Caddock Electronics, Inc.

<p>At this point, SBR technology comes into play. SBR uses a hybrid waveform/parametric coding method. It is based on the fact that in most cases there are dependencies between the lower and higher frequency components of an audio signal. Therefore, the high frequency part of an audio signal can be reconstructed from the low frequency part. Transmission of the high frequency part is therefore not necessary. Only a small amount of SBR control data needs to be carried in the bit stream to guarantee an accurate reconstruction of the high frequencies.</p>

A second example of the weak form of aggregation is where an entity has use or exclusive ownership of another. For example, a Person entity aggregates a set of shares. This implies a Person may be associated with zero or more shares from a Share table, but each Share may be associated with zero orone Person. If the Person ceases to exist, the Shares become un-owned or arepassed to another Person. In the relational world, this could be implemented as each Share having an 'owner' column which stored a Person ID (or OID).

Using existing LMDS infrastructures, we have designed a system that provides network access to a small area-within several kilometers-using radio links. This system offers broadband wireless access to fixed (stationary) nodes in conjunction with wired backbone networks, based on an architecture similar to that of a cellular system, where omnidirectional basestations provide the coverage.

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Similar methodology has been deployed as wireless local loops (WLLs), often for countries without a comprehensive telephone network. WLL is aimed at providing wireless network access without relying on legacy wired infrastructures such as the plain old telephone system (POTS). Since WLL is primarily designed as an alternative for providing telephone service, its supported data speed is very limited, although the technology can be made capable of supporting data rates similar to those of the integrated services digital network (ISDN).

Since LMDS provides point-to-multipoint wireless access services to subscribers within a geographical area far greater than that of WLANs, it is drawing much interest as a potential way to extend services to portable devices. With its promise of higher bandwidth for more subscribers at higher data rates than other wireless distribution technologies, adapting the existing LMDS infrastructure to provide network access to mobile subscribers would be of great interest to consumers eager to get online faster. A conceptual model of such a system provides wider coverage than WLANs and higher data rates than WLLs. But several factors are keeping this out of reach.

The type of antenna used is one consideration, especially when the system is adapted to provide access for mobile subscribers. Typically, an antenna with a narrow beam width of approximately 2 degrees to 3 degrees and gain of 40 dBi, and which maintains a line-of-sight to the basestation antenna, is used. At present, LMDS receivers use antennas of around 0.3 to 0.6 meter in size, because they are roof-mounted and not intended to be mobile. Antennas of this size are far too large for any mobile devices. With additional circuitry needed to form an integral part

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of the wireless access model for consumer equipment, mobility of subscriber devices is very limited. Size and weight of the access modem must therefore be taken into account in system development. Cell overlap control is another consideration in such deployment.

Distinct advantages Although LMDS has distinct advantages over other means of wireless access in terms of network capacity-number of subscribers supported and data rate-it iscurrently impractical to adapt this system for mobile devices. Rudimentary problems associated with its deployment are mainly due to the line-of-sight requirement and the practicality of carrying a too-hefty mobile device. The main challenge is to make the receiver small and light enough for mobile users to tote, and cheap enough to make.

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Field measurements have been conducted to prove the viability of this approach using a 0.3-meter antenna at 26 GHz. To simplify the receiver structure while balancing performance, 4-QAM turns out to be the optimal choice as the modulation scheme for providing wireless network access to mobile subscribers.

This article will be presented at the ICCE show in Los Angeles, in a paper called Modulation Schemes for Broadband Wireless Internet Access.”

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Already reeling from depressed prices and sluggish sales, the industry's top DRAM suppliers were handed unwelcome news this week when the U.S. Justice Department subpoenaed them in an unprecedented investigation into alleged anti-competitive pricing practices.

The collective sense of outrage expressed privately by industry executives lasted only until late Thursday, when Germany's Infineon Technologies A.G. lodged a complaint with the European Union alleging that rivals Samsung Electronics Co. Ltd. and Hynix Semiconductor Inc. have received subsidies that allow them to set prices in a manner that substantiates U.S investigators' claims.

Separately, Micron Technology Inc. is considering filing similar complaints against Hynix and Samsung, EBN has learned.

All the DRAM suppliers subpoenaed by the Justice Department, including the top four vendors — Samsung, Micron, Hynix, and Infineon — and Taiwan's Nanya Technology and Winbond Electronics, proclaimed their innocence and noted that the investigation is in the fact-finding stage.

Similar methodology has been deployed as wireless local loops (WLLs), often for countries without a comprehensive telephone network. WLL is aimed at providing wireless network access without relying on legacy wired infrastructures such as the plain old telephone system (POTS). Since WLL is primarily designed as an alternative for providing telephone service, its supported data speed is very limited, although the technology can be made capable of supporting data rates similar to those of the integrated services digital network (ISDN).

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