If a radio can emit sound quality akin to or perhaps better than a CD player and provide lyrics on liquid crystal display, the seemingly primitive device, invented in 1873 by British physicist James Maxwell, may yet get a new lease of life.
This is no flight of fancy. A group of researchers from Shanghai Jiao Tong University has for the first time in the country developed a major preparatory software for this broadcasting breakthrough. But they have delayed further development of transferring the software into hardware.
"Though we have used a most succinct method to wrap up music into transmittable pack ready for digital transmission, we have little confidence in its application for digital broadcasting in the city," Chen Jian, director of Signal Processing Institute at Jiao Tong who led the four-member team, said, explaining the delay.
Chen signed a contract with Victor Co. of Japan in early 1998 to do research on Psychoacoustic model and Filterbanks - two softwares for digital signal processors - which are top sound-compressing technologies, even better than AC-3 used in DVDs and MP-3. Having developed the software for JVC, the team has been looking for some positive moves from the city.
But officials claim the logistics of applying this software in the city are too complicated and expensive.
"Digital broadcasting is an ideal media but we need to spend about US$1 million for setting up a whole satellite transmission system, apart from the sound-compressing technology," said Jin Wei, deputy director of Shanghai Radio and TV Satellite Earth Station. "What's more, we have to buy a new generation of radio receivers, each costing US$1,000."
Unlike frequency modulation or FM broadcasts which rely on MPEG-1 sound processing, used in VCDs, most digital audio broadcasts depend on Advanced Audio Coding or AAC - which can reach CD-sound quality, Chen said.
In addition to the high audio quality, digital transmission is not affected even if the radio is playing in a car racing at 200 kilometers per hour.
While the future of this next-generation transmission in the city remains unclear, this summer will see the debut of digital audio broadcasting in the United States using three satellites, Popular Science reported.
(Eastday.com 06/19/2001)
