LTE TDD RRU peak-to-average ratio statistical method based on FPGA

Abstract

The invention provides an LTE TDD RRU peak-to-average ratio statistical method based on a FPGA. In a remote radio unit, a CPU configures TDD time slot information and the FPGA detects a frame header signal; the maximum PAR value PAR_max of the current TDD frame signal is detected, including statistics of the maximum power C of 10000 data before the current moment and the sum D of power of 10000 data before the current moment, and the PAR value of each moment in the current TDD frame signal is detected one by one; and the CPU takes out the PAR_max value out of the FPGA and converts the PAR_max value so as to obtain the peak-to-average ratio of the current TDD frame signal. With application of the technical scheme, the PAR value before arrangement of a power amplifier or the PAR value outputted by small signals can be simultaneously calculated without a frequency spectrograph or limitation of bandwidth so that operation is simple, convenient and flexible; and statistics of the peak-to-average ratio is realized by using the FPGA logic so that speed is high and efficiency is high.

Description

technical field [0001] The present invention relates to the technical field of communication, in particular, relates to a peak-to-average ratio detection method of an LTE TDD RRU transmission link. Background technique [0002] LTE is the long-term evolution of 3G, which is currently called 4G. In LTE, the multi-carrier multiple access method OFDMA is mainly used for the downlink. The main advantages of this are: strong anti-multipath fading ability; high spectrum efficiency; reception The machine design is mature and reliable. However, since OFDMA adopts multi-carrier technology, the peak-to-average ratio is relatively high, so the DPD performance and the linearity requirements of the power amplifier are relatively high. Therefore, the peak-to-average ratio PAR is a very critical and important indicator in the system design of LTE RRU, and it directly affects the power amplifier. The determination of the 1db compression point of the module, the ACPR value, the efficiency o...

AI Technical Summary

Problems solved by technology

The PAR at the probability of 0.01% is generally called the peak factor. Since the dynamic range of the general power amplifier is limited, the signal with a relatively large peak-to-average ratio can easily enter the nonlinear region of the power amplifier, resulting in a nonlinear signal. Distortion, causing obvious spectrum spread interference and in-band signal distortion, resulting in the degradation of the overall system performance

[0004] The traditional method of measuring the peak-to-average ratio is to lead a test point at the entrance of the power amplifier or the exit of the small signal, and use a spectrum analyzer to measure the peak-to-average ratio of the modulated signal at a probability of 0.01%. This method has the following limitations: first , you need to use a spectrum analyzer to get the test results; second, for broadband signals above 20M, etc., the spectrum analyzer needs a high VBW to accurately give the PAR value, and the VBW of many spectrum analyzers does not have such a high accuracy

[0010] 6. DPD (Digital Pre-Distortion) digital pre-distortion

Images