Showing papers by "Motorola published in 2001"

Reproducible Measurement of Single-Molecule Conductivity

Abstract: A reliable method has been developed for making through-bond electrical contacts to molecules. Current-voltage curves are quantized as integer multiples of one fundamental curve, an observation used to identify single-molecule contacts. The resistance of a single octanedithiol molecule was 900 ± 50 megohms, based on measurements on more than 1000 single molecules. In contrast, nonbonded contacts to octanethiol monolayers were at least four orders of magnitude more resistive, less reproducible, and had a different voltage dependence, demonstrating that the measurement of intrinsic molecular properties requires chemically bonded contacts.

Keys with Upward Wildcards for XML

Abstract: The paper proposes a key constraint language for XML and investigates its associated decision problems. The language is defined in terms of regular path expressions extended with downward and upward wildcards, which can not only move down XML document trees, but also upwards. In a uniform syntax it is capable of expressing both absolute keys and relative keys, which are important to hierarchically structured data. In addition, keys defined in the language can be reasoned about efficiently. The paper provides a sound and complete set of inference rules and a cubic time algorithm for determining implication of the keys.

Space-time transmit precoding with imperfect feedback

Abstract: The use of channel feedback from receiver to transmitter is standard in wireline communications. While knowledge of the channel at the transmitter would produce similar benefits for wireless communications as well, the generation of reliable channel feedback is complicated by the rapid time variations of the channel for mobile applications. The purpose of this paper is to provide an information-theoretic perspective on optimum transmitter strategies, and the gains obtained by employing them, for systems with transmit antenna arrays and imperfect channel feedback. The spatial channel, given the feedback, is modeled as a complex Gaussian random vector. Two extreme cases are considered: mean feedback, in which the channel side information resides in the mean of the distribution, with the covariance modeled as white, and covariance feedback, in which the channel is assumed to be varying too rapidly to track its mean, so that the mean is set to zero, and the information regarding the relative geometry of the propagation paths is captured by a nonwhite covariance matrix. In both cases, the optimum transmission strategies, maximizing the information transfer rate, are determined as a solution to simple numerical optimization problems. For both feedback models, our numerical results indicate that, when there is a moderate disparity between the strengths of different paths from the transmitter to the receiver, it is nearly optimal to employ the simple beamforming strategy of transmitting all available power in the direction which the feedback indicates is the strongest.

Wireless system protocol for telemetry monitoring

Abstract: A wireless, programmable system for medical monitoring includes a base unit (18) and a plurality of individual wireless, remotely programmable biosensor transceivers (20). The base unit (18) manages the transceivers (20) by issuing registration, configuration, data acquisition, and transmission commands using wireless techniques. Physiologic data from the wireless transceivers (20) are demultiplexed and supplied via a standard interface to a conventional monitor (914) for display. Initialization, configuration, registration, and management routines for the wireless transceivers and the base unit are also described.

Group location and route sharing system for communication units in a trunked communication system

Abstract: Methods are disclosed for sharing location and route information between communication units (e.g., talkgroup members) that are subscribed to a group location sharing service. The group location sharing service is event-based, such that the communication units may form a subset of a talkgroup desiring to actively participate or monitor an event. Communication units de-subscribe from the group location sharing service or talkgroup when they no longer desire to participate or monitor the event. Service levels may be determined for various subscribers to the group location sharing service. The service levels may include, for example, an information transmission service level and information reception service level that determine an amount, type, and/or timing of information to be sent or received by particular subscribers.

Method and system of testing continuity for a motor and associated drive circuitry

Abstract: A method and system for checking continuity of a motor (104), motor drive, motor relay (110), dc relay (108) and interconnections (122a-c) thereof for a power steering system (204) produces minimal torque on a motor shaft (426) of the power steering system (204). The position of the motor shaft (426) is located using a sensor. Thereafter, it is determined which switches (106a-f) of an inverter circuitry (100) to switch to produce a minimal torque on the motor shaft (426). The inverter circuit (100) converts dc voltage from a power source (102) to ac voltage required by the motor (104). Thereafter, the switches (106a-f) that produce the minimal torque on the motor shaft (426) are switched and current flow is checked to determine the continuity of the circuitry. To produce minimal torque on the motor shaft (426), the complementary pair of switches (106a-f) to the first pair is then switched.

Microfluidic devices comprising biochannels

Abstract: The present invention is directed to a variety of microfluidic devices with configurations including the use of biochannels or microchannels comprising arrays of capture binding ligands to capture target analytes in samples. The invention provides microfluidic cassettes or devices that can be used to effect a number of manipulations on a sample to ultimately result in target analyte detection or quantification.

Time division protocol for an ad-hoc, peer-to-peer radio network having coordinating channel access to shared parallel data channels with separate reservation channel

Abstract: A novel protocol for an ad-hoc, peer-to-peer radio network that provides collision-free channel access with an emphasis on improving geographic reuse of the frequency spectrum. The protocol of the invention is executed on the reservation or control channel, and provides a method for allocating data transactions on the data channels. The system of the invention utilizes multiple parallel data channels that are coordinated by a single reservation channel. The transceiver of the system employs two modems to solve the channel reliability issues with multiple channel designs, where one is dedicated as a receive-only modem for gathering channel usage information on the reservation channel. High quality voice, video and data may be transmitted. The reservation channel implements a time division multiple access algorithm with dynamic slot allocation. In a distributed manner, nodes determine geographic reuse of slots based on channel quality extracted from the modem. Signal quality calculations are used to determine the likelihood of a slot reuse causing destructive interference within a node's neighborhood. Requests for slot usage are compared with the known traffic pattern and accepted or rejected by nodes within RF signal range based on the signal quality calculations.

Method and apparatus for improving vehicle operator performance

Abstract: A method (700) for improving driver performance includes the steps of receiving vehicle operating data from the vehicle (702); monitoring an interior portion of the vehicle and receiving operator activity data from the interior portion of the vehicle (704); receiving vehicle environment data from the environment external to the vehicle (706); monitoring the vehicle operator and receiving operator condition data relating to a condition of the vehicle operator (708); recording an operator performance assessment based on the vehicle operating data, the operator activity data, the vehicle environment data and the operator condition data (710); and reporting the operator performance assessment to the operator (712).

Pb-free solders for flip-chip interconnects

Abstract: A variety of lead-free solder alloys were studied for use as flip-chip interconnects including Sn-3.5Ag, Sn-0.7Cu, Sn-3.8Ag-0.7Cu, and eutectic Sn-37Pb as a baseline. The reaction behavior and reliability of these solders were determined in a flip-chip configuration using a variety of under-bump metallurgies (TiW/Cu, electrolytic nickel, and electroless Ni-P/Au). The solder micro-structure and intermetallic reaction products and kinetics were determined. The Sn-0.7Cu solder has a large grain structure and the Sn-3.5Ag and Sn-3.8Ag-0.7Cu have a fine lamellar two-phase structure of tin and Ag3Sn. The intermetallic compounds were similar for all the lead-free alloys. On Ni, Ni3Sn4 formed and on copper, Cu6Sn5Cu3Sn formed. During reflow, the intermetallic growth rate was faster for the lead-free alloys, compared to eutectic tin-lead. In solidstate aging, however, the interfacial intermetallic compounds grew faster with the tinlead solder than for the lead-free alloys. The reliability tests performed included shear strength and thermomechanical fatigue. The lower strength Sn-0.7Cu alloy also had the best thermomechanical fatigue behavior. Failures occurred near the solder/intermetallic interface for all the alloys except Sn-0.7Cu, which deformed by grain sliding and failed in the center of the joint. Based on this study, the optimal solder alloy for flip-chip applications is identified as eutectic Sn-0.7Cu.

MRSVP: a resource reservation protocol for an integrated services network with mobile hosts

Abstract: This paper describes a reservation protocol to provide real-time services to mobile users in an Integrated Services Packet Network. Mobility of hosts has significant impact on the quality of service provided to a real-time application. The currently proposed network system architecture and mechanisms to provide real-time services to fixed hosts are inadequate to accommodate the mobile hosts which can frequently change their point of attachments to the fixed network. Mobile hosts may experience wide variations of quality of service due to mobility. To reduce the impacts of mobility on QoS guarantees, a mobile host needs to make advance resource reservations at multiple locations it may possibly visit during the lifetime of the connection. The currently proposed reservation protocol in the Internet, RSVP, is not adequate to make such reservations for mobile hosts. In this paper, we describe a new reservation protocol, MRSVP, for supporting integrated services in a network with mobile hosts.

Leveraging resources in global software development

Abstract: Leveraging global resources for software development is rapidly becoming the norm at Motorola, which has over 25 software development centers worldwide. Our project, called the 3G Trial (Third Generation Cellular System), was the first of its scope and significance developed by a global engineering team at Motorola. Staffing was the most significant issue we encountered in the 3G Trial. We had only about 20 percent of the required staff available at our division headquarters in Burlington Heights, Ill., US, and needed to find the other 80 percent to successfully complete the project. Early on, we concluded that our only means to staff the project was to rely on software development engineers from Motorola's worldwide software centers. We developed the system with staffing from six different countries. Next, we had to integrate the people into a team. While addressing this challenge, we identified key risk factors and developed approaches to reduce them. We separated the project risk factors into the five categories Carmel (1999) describes as the centrifugal forces that pull global projects apart. To pass on the lessons we learned from this project, this article sets out the global development issues we faced, our approaches to resolving them, and our findings compared to other research.

Multicast distribution of presence information for an instant messaging system

Abstract: The present invention is a system, method and network ( 110 ) for multicast distribution of presence information to a plurality of communication devices ( 102, 104, 106, 108 ). A contact list ( 122, 124, 126, 128 ), associated with each communication device, identifies one or more of the other communication devices. The network provides one or more multicast addresses based on the contact lists of the communication devices to the plurality of communication devices. The network also sends multicast messages identified by the one or more multicast addresses to the plurality of communication devices. Each multicast address identifies a group of multicast devices among the plurality of communication devices, and the multicast messages include presence information about the group of multicast devices. A portion of the plurality of communication devices receives the multicast messages identified by the one or more multicast addresses and extracts the presence information about the group of multicast devices from the multicast messages.

Field emission displays: a critical review

Abstract: The goal of making attractive flat panel displays (FPDs) based on arrays of cold cathodes has now become a reality. Pixtech and Futaba have begun commercial production of low voltage, monochrome field emission displays (FEDs). Moreover, public response to the high voltage, full color, VGA FED prototypes shown by Candescent and Motorola at various technical meetings and exhibits has been extremely positive and encouraging. Yet, the future of the FED industry is uncertain. The tremendous improvements in visual quality and reduction in manufacturing cost of liquid crystal displays, as well as the formidable progress made in other FPD technologies has raised the standard for FEDs. In this article, we first review the status of FEDs based on the Spindt microtip emitter. We focus on the scalability of the Spindt process to large substrates, phosphor selection, high voltage stability, and display lifetime. Second, we discuss in detail the recent advances made in alternate cold cathode technology, including carbon nanotubes and composite materials, and their potential advantages for FPD. This new technology offers a tremendous opportunity to lower capital investment, to cut manufacturing costs and to challenge the existing flat panel industry.

Scalable routing protocol for ad hoc networks

Abstract: In this paper we present a scalable routing protocol for ad hoc networks. The protocol is based on a geographic location management strategy that keeps the overhead of routing packets relatively small. Nodes are assigned home regions and all nodes within a home region know the approximate location of the registered nodes. As nodes travel, they send location update messages to their home regions and this information is used to route data packets. In this paper, we derive theoretical performance results for the protocol and prove that the control packet overhead scales linearly with node speed and N3/2 with increasing number of nodes. These results indicate that our protocol is well suited to relatively large ad hoc networks where nodes travel at high speed. Finally, we use simulations to validate our analytical model.

System and method for determining a location relevant to a communication device and/or its associated user

Abstract: A method of determining a location relevant to a user of a communication device is provided. The method involves determining general location information of the location relevant to the user and determining a list of location parameters from the general location information. Specific location of the communication device is also determined. The location relevant to the user is then determined by comparing the list of location parameters with the specific location information. Systems and programs for using the method are also provided.

Network protocol for wireless devices utilizing location information

Abstract: A system and method for establishing a network within a plurality of interconnected and randomly geographically located nodes, such as wireless devices One or more cluster heads are selected within the nodes and selectively communicate with the other cluster heads and nodes The cluster head can be a wireless device or a specific dedicated device such as a router Each cluster head determines the geographical location of that cluster head and the data-dependent nodes of the cluster head, and selectively receives and stores location information of the other cluster heads and dependent nodes to create an optimal data-routing network within the plurality of nodes

Electromigration of eutectic SnPb and SnAg3.8Cu0.7 flip chip solder bumps and under-bump metallization

Abstract: The electromigration damage in flip chip solder bumps of eutectic SnPb and SnAg3.8Cu0.7 was studied after current stressing at 120 °C with 1.5 A. The diameter of the bumps was about 200 μm. The under-bump metallization (UBM) on the chip side was electroless Ni and on the board side was electroplated Cu. Surface marker motion was used to measure the atomic flux driven by electromigration and to calculate the effective charge number, Z*, of the solder. For eutectic SnPb, Z* is about 36–100 after 39.5 h of electromigration, but for SnAg3.8Cu0.7 the marker movement was too small to measure Z* even after 200 h of current stressing. While the effect of electromigration in SnAg3.8Cu0.7 is much smaller than that in eutectic SnPb, hillocks of intermetallic compounds at the anode have been observed in the former. An extensive growth of Ni–Cu–Sn intermetallic compounds in the matrix of both solder bumps was found. A localized dissolution of electroless Ni UBM was observed under current stressing, yet no dissolution ...

Wireless electrocardiograph system and method

Abstract: A method and system for wireless ECG monitoring is provided. An electrode connector, transmitter and receiver operate with existing electrodes and ECG monitors. The electrode connector includes connectors for attaching to disposable or reusable single electrodes. The transmitter transmits the signals from the electrodes to the receiver. The receiver passes the electrode signals to the ECG monitor for processing. ECG monitors used with an electrical conductor, for example wire connections to electrodes, are connected with the receiver, avoiding the purchase of a new monitor. Any legacy ECG monitor, including different ECG monitors, connects with the receiver using the ECG monitor's lead-wires. The ECG monitor operates as if directly connected to the electrodes without the problems discussed above associated with wires running from the ECG monitor to the patient.

Further developments in the local-orbital density-functional-theory tight-binding method

Abstract: Improvements to the Sankey-Niklewaki method [O. F. Sankey and D. J. Niklewski, Phys. Rev. B 40, 3979 (1989)] for computing total energies and forces, within an ab initio tight-binding formalism, are presented here. In particular, the improved method (called FIREBALL) uses the separable pseudopotential (Hamann or Troullier) and goes beyond the minimal ${\mathrm{sp}}^{2}$ basis set of the Sankey-Niklewski method, allowing for double numerical basis sets with the addition of polarization orbitals and d orbitals to the basis set. A major improvement includes the use of more complex exchange-correlation functionals, such as Becke exchange with the Lee-Yang-Parr correlation. Results for Cu and GaN band structures using d orbitals within the improved method are reported; the results for GaN are greatly improved compared to the minimal basis results. Finally, to demonstrate the flexibility of the method, results for the ${\mathrm{H}}_{2}\mathrm{O}$ dimer system and the energetics of a gas-phase octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine molecule are reported.

Vibrational properties of AlN grown on (111)-oriented silicon

Abstract: We study the vibrational spectrum of AlN grown on Si(111). The AlN was deposited using gas-source molecular beam epitaxy. Raman backscattering along the growth c axis and from a cleaved surface perpendicular to the wurtzite c direction allows us to determine the ${E}_{2}^{1},$ ${E}_{2}^{2},$ ${A}_{1}(\mathrm{TO}),$ ${A}_{1}(\mathrm{LO}),$ and ${E}_{1}(\mathrm{TO})$ phonon energies. For a 0.8-\ensuremath{\mu}m-thick AlN layer under a biaxial tensile stress of 0.6 GPa, these are 249.0, 653.6, 607.3, 884.5, and 666.5 ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$, respectively. By combining the Raman and x-ray diffraction studies, the Raman stress factor of AlN is found to be $\ensuremath{-}6.3\ifmmode\pm\else\textpm\fi{}1.4{\mathrm{cm}}^{\ensuremath{-}1}/\mathrm{GPa}$ for the ${E}_{2}^{2}$ phonon. This factor depends on published values of the elastic constants of AlN, as discussed in the text. The zero-stress ${E}_{2}^{2}$ energy is determined to be $657.4\ifmmode\pm\else\textpm\fi{}0.2{\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}.$ Fourier-transform infrared reflectance and absorption techniques allow us to measure the ${E}_{1}(\mathrm{TO})$ and ${A}_{1}(\mathrm{LO})$ phonon energies. The film thickness (from 0.06 to 1.0 \ensuremath{\mu}m) results in great differences in the reflectance spectra, which are well described by a model using damped Lorentzian oscillators taking into account the crystal anisotropy and the film thickness.

Programmable wireless electrode system for medical monitoring

Abstract: A wireless, programmable system for bio-potential signal acquisition (e.g., electrocardiogram (ECG) data) includes a base unit and a plurality of individual wireless, remotely programmable transceivers that connect to patch electrodes. The base unit manages the transceivers by issuing registration, configuration, data acquisition, and transmission commands using wireless techniques. Bio-potential signals from the wireless transceivers are demultiplexed and supplied via a standard interface to a conventional monitor for display.

Connectors for hollow anatomical structures and methods of use

Abstract: The connector consists of an annular rigid body conformed to an outer surface around a wall-opening of a hollow anatomical structure and holding means that keep the hollow structure adjoined internally to the annular body, wherein a union of the annular body with another annular body of another connector attached to another hollow structure forms an inner fluidproof surface that surrounds the abutted cut-edges of the wall-openings of the approximated two hollow structures. Different embodiments of end connectors and side connectors in divisible or indivisible unions are provided for end-to-end and side-to-end anastomoses of various hollow structures.

Self configuring multiple element portable electronic device

Abstract: A self configuring multiple element portable electronic device (100) and method is provided. The device comprises at least a first electronic element (104) and a second electronic element (106) and a joint (112) connecting the first electronic element and the second electronic element, with the joint allowing movement in more than one plane of the first electronic element in relation to the second electronic element, wherein the self configuring multiple element portable electronic device is capable of self configuring an operational mode based on a relative position of the first electronic element with respect to the second electronic element. The method comprises the steps of detecting a relative position of the first electronic element relative to the second electronic element, and selecting an operational mode of the device based on the relative position.

A TOA-based location algorithm reducing the errors due to non-line-of-sight (NLOS) propagation

Abstract: An effective location algorithm, which considers non-line-of-sight (NLOS) propagation, is presented. By using a new variable to replace the square term and adding the loose variable, the problem becomes a mathematical programming problem, and then the NLOS propagation's effect can be evaluated. This method is simple and does not add much computation time. Compared with other methods, it has high accuracy.

Method and apparatus for transferring a communication session

Abstract: Session Inter-Device (SID) mobility networks (50, 100, 150) are described in which a seamless transfer of a communication session from a first device (56. 106, 116) to a second device (66, 116, 166) can be achieved without interrupting the active session. According to the SID mobility network (50), the transfer can be accomplished by transferring away from the Transferring Node or first device (56) the IP address associated with the active session (58) so that the network (50) will route the session to the desired Target Node or second device (66). The Transferring Node (56) transfers its IP address (58) to the Agent (60) and stops requesting data packets addressed to its IP address (58). The Agent (60) then begins to request and eventually receive the packets addressed to the Transferring Node's IP address (58). The Agent (60) then transfers the packets to the Target Node (66). In an alternate SID mobility network (100), the Transferring Node (106) transfers a session specific IP address (114) to the Agent (110). The Agent (110) then transfers packets sent to the session specific IP address (114) to the Target Node (120). In another SID mobility network (150), the Transferring Node (162) obtains a temporary IP address (170) and transfers its IP address (164) to a Session Agent (166). The Session Agent (166) begins to request and eventually receive the packets addressed to the Transferring Node's IP address (164), and for each received packet determines if it belongs to the session the Transferring Node (162) requested to transfer to the Target Node (176). If it does, the Session Agent (166) will transfer the packet to the Target Node (176) at the Target Node's IP address (178). If it does not, the Session Agent (166) will transfer the packet to the Transferring Node (162) at its temporary IP address (170). In each SID mobility network, the session with respect to the Correspondent Node continues without interruption throughout the transfer, thereby providing a seamless transfer of the session from a first device to a second device.

Method for forming a high dielectric constant material

Abstract: Highe quality silicon oxide having a plurality of monolayers is grown at a high temperature on a silicon substrate. A monolayer of silicon oxide is a single layer of silicon atoms and two oxygen atoms per silicon atom bonded thereto. The silicon oxide is etched one monolayer at a time until a desired thickness of the silicon layer is obtained. Each monolayer is removed by introducing a first gas to form a reaction layer on the silicon oxide. The gas is then purged. Then the reaction layer is activated by either another gas or heat. The reaction layer then acts to remove a single monolayer. This process is repeated until a desired amount of silicon oxide layer remains. Because this removal process is limited to removing one monolayer at a time, the removal of silicon oxide is well controlled. This allows for a precise amount of silicon oxide to remain.

A controlled experiment in maintenance: comparing design patterns to simpler solutions

Abstract: Software design patterns package proven solutions to recurring design problems in a form that simplifies reuse. We are seeking empirical evidence whether using design patterns is beneficial. In particular, one may prefer using a design pattern even if the actual design problem is simpler than that solved by the pattern, i.e., if not all of the functionality offered by the pattern is actually required. Our experiment investigates software maintenance scenarios that employ various design patterns and compares designs with patterns to simpler alternatives. The subjects were professional software engineers. In most of our nine maintenance tasks, we found positive effects from using a design pattern: either its inherent additional flexibility was achieved without requiring more maintenance time or maintenance time was reduced compared to the simpler alternative. In a few cases, we found negative effects: the alternative solution was less error-prone or required less maintenance time. Overall, we conclude that, unless there is a clear reason to prefer the simpler solution, it is probably wise to choose the flexibility provided by the design pattern because unexpected new requirements often appear. We identify several questions for future empirical research.

Microfabricated polycarbonate CE devices for DNA analysis.

Abstract: The microchip capillary electrophoresis (CE) devices were fabricated in polycarbonate (PC) plastic material by compression molding. The molded devices were enclosed utilizing thermal bonding to another PC wafer. These thermal bonds do not yield up to an applied force equivalent to 150 psi. Aqueous fluid transport inside the plastic CE devices was enhanced by UV irradiation treatment of the hydrophobic polycarbonate plastic surfaces prior to thermal bonding. In comparison to glass microchannels, electroosmotic flow (EOF) in native PC channels is low and is independent of buffer pH at pH 7 and 9. UV irradiation of PC surfaces increases surface hydrophilicity and increases EOF. CE DNA separation was demonstrated in these PC CE devices with good resolution and run-to-run reproducibility. The on-chip PCR/CE analysis of a 500-bp region of bacteriophage λ DNA was also demonstrated.