Method for estimating power line system channel by using neural network

Abstract

The invention relates to a method for estimating a power line system channel by using a neural network, and belongs to the technical field of communication. The method comprises the following steps of: firstly, performing channel estimation in a neural network DnLSTM by using preamble orthogonal frequency division multiplexing (OFDM) symbol data; then, a neural network DnLSTM is adopted to generate a channel characteristic matrix of each symbol in frame control and frame load, and the channel characteristic matrix is used for channel equalization; and carrying out signal demodulation on the frame control and frame load symbols after channel equalization to obtain a log likelihood estimation value LLR of data carried by each OFDM symbol. According to the method for demodulating the communication signal by adopting the deep neural network, the robustness is good, specific algorithm processing does not need to be carried out on specific noise on the power line, and different power line noise environments are self-adapted through a large amount of training.

Description

technical field [0001] The invention belongs to the technical field of communication, and relates to a method for channel estimation of a power line system by using a neural network. Background technique [0002] Low-voltage power line broadband carrier carrier communication, or HPLC for short, is a power line carrier communication technology, which is mostly used in local communication (such as meter reading) in low-voltage station area electricity consumption information acquisition systems. The communication method adopts OFDM technology, and different communication frequency bands can be configured through different sub-carrier shielding schemes. , the sampling rate is 25MHz, the subcarrier spacing is 24.414KHz, the encoding algorithm is Turbo dual binary encoding, the physical block size includes 5 types such as PB16, PB72, PB136, PB264, PB520, and the code rate includes 1 / 2 and 16 / 18 two forms, there are three modulation modes such as BPSK, QPSK, 16QAM, etc., using d...

AI Technical Summary

Problems solved by technology

[0008] figure 1 The low-voltage power line broadband carrier communication system uses the existing power line as the transmission medium. Although it can be implemented as a communication line, there are many challenges in actual engineering use.

[0009] First: Power line construction is mainly used for power transmission. In the process of power construction, communication needs are not fully considered, resulting in the use of power lines for transmission. For example, due to changes in electrical equipment on power lines, capacitance and resistance on power lines And the power branch also changes in real time, resulting in unpredictable coupling of the signal sent by the communication module to the power line signal, which cannot be described by accurate signal processing algorithms

[0010] Second: Many electrical equipment on the power line, such as switching power supply and motor equipment, will generate strong pulse interference on the power line during startup and use, and these pulses will fall into the communication frequency band, affecting communication performance

[0012] In the current development of power line communication products, we will first study the power line interference, analyze the characteristics of the interference, and determine specific algorithms for these interference characteristics, but this processing method has poor robustness

During use, if a new type of electrical equipment is added, and the application scenarios vary greatly, the performance of the product will vary greatly

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