Modeling and performance analysis of PLC channels with external interference in outdoor and indoor environments

Aiming at to verify if the specifications of pre- established service quality parameters of commercial BPL technology agree with practical results this contribution presents and discusses some measurement carried out from medium- and low- voltages networks when commercial BPL are used to data transmission. In data transmissions using PLC (powerline communications) technology, network performance is influenced by interference generated by other equipment attached to the network, mostly equipment with electric motors, power converters, and reactors. Voltage drops in high frequency electric circuits, as a result of the use of metallic conductors and their characteristics, is another factor that causes attenuation in the signal modulated by PLC systems. These interference and attenuation directly dictate the signal/noise ratio, which is one of the factors that affect channel capacity. Another factor that affects the performance is the channel bandwidth; consequently, the channel´s capacity is dependent on the bandwidth. In this contribution, the bandwidth considered is the one from the commercial BPL technology that is around 28 MHz. Measurements obtained from the trials conducted at CELG, an utility company that operates in the Midwest region of Brazil, on low- and medium-voltage networks are used for comparison. Results have shown that in outdoor and indoor environments, the network throughput was about 3 Mbps, which did not coincide with the commercial BPL specifications.