Broadband sharing using power grids in multiple-dwelling units

Communication channel capacity for the residential power lines within multiple-dwelling units (MDU´s) is evaluated to check for the potential use of power grid in shared broadband access. Several measurements of noise and attenuation in the HomePlug band (2 MHz-30 MHz) on actual MDU power grids are measured. Two different grid topologies are considered: Star and bus, which are the foremost grid topologies of buildings in urban, suburban and rural areas. Both in-phase and across-phase performance are measured. The individual effect of electricity meters inherently present across flat-to-flat path is also evaluated. An MDU emulator has been built using meters only to measure the end-to-end frequency response of different meter types without cables. Finally, the obtained results are used to calculate the theoretical channel capacity for the different configurations of MDU grid with and without the effect of meters. The capacity of power line at all test locations selected is found far above the targeted data rates for broadband distribution and sharing. Capacity in the range of 300-400 Mbps is common in MDU´s with 2-3 floors span between transmitting and receiving nodes, which implies a total span of 5-6 floors when selecting the position of internet gateway carefully. It is also proved that the decrease in link capacity due to the existence of 2 electricity meters in between sender and receiver has an average value of 14 %, while the effect of normal cable distance within home could reduce link capacity by more than 35%.