Predistortion linearizer and application of the predistortion linearizer

Abstract

The invention discloses a predistortion linearizer. The predistortion linearizer comprises a first branch line coupler which is configured for inputting a signal by a first input end in a direction equal to an input signal, then directly outputting the signal by a first straight through end and outputting the signal from a first coupling end, wherein the signal output from the first coupling end has uniform amplitude with the signal output from the first straight through end, the direction of the signal output from the first coupling end is opposite to that of the signal output from the first straight through end. The predistortion linearizer also comprises a first nonlinearity generator which is configured for generating a curve of which amplitude and phase are extended at the same time and outputting a first way of signal; a second nonlinearity generator which is configured for generating the curve of which amplitude and phase are extended at the same time and outputting a second way of signal; and a power divider which is configured for synthesizing the first way of signal and the second way of signal and outputting the synthesized signal. Through application of the predistortion linearizer to linearity of a power amplifier, such as a travelling wave tube, the linearity can be improved greatly, and the predistortion linearizer has important engineering application value.

Description

technical field [0001] The invention relates to the field of power amplifiers, and further relates to a predistortion linearizer and a linearization method using the predistortion linearizer. Background technique [0002] With the development of wireless and satellite communication technology, the non-constant envelope modulation technology with high spectrum utilization rate has been widely used, but it also makes the modulated signal have a higher peak-to-average ratio, which affects the important nonlinearity in the system. Device - the linearity of the power amplifier puts forward higher requirements. When a power amplifier such as a traveling wave tube works in a saturated state, the efficiency is high and it can output high power, but the linearity at this time is poor, which will cause very serious distortion of the modulated signal, and then cause the signal constellation to be deformed and distorted. Spectrum regrowth, causing intersymbol interference and adjacent ...

AI Technical Summary

Problems solved by technology

[0004] The current linearizer developers have not deeply analyzed the influence of zero-bias junction capacitance and series resistance on the pre-distortion expansion curve in the diode SPICE (General Analog Circuit Simulator) model parameters, and have not given the principle of circuit board selection. There is blindness in the plate, the designed microstrip linearizer has the following problems in the K-band (18-27GHz), the absolute and relative bandwidth does not exceed 1.8GHz and 4%, and it is necessary to add isolators at the input and output ends.

Images