Shanghai Telecom has started deploying optical gateways from Chinese firm FiberHome, which include wireless networking chips from Celeno Communications, to enable the rollout of wireless in-home distribution of high-definition IPTV services.

Shanghai Telecom selected the optical gateways, based on Celeno's CL1800 high-performance Wi-Fi system-on-a-chip (SoC), as part of its rollout of Fibre-to-the-Home (FTTH) connections across the city of Shangha. 

The telco's FTTH project, which was officially launched in June of last year, forms part of a much larger fibre initiative by China Telecom, which will launch FTTH projects in other provinces shortly.

We spoke to Lior Weiss, Vice-President of Marketing at Celeno Communications, to find out more details about the deployment in Shanghai:

What is the current footprint of Shanghai Telecom's FTTH network?

LW: Shanghai Telecom have launched the new fast broadband service branded "City Lights Network" (which is part of China Telecom's strategy for national development) based on the new ePON GW in April of 2010.

The service was launched with a 10 Mbps package, and 30, 50,100Mbps offerings will be turned on shortly. The service provider' plan is to serve 3mn homes with this service by 2012 (by the end of 2009, 750K households had already FTTH access).

Rollout of the new Fiberhome ePON Gateway has just started and we are expecting a fast ramp up by Shanghai Telecom to reach their ambitious 3mn households goal in 2012.  Every Fiberhome Gateway includes a Celeno Wi-Fi chip and respectively every set top box is attached to another Celeno based Wi-Fi adapter client. So we are looking at 2-4 chips per household.

Why was wireless distribution selected for the in-home streaming of IPTV services by Shanghai Telecom?

Shanghai Telecom made it quite clear during their service launch of "City Lights Network" a few months ago that wireless home networking is quite important for them in order to support the evolving digital life style and the needs of Chinese families by firstly making minimum interruptions to the subscribers during installations, which means supporting self-installation techniques as much as possible (and avoiding the need for new wiring and cabling in the home).

Wireless home networking is also important to them as it can support new evolving multimedia consumption habits on portable devices and in home-locations, where media was not typically consumed in the past, such as the kitchen. That includes delivering IPTV paid-content beyond the STB to portable devices as well as free OTT and walled-garden internet-based content.

I think they found Wi-Fi quite satisfactory from that stand point. Wiring with CAT-5 is of course out of the question. Some alternative wired based techniques such as power line or MoCA are either unreliable or require some technician set up time and at the end of the day it cannot support conveniently portable devices.

What were the main criteria FiberHome applied when selecting SoC solutions from Celeno for this deployment?

Actually we were surprised how rigorous testing China Telecom Laboratories and Shanghai Telecom R&D put us through. Apparently the Shanghai Telecom IPTV project is one of the most challenging for Wi-Fi technology we have encountered so far, for a few reasons.  Firstly, it is a very bandwidth hungry installation with optical access - so multiple HD set-top boxes are the norm in a Shanghai Telecom's consumer home. That means a lot of Wi-Fi capacity is required.  

Secondly, Chinese homes pose an extremely tough environment for Wi-Fi propagation - typically, interior walls in Shanghai are made of concrete and eight to ten inches (20 cm to 25 cm) thick. This is probably due to the rapid growth of the city and the industrialised high-riser's build up techniques. It was not uncommon to see a laptop which could not even connect with an off the shelf 2.4 GHz router located in the next room. In contrast, the service provider requires full-home coverage for its 5GHz IPTV over Wi-Fi deployment!

Thirdly, Chinese regulations are such that the 5 GHz unlicensed Wi-Fi spectrum is limited to only to a small portion, relative to the US or European spectrum. In China they are allowed to use only 5 radio channels compared with 20, as in the US and Europe. That means that the probability of interference from neighbouring apartments increases, and interference immunity techniques are more important.

Because of these tough conditions, China Telecom and Shanghai Telecom put the Wi-Fi contenders through endless test beds, evaluating not only long distance reach but also testing the coverage in vertical penetration through multiple floors in town houses, how the chips distribute traffic to multiple clients while maintaining QoS, and how the chips behave in the presence of interference from a neighbouring Wi-Fi system.

The Celeno OptimizAIR technology excelled in those tests. Our digital transmit beam forming and antenna diversity helped deliver the video with greater coverage and very robustly in between rooms and throughout floors and ceilings, Our TDM scheduler maintained carrier-grade delivery with zero packet error rate to each one of the set top boxes and our silicone-based interference detection and fast channel hopping mechanism produced seamless channel switching in the interference tests.