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Accounting for MPEG2/4, legacy standards, etc.
How are factors such as MPEG2/4, legacy standards, bandwidth, etc., taken into account? Reeder said that today's deployments are typically well controlled, with known servers delivering specific content using known standards over fast, local IP networks. In some respects, the early rollouts are comparable to cable deployments, although these are more cost effective and with more opportunities in the longer term. "Bandwidth is the main issue, but that is relatively cheap to upgrade, especially when considering the revenue opportunities for service on top," he noted.
Rajan said: "There are some MPEG2 trials, and deployments are likely to be in MPEG4 (H.264), which will enable more consumers to be reached over existing connections. As our current product development efforts are focused on low-cost, value-engineered products for MPEG4, we expect to enable mass-market MPEG4 deployment in the same way that we enabled mass-market deployment for MPEG2."
Kejriwal said that content services pay a huge price in terms of network bandwidth. A few subscribers downloading high-bandwidth streaming video can absorb much of the available bandwidth in a cell, increasing the likelihood of interrupted voice service. So, bandwidth is certainly a limitation and there have been some steps for overcoming this, including: Lowering bandwidth before transmission by encoding video signals into MPEG1, 2 and 4 formats multicasting, which enables the delivery of multiple services to multiple devices, thereby improving distribution interactivity and presentation of the media. "In addition, the quality of streaming video over the cellular network is disappointing, because the transmission rates-one to 15 frames per second-are much slower than the 25 to 30 frames/second to which TV viewers are accustomed to. All of these are being taken into account, and in fact, much R&D surrounds these issues to help technology evolve in much sophisticated manner so that a perfect business case is delivered for all in the industry."
Kanjilal added that MPEG2 is the standard used for audio/video coding in traditional digital TV. For TV-like experience on a handheld device with smaller screen, the next-generation MPEG standard (MPEG4-AVC) is an optimal selection. He said: "Bandwidth depends on what modulation scheme is used.
The number of channels that can fit into the overall bandwidth is determined by what content is being transmitted. For example, a news channel may require a lower bandwidth as compared to a sports channel. Legacy standards are not taken into account, as this is a new standard. Based on the existing DVB-T standard, DVB-T receivers are unable to receive DVB-H signals and vice-versa, due to the unique properties of DVB-H that allow mobility, indoor coverage and operation on small screen devices with low power consumption requirements.
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