Research And Design Of Power Line Communication With Encryption

Power line communication has the advantage richly endowed by nature wide application market.However,the traditional data transmission channel of power line communication is an open channel,the information will be easy to steal or tamper with by the third party in the process of information transmission.At the same time,there has been error problems with information transmission in the complex environment of power line channel,especially for encrypted data transmission error,it will produce the error avalanche effect at the decoding end so that seriously affects the effectiveness of information.So we combine the encryption communication and error correction coding technology combining to improve the safety and reliability of the communication system.In view of the domestic power line noise environment,the paper introduces the basic knowledge of power line channel characteristics and error correction coding techniques,then it studied the theory of power line carrier communication and the encryption and decryption code algorithm.Choose an encryption algorithm to apply to the system so as to meet the requirements of information security in the process of communication.Choose DES encryption and decryption algorithm to encrypt the data which ensures the security of data transmission process,it will increased difficulty to crack the stolen information.At the same time,in order to reduce the avalanche effect caused by the error of the encrypted data in the condition of error the communication,the system use(7,4)Hamming encoding technology with encrypted data in the channel encoding,increasing the anti-interference ability while the information is transferred in the complex and changeable channel of high transmission interference,reducing the overall bit error rate of the system.On the basis of the overall analysis of the system,the paper select TI’s high performance 32-bit fixed-point DSP chip TMS320F2812 for hardware as the core of the system,then the paper design the software part,software and communication protocol of the power line carrier communication encryption system,use CCS software programming to achieve the core algorithm of each main module of the power line carrier encryption communication system,including encryption coding and decoding module,error correction coding and decoding module and serial port transceiver module.Each module has independent function,in order to facilitate the main program calls.It couple and amplificate the single,modulate and demodulate the single through the corresponding peripheral circuit.The whole system has the characteristics of simple structure,flexible and so on.Finally,the paper test and analysis the low pressure PLC experimental setup.The designed encryption system of power line communication can communicate with others by proper encryption and decryption algorithm,the application of encryption and decryption algorithm improves the security of information.At the same time,it can be known by the contrast analysis of the error correction coding and the non-error correcting codes,the scheme of(7,4)Hamming error correction coding can effectively reduce bit error of the encrypted information so that improve the reliability of the system.