Link-Adaptive Physical Layer for Indoor Broadband Power-Line Communications

Increasing interest in smart home automation systems or home networks has driven the use of low-voltage power lines as a high-speed data channel. Since this type of power line is not designed for communication purposes, the channel exhibits unfavorable transmission properties. In this paper, a novel orthogonal frequency-division multiplexing-based physical-layer architecture for indoor broadband power-line communications is proposed. For the design of the layer, a new constellation for bit-mapping (or modulation) is introduced to increase the transmission rate over a sudden phase-shift-prone channel. In addition, a simple bit-loading scheme is adopted and a new preamble for a packet-based power-line communication system is proposed. The proposed layer is implemented as a type of testbed, and is field-tested in labs and in residential homes. The test results demonstrate that the proposed system has good channel adaptivity and achieves high transmission rates.