Abstract: A method of reducing distortion in the output of an amplifier is provided. The method comprises subtractively combining an error signals with the appropriate phase shift with input signals to be amplified. The error signal being generated by subtractively combining a fed-forward portion of the input signal with a portion of the fed-back amplified output signal, and signal processing applied to it between its generation and application to correcting the input signal in the baseband domain. The error therefore being down-converted, filtered, and up-converted in the feedback path. The filtered baseband error signal components providing inputs to a controller which adjusts active elements of the amplification and feedback path in order to minimize the distortion within the output of the amplifier.

Abstract: A method of reducing distortion in the output of an amplifier is provided. The method comprises subtractively combining baseband error signals with the appropriate phase shift with baseband input signals, the baseband error signals generated by subtractively combining delayed fed-forward portions of the baseband input signals with baseband converted portions of a fed-back amplified output signal, the amplified output signal being a distorted replica of combined up-converted baseband input signals. The baseband error signals being filtered prior to the combining function, and also providing inputs to a controller which adjusts active elements of the amplification and fed-back paths in order to minimize the distortion within the output of the amplifier.

Abstract: A method of reducing distortion in the output of an amplifier is provided. The method comprises subtractively combining baseband error signals with the appropriate phase shift with baseband input signals, the baseband error signals generated by subtractively combining delayed fed-forward portions of the baseband input signals with baseband converted portions of a fed-back amplified output signal, the amplified output signal being a distorted replica of combined up-converted baseband input signals. The baseband error signals being filtered prior to the combining function, and also providing inputs to a controller which adjusts active elements of the amplification and fed-back paths in order to minimize the distortion within the output of the amplifier.

Abstract: A method of suppressing interference from remote transmitters operating to a first standard having frequencies overlapping those for a receiver operating to a second standard is provided. Such interference being increasingly common as a result of the deployment of multiple wireless transceivers within electronic devices either supporting multiple international standards, such as WiFi and WiMAX, or within typical wireless environments. Advantageously, the invention presents a means of actively cancelling interference from transmitters operating within the same frequency range as defined by the standard. The active cancellation accordingly allows improved performance for systems with very low received signal powers, such as GPS, in addition to wireless data communications standards.

Abstract: A method of suppressing interference from a transmitter operating to a first standard to a local receiver operating to a second standard is provided. Such interference being increasingly common as a result of the deployment of multiple wireless transceivers within electronic devices supporting multiple international standards, such as WiFi and WiMAX. Advantageously, the invention presents a means of actively cancelling interference both from transmitters operating within the same frequency range as defined by the standard as well as those operating in different frequency ranges. The active cancellation accordingly allows improved performance for systems with very low received signal powers, such as GPS, in addition to wireless data communications standards.

Abstract: A first signal conditioning circuit is formed from a first portion, a second portion and a third portion. Signal conditioning functions of each of these portions are facilitated by a predetermined type of integrated semiconductor die within which they are formed. Two different semiconductor dies are thus provided for facilitating integration of the first through third signal conditioning portions therein. Wire bonds are provided between the two different semiconductor dies in order to form circuit paths between the different first through third portions. The signal routing using between the two different semiconductor dies provides for completing of the first signal conditioning circuit having a first signal conditioning function. For example, circuits such as interstage matching circuits are disposed on a different semiconductor die than power amplifier circuits.

Abstract: A cable tuner front end circuit is disclosed for receiving a radio frequency television input signal and for selectively amplifying the signal in dependence upon a predetermined level of the tuner circuit output signal. The tuner front end circuit having first and second radio frequency paths, where in dependence upon the predetermined level of the output signal, the input signal either propagating along the first path without amplification or the input signal propagating along the second path with low noise amplification. Such that, when amplification is not required the amplifier circuit is disabled thereby offering a savings in tuner circuit power consumption.

Abstract: A novel method of enhancing power amplifier linearity is disclosed. The invention is for use within a transceiver system and provides a method in the digital domain for predistorting a digital modulated signal to compensate for the non-linearity properties of the power amplifier and other components within the transmitter system. The RF output signal of the transmitter circuit is sampled and the corresponding amplitude and phase are detected using a receiver circuit. In dependence upon the amplitude and phase information, a look-up table is indexed to select the predistortion data and predistortion of the digital modulated signal occurs within the predistortion circuit.

Abstract: A novel transmitter circuit is disclosed for receiving of an input signal and for providing of an amplitude increased RF output signal. Pluralities of switching power amplifiers are disposed along two signal propagating circuit branches and utilized for increasing a magnitude of the input signal, to form an output signal, which is a magnitude increased version of the input signal. Each of the switching power amplifiers utilizes switching elements having various magnitude increasing capacity and coupled to a control circuit for each being switchably selectable for providing of the magnitude increase to the input signal.

Abstract: Systems and methods are provided for a stacked die configuration of a high isolation switch and a rejection filter where transmit and receive signals are desired to have a high out-of-band rejection and a low loss band-pass region. In some aspects of the invention the high isolation switch is a double pole double throw switch modified to operate as a high isolation single pole double throw (SPDT) switch. In some aspects of the invention the high isolation switch is a conventional high isolation SPDT switch. The switch is mounted on a low profile rejection filter having metallization on a portion of an outer surface of the rejection filter. The metallization on the outer surface of the rejection filter provides an AC ground layer in close proximity to the switch that provides a short coupling path between the switch and the AC ground. The resulting switch-filter component also results in a smaller footprint than if the two devices were mounted individually and/or adjacently.

Abstract: A collector boost circuit is disclosed for providing a first voltage in a first mode of operation to a power amplifier, and a second voltage in a second mode of operation to the power amplifier. The collector boost circuit uses a switch and an indicator signal for triggering the switch between the first and the second mode of operation. The second voltage is a boosted voltage greater than the first voltage and is provided during peak excursions through a boost capacitor.

Abstract: A collector boost circuit is disclosed for providing a first voltage in a first mode of operation to a power amplifier, and another voltage in a second mode of operation to the power amplifier. The collector boost circuit uses an indicator signal derived by an RF detector to switch between the first and the second mode of operation. The another voltage is a boosted voltage greater than the first voltage and is provided when required during peak excursions to prevent amplifier clipping through a boost capacitor. The another voltage is continuous and varies in accordance with the detected peak signal amplitude.

Abstract: A current-mirror circuit for monolithic integration in semiconductor microwave circuits is presented which overcomes the detrimental aspects of the emitter-follower current mirror resulting in improved accuracy and stability of the current mirror even under low voltage operation of circuits with high emitter-bias voltages such as GaAs. Advantageously the circuit can be implemented solely with NPN transistors and resistors allowing the circuit to be compatible with the reduced manufacturing processes and design options on high frequency materials such as GaAs and InP. The invention can be applied to low emitter-bias voltage materials such as Si and SiGe to offer increased accuracy and stability, and lower power supply levels.

Abstract: Within an amplifier circuit having an amplifying transistor, a boost voltage is presented at a port of the transistor. The amplifying transistor has a base, an emitter and a collector or a gate, a source, and a drain. A capacitor is provided in electrical communication with the transistor. A voltage source is provided for providing one of the collector and the source with a first voltage and for in a first mode of operation charging the first capacitor. Also within the circuit is a switch for switching between the first mode of operation and a second other mode of operation wherein the first capacitor and the voltage source cooperate to provide a voltage at one of the collector and the source in excess of the first voltage.

Abstract: An electronic module that operates at various radio frequency standards is provided. The module includes a first integrated circuit die formed in a first semiconductor substrate and manufactured using a first semiconductor process. Disposed within the first integrated circuit is the first signal conditioning circuit for performing a function and a first ancillary circuit. The first ancillary circuit electrically coupled to the first signal conditioning circuit for use by the first signal conditioning circuit during operation thereof. Also within the module is a second integrated circuit formed in a semiconductor substrate, disposed within the second integrated circuit is a second signal conditioning circuit. The second signal conditioning circuit being electrically coupled to the first ancillary circuit such that during operation the first ancillary circuit is connected to either one of the first signal conditioning circuits or one of the second signal conditioning circuits.

Abstract: Currently tuner circuits maintain normal power consumption while they are receiving RF signals and do not have provisions therein for disabling portions of their circuitry for reducing of power consumption. For example, during changing of channels, portions of the tuner are not used while the tuner is waiting for channel data. Thus, disabling portions of the circuit while the tuner is waiting for data serves to reduce power consumption of the tuner. Furthermore, tuner power consumption is reduced by determining whether a signal input to the tuner circuit requires amplification or not, or whether linearity in the amplifier can be sacrificed by a reduction in amplifier gain. Thus, a tuner circuit is provided that has control loop circuitry to execute control loops for controlling the gain and linearity of the tuner, as well as power consumption of circuitry therein.

Abstract: An integrated front end filter for a tuner provides an array of from several to a multitude of passbands, each for passing at least one but less than all channels designated in a band of frequencies. Each passband is exclusively selectable. The integrated front end filter can include at least one active filter unit with an active reactance element in either of fixed and variable filter configurations and a decoder coupled to said at least one active filter unit and being responsive to a control signal for selecting a one of the passbands. In one example, a multitude of active filter units of fixed filter configuration provide the multitude of passbands. In another example, a plurality of data corresponds to a like plurality of selectable passbands in combination with a filter element of the variable filter configuration. Each data is stored at a predetermined location and reproduced in response to a corresponding control data signal from a tuner controller.

Abstract: Power supply noise affects the performance of many amplifier circuits. Power supply noise rejection circuits are typically used in conjunction with amplifier circuits to reduce the effects of the noise. Unfortunately, the main issue with a transimpedance amplifier (TIA) is that it has a single input port and a single output port, and the output ports are often required to be of a differential type in order to interface with a differential input post amplifier circuit. As a result, the conversion from single input port operation to a dual input port configuration for differential operation is often the cause of poor power supply noise rejection. A circuit is thus provided that overcomes the limitations in the prior art by providing a differential TIA for use with a filter circuit and differential amplifier that overcomes the limitations of the prior art.

Abstract: A dual output voltage regulator circuit is disclosed. The output voltage regulator has a first FET and a second FET. A current source responsive to the regulated output voltage provides a current drive to the gate of the first FET in a first mode of operation and to the gate of the second FET in a second mode of operation. Further, the circuit employs switches for switchably selecting between the first mode of operation and the second mode of operation.

Abstract: A collector boost circuit is disclosed for providing a first voltage in a first mode of operation to a power amplifier, and a second voltage in a second mode of operation to the power amplifier. The collector boost circuit uses a switch and an indicator signal for triggering the switch between the first and the second mode of operation. The second voltage is a boosted voltage greater than the first voltage and is provided during peak excursions through a boost capacitor.