Project Number: FP6-IST-507554 Project Title: BROADBAND in ...

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FP6-IST-507554/JCP/R/Pub/D2.2-3.2
On the other hand strong radiation - or in other words the relatively high antenna gain - of a PLN impose strict
limitations on the power spectral density (PSD) of the broadband PLC transmitters in order to keep the
disturbing influences on radio services - operating in the same frequency band - within acceptable limits. As a
consequence, the signal to noise ratios at the PLC receivers are reduced, resulting in a relatively low spectral
efficiency (bit-rate per Hz).
In order to get an idea of the bit rate which can be transmitted over the outdoor (access) PLN, the maximum
capacity of typical powerline reference channels including realistic ingress noise and using acceptable PSD
masks have to be estimated. From 9 we take the results based on defined reference channel models, frequency
bands, transmit power spectral densities (PSD) and a noise scenario, taken from typical channel measurements.
Reference channel models
• RC1 Link as shown in Figure 8a), length L ≈ 100m without branches, only few reflection points
(attenuation ≈ 18 dB @ 10 MHz, relatively flat)
• RC2 Linear link as shown in Figure 8b) with 6 branching cables of similar lengths, similar
distances between branching points and total length L ≈ 110m (attenuation ≈ 40 dB @ 10 MHz,
notches)
• RC3 As RC2 but 8 branches and total length L ≈ 210m (attenuation ≈ 95dB @ 10 MHz, deep
notches)
• RC4 Power line access network with numerous branches, but without significant regular structure,
as typically found in residential areas (attenuation ≈ 100 dB @ 7.5 MHz, no deep notches)
7.2.1.2.2 Frequency bands
Figure 8: Reference topologies
• Band A: 0.5 to 20 MHz
• Band B: 0.5 to 10 MHz (above 10 MHz reserved for in-house PLC, ETSI PLT)
• Band C: C1 + C2 + C3
- C1: 1.6 to 3.5 MHz
- C2: 4.2 to 5.8 MHz
- C3: 7.4 to 9.4 MHz
(avoids the frequency bands of the main public and amateur radio services in Germany)
Frequency Band
Mbps A B C
RC1 453.7 242.9 146.4
RC2 272.7 164.2 98.7
RC3 92.3 92.0 55.5
RC4 45.4 45.4 26.9
Table 3: Theoretical channel Capacity (Transmit PSD = - 53 dB (V 2 /Hz)) 9
9 P. J. Langfeld, "The Capacity of typical Powerline Reference Channels and Strategies for System Design", Institute of Industrial
Information Systems, University of Karlsruhe, Germany