Abstract: A technique of operating a wireless communication device includes receiving, at a first wireless communication device, respective signals transmitted from multiple second wireless communication devices. Respective channel matrix blocks for each block of the received respective signals are then generated. Finally, respective channel equalizer matrix blocks for each of the respective channel matrix blocks are generated. At least one of the respective channel equalizer matrix blocks is generated without performing a matrix inversion operation on an associated one of the respective channel matrix blocks.

Abstract: A method for efficiently calculating signal thresholds for use in signal processing is described. The method computes and stores a cumulative histogram and a weighted cumulative histogram. The method then provides a first estimate for a threshold based on a single ratio. The method next performs an iterative computation to get to the ultimate threshold result. Method iterations only require multiplication and addition operations on the stored values making the method well suited for implementation in fixed-point digital signal processors.

Abstract: A technique of operating a wireless communication device includes receiving, at a first wireless communication device, respective signals transmitted from multiple second wireless communication devices. Respective channel matrix blocks for each block of the received respective signals are then generated. Finally, respective channel equalizer matrix blocks for each of the respective channel matrix blocks are generated. At least one of the respective channel equalizer matrix blocks is generated without performing a matrix inversion operation on an associated one of the respective channel matrix blocks.

Abstract: A method for efficiently calculating signal thresholds for use in signal processing is described. The method computes and stores a cumulative histogram and a weighted cumulative histogram. The method then provides a first estimate for a threshold based on a single ratio. The method next performs an iterative computation to get to the ultimate threshold result. Method iterations only require multiplication and addition operations on the stored values making the method well suited for implementation in fixed-point digital signal processors.

Abstract: A method and apparatus for predistortion training in an amplifier using predistortion is provided herein. Predistortion takes place by collecting a series of envelope errors and averaging the envelope errors for various amplitude regions. LUT values are modified based on a curve-fit to the average amplitude values for each amplitude region. By utilizing a curve-fitting technique, the pitfalls of modifying individual LUT coefficients is avoided. Particularly, because the errors are collected in relatively broad regions and then averaged, the importance of exact correlation between a measured error and a specific LUT entry is significantly lessened.

Abstract: A method of channel estimation in a Code Division Multiple Access (CDMA) transmission system that incorporates Pilot Symbol Assisted Modulation (PSAM) using an iterative coherent detection method to estimate the phase and frequency of the received pilot symbols. Arctangent calculations are used to estimate phase and frequency. An iterative least squares linearization identifies and corrects values of the arctangent associated with an incorrect 2? alias, which arise due to the multiple-valued nature of the arctangent function. An alternative non-iterative least squares linearization also corrects the arctangent values, based on a calculation involving stored values of the pilot symbols.

Abstract: A method for linearizing an amplifier to produce an amplified output signal from a set of carrier frequencies is disclosed in which a set of digital baseband signals corresponding to the set of carrier frequencies are combined to produce an extended digital baseband signal. Look-up values are then derived from the power values of the extended digital baseband signal and applied to a look-up table to obtain predistortion values. One or more predistorted signals are then produced by complex mixing the predistortion values with one of the set of extended digital baseband signals. The predistorted signal(s) are then amplified to produced an output signal which is linearly related to the set of digital baseband signals.

Abstract: A method for predistorting a digital signal prior to amplification is disclosed in which a look-up table is computed using power values of digital input signal samples as look-up values. The look-up table is preferably a function of pre-measured calibration data. The look-up table is applied to digital input signals for producing the predistorted signal. Computing the look-up table may include determining a set of input power values, obtaining the pre-measured calibration data including an output power data value and phase data value of the amplifier corresponding to each of the input power values, and deriving a set of calibration power values using the output power data values. The calibration power values and the input power values are then used to derive amplitude predistortion calibration values while the phase data values are used to determine phase predistortion calibration values.