Abstract: A system and method for signal mismatch compensation in a wireless receiver is disclosed. The method includes receiving an in-phase (I) signal and a quadrature (Q) signal corresponding to the I signal, the Q signal having an ideal phase offset of 90 degrees from the I signal, where there is a phase and gain mismatch between the I signal and Q signal. The method adjusts the phase offset between the I signal and the Q signal to minimize the IQ power, where the IQ power is the average-time power of a digital baseband in-phase (DB-I) signal and a digital baseband quadrature (DB-Q) signal, corresponding to the I signal and Q signal, respectively. The method adjusts the gain of the Q signal to minimize the IQ power, whereby the phase and gain mismatch between the I signal and Q signal is minimized.

Abstract: A multi-mode digital down-converter for down-converting an incoming IF signal to baseband according to a selected air interface standard. The down-converter comprises a re-configurable gain control block controlled by a first gain parameter for amplifying the incoming IF signal and a mixer stage for down-converting the amplified incoming IF signal to produce a first in-phase baseband signal. The down-converter further comprises a reconfigurable CIC decimation filter block controlled by a second gain parameter and a first decimation parameter. The reconfigurable CIC decimation filter block filters the first in-phase baseband signal according to the second gain parameter and decimates the first in-phase baseband signal according to the first decimation parameter. The first and second gain parameters and the first decimation parameter are determined by the selected air interface standard.

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 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 signal mismatch compensation in a wireless receiver is disclosed. The method includes receiving an in-phase (I) signal and a quadrature (Q) signal corresponding to the I signal, the Q signal having an ideal phase offset of 90 degrees from the I signal, where there is a phase and gain mismatch between the I signal and Q signal. The method adjusts the phase offset between the I signal and the Q signal to minimize the IQ power, where the IQ power is the average-time power of a digital baseband in-phase (DB-I) signal and a digital baseband quadrature (DB-Q) signal, corresponding to the I signal and Q signal, respectively. The method adjusts the gain of the Q signal to minimize the IQ power, whereby the phase and gain mismatch between the I signal and Q signal is minimized.

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 digital in-phase/quadrature (I/Q) demodulator for use in RF receivers, wireless base stations, wireless mobile stations and other components of wireless networks. The digital I/Q demodulator extracts and resolves I and Q components of a demodulated digital data signal from a modulated digital data signal input thereto. The digital I/Q demodulator includes a self contained carrier signal recovery loop for constructing, from acquired phase information and a frequency input the digital I/Q demodulator from a first of plural programmable inputs thereto, a local carrier signal used in the demodulation process.

Abstract: A multi-mode digital down-converter for down-converting an incoming IF signal to baseband according to a selected air interface standard. The down-converter comprises a re-configurable gain control block controlled by a first gain parameter for amplifying the incoming IF signal and a mixer stage for down-converting the amplified incoming IF signal to produce a first in-phase baseband signal. The down-converter further comprises a reconfigurable CIC decimation filter block controlled by a second gain parameter and a first decimation parameter. The reconfigurable CIC decimation filter block filters the first in-phase baseband signal according to the second gain parameter and decimates the first in-phase baseband signal according to the first decimation parameter. The first and second gain parameters and the first decimation parameter are determined by the selected air interface standard.

Abstract: A multi-mode digital down-converter for down-converting an incoming IF signal to baseband according to a selected air interface standard. The down-converter comprises a re-configurable gain control block controlled by a first gain parameter for amplifying the incoming IF signal and a mixer stage for down-converting the amplified incoming IF signal to produce a first in-phase baseband signal. The down-converter further comprises a reconfigurable CIC decimation filter block controlled by a second gain parameter and a first decimation parameter. The reconfigurable CIC decimation filter block filters the first in-phase baseband signal according to the second gain parameter and decimates the first in-phase baseband signal according to the first decimation parameter. The first and second gain parameters and the first decimation parameter are determined by the selected air interface standard.

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 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.