RESULTS OF INTERFERENCE CALCULATIONS

RESULTS OF INTERFERENCE CALCULATIONS

1. Land-Mobile Service

Calculations of close-to-the-line interference potential for vehicular land-mobile receivers due to a BPL transmitter operating at FCC Part 15 limits show that there would be significant increases in the noise floor due to interference. As can be seen in

Table 6-3, for frequencies less than 30 MHz, virtually all points close to the line would experience (I+N)/N levels greater than 10 dB. In other words, there would be at least a ten-fold increase in total receiver noise power on the street adjacent to the BPL device and power lines. At 40 MHz, a majority of the areas in a road along the power line would see this level of interference.
Table 6-3: Percent of points exceeding specified interference level, by frequency, for land-mobile receiver system within 15 meters of a BPL-energized power line. Radiated power and noise are into a 2.8 kHz bandwidth for 4 MHz, 15 MHz and 25 MHz, and a 16 kHz bandwidth at 40 MHz.

The increases in the noise floor a land-mobile system might encounter along a BPL-energized power line are further illustrated in Figure 6-4. In this figure, (I+N)/N values are depicted using colors from red to blue, with dark red representing 50 dB and dark blue representing zero.