Abstract: Linearizers can improve the linearity of power amplifiers by canceling or reducing amplitude of non-linearity components, (e.g., IM3, IM5, IM7, IM9, etc.) generated by the power amplifier. The linearizers can obtain samples of signals output by the power amplifier and process the samples to produce a canceling signal that is applied onto or into an output of the power amplifier. The canceling signal is generated such that when applied to the output of the power amplifier, the canceling signal cancels or reduces at least a portion of the non-linearity components produced by the power amplifier. A controller can improve the correction of the non-linearity components by executing one or more tuning algorithms and adjusting settings of the linearizer based on the results of the algorithm(s).

Abstract: Signals propagating from an aggressor communication channel can cause detrimental interference in a victim communication channel. A high input power cascaded filter canceller (“HIPCF”) can obtain a sample of the signal that imposes interference and process the sampled signal to generate an interference compensation signal that, when applied to the victim communication channel, cancels or suppresses the detrimental interference. The HIPCF canceller can include two or more cascaded filters, such as band-pass filters, that block or reduce amplitude of a signal outside the communication frequency band of a victim receiver. The HIPCF canceller also includes an I/Q modulator that receives the filtered signal and generates the interference compensation signal by adjusting or updating one or more aspects of the filtered signal, such as a gain, phase, or delay, based upon feedback from the victim receiver or a power detector and algorithms executed by the controller.

Abstract: An interference compensation circuit for suppressing in-band or nearby out-of-band interference in a shared antenna communication system. The communication system can include a first communication device having a transmitter for transmitting signals within a first frequency band and a second communication device having a receiver for receiving electromagnetic signals within a second frequency band. The second frequency band can be adjacent or overlapping the first frequency band. The communication system also can include an interference compensation circuit that receives samples of the signals transmitted by the transmitter and generate an interference compensation signal in response to adjusting amplitude, phase, and/or delay of the samples. The interference compensation signal can suppress interference imposed on the receiver by the signals transmitted by the transmitter when applied to a signal receive path of the receiver.

Abstract: Signals propagating from an aggressor communication channel can cause detrimental interference in a victim communication channel. One or more noise cancellers can generate an interference compensation signal to suppress or cancel the interference based on one or more settings. A controller can execute algorithms to find preferred settings for the noise canceller(s). The controller can use a feedback signal (e.g., receive signal quality indicator) received from a victim receiver during the execution of the algorithm(s) to find the preferred settings. One exemplary algorithm includes sequentially evaluating the feedback resulting from a predetermined list of settings. Another algorithm includes determining whether to move from one setting to the next based on the feedback values for both settings. Yet another algorithm includes evaluating a number of sample settings to determine which of the sample settings result in a better feedback value and searching around that sample setting for a preferred setting.

Abstract: Linearizers can improve the linearity of power amplifiers by canceling or reducing amplitude of non-linearity components, (e.g., IM3, IM5, IM7, IM9, etc.) generated by the power amplifier. The linearizers can obtain samples of signals output by the power amplifier and process the samples to produce a compensation signal that is applied onto or into a transmission path leading to the power amplifier's input. The compensation signal is generated such that when amplified by the power amplifier, the amplified compensation signal cancels or reduces at least a portion of the non-linearity components produced by the power amplifier. A controller can improve the correction of the non-linearity components by executing one or more calibration algorithms and/or one or more tuning algorithms and adjusting settings of the linearizer based on the results of the algorithm(s).

Abstract: A quadrature modulator and a method of calibrating same by applying a first test tone signal to an in-phase modulation branch input of the modulator and a ninety degree phase-shifted version of the first test tone signal to a quadrature modulation branch input of the modulator. The carrier leakage level in an output signal of the modulator is measured and in response base band dc offset voltages are adjusted to minimize the carrier leakage. A second test tone signal is applied to the in-phase modulation branch input and a ninety degree phase-shifted version of the second test tone signal to the quadrature modulation branch input. The level of an undesired upper sideband frequency component in the output signal is measured and in response base band gains the in-phase and quadrature modulation branches and a local oscillator phase error are adjusted to minimize the undesired side band.

Abstract: A signal selector enhancer suitable for portable electronic devices and base stations is disclosed. In one embodiment, the enhancer can include: a filter for receiving a signal from a first node, and for providing a filtered signal output therefrom, where the first node is coupled to a signal selector; and a noise canceller for receiving the filtered signal output, and for providing an adjusted filtered signal at a second node, where the second node is coupled to the signal selector, and where an operation of the signal selector is enhanced by the filter and the noise canceller arrangement.

Abstract: A signal filter and accompanying methods. In one embodiment, the filter includes a first mechanism for receiving a first signal. A second mechanism employs one or more modified representations of the first signal to cancel one or more frequency components of the first signal, yielding an output signal in response thereto. In a more specific embodiment, the first mechanism includes a splitter for receiving the first signal and splitting the first signal onto a first path and a second path. The second mechanism further includes one or more delay modules and one or more phase shifters in the first path and/or the second path. One or more controllable amplifiers are optionally included in the first path and/or the second path. The one or more delay modules, phase shifters, or amplifiers are responsive to one or more control signals from a controller. The controller is adapted to modify behavior of the second mechanism so that the filter is characterized by a desired frequency response.

Abstract: A filter controller. In one embodiment, the filter controller includes a first mechanism for providing an input signal to an adjustable filter. A second mechanism measures a response of the adjustable filter to the input signal and provides a second signal in response thereto. A third mechanism sets one or more parameters of the adjustable filter in response to the second signal. In a more specific embodiment, the adjustable filter includes one or more sub-filters, such as a canceller filter, which may be any filter that employs one or more portions or versions of a signal to selectively cancel one or more portions or versions, such as frequency components, of the same signal.

Abstract: A noise sampling detector suitable for portable electronic devices is disclosed. The detector may detect noise, transmitter signals, spurs, and/or interference. In one embodiment, a detector can include: a load portion; an antenna pattern shaping portion coupled to the load portion, where the antenna pattern shaping portion includes meandering segments of variable lengths and/or widths; and an impedance matching circuit coupled to the antenna pattern shaping portion.

Abstract: An antenna module with a detector and an associated canceller is disclosed. The detector may also detect interference and spurs. In one embodiment, an antenna module can include: an antenna configured to receive an electromagnetic signal in a signal path; an amplifier configured to amplify the received electromagnetic signal, and to provide the amplified signal at a first node; a filter configured to receive the amplified signal from the first node, and to provide a filtered signal output therefrom; and a noise canceller and a detector integrated in the signal path at the first node.

Abstract: A quadrature modulator and a method of calibrating same by applying a first test tone signal to an in-phase modulation branch input of the modulator and a ninety degree phase-shifted version of the first test tone signal to a quadrature modulation branch input of the modulator. The carrier leakage level in an output signal of the modulator is measured and in response base band dc offset voltages are adjusted to minimize the carrier leakage. A second test tone signal is applied to the in-phase modulation branch input and a ninety degree phase-shifted version of the second test tone signal to the quadrature modulation branch input. The level of an undesired upper sideband frequency component in the output signal is measured and in response base band gains the in-phase and quadrature modulation branches and a local oscillator phase error are adjusted to minimize the undesired side band.

Abstract: A quadrature modulator and a method of calibrating same by applying a first test tone signal to an in-phase modulation branch input of the modulator and a ninety degree phase-shifted version of the first test tone signal to a quadrature modulation branch input of the modulator. The carrier leakage level in an output signal of the modulator is measured and in response base band dc offset voltages are adjusted to minimize the carrier leakage. A second test tone signal is applied to the in-phase modulation branch input and a ninety degree phase-shifted version of the second test tone signal to the quadrature modulation branch input. The level of an undesired upper sideband frequency component in the output signal is measured and in response base band gains the in-phase and quadrature modulation branches and a local oscillator phase error are adjusted to minimize the undesired sideband.

Abstract: A transceiver has frequency generating means for generating a first signal at a first frequency. The frequency generating means has first tank means for resonating at the first frequency. The transceiver further has frequency multiplication means for multiplying the first signal by an integral multiple of a fundamental frequency of the first signal. The frequency multiplication means has second tank means for resonating at a harmonic frequency of the fundamental frequency, the harmonic frequency being determined by the integral multiple. The frequency multiplication means has output means for outputting a second signal at the harmonic frequency. The first tank means is highly frequency selective around the first frequency, and the second tank means is highly frequency selective around the harmonic frequency. The transceiver has tuning means for simultaneously tuning the first and second tank means, and has up/down-conversion means for up/down-converting the second signal.

Abstract: A digital interface for a wireless communication system is provided with a reduced number of connectors. A first connector conveys a data signal between the radio frequency and the baseband circuitries. The data signal represents a digital baseband signal received or to be transmitted over the wireless network. The data signal is a multilevel data signal and conveys more than one bit of a sample of the digital baseband signal at a time. The radio frequency circuitry synchronizes the transfer of the data signal with a synchronizing clock provided by the baseband circuitry. The baseband circuitry controls the operational mode of the communication system via a control signal representative of command to the radio frequency circuitry. The control signal represents commands of various lengths thereby enabling fast transfer of critical commands.

Abstract: In a method of calibrating a quadrature transmitter, a first calibration signal is injected into an in-phase transmit branch of the quadrature transmitter, and a second calibration signal is injected into a quadrature transmit branch of the quadrature transmitter. The first and second calibration signals are injected before performing up-conversion in the transmitter and are produced by first and second digital signals. A detector detects an up-converted signal. The detected up-converted signal is digitized. The in-phase and quadrature transmit branches are calibrated by alternately determining the first and second calibration signals while at least varying respective most significant bits of the first and second digital signals, upon said varying the at least most significant bits keeping calibration bit values that correspond to minimum values of the digitized detected up-converted signal.

Abstract: A transceiver has frequency generating means for generating a first signal at a first frequency. The frequency generating means has first tank means for resonating at the first frequency. The transceiver further has frequency multiplication means for multiplying the first signal by an integral multiple of a fundamental frequency of the first signal. The frequency multiplication means has second tank means for resonating at a harmonic frequency of the fundamental frequency, the harmonic frequency being determined by the integral multiple. The frequency multiplication means has output means for outputting a second signal at the harmonic frequency. The first tank means is highly frequency selective around the first frequency, and the second tank means is highly frequency selective around the harmonic frequency. The transceiver has tuning means for simultaneously tuning the first and second tank means, and has up/down-conversion means for up/down-converting the second signal.

Abstract: In a method of calibrating a quadrature transmitter, a first calibration signal is injected into an in-phase transmit branch of the quadrature transmitter, and a second calibration signal is injected into a quadrature transmit branch of the quadrature transmitter. The first and second calibration signals are injected before performing up-conversion in the transmitter and are produced by first and second digital signals. A detector detects an up-converted signal. The detected up-converted signal is digitized. The in-phase and quadrature transmit branches are calibrated by alternately determining the first and second calibration signals while at least varying respective most significant bits of the first and second digital signals, upon said varying the at least most significant bits keeping calibration bit values that correspond to minimum values of the digitized detected up-converted signal.