run a computer simulation with our new power line model and found
that, under ideal conditions, the maximum achievable bit rate was
close to a gigabit per second per kilometer on an overhead medium
voltage unshielded U.S. electric power line that has been properly
conditioned through impedance matching. The gigabit can be shared by
a half dozen homes in a neighborhood to provide rates in the
hundreds of megabits per second range, much higher than DSL and even
Kavehrad adds, "If you condition those power lines
properly, they're an omni-present national treasure waiting to be
tapped for broadband Internet service delivery, especially in rural
areas where cable or DSL are unavailable."
say they are the first to evaluate data rate handling capacity for
overhead medium voltage unshielded U. S. electric power lines and
will outline their findings at the IEEE Consumer Communications
& Networking Conference in Las Vegas, Nev., Jan. 5. Their paper
is titled, "Transmission Channel Model and Capacity of Overhead
Multi-conductor Medium-Voltage Power-lines for Broadband
Communications." The authors are Pouyan Amirshahi, a doctoral
candidate in electrical engineering, and Kavehrad.
paper, the authors note that the junctions and branches in the U.S.
overhead electrical grid cause broadband signals to reflect and
produce multipath-like effects on these lines. This causes
degradation in power-line broadband transmission performance and
decreases transmission capacity.
Kavehrad explains, "The
signal can bounce back and forth in the lines if there is no proper
impedance matching. The bouncing takes energy away from the signal
and the loss is reflected in the ultimate capacity.
service, performance will depend on how close the power company
chooses to place the repeaters," he adds.
are continuing their studies. Kavehrad predicts that the engineering
issues to make BPL a technical alternative to DSL and cable will be
solved. Whether it will be an economical alternative remains to be
seen since there are interference issues that have to be overcome.
Source: Penn State