Power control method and device

Abstract

The invention discloses a power control device and method. The method comprises the following steps: performing TAGC (transmission automatic gain control) treatment on a pre-stored training sequence; performing CAGC (carrier automatic gain control) treatment on a signal on each carrier before multi-carrier superimposition, and performing interpolation filtration on the signal after the CAGC treatment to finish spectrum formation; performing spectrum shift on the signal after the spectrum formation; performing CFR (crest factor reduction) treatment on the signal after the multi-carrier superimposition; performing high-speed pre-distortion treatment on the signal after the CFR treatment according to the calculated DPD (digital pre-distortion) coefficient; performing digital automatic control gain treatment on the signal after the high-speed pre-distortion treatment; performing digital-to-analogue conversion on the signal after the digital automatic control gain treatment; performing PGC (programmable gain control) treatment on the signal after the digital-to-analogue conversion, wherein the signal enters a power amplifier and then is output; performing gain control on the signal coupled back by the power amplifier; and controlling the gain fed back to a DPD module. Meanwhile, the power adjustment of the feedback digital signal is finished by comparing the feedback digital signal power with the digital signal power after the pre-distortion.

Description

technical field [0001] The present invention relates to the technical field of communications, in particular to a power control method and device. Background technique [0002] Predistortion (DPD) can make the amplifier output higher power under the premise that the frequency spectrum meets the requirements. With DPD, base station equipment manufacturers can choose a lower-cost power amplifier (PA) to meet the design requirements, thereby reducing the cost of the base station; at the same time, due to the improved efficiency of the power amplifier, it also reduces the operator's operating costs. [0003] There are two important theories of PA: one is that PA is a system with memory, and the other is that PA is a nonlinear system. The essential difference between the two is that nonlinearity produces new spectrums, while memory only affects existing signal information. The third-order intermodulation distortion is the most serious nonlinear distortion produced by nonlineari...

AI Technical Summary

Problems solved by technology

[0013] In this way, there is a problem: when the DPD parameter estimation is completed, the impact of a large change in the signal (such as the power of the signal) is as follows: figure 2 shown

In fact, the size of the transmit power is directly related to the system load, and it may not be possible to immediately collect the transmit power of P max A sample of , therefore, needs to know if a P max What kind of consequences will be brought about by parameter estimation of samples, as shown in the solid line EstP2) and solid line EstP1) in the figure, when the transmit power is lower than the power of the estimated sample, the DPD coefficient is effective (each The left side of the black point), but once the transmitted power exceeds the power of the estimated sample, the DPD coefficient will be invalid, and the performance is that the ACP increases and exceeds the specified value

In fact, it is difficult for the training module to know the maximum output power of the power amplifier in real time, and if the current power used to estimate the coefficient is not the maximum power, the module will not be able to know what will be output by a signal with a higher power (such as shown to the right of the two black dots on the left in the figure)

Therefore, during the parameter estimation period of low-power signals, once a high-power signal appears, the performance of ACP may be worse than that without DPD: the signal range during training is too small, and the least squares method cannot be used to obtain the parameters suitable for high-power signals. coefficient of

[0016] In the prior art, pre-distortion processing is difficult to track the drift of analog gain, and there is no good way to effectively compensate for the drift of analog gain.

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