Indirect learning predistortion linearized system based on Volterra series

Abstract

The invention belongs to the field of digital communication distortion processing, in particular to an indirect learning predistortion linearized system based on Volterra series, comprising a predistortion signal generating module, a predistortion signal processing module, a feedback module and a parameter identification module. After the predistortion signal processing module processes a predistortion signal, an input signal of a radio-frequency power amplifier is obtained; after a small part of power in an output signal of the radio-frequency power amplifier is attenuated, the output signal enters the feedback module; after the feedback module processes a feedback signal, an input signal of the parameter identification module is obtained; the parameter identification module compares an output signal of same with the predistortion signal so as to obtain an error signal; and the error signal is gradually reduced and returned to zero by adjusting the parameters in the identification module and a predistorter. The invention has high stability and strong adaptive ability; the stability of the system does not need consideration, and meanwhile, the system can process multi-carrier signals; and the invention has good intermodulation distortion improvement effect and large adjustable range.

Description

technical field [0001] The invention belongs to the field of digital communication predistortion processing, and in particular relates to a Volterra series indirect learning type predistortion linearization system based on radio frequency power amplifier linearization technology. Background technique [0002] With the development of digital communication technology and the maturity of 3G technology, frequency band resources are becoming more and more precious. Therefore, it is required to increase the utilization rate of the frequency band, which urgently requires the power amplifier to have good linearity. In a mobile communication system, in order to ensure that the mobile communication system has signal coverage within a certain range, a power amplifier is usually used to amplify the signal before the signal is transmitted through the radio frequency front end and the antenna system. The linearity of the power amplifier directly affects the quality of the transmitted and...

AI Technical Summary

Problems solved by technology

Among them, the advantage of feedforward technology is that it has stable performance and can improve the linearization index of the power amplifier, but it also has high cost, the change of device characteristics over time cannot be compensated, and the design of the loop is relatively complicated. Disadvantages: The power back-off method backs the working voltage from 1dB to the linear working area, so it has better linearity, but at the same time it also sacrifices the efficiency of the power amplifier, making the DC power consumption very large, which causes the heat dissipation of the successful radiator problem, and heat dissipation is a difficult point in the research of power amplifiers, so this technology has been gradually replaced by other linearization technologies

The negative feedback technology requires the input signal and the feedback signal to be at the same time, and the system itself has a delay, which is difficult to achieve from this point of view.

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