Method for collecting data in digital pre-distortion system

Abstract

The invention discloses a method for collecting data in a digital pre-distortion system. The method comprises the following steps that (1) a parallel processing device collects emitting signals and samples the collected emitting signals, and a serial processing device determines the start position of frames; (2) the serial processing device searches for the largest value to determine the start position of the frames and transmits the synchronous start position of the frames to the parallel processing device; (3) the parallel processing device starts a long-time histogram statistic module to count amplitude distributions of all frames of the emitting signals; (4) the parallel processing device collects the emitting signals, stores the emitting signals in short time duration, transmits the collected emitting signals and amplitude histograms counted in a long time period to the serial processing device; (5) the serial processing device receives the emitting signals in short time duration, calculates the distributions of the amplitude histograms, and compares the similarity of the distributions of the amplitude histograms and the amplitude histograms calculated in a long time period, if the similarity is higher than the threshold, a pre-distortion factor is calculated, and if the similarity is not higher than the threshold, the similarity is abandoned, and data are obtained from the parallel processing device again. The method has the advantages of being high in adaptability, and the like.

Description

technical field [0001] The invention relates to a data acquisition technology, in particular to a data acquisition method in a digital predistortion system. Background technique [0002] With the development of wireless communication, the signal bandwidth is getting wider and wider, and its envelope fluctuation and peak-to-average ratio are getting bigger and bigger, which puts forward higher linearity requirements for broadband signaling channels, especially mixers and power amplifiers. This is mainly because semiconductor devices have unavoidable nonlinear characteristics under large signals. When a broadband transmitter works in the nonlinear region, serious intermodulation components will be generated, and large spectrum leakage will be generated outside the band, so that it will not Comply with the requirements of 3GPP's emission spectrum template. [0003] How to improve the linearity of the system is an important problem to be solved in the broadband system. The most...

AI Technical Summary

Problems solved by technology

The main problem of this hardware implementation method is: because the interface speed of the serial processing device to receive data is relatively slow, and the time unit for the serial processing device to calculate the pre-distortion coefficient is seconds, while the speed of the pre-distortion processing is usually several Hundreds of MHz, which means that the serial processing device cannot calculate and update the pre-distortion coefficient in real time, so the serial processing device can only update the pre-distortion processing coefficient intermittently, that is, collect the input and output signals of a power amplifier to calculate the pre-distortion coefficient , and then pass the coefficients to the pre-distortion processing module, the whole process takes nearly one second, so the pre-distortion processing coefficients used by the current pre-distortion processing module are calculated from the input and output data of the power amplifier one second ago

However, the changes of modern mobile communication signals are very fast. Usually, the length of a frame is on the order of milliseconds. With the access and exit of users, the amplitude of mobile communication signals changes greatly. At the same time, due to the storage resources of parallel processing devices and serial processing devices However, the length of the data used to calculate the pre-distortion coefficient is usually only microseconds long, so collecting the optimal data and providing it to the serial processing device to calculate the pre-distortion coefficient is a key step to improve the performance of the pre-distortion, but the existing pre-distortion related patents This method is not yet provided in

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