G.hn Silicon Emerges from Vaporware Territory
by Ganesh T S on February 2, 2011 3:33 PM EST- Posted in
- Powerline Adapters
- G.hn
- HomePlug
Powerline networking products are quite popular in the European and Asian markets compared to the US. The Western Digital Livewire product was the first powerline product reviewed by AnandTech. In that piece, I had covered the various powerline networking standards currently in existence. The initiatives of the HomePlug consortium resulted in the IEEE P1901 standard and HomeGrid's efforts have led to the ITU G.hn specifications.
In the WD Livewire coverage, I had noted the lack of working silicon from any of the G.hn supporters as the prime reason for its struggles.
Over the last few years, many of the small powerline communication companies have ended up getting acquired by bigger corporations. Intellon was the pioneer of the HomePlug initiative, and Atheros bought them in December 2009 to augment their networking product portfolio. The powerline networking division of Conexant was purchased by CopperGate, who themselves were bought by Sigma Designs in October 2009. Gigle Networks was taken over by Broadcom, while DS2 found itself in Marvell's hands. ST Microlectronics has agreed to take over Arkados, and the only remaining player of note seems to be Spidcom. The powerline networking market is too small to support a lot of players, and it makes sense to bundle the technology with other networking offerings.
Atheros got hold of Intellon to create a hybrid networking platform. This is evidenced by the combo reference design (wi-fi router + powerline adapter) which has been adopted by Netgear and D-Link. Their future outlook involves the IEEE P1905 which is the convergent digital home network working group.
Sigma Designs is a more interesting story. IPTV has been at the core of Sigma Designs. Sigma created a vision with the set top box as the hub to power the new digital home. They acquired Coppergate to shore up the powerline networking side and Z-Wave technology for wireless home control transceivers.
Broadcom, Marvell and ST probably plan to use their PLC purchases to act as a one-stop-shop for their networking gear customers.
While Atheros is categorical in putting its weight behind IEEE P1901, the lineup from Sigma Designs is more interesting. When I visited Sigma Designs in October, I was shown some working demonstrations of HomePlug silicon, while G.hn silicon was shown at CES 2011. We will discuss Sigma's lineup first.
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wolrah - Thursday, February 3, 2011 - link
Sorry bud, but you're completely wrong. Look up the G.hn specs yourself. Depending on the region, on power lines it'll use anywhere from 1-200MHz. The power lines in your house are in general unshielded, making them effectively an enormous (though not particularly well optimized of course) antenna. The frequencies in use overlap with numerous radio bands, including a number of amateur bands, CB, commercial AM/FM, and commercial/government SW/MW/LW. I don't believe most public safety spectrum at least here in the US is that low down, but there probably is some. Particularly in amateur HF and SW/MW/LW being able to receive weak distant signals is important, so any interference on those bands is an annoyance to area users.I'm not sure why you bring up cordless phones. BPL and power-line networking don't come anywhere close to those, so there's no reason to think it passing the "teenage girl test" means anything at all (900MHz, 1.8GHz, 2.4GHz, and 5.8GHz are the four cordless phone frequencies seen in the US).
Again it will not interfere with any unlicensed radio services I'm aware of other than CB, but you're putting a fat signal in to a huge antenna right in the middle of a lot of licensed spectrum. The area of effect isn't huge, but as an amateur operator if you were my neighbor and you were broadcasting anything on the HF bands I'd offer to help fix it if possible, but if it couldn't be told to not operate in certain ranges it's turning off or you're getting an FCC complaint for broadcasting without a license and interfering with licensed users.
derkurt - Sunday, February 6, 2011 - link
I don't know exactly about the new G.hn devices, but a HomePlug AV2 500 Mbit/s device uses a spectrum from 2-68 Mhz. The standard employs these frequency filters (source: German wikipedia):* f ≤ 1,71 – AM Broadcast and below
* 1,71 < f < 1,8 – between AM and 160 meters band
* 1,8 ≤ f ≤ 2,0 – 160 meters amateur band
* 3,5 ≤ f ≤ 4,0 – 80 meters amateur band
* 5,33 ≤ f ≤ 5,407 – 5 MHz amateur band
* 7,0 ≤ f ≤ 7,3 – 40 meters amateur band
* 10,10 ≤ f ≤ 10,15 – 30 meters amateur band
* 14,0 ≤ f ≤ 14,35 – 20 meter amateur band
* 18,068 ≤ f ≤ 18,168 – 17 meter amateur band
* 21,0 ≤ f ≤ 21,45 – 15 meter amateur band
* 24,89 ≤ f ≤ 24,99 – 12 meter amateur band
* f >= 28,0 – 10 meter amateur band
In Germany, you are allowed to use Powerline devices as long as they don't interfere with other HF applications in your neighborhood. If they do, the Bundesnetzagentur (German FCC) can be called, which may request removal of the source of interference.
So far, I haven't heard of a single case where a radio amateur successfully requested removal of a HomePlug device. Keep in mind that the amateurs are likely to be the only ones which might be disturbed by PLC at 2-68 Mhz. In fact, as far as I know, the filters mentioned above cover all frequencies where a radio amateur is legally allowed to operate within the 2-68 Mhz range. Also, although PLC is admittedly turning the power wiring into an antenna, the signal strength remains small compared to other in-house HF applications, such as Wi-Fi.
In theory, PLC is a "dirty" solution and looks like it would be bound to cause problems. In reality, devices such as mobile phones, babyphones (which also use the power lines), and even WLAN are far more likely to annoy your neighbor.
davmat787 - Sunday, February 6, 2011 - link
Excellent post sir. Just the kind of complete and detailed post one would expect from a German. :)HoosierEngineer5 - Thursday, February 3, 2011 - link
Do any of these technologies replace the X-10 modules, or are they simply replicate Ethernet? It would be great if these could actually DO something other than pass data...andrewmc - Thursday, February 3, 2011 - link
Very nice. So when do I get my Homeplug Green PHY silicon.aahjnnot - Friday, February 4, 2011 - link
Powerline networking is relatively successful in Europe and Asia compared with North America because our housing stock is very different from yours. WiFi isn't a good solution in areas of very dense population, as interference from neighbouring networks can kill throughput. Traditional European housing stock with thick internal walls made of brick or stone kills WiFi, and the long, narrow shape of traditional British terraces mean that Wifi users can often have several neighouring networks that are closer than their own access point. And retro-fitting Ethernet into a property with traditionally plastered walls, stone floors and no wall voids needs either visible cabling or significant redecoration.By contrast, the traditional American wood-built detached property sitting in its own spacious yard is perfect for WiFi.
ragincajun84 - Wednesday, February 9, 2011 - link
Is this a paid article? It reads like an ad for Sigma and G.hn. It barely mentions the other silicon players yet raves about Sigma demos and slideware. Sigma has not brought a single powerline product to market and G.hn has been hyped for 5 years and still has no products on the market.ganeshts - Thursday, February 10, 2011 - link
I believe I have pointed out enough places where G.hn is yet to catch up or will have potential problems.I wrote the article after seeing Sigma's demonstrations both at their HQ in CA as well as their demo at CES. It really works in the demo situation / lab. Any new company will have teething trouble, trying to get into the market and convince customers. That doesn't mean the technology is not good. Yes, G.hn will have to present a really valid case to the concerned people to shift from HomePlug because HomePlug is very well established and mature.
At CES, after seeing what Atheros and Sigma had to offer, I believe Sigma has taken bigger strides and that is why 75% of the article is focused on them. (They have taken bigger strides because G.hn hasn't seen mature silicon yet). This article wasn't meant to be a coverage of the PLC industry as a whole.