Showing papers by "Qualcomm published in 2009"

IEEE 802.22: The first cognitive radio wireless regional area network standard

Abstract: This article presents a high-level overview of the IEEE 802.22 standard for cognitive wireless regional area networks (WRANs) that is under development in the IEEE 802 LAN/MAN Standards Committee.

Packaging and details of a wireless power device

Abstract: A wireless power system includes a power source, power receiver, and components thereof. The system can also include a parasitic antenna that can improve the coupling to the power source in various modes. The antenna can have both a variable capacitor and a variable inductor, and both of those can be changed in order to change characteristics of the matching.

Cooperative Communications and Networking

Abstract: Presenting the fundamentals of cooperative communications and networking, this book treats the concepts of space, time, frequency diversity and MIMO, with a holistic approach to principal topics where significant improvements can be obtained. Beginning with background and MIMO systems, Part I includes a review of basic principles of wireless communications and space-time diversity and coding. Part II then presents topics on physical layer cooperative communications such as relay channels and protocols, performance bounds, multi-node cooperation, and energy efficiency. Finally, Part III focuses on cooperative networking including cooperative and content-aware multiple access, distributed routing, source-channel coding, and cooperative OFDM. Including end-of-chapter review questions, this text will appeal to graduate students of electrical engineering and is an ideal textbook for advanced courses on wireless communications. It will also be of great interest to practitioners in the wireless communications industry. Presentation slides for each chapter and instructor-only solutions are available at www.cambridge.org/9780521895132.

Cognitive Radio: An Information-Theoretic Perspective

Abstract: In this paper, we consider a communication scenario in which the primary and the cognitive radios wish to communicate to different receivers, subject to mutual interference. In the model that we use, the cognitive radio has noncausal knowledge of the primary radio's codeword. We characterize the largest rate at which the cognitive radio can reliably communicate under the constraint that 1) no rate degradation is created for the primary user, and 2) the primary receiver uses a single-user decoder just as it would in the absence of the cognitive radio. The result holds in a ldquolow-interferencerdquo regime in which the cognitive radio is closer to its receiver than to the primary receiver. In this regime, our results are subsumed by the results derived in a concurrent and independent work (Wu , 2007). We also demonstrate that, in a ldquohigh-interferencerdquo regime, multiuser decoding at the primary receiver is optimal from the standpoint of maximal jointly achievable rates for the primary and cognitive users.

Multi-media broadcast and multicast service (MBMS) in a wireless communication system

Abstract: Techniques to implement MBMS services in a wireless communication system. In one aspect, a method is provided for processing data for transmission to a plurality of terminals. Frames of information bits (which may have variable rates) are provided to a buffer implementing a matrix. The matrix is padded with padding bits based on a particular padding scheme to support variable frame rates. The frames are then coded based on a particular block code to provide parity bits. The frame of information bits and the parity bits are then transmitted to the terminals. In another aspect, a method is provided for controlling the transmit power of a data transmission to a plurality of terminals. In accordance with the method, TPC streams are received from the terminals and processed to obtain a stream of joint power control commands used to adjust the transmit power of the data transmission.

Wireless power transmission for electronic devices

Abstract: Exemplary embodiments are directed to wireless power transfer. A wireless power receiver includes a receive antenna for coupling with a transmit antenna of transmitter generating a magnetic near field. The receive antenna receives wireless power from the magnetic near field and includes a resonant tank and a parasitic resonant tank wirelessly coupled to the resonant tank. A wireless power transmitter includes a transmit antenna for coupling with a receive antenna of a receiver. The transmit antenna generates a magnetic near field for transmission of wireless power and includes a resonant tank and a parasitic resonant tank coupled to the resonant tank.

Method and apparatus for adaptive tuning of wireless power transfer

Abstract: Exemplary embodiments are directed to wireless power transfer. A transmit antenna generates an electromagnetic field at a resonant frequency of to create a coupling-mode region within a near field of the transmit antenna. A receive antenna receives the resonant frequency when it is within the coupling-mode region and resonates substantially near the resonant frequency. One, or both, of the transmit and receive antennas are tunable antennas that can be adaptively tuned. The adaptive tuning is accomplished by detecting a mismatch at the tunable antenna and generating a mismatch signal responsive to a voltage standing wave ratio at the tunable antenna. A resonance characteristic of the tunable antenna can be modified by adjusting a capacitance of a variable capacitor network connected to the tunable antenna.

Multi-panel electronic device

Abstract: Methods, apparatuses, and computer-readable storage media for displaying an image at an electronic device are disclosed. In a particular embodiment, a method includes displaying an image at an electronic device that includes a first display surface and a second display surface separated from the first display surface by a gap. A first portion of the image is displayed at the first display surface, a second portion of the image is displayed at the second display surface, and a third portion of the image between the first portion and the second is not displayed. A movement of the electronic device is detected, and in response to detecting the movement, the third portion of the image is displayed at the second display surface.

Wireless power transmission for portable wireless power charging

Abstract: Exemplary embodiments are directed to wireless power transfer. A portable wireless power charger includes an antenna configured to generate a magnetic near-field for coupling of wireless power to a wireless powered device including a receiver. The antenna is substantially disposed around the perimeter of the charging pad. The portable wireless power charger further includes a feeder cable for coupling the input power to the charging pad.

Wireless power transfer for vehicles

Abstract: Exemplary embodiments are directed to wireless power transfer. A power transmitting device is attached to an existing vehicle item or is embedded in a vehicle element. The power transmitting device includes a transmit antenna to wirelessly transfer power to a receive antenna by generating a near-field radiation within a coupling-mode region. An amplifier applies a driving signal to the transmit antenna. A presence detector may detect a presence of a receiver device within the coupling-mode region. The presence detector may also detect a human presence. An enclosed compartment detector may detect when the vehicle element is in a closed state. A power output may be adjusted in response to the closed state, the presence of a receiver device, and the presence of a human.

Wireless power for charging devices

Abstract: Exemplary embodiments are directed to wireless power. A host device peripheral may comprise a wireless power charging apparatus, which may include transmit circuitry and at least one antenna coupled to the transmit circuitry. The at least one antenna may be configured to wirelessly transmit power within an associated near-field region. Additionally, the host device peripheral may be configured to couple to a host device.

Bidirectional wireless power transmission

Abstract: Exemplary embodiments are directed to wireless power transfer. A wireless power transceiver and device comprise an antenna including a parallel resonator configured to resonate in response to a substantially unmodulated carrier frequency. The wireless power transceiver further comprises a bidirectional power conversion circuit coupled to the parallel resonator. The bidirectional power conversion circuit is reconfigurable to rectify an induced current received at the antenna into DC power and to induce resonance at the antenna in response to DC power.

Method and apparatus for aggregating and presenting data associated with geographic locations

Abstract: Implementations relate to systems and methods for aggregating and presenting data related to geographic locations. Geotag data related to geographic locations and associated features or attributes can be collected to build a regional profile characterizing a set of locations within the region. Geotag data related to the constituent locations, such as user ratings or popularity ranks for restaurants, shops, parks, or other features, sites, or attractions, can be combined to generate a profile of characteristics of locations in the region. The platform can generate recommendations of locations to transmit to the user of a mobile device, based for instance on the location of the device in the region as reported by GPS or other location service and the regional profile. Geotag data can include audio data analyzed using region-specific terms, and user recommendations can be presented via dynamic menus based on regional profiles, user preferences or other criteria.

Wireless power transfer in public places

Abstract: Exemplary embodiments are directed to public wireless-power-transmission. A device disposed in or on a publicly placed structure and a user neighboring device includes a repeater antenna with a loop antenna and a capacitive element. The public wireless-power-transmitting device includes a transmit antenna to wirelessly transfer power by generating a near-field radiation at a resonant frequency within a coupling-mode region and an amplifier for driving the transmit antenna. When in the coupling-mode region, the repeater antenna couples with the near-field radiation generated by the transmit antenna and develops an enhanced coupling-mode region about the repeater antenna with a repeated near-field radiation that is stronger than the near-field radiation of the transmit antenna within the enhanced coupling-mode region. Power may be wirelessly transferred from the enhanced coupling-mode region to a receiver device including a receive antenna.

Systems and methods relating to multi-dimensional wireless charging

Abstract: Exemplary methods and systems related to wireless charging are disclosed. In an exemplary embodiment, a plurality of transmit antennas are used, wherein at least one transmit antenna of the plurality of transmit antennas is configured to be oriented in a different plane than at least one other transmit antenna of the plurality of transmit antennas. Furthermore, each transmit antenna of the plurality of transmit antennas is configured for transmitting power within an associated near-field.

Adder and Multiplier Design in Quantum-Dot Cellular Automata

Abstract: Quantum-dot cellular automata (QCA) is an emerging nanotechnology, with the potential for faster speed, smaller size, and lower power consumption than transistor-based technology. Quantum-dot cellular automata has a simple cell as the basic element. The cell is used as a building block to construct gates and wires. Previously, adder designs based on conventional designs were examined for implementation with QCA technology. That work demonstrated that the design trade-offs are very different in QCA. This paper utilizes the unique QCA characteristics to design a carry flow adder that is fast and efficient. Simulations indicate very attractive performance (i.e., complexity, area, and delay). This paper also explores the design of serial parallel multipliers. A serial parallel multiplier is designed and simulated with several different operand sizes.

45nm low power CMOS logic compatible embedded STT MRAM utilizing a reverse-connection 1T/1MTJ cell

Abstract: This paper reports a 45nm spin-transfer-torque (STT) MRAM embedded into a standard CMOS logic platform that employs low-power (LP) transistors and Cu/low-k BEOL. We believe that this is the first-ever demonstration of embedded STT MRAM that is fully compatible with the 45nm logic technology. To ensure the switching margin, a novel Ȝreverse-connectionȝ 1T/1MT cell has been developed with a cell size of 0.1026 µm2. This cell is utilized to build embedded memory macros up to 32 Mbits in density. Device attributes and design windows have been examined by considering PVT variations to secure operating margins. Promising early reliability data on endurance, read disturb, and thermal stability have been obtained.

Tracking receiver devices with wireless power systems, apparatuses, and methods

Abstract: Exemplary embodiments are directed to communicating information relating to wireless charging. A power transmitting system includes a host device with a transmit antenna. A communication interface conveys receiver information, which includes unique identifier information, from a receiver device to the host device. A controller on the host device monitors and processes the receiver information to generate notification information, which is presented to a user on a user-perceivable notifier. The transmit antenna generates an electromagnetic field at a resonant frequency to create a coupling-mode region within a near-field of the transmit antenna. The system can detect a presence of a receiver device with a receive antenna that is in the coupling-mode region and process a request for power from the receiver device. The system can also notify a user when a host device is leaving a designated region and whether the host device includes expected receiver devices.

Reduced jamming between receivers and wireless power transmitters

Abstract: Exemplary embodiments are directed to reducing jamming caused by radiated fields generated by wireless power transmitters. Exemplary embodiments include detecting a jamming condition of a wireless power receiving device resulting from a radiated field from a wireless power transmitter of a charging device. Such embodiments include synchronizing the wireless power coupling with communication of the wireless power receiving device. Synchronizing wireless power coupling may include wireless power coupling at a first level when the wireless power receiving device is expected to receive a signal on a communication channel. Synchronizing wireless power coupling may further include coupling at a higher rate when the wireless power receiving device is not expected to receive a signal on the communication channel.

Tuning in to RF MEMS

Abstract: RF MEMS technology was initially developed as a replacement for GaAs HEMT switches and p-i-n diodes for low-loss switching networks and X-band to mm-wave phase shifters. However, we have found that its very low loss properties (high device Q), its simple microwave circuit model and zero power consumption, its high power (voltage/current) handling capabilities, and its very low distortion properties, all make it the ideal tuning device for reconfigurable filters, antennas and impedance matching networks. In fact, reconfigurable networks are currently being funded at the same level-if not higher-than RF MEMS phase shifters, and in our opinion, are much more challenging for high-Q designs.

Interference management and performance analysis of UMTS/HSPA+ femtocells

Abstract: Femtocells are low-power cellular base stations that operate in licensed spectrum. They are typically deployed indoors to improve coverage and provide excellent user experience, including high data rates. Cellular operators benefit from reduced infrastructure and operational expenses for capacity upgrades and coverage improvements. Femtocells also bring unique challenges, such as unplanned deployment, user installation, restricted access, and interoperability with existing handsets and network infrastructure. Although femtocells may cause some interference to other users in the network, with the use of proper interference management techniques, this can be well controlled. We present interference management techniques for both downlink and uplink of femtocells operating based on 3GPP Release 7 standards (also known as HSPA+). Femtocell carrier selection and femtocell DL Tx power self-calibration are proposed as key interference management methods for downlink. For uplink interference management, adaptive attenuation at the femtocell and limiting the Tx power of the femtocell users are proposed. Different interference models and their analysis are presented. In addition, coverage performance and capacity results are presented to quantify the benefits of femtocells. We demonstrate that in addition to coverage enhancements, significant capacity improvements are achieved on both downlink and uplink when femtocells are deployed in 3G UMTS/HSPA+ networks.

Multi-fold mobile device with configurable interface

Abstract: A multi-fold mobile device with a configurable interface is disclosed. In a particular embodiment, a method includes detecting a hardware configuration change from a first configuration to a second configuration at an electronic device that includes at least a first panel having a first display surface and a second panel having a second display surface. The hardware configuration change includes a change in a relative orientation of the first display panel to the second display panel. The method also includes automatically modifying a graphical user interface displayed at the first display surface and the second display surface at least partially based on the second configuration.

Card metaphor for activities in a computing device

Abstract: In various embodiments, a card metaphor is established, in which each activity can be represented within an area of the screen referred to as a card. In various embodiments, any of several display modes are available for viewing, interacting with, manipulating, initiating, and dismissing cards. A persistent positional relationship can be established among cards, represented by a one-dimensional sequence. Newly opened cards are generally placed at the end of the sequence, although a new card that bears a relationship to an already open card may, in some embodiments, be placed adjacent to the already open card. In various embodiments, cards may be grouped, with such groups being represented as stacks of cards or by other visually distinctive means.

Wireless high power transfer under regulatory constraints

Abstract: Improved battery-charging system for a vehicle. Primary and secondary coils are located in places where the vehicle can receive power from the primary coil by pulling into a parking space, for example. The parking space may have a coil embedded in the ground, or may have an array of coils embedded in the ground. A guidance system is disclosed. Fine positioning is also disclosed. The secondary coil in the vehicle can also be raised or lowered to improve coupling.

Receive antenna arrangement for wireless power

Abstract: Exemplary embodiments are directed to wireless charging. An electronic device may comprise at least one receive antenna integrated within an electronic device and configured to receive wireless power from a wireless transmit antenna. Further, the at least one receive antenna may be spaced from each conductive component within the electronic device having a clearance therebetween adapted to enable formation of a magnetic field around the loop conductor.

Video coding with large macroblocks

Abstract: Techniques are described for encoding and decoding digital video data using macroblocks that are larger than the macroblocks prescribed by conventional video encoding and decoding standards. For example, the techniques include encoding and decoding a video stream using macroblocks comprising greater than 16×16 pixels. In one example, an apparatus includes a video encoder configured to encode a coded unit comprising a plurality of video blocks, wherein at least one of the plurality of video blocks comprises a size of more than 16×16 pixels and to generate syntax information for the coded unit that includes a maximum size value, wherein the maximum size value indicates a size of a largest one of the plurality of video blocks in the coded unit. The syntax information may also include a minimum size value. In this manner, the encoder may indicate to a decoder the proper syntax decoder to apply to the coded unit.

Centralized control of peer discovery pilot transmission

Abstract: Techniques for centralized control of peer discovery pilot transmission are described. In an aspect, a designated network entity (e.g., a base station or a network controller) may control transmission of peer discovery pilots by stations located within its coverage area. In one design, the network entity may receive signaling triggering peer discovery pilot transmission. The network entity may direct each of at least one station to transmit a peer discovery pilot to allow one or more stations to detect the at least one station. The peer discovery pilot may include at least one synchronization signal or at least one reference signal. The network entity may receive pilot measurements from the one or more stations for peer discovery pilots from peer stations and/or reference signals from base stations. The network entity may determine whether or not to select peer-to-peer communication for two stations based on the pilot measurements.

A 52 $\mu$ W Wake-Up Receiver With $-$ 72 dBm Sensitivity Using an Uncertain-IF Architecture

Abstract: A dedicated wake-up receiver may be used in wireless sensor nodes to control duty cycle and reduce network latency. However, its power dissipation must be extremely low to minimize the power consumption of the overall link. This paper describes the design of a 2 GHz receiver using a novel ldquouncertain-IFrdquo architecture, which combines MEMS-based high-Q filtering and a free-running CMOS ring oscillator as the RF LO. The receiver prototype, implemented in 90 nm CMOS technology, achieves a sensitivity of -72 dBm at 100 kbps (10-3 bit error rate) while consuming just 52 muW from the 0.5 V supply.

Multi-panel device with configurable interface

Abstract: A multi-panel device is disclosed. In a particular embodiment, the device includes a first hinge coupled to a first panel and coupled to a second panel. The first panel includes a first display surface and the second panel includes a second display surface. The second hinge is coupled to the second panel and coupled to a third panel that includes a third display surface. The device also includes a sensor coupled to the first hinge to detect a relative orientation of the first panel to the second panel. The device includes a processor responsive to the sensor to detect a device configuration. The processor is configured to adjust a user interface displayed at the first display surface, the second display surface, and the third display surface based on the detected device configuration.

Wireless position determination using adjusted round trip time measurements

Abstract: One method for wirelessly determining a position of a mobile station includes measuring a round trip time (RTT) to a plurality of wireless access points, estimating a first distance to each wireless access point based upon the round trip time delay and an initial processing time associated with each wireless access point, estimating a second distance to each wireless access point based upon supplemental information, combining the first and second distance estimates to each wireless access point, and calculating the position based upon the combined distance estimates. Another method includes measuring a distance to each wireless access point based upon a wireless signal model, calculating a position of the mobile station based upon the measured distance, determining a computed distance to each wireless access point based upon the calculated position of the mobile station, updating the wireless signal model, and determining whether the wireless signal model has converged.