WiMAX technology could offer traditional broadcasters a cost-effective route to developing mobile TV services, write Filip Gluszak and David Richardson.
Despite the rise in popularity of user-generated videos and other "do-it-yourself" forms of content, when it comes to authentic revenue generation, broadcast television programming is still king.
The revenue it generates, regardless of whether it is distributed via ad-supported, free-to-air (FTA) broadcasting, pay television or any other model, dwarfs that of other content types.
Telcos and other communications service providers looking to leverage their IP-based networks to offer video as part of subscriber packages recognise the necessity and huge appeal this type of content has in winning and maintaining an audience share.
Similarly, mobile operators are finding that broadcast programming is the key to thriving in an increasingly competitive landscape. As growth rates from pure voice traffic flatten, they are introducing data applications, not the least of which are videos of popular broadcast network programmes.
Hence, mobile TV is already proving a promising ARPU generator for mobile operators, with several million subscribers to such services worldwide.
Beyond the ARPU increase, mobile distribution of broadcast programming offers such new business opportunities as targeted advertising models. It's not surprising that incumbent operators are investing in infrastructure to meet the consumer expectation for 'content anywhere, any time on any device'.
WiMAX is emerging as one of the most promising wireless networking technologies designed to meet this demand. However, broadcast-quality video is a bandwidth hog. As an IP-based network, WiMAX faces inherent scalability problems.
Each new customer requires more bandwidth, connectivity sessions grow longer and applications such as video require ever more capacity. Serving thousands of such individual 'unicast' streams becomes expensive, and there is a seemingly inevitable decline in quality of service at periods of peak demand.
One way to avoid these issues, and take full advantage of WiMAX to meet consumer demand and operator interests, is to implement hybrid broadcast/multicast architecture.
This type of architecture is economically feasible because TV viewers tend to aggregate around peak viewing times.
Despite the huge explosion in the amount of content now available on many networks and the inevitable fragmentation of audiences, not to mention the proliferation of FTA channels in the Middle East, the bulk of TV audiences are still largely served by 20 or so high-rating channels or networks across the region.
This is true of fixed TV viewing and is likely to be the same with mobile, with the channels or networks meeting the demand for appropriately produced programming directed at commuting periods and other times in the day or week when mobile viewing is likely to be popular.
A WiMAX TV broadcast/multicast solution enables operators to offer the most popular mobile programming at quality reception over predictable bandwidth and without any risk of congestion or contention during these peak-viewing periods.
In addition to nationwide or regional TV broadcasting, WiMAX TV also enables local content insertion and 'micro-broadcasting' - the efficient delivery of content within restricted areas during popular sports events or concerts, or within airports, campuses or hospitals.
While viewing habits do tend to aggregate around certain predictable times, and audiences tend to gravitate en masse toward certain shows or programmes, the portable nature of mobile TV means there will be a demand for individual streams and so-called niche or long-tailed content.
Meeting this demand requires using a mix of broadcast, multicast and unicast technologies.
Typically, this is done by broadcasting the most popular TV channels on bandwidth that is set aside and efficiently managed through dynamic multiplexing.
Other TV channels are multicast based on the demand in each particular cell, while interactive services and niche content are serviced over unicast links. How these various services are packaged and sold to the viewers will evolve over time as the market emerges.
Making this hybrid approach to mobile video delivery successful involves not just the use of a WiMAX network itself, but the implementation of an architecture specifically optimised for WiMAX-based mobile video delivery.
It is this type of architecture that can transform a typical WiMAX network into a WiMAX TV network.
An optimised WiMAX TV architecture is based on the Multicast-Broadcast Services (MBS) specification, which is part of the Mobile WiMAX (802.16e) standard.
MBS supported by Mobile WiMAX (802.16e) leverages the most successful features of such technologies as DVB-H, DVB-SH, MediaFLO and 3GPP E-UTRA.
It offers high data rates and coverage using a Single Frequency Network (SFN); a flexible allocation of radio resources; low mobile-station power consumption; support for datacasting in addition to audio and video streams and fast channel-switching.
Because this architecture is fully IP-based, it enables operators to use standard network and headend components, as well as their existing terminal applications. A complete infrastructure overhaul or rebuild is not necessary.
In addition, the architecture is scalable over a practically unlimited number of users, flexible in content trafficking, and centrally managed and monitored.
The Single Frequency Network (SFN) architecture brings an additional gain of several dBs in the radio channel, thus improving reception quality.
'Time-slicing' technology, successfully implemented in DVB-H and other broadcast standards, is designed to increase the lifetime of the terminal's battery by receiving the content in short bursts, rather then continuously.
While developing WiMAX TV architecture may not involve a heavy infrastructure upgrade, it is necessary to integrate software to manage the network's operations. UDcast has recently developed three software modules designed to meet this need including a WiMax TV Manager, the WiMAX TV ASN/MBS (Mobile Base Station) Module and the WiMAX TV Base Station Module.
Together all of these modules ensure the management of the entire WiMAX TV network, as well as the integration of the broadcast/multicast system with content sources, service protection and interactive services.
The MBS module ensures the correct level of synchronisation of the base stations for SFN operation, plus Inter-bursts Forward Error Correction (iFEC), intra-BS handover and content time-slicing.
The WiMAX TV Base Station Module enforces SFN broadcasting and time-slicing and executes procedures for local content adaptation or injection, enabling geographically addressable content distribution.
These modules demonstrate the feasibility of using WiMAX to deliver broadcast-quality programming to mobile devices. Harnessing the power of WiMAX to enable such a service offers numerous benefits to players across all segments of the industry.
IP and telecom infrastructure providers can use it as revenue-generating extension of their existing WiMAX solutions. Similarly, broadcast TV providers can use it as an innovative WiMAX extension to their existing broadcast operations, or as a direct television distribution channel to the fast-growing community of WiMAX users.
Even though new applications and models won't be discovered until operators and other users begin to implement WiMAX as a mobile video delivery tool, there are emerging applications and business models for WiMAX TV today.
Filip Gluszak is the vice president of marketing for UDcast. David Richardson is the company's vice president of corporate and business development.
The release of the N810 handset follows on from the launch of Nokia's handheld DVB-H DTV receiver, the SU33W, earlier this year.
"By delivering the kind of open Internet experience consumers previously only expected on a desktop PC, the Nokia N810 WiMAX Edition is a compelling example of how next generation broadband wireless technology will transform the very nature of the internet itself," claims Ari Virtanen, vice president of convergence products, Nokia.
A key challenge facing mass market uptake of WiMAX technology has been the lack of available handsets, however this situation is set to improve over the next 12 months, claims Noel Kirkaldy, director of wireless broadband for Motorola Home & Networks Mobility in Middle East and Africa (MEA).
"The initial market to go after [in the region] is the alternative DSL market with WiMAX," he says.
"What you're going to see towards the end of this year and the beginning of next is mobile devices with GSM, wi-fi and WiMAX.
"In fairness, we think it's going to take time for the industry to move towards full mobility and the proliferation of embedded devices, but certainly for a fixed environment, it's good to go."
However, Javier Álvarez, partner at consultancy group, Delta Partners, believes increased broadband penetration will result from the implementation of a combination of platforms.
"WiMAX is the flavour of the month, but there are many other technologies," he says. "For the customer, it's about the service they receive and not the technology," he said.