Abstract
The continuous growth of the available throughput, specially in the uplink of mobile phone networks is opening the doors to new services and business opportunities without references in the past. In more concrete, new standards HSDPA/HSUPA, introduced to complement and enhance 3G networks, together with the advances in audio and specially video coding, like those adopted by the standard H.264 AVC have boosted the appearance of a new service: exploiting the mobile telephony networks for contributing broadcast quality videos. This new service is offering just now a low cost, high flexibility alternative that, in a brief period of time, will substitute the current Electronic News Gathering (ENG) Units, giving rise to what is being to be called Wireless Journalism (WENG1 or WiNG2). This chapter discusses both the technologies involved and the business opportunities offered by this sector. Once reviewed the state of the art, different solutions will be compared, some of them recently appeared as commercial solutions, like QuickLink 3.5G Live Encoder3 or AirNow!4 and others still in research and development processes.
TopKey Factors In The Evolution Of Mobile Networks Up To Hsupa And Beyond
Limitations of first and second generation mobile telephony standards produced that the Third Generation Partnership Project (3GPP), which includes hardware manufacturers and telephony operators, started developing a new mobile telecommunications system, called Universal Mobile Telecommunications System (UMTS) or 3G. The objective was to develop a mobile telephony system that was not limited to a certain region or country. Besides, it should improve the efficiency of previous standards like GSM (Global System for Mobile communications) and provide better packet-based services.
One of the reasons why these improvements could be achieved is the new radio access schema proposed for these UMTS networks, WCDMA (Wideband Code Division Multiple Access), which works better than Time Division Multiple Access (TDMA) under certain conditions and provides higher efficiency for packet transmission mode.
WCDMA technology uses a Spread Spectrum technique whose main principle is shown in figure 1. The data signal is multiplied by a user-specific pseudo-noise code, spreading the signal throughout the whole band. The receptor extracts the data signal using the same code, as shown in figures 2 and 3.
Figure 1. Spread Spectrum technique used in WCDMA
Figure 2. Spreading and De-spreading of a signal
Figure 3. Use of a correlation receiver
Key Terms in this Chapter
DVB: Digital Video Broadcasting, standard used for digital television throughout the world. It has different definitions for Satellite, Terrestrial and Handheld devices.
Broadcast Quality: referring to a video stream, this quality level states that the video stream is suitable for being included in normal TV broadcasting.
H.264: State of the art video encoding system that achieves very high compression rates with very little objective degradation of the video signal.
Mobile Unit: TV production unit that can be used outdoor, and can be located in different places.
Video Streaming: Video transmission capable of playing the received video as it reaches its destination, without the need of saving it to local disk.
ENG: Electronic News Gathering, a common TV production method that consists in the use of light mobile units to gather audio and video for information programmes.
HSUPA: High Speed Uplink Packet Access, the 06 Release of UMTS. This standard provides several improvements to the basic UMTS data transmission standard.