Abstract: A wireless device for waveform scaling is disclosed. The wireless device includes a modulator that increases a magnitude of a peak digital code beyond a maximum available digital code for transmit power levels below a transmit power threshold to produce an adjusted digital code. The magnitude of the peak digital code is not increased beyond the maximum available digital code for transmit power levels above the transmit power threshold. The wireless device also includes a digital-to-analog converter that converts the adjusted digital code into an analog signal.

Abstract: A wireless device with power amplifiers having different characteristics to support transmission on multiple antennas is disclosed. These power amplifiers may have different gain, different maximum output power levels, etc. in order to meet requirements of different wireless systems. In an exemplary design, an apparatus includes first and second power amplifiers having different characteristics. The first power amplifier amplifies a first input signal and provides a first output signal for a first antenna. The second power amplifier amplifies the first input signal or a second input signal and provides a second output signal for a second antenna, e.g., in a MIMO mode or a transmit diversity mode. Only the first or second power amplifier amplifies another input signal and provides another output signal to the first antenna, e.g., in a CDMA mode or a GSM mode.

Abstract: A wireless device with power combining power amplifiers to support transmission on multiple antennas is disclosed. The power amplifiers may be operated together to obtain higher output power or separately to support transmission on multiple antennas. In an exemplary design, an apparatus includes first and second power amplifiers. The first power amplifier amplifies a first input signal and provides a first output signal for a first antenna in a first operating mode (e.g., a MIMO mode or a transmit diversity mode). The second power amplifier amplifies the first input signal or a second input signal and provides a second output signal for a second antenna in the first operating mode. The first and second power amplifiers are power combined in a second operating mode to provide a third output signal, which has a higher maximum output power than the first or second output signal.

Abstract: A system for precise calibration of electronic components is disclosed. In an exemplary embodiment, an apparatus for calibrating a tunable component on an integrated circuit chip includes an on-chip reference component configured to generate a first on-chip reference level, an on-chip connector configured to couple to an external test unit component to generate a second on-chip reference level, and an on-chip memory configured to store at least one error adjustment parameter determined from a difference between the first on-chip reference level and the second on-chip reference level, and wherein the at least one error adjustment parameter is configured to calibrate the tunable component to a desired value.

Abstract: A wireless device is described. The wireless device includes a high precision power/peak detector. The wireless device also includes a reference signal source. The high precision power/peak detector and the reference signal source are on an integrated circuit. The reference signal source provides a precision reference signal used to calibrate the high precision power/peak detector.

Abstract: In a first aspect, an RF switch includes a main transistor and a gate-to-source shorting circuit. When the RF switch is turned off, the gate-to-source shorting circuit is turned on to short the source and gate of the main transistor together, thereby preventing a Vgs from developing that would cause the main transistor to leak. When the RF switch is turned on, the gate-to-source shorting circuit is turned off to decouple the source from the gate. The gate is supplied with a digital logic high voltage to turn on the main transistor. In a second aspect, an RF switch includes a main transistor that has a bulk terminal. When the RF switch is turned off, the bulk is connected to ground through a high resistance. When the RF switch is turned on, the source and bulk are shorted together thereby reducing the threshold voltage of the main transistor.

Abstract: A baseband filter and upconverter with configurable efficiency for use in wireless transmitters is disclosed. In an exemplary embodiment, an apparatus is provided that includes a baseband filter having configurable efficiency, and an upconverter having configurable efficiency and coupled to the baseband filter. The baseband filter and upconverter are configured to operate at a first efficiency level in a first output power range and to operate at a second efficiency level in a second output power range.

Abstract: A high efficiency transmitter is disclosed. In an exemplary embodiment, a transmitter is provided that includes a first transmission path configured to receive a baseband signal and generate a first RF output when output power is in a first output power range, and a second transmission path configured to receive the baseband signal and generate a second RF output when the output power is in a second output power range.

Abstract: A wireless device with power combining power amplifiers to support transmission on multiple antennas is disclosed. The power amplifiers may be operated together to obtain higher output power or separately to support transmission on multiple antennas. In an exemplary design, an apparatus includes first and second power amplifiers. The first power amplifier amplifies a first input signal and provides a first output signal for a first antenna in a first operating mode (e.g., a MIMO mode or a transmit diversity mode). The second power amplifier amplifies the first input signal or a second input signal and provides a second output signal for a second antenna in the first operating mode. The first and second power amplifiers are power combined in a second operating mode to provide a third output signal, which has a higher maximum output power than the first or second output signal.

Abstract: A wireless device with power amplifiers having different characteristics to support transmission on multiple antennas is disclosed. These power amplifiers may have different gain, different maximum output power levels, etc. in order to meet requirements of different wireless systems. In an exemplary design, an apparatus includes first and second power amplifiers having different characteristics. The first power amplifier amplifies a first input signal and provides a first output signal for a first antenna. The second power amplifier amplifies the first input signal or a second input signal and provides a second output signal for a second antenna, e.g., in a MIMO mode or a transmit diversity mode. Only the first or second power amplifier amplifies another input signal and provides another output signal to the first antenna, e.g., in a CDMA mode or a GSM mode.

Abstract: A global navigation satellite system receiver with filter bypass mode for improved sensitivity is disclosed. In an aspect, an apparatus is provided that includes a non-bypass signal path coupled to a receiver, the non-bypass signal path comprising a filter. The apparatus also includes a bypass signal path coupled to the receiver, the bypass signal path configure to bypass the filter, and a switch to couple an antenna to the non-bypass signal path during time intervals when signals transmitted by an unrelated local transmitter are transmitted with a signal power that exceeds a selected threshold, and to couple the antenna to the bypass signal path during other time intervals.

Abstract: A wireless device for waveform scaling is disclosed. The wireless device includes a modulator that increases a magnitude of a peak digital code beyond a maximum available digital code for transmit power levels below a transmit power threshold to produce an adjusted digital code. The magnitude of the peak digital code is not increased beyond the maximum available digital code for transmit power levels above the transmit power threshold. The wireless device also includes a digital-to-analog converter that converts the adjusted digital code into an analog signal.

Abstract: Disclosed are circuits, techniques and methods for implementing an attenuator in a signal transmission path. In one particular implementation, an attenuation may be adjusted based, at least in part, on a control signal. In another implementation, such an attenuation may be adjusted in coarse increments by varying one or more gate voltages applied one or more transistors. In yet another implementation, adjusting said attenuation in fine increments by varying a bias voltage applied to at least one level shifter.

Abstract: In a first aspect, an RF switch includes a main transistor and a gate-to-source shorting circuit. When the RF switch is turned off, the gate-to-source shorting circuit is turned on to short the source and gate of the main transistor together, thereby preventing a Vgs from developing that would cause the main transistor to leak. When the RF switch is turned on, the gate-to-source shorting circuit is turned off to decouple the source from the gate. The gate is supplied with a digital logic high voltage to turn on the main transistor. In a second aspect, an RF switch includes a main transistor that has a bulk terminal. When the RF switch is turned off, the bulk is connected to ground through a high resistance. When the RF switch is turned on, the source and bulk are shorted together thereby reducing the threshold voltage of the main transistor.

Abstract: An upconverter and a downconverter having good performance are described. In one design, the upconverter includes first, second, and third sets of transistors. The first set of transistors receives baseband signals and provides an upconverted signal. The second set of transistors switches the transconductance of the transistors in the first set based on transmit (TX) local oscillator (LO) signals. The third set of transistors enables and disables the transistors in the second set based on a TX VCO signal. In one design, the downconverter includes first, second, and third sets of transistors. The first set of transistors receives a modulated signal and provides baseband signals. The second set of transistors switches the transconductance of the transistors in the first set based on receive (RX) LO signals. The third set of transistors enables and disables the transistors in the second set based on an RX VCO signal.

Abstract: A method for compensating for phase discontinuities on a communication device is described. A communication device may determine a desired output power. The communication device may determine a Digital-to-Analog Converter (DAC) gain corresponding to the desired output power. The communication device may determine a cumulative phase offset based on the DAC gain. The communication device may apply the DAC gain. The communication device may apply a phase compensation to a rotator to adjust for the cumulative phase offset.

Abstract: An upconverter and a downconverter having good performance are described. In one design, the upconverter includes first, second, and third sets of transistors. The first set of transistors receives baseband signals and provides an upconverted signal. The second set of transistors switches the transconductance of the transistors in the first set based on transmit (TX) local oscillator (LO) signals. The third set of transistors enables and disables the transistors in the second set based on a TX VCO signal. In one design, the downconverter includes first, second, and third sets of transistors. The first set of transistors receives a modulated signal and provides baseband signals. The second set of transistors switches the transconductance of the transistors in the first set based on receive (RX) LO signals. The third set of transistors enables and disables the transistors in the second set based on an RX VCO signal.