電力線搬送(電力線通信, 電灯線通信)通信メモ/Note of Power Line Communications (PLCs)
( modified at 2015年10月11日 )
2014
2012
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<!--[if !supportLists]-->General Emission Limits. Consistent with our stated intention to proceed cautiously in authorizing BPL systems, we proposed in the Notice to continue to apply the existing radiated emission limits for carrier current systems used as unintentional radiators, as set forth in Section 15.109(e) of the rules, to Access BPL systems. (注:In-house BPLについての記述はない)
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総務省研究会、離隔距離(30m点)と10m点の電磁波減衰特性L 2−10MHz:18dB 10−30MHz:14dB | |
30uv/m= 29.5 dBuV/m @30m | 2−10MHz:29.5+18=47.5dBuV/m
@10m 10−30MHz:29.5+14=43.5dBuV/m @10m |
1) <!--[endif]--> Distance corrections are to be made in accordance with Section 15.31(f) of the Rules.
microvolts/metar @30m |
microvolts/meter @3m | |
1.705M - 30MHz |
30 (=29.5dBμV/m) | (=69.5dBμV/m: extrapolated using the factor 40dB/dec) |
30M - 88MHz |
100 (=40dBμV/m) |
E=sqrt(30P)/R [V/m]
ただし、Pはアンテナに供給された電力([W], この場合は、10dBm)、R=30m. 値を代入すると、E= 85.2 [dBマイクロV/m]。(cf. アンテナハンドブック、ISBN4-7898-1025-9, p.281)
=sqrt(30 *-40dBi * -60dBm/Hz*(13.41MHz-13.36MHz)) / 30m
ただし、電力線をアンテナとして見た場合の利得は、<-40dBi。
OFDM送信機出力:-60dBm/Hz (室内Parsonal Area Networkを想定)。
=12.9μV/m [@13MHz band]
Therefore the received power by a radio astronomy antenna with the gain of 0 dBi is given as,
Pr = E - 20log f ・- 167.2
= [20 log10(12.9) - 10] -20 log10 (13.385 /1000) ・- 167.2
ただし、建物の壁によるシールド効果を10dB と仮定 (CISPR準拠)
=-117.5 dBW [@13MHz band]
The free-space propagation loss between isotropic antennas, Lbf (dB), is given as follows:
Lbf = 32.4 + 20 log f + 20 log d , where f is the frequency in MHz, and d is the distance between the RAS antenna and the PLC system in km.
Lbf = 32.4 + 20 log10(13.385) + 20 log10( d ) .......(eq.4)
Lbf = -117.5 - (-185) = 67.5 (dB) .........(eq.5)
32.4 + 20 log10(13.385) + 20 log10( d ) = 67.5 であるから、
d= 4.25 km (なお、参考文献の仮定では、424km)
- extrapolate x [dBmV/m (at 3m)] from y [mV/m (at 30m)]
- x= 20*LOG10(y)+20
freq. |
y [mV/m (at 30m)] |
x [dBmV/m (at 3m)] |
1.705M-10M |
100 |
60 |
10M-13.553M,13.567M-26.96M, 27.28M-30M |
30 |
49.54243 |
13.553M-13.567M, 26.96M-27.28M |
10,000 |
100 |
Frequency (MHz) |
Field strength (uV/m) |
Measurement dis-tance (meters) |
電界強度が距離の2 乗に反比例すると仮定して、測定距離3m に換算 (cf. 電力線搬送通信設備に関する研究会報告書, 47CFR15.31(f)(2) ) 69.5dBmV/m |
1.705‐30.0 | 30(uV/m)=29.5dBuV/m |
30 | |
30-88 | 100 uV/m =40dBuV/m |
3 |
(注)CISPR22には規定はないが、通信ポートの伝導妨害波許容値を規定する際の根拠値を使用
ClassB, Quasi-Peak CISPR Pub.22 FCC微弱無線 30MHz以下(注) 30M-230MHz 1.705 - 30MHz 30-88MHz@3m 54.0dBuV/m (変換値: 40.5dBμV/m =[30+20(1-log10(3))], 20 dB/decade を使用) (変換値 69.5dBuV/m, 40dB/dec を使用) 40dBμV/m @10m 都会、市街地、田園地方のいずれの場合も、35dBμV/m 30 dBμ V/m(変換値 48.6dBuV/m, 40dB/dec を使用) (変換値: 29.5dBμV/m@10m(20 dB/decade)を使用) @30m --29.5dBuV/m 距離換算の方法 (FCC 47CFR15.31(f))
(1) At frequencies at or above 30 MHz,
When performing measurements at a distance other than that specified, the results shall be extrapolated to the specified distance using an extrapolation actor of 20 dB/decade (inverse linear-distance for field strength measurements; inverse-linear-distance-squared for power density measurements).(2) At frequencies below 30 MHz,when performing measurements at a closer distance than specified, the results shall be extrapolated to the specified distance by either making easurements at a minimum of two distances on at least one radial to determine the proper extrapolation factor or by using the square of an inverse linear distance extrapolation factor (40 dB/decade).
322MHz以下:毎メートル500μV (=20log500=54dBμV/m)CISPR Pub.22 classB:
30M-230MHz:40.5dBμV/m@10m=[40.5+20(1-log3)=] 51dBμV/m@3m
MPHPT (the Ministry of Public Management, Home Affairs, Posts and Telecommunications, Japan )RADIO LAW (PDF)電波法関係(微弱無線局、高周波利用設備、電力線搬送、誘導式無線)
cf. The Ministry of Posts and Telecommunications, Final Report of the Study Group for Power Line Communications, July 1986.
日本国周波数分配表 [表] | Frequency Allocation Table of Japan
Phase Coupling
for Power Line Communications
* phase
coupling loss
* Evaluating
Power Line Environments Using the Echelon PLCA-22 Communication
Analyzer
characteristic impedance (Zo) of the wire
PSK modulation of Echelon PLT-21 is better than DS/SS mod. of PLT-10A ?
Japanese Activity
General References
OSGi (ホーム・ゲートウェイAPI 仕様策定)
MicroSoft: Home networking Simple Control Protocol (SCP)
情報処理学会、第・/A>T9回(平成11年後・/A>) 全国大会, 特別・/A>Zッション〔4B・/A>・黶l (9月30・/A>( 木)9:00〜11:00),情報家・ /A>d とホー・/A>ネットワーク、情報家電用ソフトウェア, ・ /A> タ長 小川 克彦(NTT), 岩手県立大学
CSMA/CA
Medium Access Control of Wireless LANs for Mobile Computing, Kwang-Cheng Chen
IEEE802.11a and ETSI Hiperlan-II committees have drafted standards for broadband multimedia indoor communication in the 5 GHz band based on orthogonal frequency division multiplex ( OFDM) communication.
Amitava Dutta-Roy, ``Networks for Homes,''IEEE Spectrum, December, 1999, Volume 36,Number 12
網電 Networked Appliances ・/A>、究会