Showing papers by "Motorola published in 2004"

Room-temperature ferroelectricity in strained SrTiO3.

Abstract: Systems with a ferroelectric to paraelectric transition in the vicinity of room temperature are useful for devices. Adjusting the ferroelectric transition temperature (T(c)) is traditionally accomplished by chemical substitution-as in Ba(x)Sr(1-x)TiO(3), the material widely investigated for microwave devices in which the dielectric constant (epsilon(r)) at GHz frequencies is tuned by applying a quasi-static electric field. Heterogeneity associated with chemical substitution in such films, however, can broaden this phase transition by hundreds of degrees, which is detrimental to tunability and microwave device performance. An alternative way to adjust T(c) in ferroelectric films is strain. Here we show that epitaxial strain from a newly developed substrate can be harnessed to increase T(c) by hundreds of degrees and produce room-temperature ferroelectricity in strontium titanate, a material that is not normally ferroelectric at any temperature. This strain-induced enhancement in T(c) is the largest ever reported. Spatially resolved images of the local polarization state reveal a uniformity that far exceeds films tailored by chemical substitution. The high epsilon(r) at room temperature in these films (nearly 7,000 at 10 GHz) and its sharp dependence on electric field are promising for device applications.

A review of routing protocols for mobile ad hoc networks

Abstract: The 1990s have seen a rapid growth of research interests in mobile ad hoc networking. The infrastructureless and the dynamic nature of these networks demands new set of networking strategies to be implemented in order to provide efficient end-to-end communication. This, along with the diverse application of these networks in many different scenarios such as battlefield and disaster recovery, have seen MANETs being researched by many different organisations and institutes. MANETs employ the traditional TCP/IP structure to provide end-to-end communication between nodes. However, due to their mobility and the limited resource in wireless networks, each layer in the TCP/IP model require redefinition or modifications to function efficiently in MANETs. One interesting research area in MANET is routing. Routing in the MANETs is a challenging task and has received a tremendous amount of attention from researches. This has led to development of many different routing protocols for MANETs, and each author of each proposed protocol argues that the strategy proposed provides an improvement over a number of different strategies considered in the literature for a given network scenario. Therefore, it is quite difficult to determine which protocols may perform best under a number of different network scenarios, such as increasing node density and traffic. In this paper, we provide an overview of a wide range of routing protocols proposed in the literature. We also provide a performance comparison of all routing protocols and suggest which protocols may perform best in large networks.

Self-contained, fully integrated biochip for sample preparation, polymerase chain reaction amplification, and DNA microarray detection.

Abstract: A fully integrated biochip device that consists of microfluidic mixers, valves, pumps, channels, chambers, heaters, and DNA microarray sensors was developed to perform DNA analysis of complex biological sample solutions. Sample preparation (including magnetic bead-based cell capture, cell preconcentration and purification, and cell lysis), polymerase chain reaction, DNA hybridization, and electrochemical detection were performed in this fully automated and miniature device. Cavitation microstreaming was implemented to enhance target cell capture from whole blood samples using immunomagnetic beads and accelerate DNA hybridization reaction. Thermally actuated paraffin-based microvalves were developed to regulate flows. Electrochemical pumps and thermopneumatic pumps were integrated on the chip to provide pumping of liquid solutions. The device is completely self-contained: no external pressure sources, fluid storage, mechanical pumps, or valves are necessary for fluid manipulation, thus eliminating possibl...

The H.264/AVC Advanced Video Coding Standard: Overview and Introduction to the Fidelity Range Extensions

Abstract: H264/MPEG-4 AVC is the latest international video coding standard It was jointly developed by the Video Coding Experts Group (VCEG) of the ITU-T and the Moving Picture Experts Group (MPEG) of ISO/IEC It uses state-of-the-art coding tools and provides enhanced coding efficiency for a wide range of applications, including video telephony, video conferencing, TV, storage (DVD and/or hard disk based, especially high-definition DVD), streaming video, digital video authoring, digital cinema, and many others The work on a new set of extensions to this standard has recently been completed These extensions, known as the Fidelity Range Extensions (FRExt), provide a number of enhanced capabilities relative to the base specification as approved in the Spring of 2003 In this paper, an overview of this standard is provided, including the highlights of the capabilities of the new FRExt features Some comparisons with the existing MPEG-2 and MPEG-4 Part 2 standards are also provided

Superlattices of Iron Nanocubes Synthesized from Fe[N(SiMe3)2]2

Abstract: The reaction of the metal-organic precursor Fe[N(SiMe3)2]2 with H2 in the presence of a long-chain acid and a long-chain amine in various proportions produces monodisperse zerovalent iron nanoparticles. These Fe particles display magnetic properties that match those of bulk iron as evidenced by magnetic and Mossbauer measurements. The nanoparticles adopt a cubic shape with edges of 7 nanometers and are incorporated into extended crystalline superlattices containing nanocubes in close proximity and with their crystallographic axes aligned. These superlattices are formed in solution, precipitate in high yield, and may be redissolved and redeposited as two-dimensional arrays.

Video coding using the H.264/MPEG-4 AVC compression standard

Abstract: H.264/MPEG-4 AVC is a recently completed video compression standard jointly developed by the ITU-T VCEG and the ISO/IEC MPEG standards committees. The standard promises much higher compression than that possible with earlier standards. It allows coding of non-interlaced and interlaced video very efficiently, and even at high bit rates provides more acceptable visual quality than earlier standards. Further, the standard supports flexibilities in coding as well as organization of coded data that can increase resilience to errors or losses. As might be expected, the increase in coding efficiency and coding flexibility comes at the expense of an increase in complexity with respect to earlier standards. In this paper, we first briefly introduce the video coding tools that the standard supports and how these tools are organized into profiles. As with earlier standards, the mechanism of profiles allows one to implement only a desired subset of the standard and still be interoperable with applications of interest. Next, we discuss how the various video coding tools of the standard work, as well as the related issue of how to perform encoding using these tools. We then evaluate the coding performance in terms of contribution to overall improvement offered by individual tools, options within these tools, and important combinations of tools, on a representative set of video test sequences and movie clips. Next, we discuss a number of additional elements of the standard such as, tools that provide system support, details of levels of profiles, and the issue of encoder and decoder complexity. Finally, we summarize our overview and analysis of this standard, by identifying, based on their performance, promising tools as well as options within various tools. r 2004 Elsevier B.V. All rights reserved.

Method and apparatus for a source-initiated handoff from a source cellular wireless network to a target non-cellular wireless network

Abstract: To address the need for an apparatus and method for handoff from a cellular wireless network to a non-cellular wireless network (WLAN, e.g.), the present application describes an access gateway (214) and a dual mode mobile station (201) that enable such handoffs. Dual mode MSs can determine when a handoff to a non-cellular network is preferred and request a handin (302) from the non-cellular network. The access gateway provides information to the MS (304) so that it can initiate a handoff through the serving cellular network. Triggering handoffs in this manner, allows cellular networks to handle handoffs to non-cellular networks in much the same way they handle inter-MSC handoffs today, i.e., source initiated.

Agile software development in large organizations

Abstract: The need to see compelling evidence before adopting new methods looms greater in large organizations because of their complexity and the need to integrate new technologies and processes with existing ones. To further evaluate agile methods and their underlying software development practices, several Software Experience Center (SEC) member companies initiated a series of activities to discover if agile practices match their organizations' needs. Although each organization evaluated agile methods according to its specific needs, here we attempt to generalize their findings by analyzing some of their common experiences in the particular context of large organizations with well-established structures and processes. We base this analysis on experience collected and shared among four SEC members namely ABB, DaimlerChrysler, Motorola, and Nokia.

A Conducting Polymer Nanojunction Sensor for Glucose Detection

Abstract: This paper presents a glucose sensor using conducting polymer/enzyme nanojunctions and demonstrates that unique features can arise when shrinking a sensor to the nanometer scale. Each nanojunction is formed by bridging a pair of nanoelectrodes separated with a small gap (20−60 nm) with polyaniline/glucose oxidase. The signal transduction mechanism of the sensor is based on the change in the nanojunction conductance as a result of glucose oxidation induced change in the polymer redox state. Due to the small size of the nanojunction sensor, the enzyme is regenerated naturally without the need of redox mediators, which consumes minimal amount of oxygen and at the same time gives very fast response (<200 ms). These features make the nanojunction sensor potentially useful for in vivo detection of glucose.

Communications system with radio device and server

Abstract: A communications system having a first server (205) with an electronic mail (e-mail) database for managing e-mail accounts, for storing radio device addresses associated with those accounts, and for storing electronic mail messages associated with those accounts. Each message has a header and text. A gateway connects the first server to a two-way radio network. A radio device (200) has a electronic messaging application. The radio device is capable of two-way communication over the two-way radio network. The first server comprises message handling software arranged to send, to the radio device, a portion of a message of a predetermined size, including a header portion and a text portion. The radio device (200) can request more of a message.

Method and apparatus for relay facilitated communications

Abstract: Communications sourced by a remote unit (14) that is already within reception range of a base site (10) can nevertheless be further facilitated through allocation of one or more relay resources (15, 16). Such relay resources, properly employed, then serve to effectively increase the quality of service for the facilitated communication. This, in turn, can permit the use of, for example, increased data rates for communications from a relatively low power remote unit.

Enhanced passive scanning

Abstract: The invention provides an enhanced passive scanning method for a wireless local area network, including the steps of receiving (405) at least one of a beacon signal (342, 348) or a gratuitous probe response (344), updating (435) a site timing table entry in a site timing table based on the received beacon signal (342, 348) or gratuitous probe response (344), setting (445) a scan start time based on entries in the updated site timing table, and determining (450) a power mode for a wireless communication device based on the scan start time. An enhanced passive scanning system (200, 500, 600) and computer usable medium for enhanced passive scanning is also disclosed.

Incremental redundancy hybrid ARQ schemes based on low-density parity-check codes

Abstract: We study the throughput of hybrid automatic retransmission request (H-ARQ) schemes based on incremental redundancy (IR) over a block-fading channel. We provide an information-theoretic analysis assuming binary random coding and typical-set decoding. Then, we study the performance of low-density parity-check (LDPC) code ensembles with iterative belief-propagation decoding, and show that, under the hypothesis of infinite-length codes, LDPCs yield almost optimal performance. Unfortunately, standard finite-length LDPC ensembles incur a considerable performance loss with respect to their infinite-length counterpart, because of their poor frame-error rate (FER) performance. In order to recover part of this loss, we propose two simple yet effective methods: using a modified LDPC ensemble designed to improve the FER; and using an outer selective-repeat protocol acting on smaller packets of information bits. Surprisingly, these apparently very different methods yield almost the same performance gain and recover a considerable fraction of the optimal throughput, thus making practical finite-length LDPC codes very attractive for data wireless communications based on IR H-ARQ schemes.

Keyboard error reduction method and apparatus

Abstract: In a mobile telephone (10) with a virtual keyboard and a touch screen (12), with individual virtual keys (22) having their own representative positions. During a selection operation to select a key (22), where the touch screen is touched becomes the selected position. The distance between the selected position and adjacent representative positions is used to decide a first set of candidate keys. These candidate keys are then used to provide a set of potential words that would result from the input of any one of those keys. A list of candidate words is then produced and displayed on a display area (26) based on the frequency of use of the words in the set of potential words and the distances between the selected position and the representative position of the keys (22). Once a key (22) is confirmed as having been selected, the offset between the selected position and the representative position of that key is used to re-calibrate that representative position.

Interworking techniques and architectures for WLAN/3G integration toward 4G mobile data networks

Abstract: The intense wireless LAN standardization and R&D activities worldwide, combines with the recent successful deployment of WLANs, provide prime evidence that WLAN technology will play a key role in the fourth generation of mobile data networks. In this context, there is a strong need to integrate WLANs with 3G mobile data networks and develop hybrid mobile data networks capable of ubiquitous data services and very high data rates in strategic locations. This article addresses this need by proposing and discussing some novel architectures able to provide internetworking between WLAN and 3G networks, and meet the requirements of the most common internetworking scenarios. These architectures can enable 3G subscribers to benefit from high-throughput IP connectivity in hotspots and also to attain service roaming across several radio access technologies, such as IEEE 802.11, HiperLan/2, ULTRAN, and GERAN.

Fermi-level pinning at the polysilicon/metal-oxide interface-Part II

Abstract: We report here that Fermi pinning at the polysilicon/metal-oxide interface causes high threshold voltages in MOSFET devices. In Part I, we investigated the different gatestack regions and determined that the polysilicon/metal oxide interface plays a key role on the threshold voltages. Now in Part II, the effects of the interfacial bonding are examined by experiments with submonolayer atomic-layer deposition (ALD) metal oxides and atomistic simulation. Results indicate that pinning occurs due to the interfacial Si-Hf and Si-O-Al bonds for HfO/sub 2/ and Al/sub 2/O/sub 3/, respectively. Oxygen vacancies at polysilicon/HfO/sub 2/ interfaces also lead to Fermi pinning. This fundamental characteristic affects the observed polysilicon depletion.

The Chimaera reconfigurable functional unit

Abstract: By strictly separating reconfigurable logic from the host processor, current custom computing systems suffer from a significant communication bottleneck. In this paper, we describe Chimaera, a system that overcomes the communication bottleneck by integrating reconfigurable logic into the host processor itself. With direct access to the host processor's register file, the system enables the creation of multi-operand instructions and a speculative execution model key to high-performance, general-purpose reconfigurable computing. Chimaera also supports multi-output functions and utilizes partial run-time reconfiguration to reduce reconfiguration time. Combined, the system can provide speedups of a factor of two or more for general-purpose computing, and speedups of 160 or more are possible for hand-mapped applications.

Method and apparatus for multi-antenna transmission

Abstract: In a multiple-input, multiple-output (MIMO) communication system, a method and apparatus for multi-antenna transmission In accordance with the preferred embodiment of the present invention a reduced number of transmit weight matrices are fed back to the transmitter Each transmit weight matrix is then applied to a plurality of subcarriers Because each transmit weight matrix is applied to more than one subcarrier, the amount of weight matrixs being fed back to the transmitter is greatly reduced

Dynamic spectrum allocation in composite reconfigurable wireless networks

Abstract: Future wireless systems are expected to be characterized by increasing convergence between networks and further development of reconfigurable radio systems. In parallel with this, demand for radio spectrum from these systems will increase, as users take advantage of high quality multimedia services. This article aims to investigate and review the possibilities for the dynamic allocation of spectrum to different radio networks operating in a composite reconfigurable wireless system. The article first looks into the current interest of regulators in this area, before describing some possible schemes to implement dynamic spectrum allocation and showing some example performance results. Following this, the technical requirements that a DSA system would have, in terms of reconfigurable system implementation, are discussed.

Fast call set-up for multi-mode communication

Abstract: Fast call set-up for a call to a multi-mode communication unit (102) is facilitated by a method and apparatus for registering and re-registering priorities with a SIP registrar (111). A list of contacts with first priorities associated with a mode of operation in a first enterprise network (106) is established and used. A switch to second priorities is made when a probability of a switch from the first mode of operation to a second mode of operation in a second cellular network (108) satisfies a threshold. The list of contacts includes a contact having an expiration time for the first mode of operation. A quality factor is determined and the list of contacts is re-registered and the expiration time changed if the quality factor does not satisfy a threshold.

Enhanced uplink rate selection by a communication device during soft handoff

Abstract: A method for rate selection by a communication device for enhanced uplink during soft handoff in a wireless communication system includes a first step of receiving information from a scheduler. This information can include one or more of scheduling, a rate limit, a power margin limit, and a persistence. A next step includes determining a data rate for an enhanced uplink during soft handoff using the information. A next step includes transmitting to a serving base station on an enhanced uplink channel at the data rate determined from the determining step.

System and method for building wireless applications with intelligent mapping between user interface and data components

Abstract: A system and method for generating a screen element, based on a data object, of a component application is disclosed. The component application includes a data component having a data field definition and a screen component having a screen element definition. A mapping manager identifies a mapping present in the screen component. The mapping specifies dynamic relationships between the screen component and the data component by an identifier, and for selecting the data component mapped by the mapping according to the mapping identifier. The mapping manager maintains dynamic integrity and automatically synchronizes changes between the screen component and the corresponding data component. A data manager obtains a data object field value corresponding to the data field definition of the mapped data component; and a presentation manager generates a screen element from the screen element definition to include the data object field value.

Single-use, thermally actuated paraffin valves for microfluidic applications

Abstract: A new thermally actuated valving concept using paraffin as single-use valving material was developed. The paraffin undergoes a phase transition in response to changes in temperature. A variety of single-use paraffin-based microvalves, including “close–open,” “open–close–open,” “T,” and toggle designs, were demonstrated. Fluidic experiments showed that these microvalves had zero leakage and a maximum hold-up pressure of 40 psi in a “closed” position. A DNA polymerase chain reaction microdevice containing paraffin-based microvalves to enclose the sample solution in the reaction chamber during the thermal cycling was demonstrated. The paraffin-based microvalving technique has advantages over many existing active microvalve approaches, including a simple design, ease of fabrication, low cost, and ease of integration into complex microfluidic systems. Moreover, this technique is particularly attractive for single-use and disposable microfluidic devices.

Crystallization in hafnia- and zirconia-based systems

Abstract: Crystallization of hafnia and zirconia and their alloys with silica and lanthana was studied in bulk and thin film samples by thermal analysis, X-ray diffraction and electron microscopy. Crystallization temperatures of hafnia and zirconia increase by more than 300 °C with increase of surface/interface area of the amorphous phase. Crystallization temperatures of zirconia and hafnia alloys with silica and lanthana increase with dopant content and exceed 900 °C for 50 mol% SiO2 and LaO1.5. Energies for tetragonal HfO2 and ZrO2 interfaces with amorphous silica were derived from their crystallization enthalpies from silicates as 0.25 ± 0.08 and 0.13 ± 0.07 J/m2, respectively. The crystallization pathways in bulk powders and films of zirconia and hafnia can be interpreted as resulting from thermodynamic stabilization by the surface energy term of tetragonal and amorphous phases over monoclinic. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Aluminium interatomic potential from density functional theory calculations with improved stacking fault energy

Abstract: A new Al potential with improved stacking fault energy is constructed using the force-matching method. The potential is fitted to an ab initio forces database and various experimental data. By using a slightly larger cut-off, we found that the new potential gives the relaxed stacking fault energy in the experimental range without changing the excellent thermal and surface properties of the original force-matching Al potential given by Ercolessi and Adams (1994 Europhys. Lett. 26 583).

Method and apparatus for channel quality feedback within a communication system

Abstract: A base station (101) will request the transmission of quality information from a particular remote stations (102, 103) only when data is queued to be transmitted to the remote stations. Once a remote station begins the transmission of channel quality information, the transmission of such information continues until the data transmission is successfully delivered to the remote station. The base station receives the channel quality information and adjusts the modulation and coding of the remote stations accordingly. Where data is transmitted simultaneously to a plurality of remote stations, a set of queues (303) for the multiple remote stations is maintained, and based on queue status, a channel quality request messages is sent to a sub-set of remote stations with data queued.

Wireless messaging device with selectable scroll display and message pre-fetch

Abstract: A system, method and computer readable medium for scroll displaying of message information stored in message memory (418) of a wireless messaging device (400). The wireless messaging device (400) fetches additional message information from a wireless messaging server (112) over a wireless network, and stores in message memory (418) the additional message information received over the wireless network prior to reaching the end of scroll displaying the stored message information. Additionally, a plurality of received messages can be scroll displayed according to a message receive order or other priority.

IP mobile multicast: Challenges and solutions

Abstract: This article outlines the challenges of IP multicast over Mobile IP Then it provides a comprehensive overview of existing multicast solutions to handle mobile sources and receivers in both the Mobile IPv4 and the Mobile IPv6 environments The solutions are classified into different classes in light of how the network infrastructure is used and the nature of the multicast members (receivers or sources) For each solution, we present a brief overview; we describe the architecture and the proposed protocol; we discuss the advantages and the limitations; and we compare qualitatively all the solutions of each class based on common criteria such as optimal routing, join latency, handover transparency, etc

Segmented and distributed path optimization in a communication network

Abstract: The invention provides for path optimization for routing of a communication session in a network having a plurality of core networks (110) coupled to a plurality of access networks (120). Both a core network and an access network perform the path optimization by determining a plurality of possible paths to a plurality of target access points to form a target matrix, determining a corresponding route preference factor for each possible path of the target matrix, and selecting, from the target matrix, a possible path having an optimal route preference factor. An overall or complete path, for routing of the communication session, is then determined either by combining the selected possible paths, or by selecting one possible path as a complete path. The route preference factor, for each possible path, is determined based upon various routing variables, such as quality of service, bandwidth for the communication session, route complexity, interconnect cost, routing cost; resource loading, resource availability, and operator preference for traffic biasing.

Method and apparatus for transmission and reception within an ofdm communication system

Abstract: A communication system (fig. 4) comprising a first multicarrier transmitter (401/506) outputting a first spread pilot signal (504) over a first spreading block interval on a first plurality of subcarrier (fig. 5). A second multicarrier transmitter (401/506) outputting a second spread pilot signal (504) on the first plurality of subcarriers within the spreading block interval, wherein for each of the plurality of subcarriers, the second spread pilot signal differs form the first pilot signal by a predetermined amount.