Patent ID: 7199706

Claim:
A digital intercom device, using power line communication (PLC), comprising: a power line interface for connection to a power line serving as a communication medium, wherein the interface communicates over the power line using Orthogonal Frequency Division Multiplexing (OFDM); an audio codec coupled to the power line interface for encoding and decoding digital data to and from data suitable for use by the power line interface; a digital to analog converter that receives digital decoded data from the codec and converts the digital coded data to a received analog signal; a receive audio amplifier that amplifies the received analog signal to a level adequate to drive a speaker; a transmit audio amplifier that amplifies a transmit audio signal and provides an amplified transmit audio signal as an output; an analog to digital converter that converts the amplified transmit audio signal to a digital representation thereof and passes the digital representation to the codec; a control processor that controls operation of the interface and the audio codec; and a switch interface receiving a signal from a push-to-talk switch, which causes the codec to encode the digital representation and the power line interface to place an OFDM modulated version of the digital representation onto the power line.