Abstract: A direct power amplifier modulator that accepts bipolar I and Q data, either baseband or multi-carrier digital IF, and generates the resultant magnitude and sign components. Also described is a direct power amplifier modulator that generates quadrature terms of the carrier frequency offset by 90°, wherein each term is shifted by 180° under control of the respective sign components of the quadrature I and Q samples. The present invention also provides a transistor structure configured to accept differential quadrature frequency components that are combined in a post PA outphasing combiner.

Abstract: The present disclosure relates generally to systems and methods for combining stepped drain bias control with digital predistortion for a power amplifier. In one example, the method includes receiving an input associated with a transmit power level of a transmitter in a wireless terminal and selecting a predefined drain bias setting for a power amplifier of the wireless terminal based on the input. A predefined predistortion setting for the power amplifier corresponding to the selected predefined drain bias setting is identified. A drain of the power amplifier is set to the selected predefined drain bias setting, and the identified predefined predistortion setting is applied to a signal prior to directing the signal to the power amplifier.

Abstract: A lockable MEMS switching architecture provided having a clutch assembly, a switching member, and an actuator. The clutch assembly has one or more engagement features located in proximity to the switching member—particularly one or more receiving features located upon the switching member. The clutch assembly is actuated to disengage the engagement features from the receiving features. The switching member is actuated to move in relation to the clutch assembly. Once the switching member is in a desired position, the clutch assembly is de-actuated, causing the engagement features to re-engage with the switching member, thereby restricting its further movement.

Abstract: An architecture for a receiver component in a wireless communications system is disclosed—one that supports both zero intermediate frequency (ZIF) and near-zero intermediate frequency (NZIF) operation. The architecture provides a down-conversion segment, and a local oscillator segment operatively associated with the down-conversion segment. An analog-to-digital conversion (ADC) segment is adapted to receive signals from the down-conversion segment and introduce the signals into a digital intermediate frequency (DIF) construct. The DIF construct performs a DC offset compensation or DC residue filtering on NZIF-based signals, and droop or mismatch compensation. Image removal is performed on NZIF-based signals, and DC offset compensation is performed on ZIF-based signals. Compensated signals are amplified to some nominal or desired level, and interpolation filtering of the amplified signals is performed prior to transmission thereof.

Abstract: An architecture for a receiver component in a wireless communications system is disclosed—one that supports both zero intermediate frequency (ZIF) and near-zero intermediate frequency (NZIF) operation. The architecture provides a down-conversion segment, and a local oscillator segment operatively associated with the down-conversion segment. An analog-to-digital conversion (ADC) segment is adapted to receive signals from the down-conversion segment and introduce the signals into a digital intermediate frequency (DIF) construct. The DIF construct performs a DC offset compensation or DC residue filtering on NZIF-based signals, and droop or mismatch compensation. Image removal is performed on NZIF-based signals, and DC offset compensation is performed on ZIF-based signals. Compensated signals are amplified to some nominal or desired level, and interpolation filtering of the amplified signals is performed prior to transmission thereof.

Abstract: A multi-mode, multi-band mobile station for use in wireless networks operating under different air interface standards. The present invention, the mobile station comprises a plurality of low-noise amplifiers. Each of the plurality of low-noise amplifiers is optimized for use in a selected frequency band. The mobile station also comprises a near-zero intermediate frequency (NZIF) broadband image rejection mixer for receiving an amplified RF signal from a selected one of the plurality of low-noise amplifiers and down-converting the amplified RF signal to produce a first analog intermediate frequency (IF) signal.

Abstract: The present disclosure relates generally to systems and methods for optimized receiver performance in a low intermediate frequency (IF) architecture for EDGE (Enhanced Data rates for GSM Evolution). In one example, a method includes mixing a received analog signal with a local oscillator signal to create a mixed signal having an intermediate frequency between 101 kHz and 199 kHz. The mixed signal is compensated to minimize a direct current (DC) component introduced into the mixed signal by the local oscillator signal and an interferer image portion of the mixed signal is rejected. DC introduced into the mixed signal is minimized before final downconverting of the mixed signal, and DC remaining at the intermediate frequency after downconverting the mixed signal is minimized.

Abstract: A receiver system design and architecture that implements a 3-step gain LNA and an analog VGA for a WCDMA handsets and local area base stations, providing a wireless device eliminating the use of external bandpass filter between low-noise amplifier and first mixer.

Abstract: The present disclosure relates generally to systems and methods for combining stepped drain bias control with digital predistortion for a power amplifier. In one example, the method includes receiving an input associated with a transmit power level of a transmitter in a wireless terminal and selecting a predefined drain bias setting for a power amplifier of the wireless terminal based on the input. A predefined predistortion setting for the power amplifier corresponding to the selected predefined drain bias setting is identified. A drain of the power amplifier is set to the selected predefined drain bias setting, and the identified predefined predistortion setting is applied to a signal prior to directing the signal to the power amplifier.

Abstract: A Class S RF power amplifier for use in a radio frequency (RF) transmitter. The Class S power amplifier comprises a delta-sigma modulator that receives an analog modulated RF carrier and generates a pulse-width modulated binary signal. The Class S power amplifier also comprises a switch mode power amplifier that receives the pulse-width modulated binary signal generated by the delta-sigma modulator and generates an output carrier signal that switches between a fully on state and a fully off state. The sampling rate of the delta-sigma modulator is less than four times the frequency of the output carrier signal generated by the switch mode power amplifier.

Abstract: The present disclosure relates generally to systems and methods for direct current (DC) correction in wireless devices. In one example, a method includes setting a cutoff frequency of a filter at a first frequency, where a signal entering the filter is attenuated based on the cutoff frequency. If a qualified change is detected in a DC component of the signal, the cutoff frequency is set at a second frequency that attenuates more of the signal than the first frequency for a defined time period. The cutoff frequency may then be set to the first frequency after the defined time period.

Abstract: A multi-mode mobile station comprising 1) reconfigurable transceiver circuitry for communicating with wireless networks operating under different air interface standards; 2) a memory for storing at least a download configuration file and a home configuration file; and 3) a main controller for configuring the reconfigurable transceiver circuitry to operate according to a home network wireless standard using home configuration data retrieved from the home configuration file. If the main controller determines that a network operating according to the home network wireless standard cannot be found, the main controller is further capable of configuring the reconfigurable transceiver circuitry to operate according to a download channel wireless standard using download configuration data retrieved from the download configuration file.

Abstract: A system and method for minimizing a DC component of a received signal are disclosed. As one example, a system for minimizing a DC component of a signal in a wireless receiver is disclosed, which includes a programmable filter operable to filter the signal with at least one of a low cutoff frequency and a high cutoff frequency, and a transition unit coupled to the programmable filter, the transition unit operable to transition the programmable filter between the high cutoff frequency and the low cutoff frequency.

Abstract: The present disclosure relates generally to systems and methods for direct current (DC) correction in wireless devices. In one example, a method includes setting a cutoff frequency of a filter at a first frequency, where a signal entering the filter is attenuated based on the cutoff frequency. If a qualified change is detected in a DC component of the signal, the cutoff frequency is set at a second frequency that attenuates more of the signal than the first frequency for a defined time period. The cutoff frequency may then be set to the first frequency after the defined time period.

Abstract: An RF transmitter having an RF power amplifier comprising: 1) a drive transistor that receives an input RF signal and generates an output RF signal; and 2) a drain bias adaptation circuit for supplying drain current to the drive transistor. The drain bias adaptation circuit comprises: i) a first switch for coupling the drive transistor drain to a system supply voltage; ii) a second switch for coupling the drive transistor drain to a high supply voltage that is greater than the system supply voltage; iii) a first bypass capacitor coupled to the first switch for reducing noise in the drain current when the first switch is closed and the second switch is open; and iv) a second bypass capacitor coupled to the second switch for reducing noise in the drain current when the second switch is closed and the first switch is open.

Abstract: A method for providing digital adaptive predistortion in a subscriber station is provided that includes applying predistortion, based on a set of predistortion characteristics, to a transmit signal to generate a predistorted signal. An amplifier input signal is generated based on the predistorted signal. The amplifier input signal is amplified to generate an amplified signal. The amplified signal is sampled to generate a sampled signal. The sampled signal is processed through a receive channel of the subscriber station to generate a processed signal. A determination is made regarding whether to adjust the set of predistortion characteristics based on the processed signal.

Abstract: A digital automatic gain control (AGC) circuit for use in a radio frequency (RF) receiver. The AGC circuit comprises: 1) a first shifter for receiving an in-phase signal as a first series of X-bit samples and left-shifting each X-bit sample by a number of bits determined by a coarse scaling factor; 2) a first limiter for receiving the D most significant bits of the output of the first shifter and outputting a subset of the D most significant bits of the first shifter output; 3) a first multiplier for multiplying the subset of the D most significant bits of the first shifter output by a fine scaling factor to produce a first M-bit product; and 4) a gain adjustment circuit for comparing a power signal derived from the first M-bit product to a maximum threshold value and generating the coarse scaling factor and the fine scaling factor.

Abstract: A local multipoint distribution service base station apparatus for sending and receiving communication signals to and from subscribers includes a base unit having at least one rack which is adapted to receive at least one subrack. At least one communication signal generating unit is also arranged and configured to be received by the subrack. In addition, a transmitting/receiving unit is operationally connected to the base unit for transmitting and/or receiving the communication signals to and from the subscribers.

Abstract: A digital automatic gain control (AGC) circuit for use in a radio frequency (RF) receiver. The AGC circuit comprises: 1) a first shifter for receiving an in-phase signal as a first series of X-bit samples and left-shifting each X-bit sample by a number of bits determined by a coarse scaling factor; 2) a first limiter for receiving the D most significant bits of the output of the first shifter and outputting a subset of the D most significant bits of the first shifter output; 3) a first multiplier for multiplying the subset of the D most significant bits of the first shifter output by a fine scaling factor to produce a first M-bit product; and 4) a gain adjustment circuit for comparing a power signal derived from the first M-bit product to a maximum threshold value and generating the coarse scaling factor and the fine scaling factor.

Abstract: A local multipoint distribution service base station apparatus for sending and receiving communication signals to and from subscribers includes a base unit having at least one rack which is adapted to receive at least one subrack. At least one communication signal generating unit is also arranged and configured to be received by the subrack. In addition, a transmitting/receiving unit is operationally connected to the base unit for transmitting and/or receiving the communication signals to and from the subscribers.