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: An apparatus includes a phase detector coupled to an output of a frequency multiplier. A digital loop filter is coupled to the phase detector, and a duty cycle correction circuit is coupled to the digital loop filter.

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: 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: An apparatus comprising a transmit path, a plurality of local oscillators and a control unit. The control unit may be configured to: receive an upcoming resource block (RB) allocation; determine whether the upcoming RB allocation is the same as the current RB allocation; in response to determining that the upcoming RB allocation is different than the current RB allocation: select an unused LO of the plurality of LOs; determine whether a number of allocated RBs associated with the upcoming RB allocation is greater than a threshold; and in response to determining that the number of allocated RBs associated with the upcoming RB allocation is not greater than the threshold, tune the selected LO to a frequency corresponding to the upcoming RB allocation.

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: An amplifier module with an output coupler is disclosed. The amplifier module may include a plurality of input terminals and two or more output terminals. Each input terminal may be coupled to an input of an independent amplifier. Outputs from the independent amplifiers may be coupled to the two or more output terminals. The amplifier module may include an output coupler to couple the two or more output terminals together. A signal may be received by a first output terminal and be coupled by the output coupler to a second output terminal. In some embodiments, when the two or more output terminals are coupled together, the independent amplifiers may be made inactive or operated in a minimum gain configuration.

Abstract: An amplifier module with an output coupler is disclosed. The amplifier module may include a plurality of input terminals and two or more output terminals. Each input terminal may be coupled to an input of an independent amplifier. Outputs from the independent amplifiers may be coupled to the two or more output terminals. The amplifier module may include an output coupler to couple the two or more output terminals together. A signal may be received by a first output terminal and be coupled by the output coupler to a second output terminal. In some embodiments, when the two or more output terminals are coupled together, the independent amplifiers may be made inactive or operated in a minimum gain configuration.

Abstract: An apparatus including: a current source configured to generate current; a bias node coupled to the current source; a switching current source circuit coupled to the current source and the bias node to allow the current to flow through the switching current source circuit into the bias node; a biasing circuit configured to receive a control signal from a phase detector, and mirror the current flowing through the switching current source circuit in response to the control signal; and a switch device disposed between the switching current source circuit and the biasing circuit to isolate the switching current source circuit from the biasing circuit.

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: An apparatus including: a current source configured to generate current; a switching current source circuit coupled to the current source and a first bias node to allow the current to flow through the switching current source circuit into the first bias node; a first bias circuit configured to receive a first control signal from a phase detector, the first bias circuit configured to mirror the current flowing through the switching current source circuit in response to the first control signal; a second bias circuit coupled to the first bias circuit at an output node and a second bias node, the second bias circuit configured to receive a second control signal from the phase detector; and a transconductance amplifier configured to receive a feedback signal from the output node and generate an output current to control the second biasing node.

Abstract: An apparatus including: a current source configured to generate current; a switching current source circuit coupled to the current source and a first bias node to allow the current to flow through the switching current source circuit into the first bias node; a first bias circuit configured to receive a first control signal from a phase detector, the first bias circuit configured to mirror the current flowing through the switching current source circuit in response to the first control signal; a second bias circuit coupled to the first bias circuit at an output node and a second bias node, the second bias circuit configured to receive a second control signal from the phase detector; and a transconductance amplifier configured to receive a feedback signal from the output node and generate an output current to control the second biasing node.

Abstract: An apparatus including: a current source configured to generate current; a bias node coupled to the current source; a switching current source circuit coupled to the current source and the bias node to allow the current to flow through the switching current source circuit into the bias node; a biasing circuit configured to receive a control signal from a phase detector, and mirror the current flowing through the switching current source circuit in response to the control signal; and a switch device disposed between the switching current source circuit and the biasing circuit to isolate the switching current source circuit from the biasing circuit.

Abstract: An apparatus including: a current source configured to generate current; a switching current source circuit coupled to the current source and a first bias node to allow the current to flow through the switching current source circuit into the first bias node; a first bias circuit configured to receive a first control signal from a phase detector, the first bias circuit configured to mirror the current flowing through the switching current source circuit in response to the first control signal; a second bias circuit coupled to the first bias circuit at an output node and a second bias node, the second bias circuit configured to receive a second control signal from the phase detector; and a transconductance amplifier configured to receive a feedback signal from the output node and generate an output current to control the second biasing node.

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: Techniques for detecting and correcting phase discontinuity of a local oscillator (LO) signal are disclosed. In one design, a wireless device includes an LO generator and a phase detector. The LO generator generates an LO signal used for frequency conversion and is periodically powered on and off. The phase detector detects the phase of the LO signal when the LO generator is powered on. The detected phase of the LO signal is used to identify phase discontinuity of the LO signal. The wireless device may further include (i) a single-tone generator that generates a single-tone signal used to detect the phase of the LO signal, (ii) a downconverter that downconverts the single-tone signal with the LO signal and provides a downconverted signal used by the phase detector to detect the phase of LO signal, and (iii) phase corrector that corrects phase discontinuity of the LO signal in the analog domain or digital domain.

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.