Home automation using power line communication is a unique idea of optimizing resource usage. Micro-controller generated signal is Frequency Shift keyed(modulated) and is sent on the power line through coupling circuitry and then demodulated and fed to the receiving end micro-controller and corresponding action is performed through relays and switches. Powerline communication is a progressing technology that utilizes electric power lines for efficient, instantaneous transmission of data. The objective of our project was to design and implement a power line communication network capable of controlling and monitoring multiple devices from a single node. Это и многое другое вы найдете в книге Home Automation Using Power Line Communication (karim shah,Zeshan Sikandar Niazi and M abdul Haq)