MediaFLO™ Overview

Introduction

QUALCOMM has developed an end-to-end solution, referred to as MediaFLO™ System that includes a new multicasting technology and air interface, known as Forward Link Only (FLO™) technology. (Multicast is the delivery of information to multiple destinations simultaneously using the most efficient strategy to deliver the messages over each link of the network only once. By comparison with multicast, conventional point-to-single-point delivery is called unicast, whereas delivery to every node of the network is broadcast). FLO was designed from inception for the efficient and economical distribution of multimedia content to a large number of mobile users. In designing FLO technology, QUALCOMM has effectively addressed key challenges involved in the simultaneous delivery of multimedia content to a large number of handheld devices. These challenges include quality of service, data capacity, power consumption, coverage and mobility. FLO is a system built from the ground-up for mobile multimedia (high-quality video and audio) and offers the best per¬formance and spectral efficiency with minimal power consumption.

MediaFLO™ USA Inc., a wholly-owned subsidiary of QUALCOMM, is currently deploying and will operate a nationwide wireless network using the MediaFLO Media Distribution System (MDS) and FLO technology at the 700 MHz broadcast spectrum (using 6 MHz bandwidth - 716-722 MHz), delivering up to 100 channels of content, including up to 20 live streaming video channels Quarter Video Graphics Array (QVGA) resolution, at up to 30 frames per second (fps), 10 streaming audio channels, 50 to 80 Clipcast™ (short format video cashed on mobile device) channels, and numerous data channels. MediaFLO USA will deliver a nationwide coverage and provide multimedia services to consumers in cooperation with U.S. wireless operators and expects to begin commercial operation of the new network in the second half of 2006.

FLO technology is being made available to an industry-led group for the purpose of bringing a cooperative specification to standards development organizations for consideration for adoption. QUALCOMM is committed to the global standardization of FLO technology and is working with leading compa¬nies worldwide to create a multi-party organization that leads this initiative. QUALCOMM is also exploring FLO commercial deployment opportunities and trials across the globe.

MediaFLO System Features

Content Acquisition, Distribution, and Interactivity

In a MediaFLO network, content that is representative of a linear real-time channel is received directly from content providers, typically via a C-band satellite in standard definition MPEG-2 format, utilizing off-the-shelf infrastructure equipment. The use of a standard definition as a source content provides sufficient resolution to allow for efficient transcoding to the QVGA resolution supported by the FLO network.

“Non-real-time” content is received by a content server, typically via an IP link. The content is then reformatted into FLO packet streams and redistributed over a Single Frequency Network (SFN). This distribution of the FLO packet streams is facilitated by the MediaFLO MDS. This non-real-time content is delivered according to a pre-arranged schedule and stored on the device for later viewing.

Only those devices that have subscribed for the service may receive the content. The content may be stored on the mobile device for future viewing, in accordance to a service program guide, or delivered real-time for live streaming to the user device given a linear feed of content. Content may consist of high-quality H.264 QVGA video, high quality HE-AAC audio, and IP data streams. A 3G cellular network, such as 1XEV-DO, UMTS, or HSDPA, is used for interactivity and user authorization for service. The interactivity provided via the 3G network includes purchase and download.

Power Consumption Optimization and Channel Acquisition

FLO technology simultaneously optimizes power consumption, frequency diversity, and time diver¬sity. Similar, but less efficient, sys¬tems may optimize one or two of these parameters but ultimately compromise the others. FLO has a unique capability that allows it to access a small fraction of the total signal transmitted without compromising either frequency or time diversity. These capabilities allow a FLO enabled mobile device to achieve battery life comparable to a conven¬tional cellular phone; that is, a few hours of viewing and talk time and a few days of stand-by time per battery charge.

The FLO air interface employs Time Division Multiplexing (TDM) to transmit each content stream at specific intervals within the FLO waveform. The mobile device accesses over¬head information to determine which time inter¬vals a desired content stream is transmitted. The mobile device receiver circuitry only powers up during the time periods in which the desired content stream is transmitted; all other times it is powered down. The receiver on time automatically adapts to variable data rates as delivered.

FLO technology minimizes program channel acquisition time. In most cases, it is less than two seconds. Mobile users can channel surf as easily as they would with digital satellite or cable systems at home.

Wide- and Local-Area Content

FLO systems support the coexistence of local and wide-area coverage within a single radio frequency (RF) channel. When FLO is deployed in a single frequency network (SFN) configuration, the need for complex frequency hand¬offs is eliminated. The content for a wide-area network is synchronously transmitted by all of the transmitters. Content of regional or local interest is carried in its specific market.

Layered Modulation

FLO technology supports the use of layered modulation. The FLO data stream for a given service is divided into a base layer that all users can decode, and an enhancement layer that is decoded in areas where a higher signal to noise ratio (SNR) is available. Typically 90% of user devices will be able to receive both layers of the signal for a given service to deliver up to 30 fps video. The base layer has superior coverage as compared to an un-layered mode of similar total capacity and delivers up to 15 fps video. The combined use of layered modulation and source coding allows for graceful degradation of service and the ability to receive in locations or at speeds that could not otherwise have reception. For the end user, this means that a FLO network can provide a better coverage with good quality services, especially video, which requires sig¬nificantly more bandwidth than other multimedia services. The H.264 encoding for real-time media is extended H.264 compliant for non-layered applications, and the base layer is H.264 extended compliant in applications where a layered codec is applied.

Benefits of FLO Technology

The FLO air interface addresses the simultaneous need to optimize power consumption, channel acquisition time and time diversity. It enables the application of statistical multiplexing yielding significant gains realized by encoding real-time media under bit rate control of a statistical multiplexer that allocates bandwidth per service. It also supports per channel quality of service requirements allowing different coding rates and modulation for different applications. These factors combined with the application of a turbo code, allow better performance than any other functionally similar technology (3-5 dB). This translates into more than 40% better coverage for the same service delivery or about twice the capacity for similar coverage. When FLO applies layered modulation and coding this advantage can be extended by an additional 3 dB.

FLO technology provides significant advantages relative to broadcast, and broadcast derivative, formats for the distribution of multimedia to mobile handsets. These benefits are achieved by focusing on the specific challenges associated with mobile multimedia, and optimizing each element to that purpose.

Robert Jarrin
Director, Government Affairs
Qualcomm
[email protected]