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|STMicroelectronics Celebrates Ten Years of Leadership in Digital Radio Technology|
Geneva, - Semiconductor manufacturer STMicroelectronics is celebrating ten years at the forefront of digital radio technology. The company is now the world’s leading supplier of the microchip components that power the digital satellite radio receivers made by the leading manufacturers like Pioneer, Delphi, and Samsung, and has supplied a total of more than 30 million microchips for this application.
“We signed our first agreement with Worldspace Satellite Radio in 1996 and continue to supply chipsets that power Worldspace receivers, built by BPL, Flextronics and Tongshi,” said Ugo Carena, Corporate VP and General Manager of ST’s Automotive Product Group. “Two years later, we began our successful collaboration with XM Satellite Radio in the US. This collaboration has been extended to develop several generations of devices with XM and is ongoing. Throughout this period, we’ve developed considerable expertise in this field and currently our devices power the majority of digital satellite radio receivers in the US”
ST has used this expertise, together with its proven design and manufacturing capacity, to expand its presence in the US Digital Satellite Radio market; in 2004 the company signed an agreement with Sirius Satellite Radio and it is now successfully producing the third generation of the chipset for Sirius’ digital receivers.
Over the last ten years the advantages of digital radio, including near- CD music quality, no interference, and useful text readouts accompanying the audio signal, have been appreciated by a growing number of listeners. US-based satellite broadcasters have over 12 million paying subscribers who enjoy several hundred channels of specialized music programming, leading-edge comedy, and sports reporting. In Europe, terrestrial digital radio is increasingly being adopted by both public and private broadcasters. The number of digital radios sold in the UK outstripped the number of conventional receivers for the first time in 2005.
Digital broadcasting makes more efficient use of the radio spectrum than analog broadcasting – several digital channels can fit into the bandwidth occupied by one conventional FM channel. But the clarity of digital radio depends on extremely sophisticated signal processing techniques. First, the audio signal is elaborated by eliminating redundancy in order to make efficient use of the transmission channel; this task is comparable to the compression performed on MP3 music files. Then, the audio data are processed to compensate for errors that occur during transmission. The errors result from interference or the reflection of signals off buildings and other obstacles. These errors can be corrected using coding techniques like convolutional codes decoded using the Viterbi algorithm, Reed Solomon codes, and turbo codes. The ST chips used in the receivers reassemble the signal into a near-perfect audio image that delivers unsurpassed high-quality sound for the pleasure of the listener.
These advanced techniques require signal-processing operations of considerable complexity and precision, as well as the capability to process RF signals in the ultra-high 2.5GHz frequencies used for satellite broadcasting. Here is STMicroelectronics’ expertise and capability: mastering the entire system, from the RF to the intensive signal processing performed in the baseband, and offering a broad VLSI and RF process portfolio and extensive manufacturing capacity.
“We were the first to fit a complete digital satellite decoding circuit onto a single chip,” said Carena. “This kind of integration is driving the development of the latest generation of ultra-compact portable digital radios. In this kind of device, the key factors are outstanding integration and low power consumption to maximize battery life. STMicroelectronics has set new standards in these devices in size and power economy.”
The digital radio revolution in satellite is about to be extended to FM broadcasting and the lower-frequency AM and shortwave bands. This is being done through the introduction of two new technologies in which ST is contributing its expertise: HD RadioTM and DRMTM.
These new standards play to ST’s strengths in conventional radio technology and the special know-how we’ve developed in digital signal processing,” commented Carena. “Having signed an agreement with Ibiquity to develop an HD Radio, STMicroelectronics is well placed to keep its leading position as the silicon provider to the next generation of digital radio receivers.”
“The penetration of digital radio over the last ten years has been driven by listeners’ demands for more choice and higher quality,” Carena continued. “That choice is now going to be available to an even wider audience as digital broadcasting spreads across the radio spectrum. STMicroelectronics has played an important role in developing the key enabling technologies for this medium and we will continue to do so in whichever directions it evolves.”
HD Radio™ makes use of the lean bandwidth requirements of digital signals to slip the new channels between existing programming in the FM and AM bands, creating high-quality alternatives to the analog channels. Many networks will broadcast their programming in both analog and digital formats on adjacent wavelengths. Like satellite subscribers, HD Radio listeners will enjoy clear, interference-free reception with text and image accompaniment carrying useful additional information such as traffic and weather reports for in-car users, as well as artist and album readouts for music listeners.
DRM™, the other new broadcasting standard, uses the shortwave and medium-wave bands, traditionally the province of radio amateurs and shipping broadcasts but used infrequently nowadays for commercial radio. The new digital standard will give shortwave a new lease of life and the long range of shortwave signals will allow broadcasters to cover vast areas with very few transmitters.
Jueves, 14 Diciembre, 2006 - 10:52