generate local oscillating signals to downconvert the received signals. Each of the frequency synthesizing circuits is shared by at most two of the receive paths, and each pair of the frequency synthesizing circuits may generate a pair of local oscillating signals having the same frequency.

Abstract: A phase locked loop has a frequency divider included in a feedback path. The frequency divider generates a first output and a delayed output. The phase locked loop also includes a charge pump to generate an output current based on the first output and the delayed output of the frequency divider.

Abstract: Certain aspects of the present disclosure generally relate to methods and apparatus for generating oscillating signals. For example, certain aspects of the present disclosure provide a phase-locked loop (PLL) having a first switch coupled to a sampling input node of the PLL, an integrator coupled to an output of the sampling circuit, and a voltage-controlled oscillator (VCO) having an input coupled to an output of the integrator. In certain aspects, the PLL may also include a feedback path coupled to an output of the VCO and a control input of the first switch.

Abstract: A phase locked loop has a frequency divider included in a feedback path. The frequency divider generates a first output and a delayed output. The phase locked loop also includes a charge pump to generate an output current based on the first output and the delayed output of the frequency divider.

Abstract: An apparatus includes a low noise amplifier (LNA) multiplexer configured to receive a plurality of radio frequency (RF) signals at a plurality of input terminals and to combine the plurality of RF signals into a combined RF signal that is output at an output terminal. The LNA multiplexer includes a plurality of input signal paths, and each input signal path is coupleable to a respective input terminal of the plurality of input terminals and is configured to receive a respective RF signal of the plurality of RF signals. The apparatus further includes an LNA demultiplexer configured to receive the combined RF signal at an input port coupled to the output terminal and to distribute the combined RF signal to a plurality of output ports, each output port of the plurality of output ports configured to output the combined RF signal to a respective downconverter of a plurality of downconverters.

Abstract: A dual-band voltage controlled oscillator (VCO) includes: a first oscillator circuit including a first inductor; a second oscillator circuit including a second inductor; a first mode switch configured to electrically connect or disconnect a first output terminal of the first oscillator circuit and a first output terminal of the second oscillator circuit; a second mode switch configured to electrically connect or disconnect a second output terminal of the first oscillator circuit and a second output terminal of the second oscillator circuit; a third mode switch configured to electrically connect or disconnect a first terminal of the first inductor and a first terminal of the second inductor; and a fourth mode switch configured to electrically connect or disconnect a second terminal of the first inductor and a second terminal of the second inductor.

Abstract: Certain aspects of the present disclosure provide multi-way diversity receivers with multiple synthesizers. Such a multi-way diversity receiver may be implemented in a carrier aggregation (CA) transceiver. One example wireless reception diversity circuit generally includes three or more receive paths for processing received signals and two or more frequency synthesizing circuits configured to generate local oscillating signals to downconvert the received signals. Each of the frequency synthesizing circuits is shared by at most two of the receive paths, and each pair of the frequency synthesizing circuits may generate a pair of local oscillating signals having the same frequency.

Abstract: Multiplex modules for use in carrier aggregation receivers are disclosed. In an exemplary embodiment, an apparatus includes an LNA multiplexer configured to receive a plurality of RF signals at a plurality of input terminals and to combine the RF signals into a combined RF signal that is output from an output terminal. The apparatus also includes an LNA demultiplexer configured to receive the combined RF signal at an input port that is connected to the output terminal and to distribute the combined RF signal to a plurality of output ports.

Abstract: Certain aspects of the present disclosure provide multi-way diversity receivers with multiple synthesizers. Such a multi-way diversity receiver may be implemented in a carrier aggregation (CA) transceiver. One example wireless reception diversity circuit generally includes three or more receive paths for processing received signals and two or more frequency synthesizing circuits configured to generate local oscillating signals to downconvert the received signals. Each of the frequency synthesizing circuits is shared by at most two of the receive paths, and each pair of the frequency synthesizing circuits may generate a pair of local oscillating signals having the same frequency.

Abstract: Certain aspects of the present disclosure provide methods and apparatus for dynamically adjusting a voltage-controlled oscillator (VCO) frequency, a local oscillator (LO) divider ratio, and/or a receive path when adding or discontinuing reception of a component carrier (CC) in a carrier aggregation (CA) scheme. This dynamic adjustment is utilized to avoid (or at least reduce) VCO, LO, and transmit signal coupling issues with multiple component carriers, with minimal (or at least reduced) current consumption by the VCO and the LO divider.

Abstract: A method includes generating a first signal based on a difference between a first frequency of a first voltage controlled oscillator (VCO) and a second frequency of a second VCO. The method further includes determining a gain of the first VCO at least partially based on the first signal.

Abstract: Methods and apparatus including: setting up a plurality of configurations for a plurality of local oscillator (LO) paths of a carrier aggregation (CA) transceiver operating with a plurality of bands; calculating and comparing frequencies for each LO path of the plurality of LO paths and at least one divider ratio of LO dividers for each band of the plurality of bands to identify frequency conflicts; and reconfiguring the LO dividers for the plurality of LO paths and the plurality of bands when the frequency conflicts are identified.

Abstract: A dual-band voltage controlled oscillator (VCO) includes: a first oscillator circuit including a first inductor; a second oscillator circuit including a second inductor; a first mode switch configured to electrically connect or disconnect a first output terminal of the first oscillator circuit and a first output terminal of the second oscillator circuit; a second mode switch configured to electrically connect or disconnect a second output terminal of the first oscillator circuit and a second output terminal of the second oscillator circuit; a third mode switch configured to electrically connect or disconnect a first terminal of the first inductor and a first terminal of the second inductor; and a fourth mode switch configured to electrically connect or disconnect a second terminal of the first inductor and a second terminal of the second inductor.

Abstract: Reconfiguring a transceiver design using a plurality of frequency synthesizers and a plurality of carrier aggregation (CA) receiver (Rx) and transmitter (Tx) chains, the method including: connecting a first frequency synthesizer to a first CA Tx chain; connecting the plurality of frequency synthesizers to the plurality of CA Rx chains, wherein a second frequency synthesizer of the plurality of frequency synthesizers is connected as a shared synthesizer to a first CA Rx chain and a second CA Tx chain.

Abstract: Certain aspects of the present disclosure provide techniques and apparatus for glitch-free bandwidth switching in a phase-locked loop (PLL). One example PLL generally includes a voltage-controlled oscillator (VCO) comprising a first variable capacitive element and a second variable capacitive element and a bandwidth adjustment circuit comprising a first switch in parallel with a resistor of a resistor-capacitor (RC) network. The bandwidth adjustment circuit is configured to open the first switch for a first bandwidth mode, close the first switch in a transition from the first bandwidth mode to a second bandwidth mode, and control a capacitance of the second variable capacitive element based on a voltage of a node of the RC network.

Abstract: A radio frequency (RF) front end having multiple low noise amplifiers modules is disclosed. In an exemplary embodiment, an apparatus includes at least one first stage amplifier configured to amplify received carrier signals to generate at least one first stage carrier group. Each first stage carrier group includes a respective portion of the carrier signals. The apparatus also includes second stage amplifiers configured to amplify the first stage carrier groups. Each second stage amplifier configured to amplify a respective first stage carrier group to generate two second stage output signals that may be output to different demodulation stages where each demodulation stage demodulates a selected carrier signal.

Abstract: Aspects of a wireless apparatus for configuring a plurality of VCOs are provided. The apparatus may be a UE. The UE receives a configuration for a plurality of carriers. Each carrier corresponds to a different LO frequency. In addition, the UE determines a VCO frequency for generating each LO frequency. Further, the UE assigns each determined VCO frequency to each of a plurality of VCO modules based on a distance between the VCO modules and each of the determined VCO frequencies. The plurality of VCO modules are of a set of VCO modules including at least three VCO modules.

Abstract: A device includes a main two-stage low noise amplifier (LNA) configured to amplify a carrier aggregation (CA) communication signal, the main two-stage LNA comprising a first LNA stage and a second LNA stage, an output of the first LNA stage having a first stage second order intermodulation product, the second LNA stage comprising a phase-inverter configured to phase-invert the output of the first LNA stage to generate a second stage phase-inverted output, and an auxiliary LNA stage coupled to the main two-stage LNA, the auxiliary LNA stage configured to cancel the first stage second order intermodulation product.

Abstract: A device includes a load circuit configured to receive an amplified communication signal, the load circuit having a center tapped inductor structure configured to divide the amplified communication signal into a first portion and a second portion, the load circuit configured to resonate at a harmonic of the amplified communication signal.

Abstract: An apparatus for generating an oscillating output signal includes an inductive-capacitive (LC) circuit and a current tuning circuit. The LC circuit includes a primary inductor and a varactor coupled to the primary inductor. A capacitance of the varactor is responsive to a voltage at a control input of the varactor. The current tuning circuit includes a secondary inductor and a current driving circuit coupled to the secondary inductor. The current driving circuit is responsive to a current at a control input of the current driving circuit. An effective inductance of the primary inductor is adjustable via magnetic coupling to the secondary inductor, and a frequency of the oscillating output signal is responsive to the effective inductance of the primary inductor and to the capacitance of the varactor.