A low-voltage power line carrier communication anti-jamming system

Abstract

The invention discloses an anti-jamming system for low-voltage power line carrier communication, which includes a transmitting end spread signal spectrum module and a receiving end connection expansion restoration module, the transmitting end spread signal spectrum module is connected to the channel through a first intelligent interface circuit, and the receiving end The termination expansion and recovery module is connected to the channel through the second intelligent interface circuit. The present invention spreads the information to be transmitted to a wider frequency band with a pseudo-random code (convolutional code) through direct spread spectrum (DSSS) in exchange for higher communication reliability. At the same time, the same convolutional code is used at the receiving end to despread the received signal. Since there is no correlation between the interference signal and the convolutional code in this process, the power of the interference signal that is extended at the receiving end and falls into the signal frequency band is greatly reduced. Through this method of the present invention, the power of the interference signal can be greatly improved. The signal-to-noise ratio of the output, so as to achieve the purpose of anti-interference.

Description

technical field [0001] The present invention relates to the technical field of power line carrier communication, and more specifically relates to an anti-interference system for low voltage power line carrier communication. Background technique [0002] Low-voltage power line carrier communication (PLC) is a communication method that uses low-voltage power lines to transmit information. It is a communication technology that uses existing low-voltage power lines to transmit signals at high speed through carrier waves. The advantage of PLC is that the low-voltage power line distribution network is widely distributed, easy to access, and multi-users can share broadband. However, in addition to PLC's own advantages, environmental factors such as time-varying channel impedance, uncertain noise interference, and strong signal attenuation determine that PLC still has many problems. According to different noise sources, the noise is mainly divided into: colored background noise, na...

AI Technical Summary

Problems solved by technology

The first three types of noise have weak time-varying properties, and are generally attributed to background noise. The background noise is discrete Gaussian, and it is a noise that always exists on the channel. The main interference on the low-voltage power line channel is the background noise, which seriously affects the power line carrier. communication success rate

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