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Experiments related to network issues. PLC Field trial in Arnhem The Netherlands 2. Radiating characteristics of L ow V oltage D istribution Networks. PLC Field trial in the city of Arnhem , NL. Start 2002, end May 2003 150 houses; 337 modems (included repeaters)
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Experiments related to network issues • PLC Field trial in Arnhem • The Netherlands • 2. Radiating characteristics of • Low Voltage Distribution • Networks
PLC Field trial in the city of Arnhem, NL • Start 2002, end May 2003 • 150 houses; • 337 modems (included repeaters) • 2 Mbit/s backbone via 6 medium voltage transformer stations. (35 users per transformer station) • Modem power density -50 dBm/Hz; • DSSS Technology
Operator results (Arnhem) • Users very satisfied with service, • Technology works, • Commercially not yet viable! • Practical 1,4 Mbit/s too slow for future, • Connecting 10 kV Transformers to infrastructure a logistic/economical problem, (40.000 Transformer stations to be connected).
Results measurements in Arnhem • Large variations in generated fields (30 to 40 dB) • Generated Fields: • Table A (JWG Questionnaire Option 2):pass • Table B (JWG Questionnaire Option 3) NB 30: fail • A few hundreds of meters from the PLC- area the generated fields are below ‘ITU rural’ noise level. • How many measurements are needed to assess the network compliance?
2. Additional measurement campaign Radiating characteristics of Low Voltage Distribution Networks LVDN’s
Radiating characteristics of LVDN’s • Voltage injection on mains wires (sym. and asym) • E and H–field measurements in and around 40 different houses: • Indoor: At 1 m and 3 m from injection point • Outdoor: At 3 m, 10 m, 100 m and 1000 m from building • ‘Antenna gain’ measurements of LVDN’s.
Results • Large variations in generated fields (>40 dB)because of large variations in mains geometry • The injection of voltages equal to the CISPR-22 class B mains voltage limits can result in magnetic field levels equal to the ‘table A’ field limits at 3 m distance. However, in most cases the generated fields will be lower than the ‘table A’ limits.
General conclusions • Local effects arise at locations in and around the PLC area. Further outside the PLC area fields will be lower than the existing noisefloor. BUT, the following phenomena is underestimated: • If in a large part of the world PLC networks are deployed with a large penetration rate, cumulative effects cause a rise in the noise floor in a large area (not near PLC systems!) (Applies << 50 MHz)
Conclusions Local PLC- effects are well known and can be controlled in some manner Near LVDN wires Near field ‘coupling’ In and around PLC-area Groundwave Above PLC-area Direct wave
Mondial PLC effects depend on deployment and penetration rate! Skywave Rise of noise floor Measured equivalent antenna gain (for sky wave) of LVDN’s in the frequency range 5 MHz- 20 MHz amounts on average -30 dBi.