Marvellworld Trade Ltd.

Marvell International Limited

Alexander Zaslavsky

Brian Taylor Brunn

Gregory Takeo Uehara

Rony Ashkenazi

David Lipshitz

Nader Damavandi

David Ben-Eli

John E Vasa

Qiang Li

Ilan Meltser

Anish Cherian

A method for performing self-calibration and compensation of a detector offset is provided. The method includes: detecting for a calibration flag; if the calibration flag is detected, transmitting a first signal; reading and accumulating detector codes in response to the first signal; and calculating a detector offset based on the detector codes.

Self-calibration and compensation of detector offset in GSM transceivers power control loop

Aspects of the disclosure provide a circuit that includes an envelope processing circuitry and a voltage modulator. The envelope processing circuitry is configured to receive a stream of envelope values of a signal for transmission and output a supply modulation signal in response to the stream of envelope values based on an average-power-tracking (APT) calibration. The voltage modulator is configured to modulate a supply voltage to an amplifier according to the supply modulation signal. The amplifier operates under the supply voltage to amplify the signal for transmission.

Method and apparatus for envelope tracking calibration

A method includes holding in a memory of a receiver, for each temperature in a range of temperatures, a respective first parameter indicative of a frequency error of a crystal oscillator in the receiver at the temperature, and a respective second parameter indicative of an uncertainty of the first parameter. An operating temperature of the crystal oscillator is measured. One or more frequencies, for initial acquisition of signals from a transmitter, are selected based on the first and second parameters corresponding to the measured operating temperature. The receiver is tuned to receive the signals from the transmitter on at least one of the selected frequencies.

Initial acquisition using crystal oscillator

A method for controlling output signal power in a communication terminal includes accepting, from first and second measurement points along a transmission chain in a transmitter of the terminal, respective first and second signal representations of a communication signal to be transmitted by the communication terminal. A cross-correlation is computed between the first and second signal representations accepted from the first and second measurement points. An actual gain between the first and second measurement points is computed using the cross-correlation. An output power of the communication signal is adjusted by setting a gain of the transmitter responsively to the actual gain.

Power control using fast signal time alignment

A wireless communications system includes a clock module, a global positioning system (GPS) module, an integrated circuit for a cellular transceiver, and a baseband module. The clock module is configured to generate a first clock reference that is not corrected using automatic frequency correction (AFC). The GPS module is configured to operate in response to the first clock reference. The integrated circuit includes a system phase lock loop (PLL) configured to (i) operate in response to the first clock reference, and (ii) generate a corrected clock reference by performing AFC on the first clock reference in response to an AFC signal. The baseband module is configured to (i) operate in response to the first clock reference from the clock module, and (ii) generate the AFC signal.

Wireless communications system including dual-purpose clock reference for global positioning system and baseband

A circuit includes a transmit path to receive an input signal and generate an output signal to be output at a transmit power level according to a power target signal. The circuit also includes a gain corrector to output a signal for adjusting a power level of the output signal to correspond to the transmit power level. The signal for adjusting is based on the power target signal and a delay for time-aligning a first signal and a second signal.

Method for fast automatic power control of wireless transmitters

A wireless communications system includes a clock module, a communications module, a receiver module, and a baseband module. The clock module is configured to generate a first clock reference. The communications module is configured to operate in response to the first clock reference and independent of a corrected clock reference. The corrected clock reference is generated by performing automatic frequency correction on the first clock reference according to an automatic frequency correction signal. The receiver module is configured to (i) receive radio frequency signals from a wireless medium, and (ii) in response to the corrected clock reference, generate baseband signals based on the received radio frequency signals. The baseband module is configured to (i) receive the baseband signals, and (ii) in response to a selected one of the first clock reference and the corrected clock reference, generate the automatic frequency correction signal based on the baseband signals.

Clock multiplexing for baseband automatic frequency correction

A method for DC offset cancellation includes defining, in a range of possible gain values for operating a direct conversion receiver, multiple sub-ranges of the possible gain values. Multiple DC offset correction values for the respective sub-ranges are stored in a memory. Upon detecting at the receiver that a gain of the receiver has changed from a first sub-range to a second sub-range, DC offset cancellation is initiated based on a DC offset correction value stored for the second sub-range and on a condition relating to past operation in the second sub-range.

DC offset cancellation in direct conversion receivers

A system includes a first clock module, a global positioning system (GPS) module, a phase-locked loop (PLL) module, a cellular transceiver, and a baseband module. The first clock module generates a first clock reference. The GPS module operates in response to the first clock reference. The WLAN module operates in response to the first clock reference. The PLL module generates a second clock reference by performing automatic frequency correction (AFC) on the first clock reference in response to an AFC signal. The cellular transceiver receives radio frequency signals from a wireless medium and generates baseband signals in response to the received radio frequency signals. The baseband module receives the baseband signals, operates in response to a selected one of the first clock reference and the second clock reference, and generates the AFC signal in response to the baseband signals.

System and transceiver clocking to minimize required number of reference sources in multi-function cellular applications including GPS

A method includes receiving a signal using a direct conversion receiver, while the receiver is set at a gain that is selected from a range of possible gain values. Multiple DC offset correction values are provided for use by a DC offset cancellation loop, each DC offset correction value being associated with a respective sub-range of the range of the possible gain values. A DC offset correction value is selected from among the multiple DC offset correction values based on the gain to which the receiver is set. A DC offset in the signal is canceled by setting the DC offset cancellation loop to the selected DC offset correction value.

A transmitter includes a Power Amplifier (PA), an antenna, at least one passive component and control circuitry. The PA is controlled by a PA control voltage, is operative to amplify a Radio Frequency (RF) signal and has input and output amplifier terminals. The passive component has an input component terminal coupled to the output amplifier terminal of the PA and an output component terminal coupled to the antenna. The control circuitry is configured to determine an interim power level at the output amplifier terminal that causes the signal at the output component terminal to have a target output power level, to determine, based on the interim power level, a given PA control voltage that makes the interim power level producible by the PA, so that the signal at the output component terminal has the target output power level, and to apply the given PA control voltage to the PA.

Setting of power amplifier control voltage

A method in a transmitter including a transmission chain and a Power Amplifier (PA), includes storing calibration data relating a plurality of specified output power levels of the transmitter to respective PA control voltages for application to the PA and respective gain levels for application to the transmission chain that cause the transmitter to output signals at the specified output power levels. A target output power level is specified, and an actual control voltage is applied to the PA. The actual control voltage is derived from a specified target control voltage depending on the target output power. A modified gain level which, when applied to the transmission chain while the PA is controlled with the actual control voltage, causes the transmitter to output the signals at the target output power level, is computed based on the calibration data. The modified gain level is applied to the transmission chain.

High-accuracy transmit power control with high-efficiency operation amplifier operation

A method for power control, including determining a need in a transmitter to perform a first output power update and then a second output power update. The method includes selecting a control mode for the first output power update and a control mode for the second output power update prior to performing the first output power update. The control modes are selected from a closed loop mode and an open loop mode, and the selection is based on a function of a current output power, a power to be applied at the first output power update, and a power to be applied at the second output power update. The method includes performing the first output power update using the first control mode, and then performing the second output power update using the second control mode, without measuring a power level applied responsively to performing the first output power update.

Selection of closed-loop/open-loop power control in user equipment

A system comprises a first clock module configured to generate a first clock reference that is not corrected using automatic frequency correction (AFC). A global position system (GPS) module is configured to receive the first clock reference. An integrated circuit for a cellular transceiver includes a system phase lock loop configured to receive the first clock reference, to perform AFC, and to generate a second clock reference that is AFC corrected.

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Petach Tikva, Israel

Alexander Zaslavsky