Data transmission method for domestic appliances using mains supply

摘要

The method involves using a number of transmitters (2), with an individual transmitter transmitting a message only if no other transmitter is operating. Each message includes an address field which defines the message destination with a verification field allowing the receiver to determine if the message is erroneous or not. The message is repeated a predetermined number of times, preferably three. The receiver considers the message only if that message was judged to be non-erroneous. Otherwise the receiver ignores the message. The carrier is frequency modulated by signals which are dual-phase coded in FSK. The time between messages to successive receivers is long compared to the duration of each message.