Abstract: A system, such as a transceiver, for controlling an adjustable power level includes first and second power detectors, a network of attenuators, a compensator, a comparator, and a controller. The first power detector measures the power of a signal. The network of attenuators receives the signal and generates an attenuated signal. The compensator receives the attenuated signal and generates a compensated signal. The second power detector measures the power of the compensated signal. The comparator receives the respective outputs from the first and second power detectors and generates a first error signal. The controller enables the fixed attenuation, correspondingly adjusts the variable attenuation, receives a second error signal, and provides a control signal to the network of attenuators to nullify an attenuation mismatch introduced between the fixed attenuation and the variable attenuation. A corresponding method for controlling an adjustable power level is also disclosed.

Abstract: A system for transmitting and receiving data is provided. The system includes a direct-conversion receiver that receives a signal modulated on a carrier frequency signal. The direct-conversion receiver includes one or more subharmonic local oscillator mixers. A local oscillator is connected to the direct conversion receiver, and generates a signal having a frequency equal to a subharmonic of the carrier frequency signal. A transmitter is connected to the local oscillator, which uses the local oscillator signal to transmit outgoing data.

Abstract: The present application discloses various implementations of a mobile device including a power amplifier (PA) having a driving stage coupled to an output stage. The driving stage is configured to be selectably powered by one of a first voltage supply and a second voltage supply. The output stage is configured to be powered by the second voltage supply. The mobile device further includes a voltage supply selection switch configured to selectably power the driving stage by the second voltage supply when an output power of the PA is less than or equal to a threshold power.

Abstract: The present application discloses various implementations of a mobile device including a power amplifier (PA) having a driving stage coupled to an output stage. The driving stage is configured to be selectably powered by one of a first voltage supply and a second voltage supply. The output stage is configured to be powered by the second voltage supply. The mobile device further includes a voltage supply selection switch configured to selectably power the driving stage by the second voltage supply when an output power of the PA is less than or equal to a threshold power.

Abstract: A controller enables the integration of a DC-DC converter in a mobile handset. The controller includes an input conditioner and an event sensor. The input conditioner uses a peak detector to track the output of a regulator and responds to available baseband input signals. The event sensor directs coupling between a voltage source and the DC-DC converter in response to a bypass event.

Abstract: Embodiments provide improved systems and methods of gain control and calibration for wireless transmitters. In particular, embodiments allow linear gain control over the entire transmitter gain control range, independent of temperature/process variations. Embodiments require very low power consumption compared to existing approaches. Embodiments may also be used for gain control calibration during production time, thereby substantially reducing production calibration time and cost.

Abstract: Systems and methods are provided for detecting forward power sent to an antenna and reflected power reflected back from the antenna. Embodiments of the present invention provide systems and methods for measuring forward and reflected power and controlling the amount of power supplied to the antenna responsive to these measurements. Embodiments of the present invention enable the power sent to the antenna to be dynamically altered when antenna impendence changes (e.g., when the antenna gets too close to another object).

Abstract: Embodiments provide improved systems and methods of gain control and calibration for wireless transmitters. In particular, embodiments allow linear gain control over the entire transmitter gain control range, independent of temperature/process variations. Embodiments require very low power consumption compared to existing approaches. Embodiments may also be used for gain control calibration during production time, thereby substantially reducing production calibration time and cost.

Abstract: Various embodiments of systems and methods for generating local oscillator (LO) signals for a harmonic rejection mixer are provided. One embodiment is a system for generating local oscillator (LO) signals for a harmonic rejection mixer. One such system comprises a local oscillator, a divide-by-N frequency divider, a divide-by-three frequency divider, and a harmonic rejection mixer. The local oscillator is configured to provide a reference frequency signal. The divide-by-N frequency divider is configured to divide the reference frequency signal by a value N and provide an output signal. The divide-by-three frequency divider is configured to receive the output signal of the divide-by-N frequency divider and divide the output signal into three phase-offset signals. The harmonic rejection mixer is configured to receive the three phase-offset signals and eliminate third frequency harmonics.

Abstract: A system for calibrating a closed power control loop includes an adder configured to inject a test signal into an adjustable element, a first peak detector configured to determine an amplitude of the injected test signal, a second peak detector configured to determine an amplitude of a return test signal, a comparator configured to determine the difference between the injected test signal and the return test signal, and a calibration engine configured to adjust the adjustable element so that the return test signal is offset from the injected test signal by a predetermined amount.

Abstract: Embodiments enable a multi-band transmitter with significantly reduced architecture area by allowing maximum reuse of transmitter stages across supported frequency bands and signal standards. Further, embodiments allow a monolithic transmitter implementation by providing an integration-friendly differential to single-ended conversion stage. According to embodiments, the differential to single-ended conversion stage is readily configurable according to the frequency band and signal standard of operation of the transmitter.

Abstract: Various embodiments of systems and methods for generating local oscillator (LO) signals for a harmonic rejection mixer are provided. One embodiment is a system for generating local oscillator (LO) signals for a harmonic rejection mixer. One such system comprises a local oscillator, a divide-by-N frequency divider, a divide-by-three frequency divider, and a harmonic rejection mixer. The local oscillator is configured to provide a reference frequency signal. The divide-by-N frequency divider is configured to divide the reference frequency signal by a value N and provide an output signal. The divide-by-three frequency divider is configured to receive the output signal of the divide-by-N frequency divider and divide the output signal into three phase-offset signals. The harmonic rejection mixer is configured to receive the three phase-offset signals and eliminate third frequency harmonics.

Abstract: A transmitter adjusts a transmitted power level by modifying a control input of a variable gain amplifier. A power amplifier control system includes an envelope extractor, an error extractor, and a feed-forward multiplier. The envelope extractor receives data signal inputs and computes the envelope of the combined signal. The error extractor generates an error signal as a function of the combined signal and the output power generated by the power amplifier. The feed-forward multiplier generates a modified error signal that is responsive to a function of the gain in a feedback path. A corresponding method for controlling a power level is also disclosed. In some embodiments, a transmit chain with a power control loop is used to adjust the transmit signal power applied at an input of a variable gain amplifier. A corresponding method for adjusting the transmit signal power level is also included.

Abstract: A system for calibrating a closed power control loop includes an adder configured to inject a test signal into an adjustable element, a first peak detector configured to determine an amplitude of the injected test signal, a second peak detector configured to determine an amplitude of a return test signal, a comparator configured to determine the difference between the injected test signal and the return test signal, and a calibration engine configured to adjust the adjustable element so that the return test signal is offset from the injected test signal by a predetermined amount.

Abstract: Various embodiments of systems and methods for generating local oscillator (LO) signals for a harmonic rejection mixer are provided. One embodiment is a system for generating local oscillator (LO) signals for a harmonic rejection mixer. One such system comprises a local oscillator, a divide-by-N frequency divider, a divide-by-three frequency divider, and a harmonic rejection mixer. The local oscillator is configured to provide a reference frequency signal. The divide-by-N frequency divider is configured to divide the reference frequency signal by a value N and provide an output signal. The divide-by-three frequency divider is configured to receive the output signal of the divide-by-N frequency divider and divide the output signal into three phase-offset signals. The harmonic rejection mixer is configured to receive the three phase-offset signals and eliminate third frequency harmonics.

Abstract: A controller enables the integration of a DC-DC converter in an amplitude modulation power control loop in a mobile handset. The controller includes an input conditioner and an event sensor. The input conditioner uses a peak detector to track the output of a regulator and responds to available baseband input signals. The event sensor controls a switch that connects the DC-DC converter to a battery in response to a bypass event. The controller bypasses the DC-DC-converter when a transmitter is not enabled. The DC-DC converter is enabled prior to a transmission burst. A target voltage is determined from a series of detected peak voltages from the output of the regulator. The controller commands the DC-DC converter to transition to the target voltage until the end of a transmission burst.

Abstract: According to one embodiment, a radio frequency (RF) transceiver includes a transmitter enabling efficient preamplification gain control. The RF transceiver comprises a receiver and a power amplifier (PA) for amplifying a transmit signal of the transmitter. The transmitter is configured to provide pre-PA gain control for preamplifying the transmit signal before amplification by the PA, wherein substantially all of the pre-PA gain control is provided when the transmit signal is at a transmit frequency of the transmitter. In one embodiment, the transmitter includes a PA driver comprising in combination: a transconductance amplifier, a current steering block, and an output transformer. Each of the transconductance amplifier, current steering block, and output transformer is configured to contribute a respective variable gain control to the pre-PA gain control provided by the PA driver.

Abstract: A system for calibrating a closed power control loop includes an adder configured to inject a test signal into an adjustable element, a first peak detector configured to determine an amplitude of the injected test signal, a second peak detector configured to determine an amplitude of a return test signal, a comparator configured to determine the difference between the injected test signal and the return test signal, and a calibration engine configured to adjust the adjustable element so that the return test signal is offset from the injected test signal by a predetermined amount.

Abstract: Embodiments provide improved systems and methods of gain control and calibration for wireless transmitters. In particular, embodiments allow linear gain control over the entire transmitter gain control range, independent of temperature/process variations. Embodiments require very low power consumption compared to existing approaches. Embodiments may also be used for gain control calibration during production time, thereby substantially reducing production calibration time and cost.

Abstract: A controller enables the integration of a DC-DC converter in an amplitude modulation power control loop in a mobile handset. The controller includes an input conditioner and an event sensor. The input conditioner uses a peak detector to track the output of a regulator and responds to available baseband input signals. The event sensor controls a switch that connects the DC-DC converter to a battery in response to a bypass event. The controller bypasses the DC-DC-converter when a transmitter is not enabled. The DC-DC converter is enabled prior to a transmission burst. A target voltage is determined from a series of detected peak voltages from the output of the regulator. The controller commands the DC-DC converter to transition to the target voltage until the end of a transmission burst.