course, the notion of multicasting a single video or audio stream to
multiple devices sounds similar to the way TV and radio towers broadcast
their programming. How does LTE Broadcast differ from previous attempts
at mobile TV broadcast?
For example, LTE network can broadcast
“interactive video,” said Karam. Cellular operators can send the same
event, the same movie “on demand,” without killing their network.
Another pro for LTE Broadcast is that it is based on the eMBMS technology, standardized for LTE.
previous mobile TV broadcast efforts that required a host of new
handsets based on fragmented mobile TV broadcast technologies, eMBMS is
standardized. It’s a part of LTE Advanced.
previous mobile TV broadcasts that depended on a whole new network
infrastructure (everyone was racing to build more towers specific to
mobile TV broadcasting), LTE Broadcast uses the LTE radio
infrastructure. If an operator wants to get into the broadcast business,
the infrastructure is largely in place, although some upgrades to the
network core may be necessary.
Qualcomm is already on the record with its commitment to supporting eMBMS in their future radio chip.
competing with Qualcomm head to head,” said Karam. The company’s
technology, compliant with the Release 10 enhancements for eMBMS,
supports multiple concurrent sessions for multicast traffic along with
unicast traffic, on both TDD and FDD networks. It also provides support
for architectures combining LTE and Wi-Fi, and a standardized interface
to third-party eMBMS middleware. The Sequans chip, receiving eMBMS
packets, demodulates and de-packetize eMBMS signals and hands them off
to a video decoder.
The successful interoperability testing of
Alcatel-Lucent’s LTE infrastructure equipment is especially significant
to Sequans, as it “assures operators that the solution works end-to-end and is commercially viable,” said Karam.
The very idea of LTE
Broadcast isn’t just a “maybe-in-the-future” scenario. During the
International Consumer Electronics Show 2013, Verizon CEO Lowell McAdam
mentioned in his keynote that Verizon hoped to have the technology in
place to “broadcast” the biggest U.S. sporting event, the Super Bowl, in
2014. That technology is LTE Broadcast.
Sequans expects its
baseband chip -- built in 40-nm CMOS at Taiwan Semiconductor Manufacturing
Co. -- to be used in high-end handsets, USB dongles, customer premise
equipment and consumer electronic devices such as media tablets, gaming
and LTE-enabled cameras. Karam sees ample opportunity for its LTE-only
chip -- including the China Mobile’s TD-LTE market. Sequans last year
announced its partnership with Nationz Technologies Inc., China’s
leading supplier of RF chips. The companies have been working together
to develop dual-mode TD-SCDMA/LTE solutions.
Nationz and Primemobi, China’s leading cloud computing service provider,
both Sequans device partners in China, won significant portions of
China Mobile’s contract for the next large-scale trial of TD-LTE
technology in China, which started in the fourth quarter of 2012.
Ok. so this means, an additional receiver chip is not needed in the smartphone to receive TV signal, And can use the existing LTE modem with minor modifications. Right? If so that is an interesting proposition. This might have been a reason for DVBH/Mediaflo failure in addition to Internet streaming video.
Bolderdash. The only possible advantage LTE broadcast has over more efficient schemes, such as DVB-H or DVB-NGH, or even DVB-T2 tuned to work most effectively with mobile devives, is that the cell carriers can extract revenue for the LTE broadcasts. They cannot do so if cell users can bypass the carrier's cell network and go directly to the OTA broadcaster's network.
The carrier aggregation issue is an orthogonal discussion. It's useful to LTE, mainly because LTE requires such wide channels, and carriers don't often have slices that are 40 or 80 or more MHz wide. If you look at the numbers, though, you pay a price for LTE broadcast, compared with DVB-T2 for example, in spectral efficiency. In order to approach the spectral efficiency of DVB-T2, the LTE network needs to have very closely spaced towers. You pay price to transmit broadcast over a network designed for two-way unicast.
Those technical issues aside, mobile broadcast has always been a tough call. I guess that people on the go would much prefer to view content on demand than to have to conform to broadcast schedules. LTE will not change that. We've read this type of news item enough times now that I am quite skeptical. Just because something can be done does not mean that it should be done.
Let me be more specific about my disconnects here.
Carrier aggregation is important for a technology that requires cnannel huge channel widths, such as LTE does. It becomes much less important to ASTC or DVB-T2, which operate on 6 to 8 MHz channels. LTE as well as W-CDMA therefore provide carrier aggregation.
The comment about "on demand" video is certainly valid, but it's a non-sequitur. It is true that it takes a two-way network such as LTE to support VOD. You cannot do this with DVB-T or DVB-H. But then, this negates all that was said about the wonders of LTE broadcast. You do NOT "broadcast" VOD. By definition, what goes to an individual viewer only is not "broadcast." So using LTE in MBMS mode, for this type of VOD programming, is an egregious waste of spectrum!
Previous mobile TV efforts, such as DVB-H, were also based on standards. They failed anyway. So just because LTE MBMS is also a standard surely is no guarantor of success.
David Patterson, known for his pioneering research that led to RAID, clusters and more, is part of a team at UC Berkeley that recently made its RISC-V processor architecture an open source hardware offering. We talk with Patterson and one of his colleagues behind the effort about the opportunities they see, what new kinds of designs they hope to enable and what it means for today’s commercial processor giants such as Intel, ARM and Imagination Technologies.