inevitably come into conflict with existing TV services and also require good quality coax cable in the network. By using the lower frequency range up to 200 MHz, EoC G.hn technology is very robust and copes well with older cable networks, where higher attenuation levels can occur and also means there is less potential for conflict with any existing services. FM frequencies will require “notching” out in the G.hn band which would as explained reduce bandwidth, however FM is much less of a concern, as it is likely to cease in the very near future and most, if not all, FM Radio Services are now available on DAB or available to Stream. The MoCA 2.5 (Multimedia over Coax Alliance D-Band) system in particular uses the upper frequency range above 1,000 MHz so often the existing components in a CATV/MATV Network would need to be replaced, as they are usually only designed up to a frequency of 862 or sometimes 1,000 MHz. Like MoCA, DOCSIS 3.0 also requires far greater bandwidth to deliver a performance level equivalent to EoC and will struggle to meet the same performance levels on older cable Networks. (Figure 1)
dynamically distributed between download and upload. This means that G.hn throughput can be anywhere between:
800 / 800 Mbps 1,000 / 600 Mbps 600 / 1,000 Mbps
It is often possible to isolate or notch out specific frequencies i.e. the FM band from 88 – 108 MHz. This would result in a 10% bandwidth loss (200 MHz – 20 MHz) resulting in a combined bandwidth for up/downstream of 1,440 Mbps. Or it is possible to limit the frequency used to 0-100 MHz resulting in 50% bandwidth loss leaving 800 Mbps of bandwidth. Commonly, tap and splitter frequencies start at 5 MHz – resulting in around a 2.5% loss of G.hn bandwidth but tests have shown that it is still possible to maintain link speeds in excess of 1,500 Mbps. Comparative Technologies EoC G.hn Wave 2 Technology additionally provides significant advantages over other, similar comparative technologies. The two main comparative technologies are MoCA and DOCSIS. MoCA and DOCSIS both use the frequency range above 470 MHz, so
Figure 1
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CAI Feedback Spring 2024
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