Abstract: The solution controls electric operational power to be fed to an amplifier. The control can be carried out, for instance, in accordance with a predetermined signal. The operational power is fed to the amplifier with a voltage source unit and a current source unit, and the operational voltage that the voltage source unit feeds to the amplifier is controlled. The current source unit feeds at least some of the operational electric current of the amplifier.

Abstract: The solution controls electric operational power to be fed to an amplifier. The control can be carried out, for instance, in accordance with a predetermined signal. The operational power is fed to the amplifier with a voltage source unit and a current source unit, and the operational voltage that the voltage source unit feeds to the amplifier is controlled. The current source unit feeds at least some of the operational electric current of the amplifier.

Abstract: An electronic circuit for adjusting a property of an input signal of a non-linear element is disclosed. A detector detects a strength of the input signal. An analog controller forms a control signal as a piecewise approximation of a non-linear dependency between the property and the strength of the input signal detected by the detector. An adjusting circuit adjusts the property of the input signal according to the control signal from a controller.

Abstract: An adjusting circuit for adjusting an amplitude of a radio frequency signal is disclosed. The adjusting circuit includes a plurality of terminals for input and output, a matching component having an effect on matching a signal input and a signal output to and from the terminals. The adjusting circuit also includes at least one adjustable resistance unit between the matching component and ground for changing a resistance of the input and the output of at least one terminal of the amplitude adjusting circuit. The adjusting circuit for adjusting an amplitude of a signal also may include a plurality of terminals for input and output, at least one pair of adjustable impedance units. Each pair of the adjustable impedance units is placed between a pair of input and output terminals. Each of the adjustable impedance units is coupled in parallel between a signal line and ground, and the impedance units of each pair have complementary reactances with respect to each other.

Abstract: An electronic circuit for adjusting a property of an input signal of a non-linear element is disclosed. A detector detects a strength of the input signal. An analog controller forms a control signal as a piecewise approximation of a non-linear dependency between the property and the strength of the input signal detected by the detector. An adjusting circuit adjusts the property of the input signal according to the control signal from a controller.

Abstract: The quality and efficiency of producing an amplified signal output from a feed-forward amplifier system having reduced distortion and noise is provided. Multiple adjusters are included in the signal cancellation loop of a feed-forward amplifier system so as to more accurately adjust the different frequencies within a frequency band. For example, in a multi-carrier feed-forward amplifier system two or more adjusters are provided in the signal cancellation loop so as to provide more accurate adjustment for the various carriers rather than relying on a single adjuster to adjust for all carriers. According to one variation of the invention, two adjusters are provided in the signal cancellation loop of a two carrier multi-carrier feed-forward amplifier system. Each of the two adjusters adjusts a respective one of the two carriers. The outputs of the adjusters are combined and input to a delay element in the signal cancellation loop.