Abstract: A power amplifier system uses adaptive distribution of signals through an amplifier architecture of parallel amplifier stages. For example, the power amplifier system can adjust the operation of individual amplifier stages in the amplifier arrangement, for example to reduce power handling capability of the amplifier stages based on information of the signal to be amplified by the amplifier arrangement, such as the power level. To take advantage of the adjusted operation of the amplifier stages, the power amplifier system uses a variable power divider to reapportion the input signal power among the amplifier stages and at least one variable combiner to adaptively combine amplified signals from the amplifier stages in changing proportions. As such, the power amplifier system is reconfigurable and/or can adapt to changing conditions to provide improved performance and/or efficiency.

Abstract: A frequency mixing system provides an expanded dynamic range when compared to the dynamic range(s) of an individual mixer(s) that make up the arrangement. The frequency mixing system uses a feed-forward arrangement to reduce the distortion emanating from a single mixer due to a signal power level which would result in a frequency converted signal outside the dynamic range of the mixer. For example, the frequency mixing system splits an input signal onto a first path and a second path. On the first path, a first mixer frequency mixes the signal to produce a frequency converted signal with distortion, such as intermodulation distortion. On the second path, the amplitude of the signal is attenuated then frequency mixed by a second mixer to produce a frequency converted signal with a low and/or insignificant level of distortion.

Abstract: A frequency mixing system that provides an expanded dynamic range when compared to the dynamic range(s) of an individual mixer(s) that makes up the frequency mixing system. The frequency mixing system adjusts the amplitude of an input signal to be frequency mixed to produce a frequency converted signal with an acceptable and/or lower (when compared to the amplitude of intermodulation distortion produced by mixing the input signal without amplitude adjustment) amplitude of intermodulation distortion. If the input signal were frequency mixed without the amplitude adjustment, an unacceptable and/or higher level of intermodulation distortion would result (when compared to the corresponding intermodulation distortion if the amplitude-adjusted signal were mixed by an individual mixer). Adjusting the amplitude of the input signal creates an adjusted signal with signal distortion on the first path.

Abstract: An A/D system provides an expanded SFDR when compared to the SFDR of individual A/D(s) that make up the A/D system. In response to an analog input signal whose amplitude would result in an narrower SFDR for a first A/D, the A/D system uses an amplitude adjuster which receives the analog input signal and produces an amplitude-limited signal with resulting signal distortion to the first A/D. By amplitude-limiting the analog input signal, the A/D system produces the resulting signal distortion but reduces or "clips" the amplitude of the analog input signal, thereby improving the SFDR performance of the first A/D by reducing the spurious distortion produced by the first A/D. The signal distortion resulting from the amplitude adjustment is routed to a second A/D. The first A/D converts the amplitude-limited analog signal to a digital signal with an expanded SFDR due to the lower amplitude of the adjusted analog signal.

Abstract: A modularly-partitioned feedforward multicarrier linear RF power amplifier is described. The circuitry and components of the power amplifier are segregated into physically-separate modules in accordance with several criteria. In one embodiment, the power amplifier is segregated into a RF power module, a linearizer module and a DC power supply module. The RF power module includes power- and frequency-dependent components and generally varies with the carrier frequency and output power requirements for a specific application. The linearizer module includes circuitry and components that are substantially power- and frequency-independent. As such, the linearizer module is substantially invariant and a single design may be used for virtually any application. The DC power supply module includes circuit and components that are substantially frequency independent but somewhat power dependent.

Abstract: A control system comprising an electrical circuit that produces distortion where the electrical circuit has a frequency band of operation. A pilot modulated carrier signal is generated and is cause to traverse across the frequency band of operation of the electrical circuit. Information obtained from the traversing pilot modulated carrier signal when it is determined that there is no interference between any signal applied to or generated by the electrical circuit. The information is used by the control system to substantially cancel the distortion.