Realtek Demonstrates Complete Detect-And-Avoid System for Ultra-Wideband at European Regulatory Meeting

2007/09/12 First industry demonstration of WiMAX® ultra-low- level signal detection combined with advanced avoidance techniques illustrates feasibility of full simultaneous operation of UWB and WiMAX in the 3.4~4.8GHz band

 HSINCHU, Taiwan and IRVINE, Calif. – September 13, 2007 – Realtek Semiconductor Corp., one of the world’s largest IC design houses and a market leader in ultra-wideband (UWB) technology, will demonstrate a complete detect-and-avoid (DAA) prototype system enabling full simultaneous operation of ultra-wideband devices with WiMAX systems at the CEPT Electronic Communications Committee (ECC TG3) meeting in Brest, France, on September 13~14.  Motivated by the goal of enabling use of spectrum for new communication services, DAA technology seeks to detect the presence of licensed and protected services and to adapt dynamically in order to provide no interference to the licensed service. DAA is a particularly critical enabling technology for ultra-wideband systems due to the large UWB occupied bandwidth and the corresponding need to protect many licensed services. DAA functionality will be required for all ultra-wideband operation in the 3.1~4.2GHz band, and will be phased in for the 4.2~4.8GHz band between 2009 and 2011, in the EU, Japan, and Korea. Regulations addressing detailed requirements for detection of protected services and application of avoidance techniques are currently under development in each of these regulatory domains.

The demonstration uses a commercially available WiMAX system with Realtek’s RTU7105 single-chip ultra-wideband MAC and PHY, supplemented by limited external processing. A downlink WiMAX signal, from base station to mobile station, is attenuated to an ultra-low level of -80dBm/MHz and is detected within seconds by the RTU7105/external processor. The RTU7105 responds immediately by transmitting at a power of less than -70dBm/MHz around the detected WiMAX signal, while maintaining the maximum regulated limit of -41.3dBm/MHz elsewhere in the same band. The technology is capable of detecting both downlink and uplink signals in any WiMAX signal format and is also applicable to 3G/4G signals. It distinguishes accurately between the WiMAX/3G/4G signals requiring protection, and spurious emissions requiring no protection. By maintaining full ultra-wideband communication within the same band as the protected service, the prototype meets the most exacting and high-performance definition of DAA, as opposed to systems that react to the detected signal by simply switching to another frequency band or ceasing communication altogether.

“Detect-And-Avoid technology holds the promise of opening up significant areas of common worldwide spectrum for ultra-wideband,” said Stephan ten Brink, UWB technical director at Realtek. “The near-term application enables UWB operation in the higher-range 3.1~4.8GHz band and in addition, DAA has significant potential to open the 6~7.25GHz and 8.5~9GHz regions for worldwide ultra-wideband operation. Looking beyond ultra-wideband, these detect-and-avoid techniques are not dependent on the characteristics of ultra-wideband and can be used to enable coexistence between any wireless technologies.”

The detection algorithms used in the demonstration are designed to be incorporated in the RTU7105 via firmware/software upgrade upon finalization of regulatory requirements.

About the RTU7105
The RTU7105 is a highly-integrated single-chip CMOS solution providing device controller support for Certified Wireless USB and IP-over-UWB, with USB2.0 and SDIO 1.2 interfaces, combined with a multi-protocol MAC and ultra-wideband PHY based on the ISO/IEC-approved ECMA-368 standard. The RTU7105 is the first ultra-wideband chip to provide support for both low (<5GHz) and high (>6GHz) bands, with support for 3.168~4.752GHz and 6.336~7.920GHz operation. The chip supports data rates up to 480Mbps and ten different logical channels per supported band, providing a full match with existing worldwide regulations. For more information on Realtek’s UWB products, visit

About Realtek
Realtek Semiconductor Corp. is one of the world's leading IC providers. It designs and develops a wide range of IC products for communications network, computer peripheral, and multimedia applications. Products include 10/100/1000M Ethernet Controllers, 10/100/1000M Ethernet Switch/Gateway Controllers, 10/100/1000M Ethernet PHYceivers, Wireless LAN Controllers & AP/Router SoCs, ADSL2+ Chips, VoIP Solutions, WiMedia®-based Ultra-Wideband Chips, AC'97/High Definition Audio Codecs, Clock Generators, Card Reader Controllers, and LCD Monitor/LCD TV/DTV Controllers. With advanced design expertise in RF, analog, and mixed signal circuits, and with strong manufacturing and system knowledge, Realtek offers full-featured, high-performance, and competitive total solutions. More information on Realtek can be found on the website:

Editorial Contacts
Sean Coffey
Realtek Semiconductor Corp.

Hunter Chen
Realtek Semiconductor Corp.
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