Huawei and Qualcomm have demonstrated mobile TV interoperability between a handset and an existing UMTS cellular base station, using the 3GPP multicasting standard MBMS. The system will almost certainly go live in Hong Kong at PCCW later this year.
So far only IP Wireless has targeted MBMS mobile TV delivery using one way, unpaired TDD spectrum that has been granted as part of most European and Asian 3G licenses. Huawei is the first base station maker to go to the trouble to test MBMS publicly and says that this combination requires no hardware change to the handset whatsoever, just a software upgrade.
MBMS builds on the Cell Multimedia Broadcast system that was thought of by most as insufficient to carry video across a 3G network, but in May last year PCCW in Hong Kong launched a service there which carried a handful of channels as a free to air broadcasts, used to tempt customers across to its 3G services. Now the new Huawei base station software release has been shown working with the Qualcomm MSM7200 Mobile Station Modem chipset that was launched for use with use with HSDPA networks. It looks like Qualcomm quietly added support for multicasting.
During the interoperability test, video streamed smoothly at 256 Kbps per TV channel and the systems is said to be capable of handling more than 12 TV channels in what it describes as a single radio channel. Given that 12 channels at 256 Kbps would take up at least 3 Mbps we presume that this is a 5 MHz channel, the same as the one that IP Wireless works in, and which has been allocated as unpaired to most operators.
Huawei said that MBMS allowed streaming to be suspended during an incoming voice call and automatically resumed streaming when the call ended and that the successful test means that MBMS is on track for large-scale commercial deployments in 2007.
It was Huawei that demonstrated TV on the Cell Multimedia Broadcast system in October 2005, and got the service running for PCCW in May. PCCW, known for the largest commercial installation of fixed line IPTV in the world, began to offer TV programming from its Now TV IPTV service, to its 110,000 3G phone users. Now TV has over 550,000 fixed line IPTV customers and this is the closest we have come to a true, integrated quadruple play.
With a software upgrade to both base station and handsets, this compares exceptionally well with the costs of launching a MediaFLO or DVB-H service, which requires a network of extra transmitters, costing up to $500 million for a large country. Although these datacasting networks may become necessary in time, multicasting from existing base stations can give cellular operators their own TV services, without wastefully using up precious mobile voice spectrum, allowing them to make the immediate switch out of unicasting.
It also means that a cellular operator will be able to allow broadcasters to take the weight of mobile TV datacast expenditure in building new networks, and yet still have their own TV resource that can differentiate cellco services, even if each of them in a given territory partners with the same TV operation for DVB-H, T-DMb or MediaFLO services.
Many cellcos have been worried that the agenda in mobile TV was too easily controlled by broadcasters which have a head start with central transmitter stations and vast antennas. The ideal solution is if MBMS can bring the kind of Quarter VGA screen resolution that DVB-H can bring.
The way MBMS works is that operators use the bandwidth for a TV channel only once per base station, no matter how many people view a particular TV channel, instead of sending a separate stream to each customer on the network, as it does in unicasting.
Uncompressed QVGA runs at 92 Mbps, but with modern codecs used for compression, it can be certainly be brought down to under 400 Kbps, including sound, and without too much loss of quality it can reach 256 kbps, certainly if it is statistically multiplexed in parallel streams with other channels.
MBMS can work both as a permanently on broadcasting system which can use statistical multiplexing to make the channels even more dense, or it can be use as a multicast services where no TV channel is broadcast by a base station until it is requested by a handset user. MBMS can also support file downloads in background to handsets, so clipcasts and other multimedia applications can be delivered by it.
By using multicasting cellcos can begin developing their own advertising revenue streams, something that datacast services run by broadcasters was likely to deny them. Also the spectrum required already exists, so there is now slow and costly wait for UHF spectrum to become available as there is with DVB-H.
The main difference for mobile TV using multicasting is that customers need a handset to receive it, whereas DVB-H, MediaFLO and others can be picked up on cheap non-handset devices just as easily. That’s because the unpaired spectrum is in the same spectrum range as the cellular signal, so it’s picked up by the same complex handset radio. Cellcos prefer this because it limits the services to cellular customers, while broadcasters prefer as wide a set of delivery options as possible, to prevent being held in thrall by cellular operators.
Yu Chengdong, president of Huawei Wireless Network Product Line, said: ‘MBMS service will be widely adopted by operators this year, with more and more equipment and terminal suppliers supporting MBMS service.’
Luis Pineda, senior vice president of marketing and product management for Qualcomm CDMA Technologies, commented: “Qualcomm’s successful testing with Huawei is a significant milestone in the commercialization of MBMS technology, which gives network operators the ability to offer real-time infotainment to wireless users over their UMTS networks. We remain committed to working closely with the entire wireless industry in bringing new mobile capabilities to market around the world.”
Already in Japan the CDMA equivalent of MBMS, BCMCS, is under trial with KDDI, which is also currently trialling MediaFLO as well as providing handsets that can receive the native Japanese ISDB-T hybrid Terrestrial TV – mobile TV hybrid.
At 3GSM in a few weeks, a cluster of European based international operators including Vodafone, Orange and Telefonica, are expected to announce an acceleration of their mobile TV initiatives using MBMS. So far a single trial has been held with the technology, between the three companies in Bristol in the UK, working alongside 3 Group. Over 15 TV stations were proven to work with the IP Wireless TDtv technology using MBMS, and the service appears ready to go to its next stage which is a commercial trial or full scale deployment somewhere in Europe.
But even this will be challenged if the technology at the base station costs no extra except a software upgrade, especially if the handset itself is also a software upgrade. The IP Wireless system requires a $10,000 card installed at the base station and $20 worth of chips for each handset, plus it needs to attract handset makers to the multicast approach to mobile TV.
If this becomes a series of software upgrades then all resistance from cellular operators will evaporate leaving it a ‘no brainer’ to add multicast mobile TV for a cellco, regardless of whether or not it has already joined a DVB-H or other datacast TV initiative.
Huawei, being Chinese itself, would be ideally placed to carry the struggle between cellcos and broadcasters over mobile TV into China, where the broadcasting regulator SARFT has insisted on developing a home grown new technology for datacasting, and where the cellular operators are rushing to have something in place in time for the 2008 Summer Olympics. This service is unlikely to be in place in time for the Olympics and China may seek alternatives that it can rapidly put in place.
If the signal is not sent from a broadcast transmitter, there would be an argument that SARFT is not the relevant regulator and then the large Chinese cellcos could meet the deadline in plenty of time by using MBMS.