Patent application number | Description | Published |
20130058387 | WIRELESS COMMUNICATIONS DEVICE WITH PERFORMANCE MONITORING AND ASSOCIATED METHODS - A mobile wireless communications device includes a transceiver comprising a transmitter and a receiver, an auxiliary receiver, and a controller. The transmitter is configured to upconvert a transmit baseband modulated signal and generate an RF modulated signal having a transmit impairment. The auxiliary receiver is configured to downconvert the RF modulated signal and generate a receive baseband modulated signal having the transmit impairment. The auxiliary receiver is selectively configured to operate based on a control signal in a single-mixer mode when the transmitter is selectively configured to operate in a dual-mixer mode, and in the dual-mixer mode when the transmitter is selectively configured to operate in the single-mixer mode. The controller is configured to compare the transmit baseband modulated signal to the transmit impairment to determine an error difference therebetween, and generate the control signal based on the error difference. | 03-07-2013 |
20130058388 | WIRELESS COMMUNICATIONS DEVICE WITH IMPAIRMENT COMPENSATION AND ASSOCIATED METHODS - A mobile wireless communications device includes a transceiver, an auxiliary receiver and a controller. The transceiver includes a transmitter and a receiver. The transmitter upconverts a transmit baseband modulated signal and generates an RF modulated signal having a transmit impairment. The auxiliary receiver is coupled to the transmitter and downconverts the RF modulated signal and generates a receive baseband modulated signal having a receive impairment therein spectrally separated from the transmit impairment. The controller is coupled to the transmitter and the auxiliary receiver and estimates the transmit impairment while ignoring the receive impairment based on comparing the transmit baseband modulated signal with the receive baseband modulated signal. The controller generates an impairment compensation signal based upon the estimated transmit impairment. | 03-07-2013 |
20130082853 | DIGITAL TO ANALOG CONVERTER - A digital-to-analog converter is disclosed. The converter includes a gradient correction module that generates a correction term based on a model of gradient error. The correction term is then applied to the signal path in the digital domain or applied to the output of the digital-to-analog converter in the analog domain. The model used to generate the correction term is based on a vertical gradient error in the array of current source elements, which may be modelled and calibrated using a second-order polynomial. Further, a digital-to-analog converter having a Nyquist DAC and an oversampled DAC is disclosed. When the oversampled DAC is enabled, the resolution of the Nyquist DAC may be increased while slowing the conversion rate. | 04-04-2013 |
20130095777 | METHODS AND APPARATUS FOR POWER CONTROL - Various embodiments include a method for controlling power in a transmitter, the method comprising measuring an indication of an output power of the transmitter, comparing a first value corresponding to the indication of the output power to a second value corresponding to a desired output power; and adjusting a bias of at least one component in the transmitter in order to bring the output power closer to the desired output power. Embodiments also include various methods, systems and apparatus. | 04-18-2013 |
20130165056 | WIRELESS COMMUNICATIONS DEVICE WITH AN ADJUSTABLE IMPEDANCE MATCHING NETWORK AND ASSOCIATED METHODS - A mobile wireless communications device includes a portable housing, a transmitter carried by the portable housing and configured to modulate an input signal, and an adjustable impedance matching network coupled downstream from the transmitter. An antenna is coupled downstream from the adjustable impedance matching network, and a non-directional coupler is coupled between the adjustable impedance matching network and the antenna. A feedback receiver is coupled to the non-directional coupler to generate a feedback signal. A controller is configured to control the adjustable impedance matching network based upon the input signal and the feedback signal. | 06-27-2013 |
20130176011 | DCDC CONVERTER WITH CONVERTER MODULES THAT CAN BE DYNAMICALLY ENABLED OR DISABLED - Provided is an apparatus comprising a DCDC converter having a plurality of converter modules each configured to convert current from a first voltage level to another voltage form. In accordance with an embodiment of the disclosure, the converter modules are configured to be dynamically enabled or disabled such that only each converter module that has been enabled converts current for an output of the DCDC converter. Any inefficiency that would have been introduced by converter modules that are not needed are mitigated or eliminated altogether. The effect is that efficiency can be improved during low load conditions when there is no need to enable all of the converter modules. | 07-11-2013 |
20130195152 | MOBILE WIRELESS COMMUNICATIONS DEVICE HAVING AUXILIARY RECEIVER TO DETERMINE TRANSMIT IMPAIRMENT AND GENERATE TRANSMIT IMPAIRMENT COMPENSATION SIGNAL, AND ASSOCIATED METHODS - A communications device includes a baseband input to receive a baseband signal. A transmitter is coupled to the baseband input and generates a transmit signal based upon the baseband signal, the transmit signal having an initial transmit impairment. An auxiliary receiver is coupled to the transmitter and generates a receive signal having a receive impairment therein resulting from the initial transmit impairment. A controller determines a power of the baseband signal by integrating a product of the receive signal and a complex conjugate of the baseband signal, and determines a power of the receive signal by integrating a product of the baseband signal and the receive signal. The controller also determines the initial transmit impairment based upon the power of the baseband signal and the receive signal, and generates a transmit impairment compensation signal based upon the initial transmit impairment. | 08-01-2013 |
20130196716 | COMMUNICATIONS DEVICE AND METHOD HAVING NON-TOUCH BASED INPUT SCREEN - A communications device includes a housing and a wireless transceiver and processor carried by the housing and operative with each other. An input screen is carried by the housing and comprises a plurality of spaced transceivers positioned at the input screen and connected to the processor and each configured to transmit a millimeter wave RF signal and receive reflected signals from an object positioned close to the input screen. The processor is configured to determine the location of the object relative to the input screen based on the reflected signals received at each transceiver. | 08-01-2013 |
20130196719 | MOBILE WIRELESS COMMUNICATIONS DEVICE INCLUDING SENSING TRANSISTOR AND HYSTERETIC COMPARATOR AND RELATED METHODS - A mobile wireless communications device may include a portable housing, and a supply modulator carried by the portable housing. The supply modulator may include an output node, a linear amplifier coupled to the output node, and a switching amplifier also coupled to the output node. The switching amplifier may include at least one sensing transistor configured to sense current output from the linear amplifier and generate a drive voltage, and a hysteretic comparator coupled to the at least one sensing transistor and configured to be driven by the drive voltage. The mobile wireless communications device may also include a radio frequency (RF) power amplifier coupled to the output node of the supply modulator, and a wireless transceiver carried by the portable housing and coupled to the RF power amplifier. | 08-01-2013 |
20130208770 | COMMUNICATIONS DEVICE HAVING CONTROLLER TO CORRECT AN INITIAL IQ IMBALANCE AND ASSOCIATED METHODS - A communications device includes a plurality of wireless transmitters operable at different respective frequencies and each configured to generate respective IQ signals having an initial IQ imbalance. The communications device also includes a frequency tunable auxiliary receiver, and a controller. The controller is configured to selectively couple a given wireless transmitter to the frequency tunable auxiliary receiver and tune the frequency tunable auxiliary receiver to a frequency of the given wireless transceiver, and apply predistortion to the given wireless transmitter based upon the initial IQ imbalance to reduce the initial IQ imbalance. | 08-15-2013 |
20130208827 | METHOD AND APPARATUS TO USE AUXILIARY RECEIVER TO COMPENSATE MULTIPLE TRANSMITTERS BASED UPON ONE OF THE TRANSMITTERS - A communications device includes a plurality of wireless transmitters operable at different respective frequencies and each configured to generate respective IQ signals having an initial IQ imbalance. An auxiliary receiver is coupled to a given wireless transmitter. In addition, a controller is configured to apply predistortion to the each wireless transmitter of the plurality thereof based upon the initial IQ imbalance generated by the given wireless transmitter to reduce the initial IQ imbalance in each wireless transmitter. | 08-15-2013 |
20140118081 | Multiplexed Configurable Sigma Delta Modulators for Noise Shaping in a 25-Percent Duty Cycle Digital Transmitter - A modulator generates a baseband digital signal from an information-bearing digital signal. The baseband signal has time-varying phase and amplitude defined by a sequence of complex data words, each having an in-phase (I) component and a quadrature (Q) component. A noise-shaping modulator generates a noise-shaped digital signal from the baseband digital signal such that quantization noise in the noise-shaping modulator is attenuated by a spectral null of its noise transfer function. The spectral null is selected by a noise-shaping parameter corresponding to a selected one of a plurality of output frequencies. A signal converter generates an analog signal conveying the information of the information-bearing digital signal on an analog carrier signal having the selected output frequency. | 05-01-2014 |
20140126671 | DIGITAL QUADRATURE TRANSMITTER USING GENERALIZED COORDINATES - In one embodiment, a sequence of a plurality of pairs of in-phase (I) and quadrature (Q) modulated signal samples are applied to a radio frequency digital-to-analog converter (RFDAC) for upconversion. A phase of a local oscillator (LO) signal supplied to the RFDAC is selected according to a quadrant determined by signs of a given pair of I and Q modulated signal samples. The selected phase of the LO is supplied to the RFDAC for use in upconverting the sequence of I and Q modulated signal samples. In another embodiment, a current steering DAC is used for directly upconverting the I and Q modulated signal samples. A clock signal at four times the LO frequency is supplied to a counter and to the current steering DAC. One of the I and Q modulated signal samples and negative I and negative Q modulated signal samples is selected for supply to an input of the current steering DAC based on a count state of the counter. | 05-08-2014 |
20140146917 | TRANSMITTER WITH PRE-DISTORTION MODULE, A METHOD THEREOF - Aspects of the disclosure provide a transmitter that includes a pre-distortion module and a phase controller. The pre-distortion module is configured to receive a first digital value and generate a first pre-distorted digital value based on the first digital value and a corresponding angle. The first digital value is a combination of an in-phase component and a quadrature component of a signal for transmission. The phase controller is configured to control an amplifier to drive a current according to the first pre-distorted digital value and phase information in relation to the first digital value during a first phase range of a carrier signal determined at least partially based on the angle. | 05-29-2014 |
20140219391 | HIGH DYNAMIC RANGE AMAM PREDISTORTION - A predistortion function is evaluated with in-phase (I) and quadrature (Q) data words as arguments, while additive I and Q data words are generated in accordance with a comparison of the I and Q data words with a full scale value that generates maximum current in a digital power amplifier. The additive I and Q data words are added to the computed I and Q data words to produce predistorted I and Q data words. The predistorted I and Q data words are provided in a sequence to the digital power amplifier, which generates a corresponding radio-frequency (RF) analog signal. | 08-07-2014 |
20140327473 | METHOD AND APPARATUS FOR A PROGRAMMABLE FREQUENCY DIVIDER - A dual-edge triggered variable frequency divider for use in digital frequency synthesis is disclosed. The variable frequency divider utilizes a multiphase clock and a logic unit, including both positive and negative edge triggered unit delay elements connected in parallel. The variable frequency divider generates a clock pulse from a signal source that corresponds to an input value from a logic unit, generates a next input value by the logic unit based on the input value and a frequency control word, and transmits the next input value from the logic unit to the signal source in response to the clock pulse. The multiphase clock is configured to generate the clock signal in response to the falling edge of the first pulse of the clock signal. Iteratively selecting signals by this process results in an observed output frequency of f | 11-06-2014 |
20140362955 | ADAPTIVE IQ IMBALANCE ESTIMATION - A transceiver includes an input node to receive an input signal having in-phase (I) data and quadrature (Q) data, the input signal including several data samples. A correlation module determines an autocorrelation of the in-phase data, an autocorrelation of the quadrature data, a difference between the autocorrelation of the in-phase data and the autocorrelation of the quadrature data, and a cross correlation between the in-phase data and the quadrature data. An averaging module determines an average of the difference between the autocorrelation of the in-phase data and the autocorrelation of the quadrature data, and an average of the cross correlation between the in-phase data and the quadrature data, in which the averages are determined over a specified number of data samples. A compensation module, based on the average difference between the autocorrelation of the in-phase data and the autocorrelation of the quadrature data, and the average cross correlation between the in-phase data and the quadrature data, determines compensated in-phase data and quadrature data having reduced IQ mismatch. | 12-11-2014 |
20150023451 | PREDISTORTION FACTOR DETERMINATION FOR PREDISTORTION IN POWER AMPLIFIERS - A baseband signal is generated as a sequence of complex sample values at a predetermined sample rate. A sample of the baseband signal is captured as is a sample of an output signal generated by a power amplifier from the captured sample of the baseband signal. Complex values are iteratively assigned to a complex factor intended for predistorting data such that the product of the baseband signal sample and the complex factor converges towards equivalence with the output signal sample with each iterative assignment of the complex values to the complex factor. The complex factor is stored in memory at an address associated with the value of the captured baseband signal sample. | 01-22-2015 |
20150024699 | Convergence Estimation for Iterative Predistortion Factor Determination for Predistortion in Power Amplifiers - To estimate complex factors for use in predistortion of a power amplifier, a complex factor is selected a set of complex factors a computation interval. A solution value is estimated for the selected complex factor during the computation interval by an iterative computation that constrains the estimated solution value towards a final solution value over an arbitrary number of iterations that is not bounded by the duration of the computation interval. A cumulative error in the estimated solution value is computed at each iteration over consecutive computation intervals. From the cumulative error, it is determined whether a convergence criterion is met and, if so, the estimating is terminated. The termination occurs independently of the solution value estimated for any one of the complex factors in the set. | 01-22-2015 |