As discussed in Part 1, power line communicaions (PLC) presents significant interference issues and technical problems. These problems became evident in various studies throughout Europe. Individual radiated-emissions measurement campaigns in 2000 and 2001 showed numerous inconsistencies, which are as follows: 1. University of Dortmund/Siemens, Germany. Tests using -2 dBm at 10 MHz result in just meeting NB 30 limits. 2. Sevilla, Spain. Tests show -40 to -50 dBm/Hz (0 to -10 dBm in 9 kHz BW) at d = 10 m (5-10 MHz) results in more than 20 dB above NB 30. These PLC systems require a minimum signal-to-noise ratio (SNR) of 15 dB. 3. Cologne, Germany. Measurements show +17 dBm total injected RF power, at 2-3 MHz, results in more than 13 dB above NB 30. 4. Suhr/AG, Switzerland. With -16 dBm, around 20 MHz results in 14 dB above NB 30. Outdoor cables are not so critical; 200-300 m in the street with one party at the end of the street being ASCOM connected. 5. Fulpmes/Stubai, Austria. Running an ASCOM system with typical specs: outdoor frequencies of 2.4, 4.8, and 8.4 MHz; indoor frequencies of 19.8 and 22.8 MHz; and PLC power levels of 17 dBm (50 mW, 124 dBμV, 90 dBμA) to -17 dBm (20μW, 90 dBμV, 56 dBμA.
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