Abstract:
A high-linearity linearizer system includes a multi-stage linearizer circuit formed by cascading multiple linearizer circuits. The multi-stage linearizer circuit is configured to pre-distort an input signal to generate a pre-distorted signal. A non-linear high-power amplifier (HPA) having non-linear characteristics is coupled to the multi-stage linearizer circuit and is configured to amplify the pre-distorted signal. Pre-distortion characteristics of the multi-stage linearizer circuit are configured to counter the non-linear characteristics of the non-linear HPA and to compensate a non-linearity of the non-linear HPA to achieve a desired level of linearity.
Abstract:
The invention provides a power amplifier (300) arranged to receive an input power signal (Pin) at an input port of a three port Input Power Splitter, IPS. The IPS is arranged to deliver a main input power signal (P1) to a main amplifier branch and an auxiliary input power signal (P2) to an auxiliary amplifier branch. The power amplifier (300) is arranged to deliver an output power signal (Pout) to a common node. A Phase Compensation Network, PCN, is arranged in the main amplifier branch. A Nonlinear Driver Amplifier, NDA, is arranged in the auxiliary amplifier branch. The NDA is arranged to increase the gain in the auxiliary amplifier branch. The invention also provides a corresponding method and a node in a wireless communication system comprising the power amplifier.
Abstract:
Apparatus for amplifying an input signal having an input signal power includes a power amplifier (22), which is adapted to amplify an intermediate signal so as to generate an output signal, and which is characterized by a non-linearity. A non-linear filter (24) is coupled to decompose the input signal into a series of input signal components, each such component proportional to a product of the input signal by a respective integer power of the input signal power, and is adapted to filter the signal components responsively to the non-linearity so as to generate the intermediate signal for input to the power amplifier (22).
Abstract:
A method for a predistortion linearization of a branched signal for a RF amplifier, comprising supplying a branched signal to at least one input terminal (2); distributing power of the input signal present on at least one input terminal (2) to a plurality of parallel branch-circuits (16, 18, 20) as a branched signals by a power distributing circuit (4); controlling a phase parameter and an amplitude parameter of the branched signals by at least one nonlinear branch-circuit (18, 20); controlling a phase parameter and an amplitude parameter of the branched signals by at least one linear branch-circuit (16); combining output branched signals of at least one nonlinear branch circuit (18, 20) with the output branched signals of at least one linear branch circuit (16) by a power combining circuit (12); providing an output branched signal of the power combining circuit (12) on at least one output terminal (14). Furthermore, a circuit for a predistortion unit linearizing a signal for a RF amplifier and a layout of a predistortion linearization of a signal for a RF amplifier are disclosed.
Abstract:
The invention concerns a device for linearizing a microwave signal subsequently submitted to an amplification stage, consisting of a free wave tube or a solid-state amplifier. A resolver consisting of a circulator and a Schottky-barrier diode adapted to low amplitude signals generates, with less expensive assembling and adjusting components, a compression channel and an expansion channel with excellent insulation and stability performances. The invention is applicable in telecommunications or to radar.
Abstract:
A predistortion linearizer circuit comprising an amplitude distorting part (AM/AM) and a phase distorting part (AM/PM). At least the phase distorting part (AM/PM) comprises broadband biasing means (51) and a non-linear transmission line (L51/D51 to L55/D55) responsive to them. The biasing means (51) are arranged to bias the non-linear transmission line (L51/D51 to L55/D55) to a substantially phase distorting area. The characteristics of the circuit can be changed by adjusting a biasing voltage (VB1) or by switching some of the diodes (D54, D55) inactive by activation signals (VA1, VA2). The amplitude distorting part (AM/AM) and the phase distorting part (AM/PM) can be similar in structure, but the diodes (D51 to D55) are partly forward-biased, whereby the losses caused by them decrease the amplitude of the signal.
Abstract:
The invention relates to a correcting device for automatically correcting a high frequency power amplifier. Said correcting device has a mechanism for generating a reference carrier from a measured input signal (7) of the high frequency power amplifier, and a first synchronous demodulator (8) for generating an input envelope curve from the measured input signal (7) and from the reference signal. The inventive device also has a second synchronous demodulator (9) for generating an inphase component of an output envelope curve from the measured output signal (6) of the high frequency power amplifier (3) and from the reference carrier, as well as a phase modifier (12) for displacing the phase of the reference carrier by 90 DEG . A third synchronous demodulator (10) generates a quadrature component of the output envelope curve from the measured output signal (6) of the high frequency power amplifier (3) and from the reference carrier which is by 90 DEG out of phase. A control device (24) generates an amplitude correction control signal and/or a phase correction control signal from the input envelope curve, from the inphase component of the output envelope curve and/or from the quadrature component of the output envelope curve. The modulation characteristic and/or phase characteristic of a correcting device (2) is set by the amplitude correction factor and the phase correction factor inversely to the modulation characteristic and/or the phase characteristic of the high frequency power amplifier (3).