Abstract: This invention covers a phase shifter-equalizer circuit including a purely resistive impedance, a purely reactive impedance, at least one of which adjustable, and a phase inverter device, which permit to adjust in a continuous way the phase between the output current and the input current, while maintaining the amplitude of the output current constant and substantially equal to the amplitude of the imput current versus phase and group delay variations between the two currents. Furthermore, continuous phase adjustment is achieved by adjusting one only parameter of the circuit.

Abstract: A predistorter for use in transmission systems which employ power amplifiers, employing traveling wave tubes or field effect transistors. Since these active components present a nonlinear characteristic, which introduce amplitude and phase distortion in the amplified signal, the distorter circuit operates to subtract the distortion products from the output signal. In the present arrangement, the subtraction takes place before amplifying the signal by means of generation of distortion products which will present the same amplitude and opposite phase of those that will be generated by the power amplifier in order to obtain an undistorted and amplified signal.