Abstract: Teachings herein schedule a data transmission in a variable bandwidth wireless communication system based on the power efficiency of a mobile node. One or more processing circuits, of the mobile node or a network node, determine the value of a control setting that defines a power efficiency configuration of the mobile node. In one embodiment, for example, the power efficiency configuration indicates the mobile node is configured to operate at the maximum power efficiency attainable without the data rate of the data transmission falling below a minimum data rate required by a quality of service. Regardless, the one or more processing circuits select from different possible bandwidths of the data transmission a bandwidth that supports a given data rate and that, according to a power efficiency model that models power efficiency of the mobile node for the different possible bandwidths, yields a power efficiency comporting with the power efficiency configuration.

Abstract: A level of power reduction for a transmitter arranged to transmit signals modulated according to one of a number of modulation configurations via radio channels in a digital wireless communications system is estimated. Modulation dependent data comprising a term calculated from a third order product of a signal modulated according to a modulation configuration are provided, and a power reduction estimate for transmission of signals modulated according to said modulation configuration is calculated there from. The modulation dependent data are provided to comprise, in addition to the term calculated from a third order product, at least one term calculated from a higher order product. Further, transmitter dependent data are provided, and the estimate is calculated from said modulation dependent and transmitter dependent data. Thus a more accurate method of determining a power reduction is achieved, which also allows different operating conditions for the transmitter to be considered.

Abstract: The invention relates to adjusting an input signal level of a Sigma-Delta converter. A control signal indicative of an input signal level to said Sigma-Delta converter is generated, and the input signal level to said Sigma-Delta converter is adjusted in dependence of said control signal. The control signal is generated as a signal indicating an operating condition of said Sigma-Delta converter. In this way, internal signals from the Sigma-Delta converter can be used to determine the state of the Sigma-Delta converter, i.e. whether it is operating within its operational input range or not, and whether it is close to the limits of the operational input range. This provides a simple, but accurate guidance of an automatic gain control upstream of the Sigma-Delta converter.

Abstract: Efficient carrier aggregation is enabled in a receiver employing a single frequency source, and dividing the frequency source by different frequency dividing factors to generate two or more RF LO frequencies. Received signals are down-converted to intermediate frequencies by mixing with the respective RF LO frequencies. By utilizing only a single high frequency source, embodiments of the present invention avoid spurious and injection locking issues that arise when integrating two or more frequency sources, and additionally reduce power consumption as compared to a multiple frequency source solution.

Abstract: A gain control circuit adjusts the signal level of a received signal responsive to the bandwidth a received signal and/or the delay spread of the channel in which the signal has propagated. The bandwidth and delay spread are evaluated to estimate the amount of signal variation that is expected due to fast fading. Adjustments to the signal level are then made to avoid clipping while at the same time ensuring that the dynamic range of a receiver component is efficiently utilized.

Abstract: A user equipment (UE) in a communication system can keep track of the cell/frequency deployment of a network operator preferred by the user, and based on the tracked information, the UE can build up its own user-specific Neighbor Cell List. When the UE is roaming, the UE does received-signal measurements according to cells and carrier frequencies identified in the broadcast Neighbor Cell Lists of the roamed-into network, but the UE also does received-signal measurements (with higher priority) according to the user-specific Neighbor Cell List that it has built up. Accordingly, a UE implementing a user-specific Neighbor Cell List analyzes its radio environment based on received signals and stores information about that environment, including user-preference information that prioritizes cells in the radio environment. The UE can then carry out cell search based on the stored environment and user-preference information.

Abstract: A method and apparatus for controlling the power consumption of a receiver based on current operating conditions is described herein. A receiver according to the present invention applies a received signal to a variable filter. The received signal includes a desired in-band signal. Depending on the current operating conditions, the received signal may further include one or more unwanted out-of-band blocking signals. A filter controller controls one or more operating parameters of the variable filter to maintain the power ratio at the filter output of the power of the blocking signal(s) to the in-band signal at or below a desired level. In so doing, the present invention controls the receiver power consumption while still providing the desired receiver performance.

Abstract: The invention relates to adjusting an input signal level of a Sigma-Delta converter. A control signal indicative of an input signal level to said Sigma-Delta converter is generated, and the input signal level to said Sigma-Delta converter is adjusted in dependence of said control signal. The control signal is generated as a signal indicating an operating condition of said Sigma-Delta converter. In this way, internal signals from the Sigma-Delta converter can be used to determine the state of the Sigma-Delta converter, i.e. whether it is operating within its operational input range or not, and whether it is close to the limits of the operational input range. This provides a simple, but accurate guidance of an automatic gain control upstream of the Sigma-Delta converter.

Abstract: This invention relates to adjusting a filter of a time-continuous Sigma-Delta converter arranged to convert an analog input signal (Sin) to a digital output signal. A control signal indicative of a gain of the filter is provided, and the gain of the filter is adjusted in dependence of the control signal. The control signal is provided from the digital output signal of the Sigma-Delta converter. In this way the performance of the Sigma-Delta converter can be improved in a simple way that requires no or few additional analog components, and the Sigma-Delta converter itself is used to adjust its performance. Using a signal from the digital domain of the Sigma-Delta converter is advantageous in that it is typically easier, faster and more precise to process signals in the digital domain.

Abstract: A polar modulation transmitter offers a split architecture for determining amplitude modulation path delay of the transmitter and comprises a split supply modulation circuit and a split power amplifier circuit. The split supply modulation circuit includes a common supply input and is configured to receive a common amplitude-modulation signal at respective signal inputs and output first and second modulated supply signals responsive to the common amplitude-modulation signal.

Abstract: A Cartesian Feedback-loop Signal Canceller (CFSC) recovers a signal of interest from a composite signal by cancelling a narrowband interferer from the composite signal. According to one embodiment, narrowband interference cancellation is performed by destructively combining a composite signal including a narrowband interference signal and a signal of interest with an estimate of the narrowband interference signal to generate an interference-compensated signal. A feedback signal is generated having Cartesian components derived from the interference-compensated signal. Cartesian components associated with the signal of interest are removed from the feedback signal to generate the narrowband interference signal estimate.

Abstract: A method and apparatus taught herein provide a digital-to-analog converter (DAC) for use in a conversion feedback path of a sigma-delta type analog-to-digital converter (ADC). The DAC uses current pulse shaping to generate a conversion feedback signal in each feedback cycle of the ADC that provides a consistent charge transfer for accurate digital conversion and has a controlled current pulse shape. In one or more embodiments, the DAC includes a capacitor circuit for charge storage and transfer and a (series) resistive circuit having variable resistance for current pulse shape control. In at least one embodiment, current pulse control limits a peak current of the conversion feedback signal, thereby reducing DC power consumption and gain-bandwidth (GBW) and slew rate requirements of the ADC's integration amplifier, and limiting residual (ending) current in each feedback cycle, which yields commensurate gains in (feedback cycle) clock jitter insensitivity.

Abstract: A method and apparatus taught herein reduce the peak-to-average ratio (PAR) of a complex-valued signal based on detecting peaks in the signal that are above a peak threshold, characterizing the detected peaks in Cartesian coordinates, generating cancellation pulses in Cartesian coordinates based on the detected peak characterizations. PAR reduction processing continues with canceling the detected peaks by combining the cancellation pulses with a correspondingly delayed version of the signal. Advantageously, peak detection may be performed in polar form using a computationally efficient peak detection algorithm that avoids calculation of the I and Q peak waveforms unless a signal peak beyond a defined threshold is present. In one or more embodiments, the generation and use of asymmetric and/or shaped cancellation pulses offers further performance advantages.

Abstract: A method and apparatus taught herein provide a digital-to-analog converter (DAC) for use in a conversion feedback path of a sigma-delta type analog-to-digital converter (ADC). The DAC uses current pulse shaping to generate a conversion feedback signal in each feedback cycle of the ADC that provides a consistent charge transfer for accurate digital conversion and has a controlled current pulse shape. In one or more embodiments, the DAC includes a capacitor circuit for charge storage and transfer and a (series) resistive circuit having variable resistance for current pulse shape control. In at least one embodiment, current pulse control limits a peak current of the conversion feedback signal, thereby reducing DC power consumption and gain-bandwidth (GBW) and slew rate requirements of the ADC's integration amplifier, and limiting residual (ending) current in each feedback cycle, which yields commensurate gains in (feedback cycle) clock jitter insensitivity.

Abstract: In communication systems where the channel is expected to vary during a communication burst, gain adjustments during the communication burst can be implemented by automatic gain control (AGC) in the receiver, with minimal performance degradation. These gain adjustments are successfully accommodated by virtue of suitable information-sharing between an AGC unit and a digital baseband part. The digital baseband part can direct the AGC unit appropriately to ensure that gain adjustments are implemented during time intervals that do not carry substantive communication information (e.g., guard intervals). In receivers that perform channel estimation in the digital baseband part, the AGC unit supports channel estimation by informing the digital baseband part about the timing of the gain adjustment. The AGC unit can also support channel estimation by informing the digital baseband part about the size of the gain adjustment.

Abstract: A polar modulation transmitter offers a split architecture for determining amplitude modulation path delay of the transmitter and comprises a split supply modulation circuit and a split power amplifier circuit. The split supply modulation circuit includes a common supply input and is configured to receive a common amplitude-modulation signal at respective signal inputs and output first and second modulated supply signals responsive to the common amplitude-modulation signal.

Abstract: Coupler-based amplifiers provide a measure of load mismatch based on the difference between the two output signal amplitudes from the amplifiers. This measure can be used to control variable matching networks (VMNs) or amplifier supply voltages to maintain constant distortion levels and high power transfer/efficiency and even to control output power. Load mismatch is measured by comparing the amplifier device output amplitudes and adjusting the circuit based on the comparison to counteract undesired behavior, such as increasing distortion levels.

Abstract: Coupler-based amplifiers provide a measure of load mismatch based on the difference between the two output signal amplitudes from the amplifiers. This measure can be used to control variable matching networks (VMNs) or amplifier supply voltages to maintain constant distortion levels and high power transfer/efficiency and even to control output power. Load mismatch is measured by comparing the amplifier device output amplitudes and adjusting the circuit based on the comparison to counteract undesired behavior, such as increasing distortion levels.

Abstract: Compounds of the general formula (I): are useful in treating chronic neurodegenerative diseases or conditions in mammals, such as Alzheimer's Disease, Parkinson's Disease, Huntington's Chorea and Multiple Sclerosis. In formula (I), a=3 or 4; b=3 or 4 provided that a+b?7; c is an integer from 1 to 5; d is 0 or 1.

Abstract: An electronic device has digital circuitry partitioned into digital circuit blocks, which are connected in series across a power supply, thereby sharing the available supply voltage between them. The device may be a battery-powered wireless communications device, including analog and digital circuitry, wherein the device includes a power supply, which provides a supply voltage which is supplied to the analog circuitry, and wherein the digital circuitry is separated into at least two blocks, which are connected in series across the power supply voltage.