Signal feedback loop and method for predistorter, power amplification equipment

Abstract

The invention discloses a signal feedback loop and a method for predistorter, and power amplification equipment. The signal feedback loop comprises: a down converter for converting feedback signals downward into baseband signals or intermediate frequency signals, a first filer for filtering the baseband signals or the intermediate frequency signals to preliminarily inhibit main band signals among the signals, thereby outputting first filtering signals, an analog-to-digital converter for converting first filtering signals into digital signals from analog signals, a second filer for filtering digital signals to further inhibit the main band signals among the signals, thereby outputting second filtering signals, a power calculator for calculating the out-of-band power of the feedback signals according to the second filtering signals; and a coefficient updating controller for updating the coefficient of the predistorter according to the out-of-band power. With the technology scheme of the invention, the dynamic scope requirement of analog-to-digital conversion and the complexity of simulation circuits can be reduced by shifting part of the simulation loop complexity to digital field and utilizing two-level filtering structure.

Description

technical field [0001] The invention relates to a nonlinear device, especially a digital predistortion linearization technology of a power amplifier, in particular to a signal feedback loop and method for a power amplifier predistorter. Background technique [0002] As the core component of the analog communication system, the power amplifier's low power consumption design or high efficiency design has always been a hot issue. The digital baseband predistortion method uses the feedback distortion information to pre-compensate the nonlinear characteristics of the amplifier at the sending digital end, and it is relatively easy to realize adaptive and high-bandwidth nonlinear compensation, and it has become one of the first choices of the predistortion method. [0003] According to the type of feedback information, predistorters can be divided into vector method and scalar method. [0004] The so-called vector method is to completely retain the amplitude and phase information ...

AI Technical Summary

Problems solved by technology

Although this scheme has few analog devices, it has higher requirements on AD, such as image 3 as shown in (b)

The dynamic range of AD (if 60dB is considered, then at least the AD of the effective number of bits (ENOB)=10 bits) and the sampling rate (if the 5th harmonic distortion is considered, then 5 times the upsampling rate is required) There are very high requirements, such ADs are often expensive, and the clock rate in the digital domain is high

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