Patent application number | Description | Published |
20080232389 | Distributed Overlay Multi-Channel Media Access Control for Wireless Ad Hoc Networks - Systems and methods for distributed overlay multi-channel MAC for wireless ad hoc networks are described. In one aspect, the systems and methods divide channel frequencies defined by a wireless network protocol into a single home channel and multiple guest channels that are orthogonal to the home channel. Each of the network nodes in the ad hoc network operates on the home channel for respective variable and overlapping amounts of time to maintain network connectivity with other respective network nodes. Additionally, each of the network nodes determines whether and when to switch from the home channel to a particular guest channel of the guest channels for a variable amount of time to increase data throughput over one or more corresponding communication links in the ad hoc network with other network node(s). | 09-25-2008 |
20080279092 | Channel control based on error correction values - A computing device configured for wireless communication may effectively control adaptation to channel conditions. The device may be configured to identify and classify conditions impacting performance of a channel so that appropriate adaptations may be made. Interference may be detected by correlating received signal strength and packet errors. High received signal strength correlated to a high packet error rate may signify presence of a source of interference. Once a source of interference is detected, other criteria may be used to determine the nature of the interference so that an adaptation that is minimally disruptive of applications can be selected. Additionally, channel degradation may be predicted by monitoring trends in error rates, including Forward Error Correction rates, and adaptation may be used before packet error rates exceed an unacceptable level. | 11-13-2008 |
20080279093 | Interference detection - A computing device configured for wireless communication may effectively control adaptation to channel conditions. The device may be configured to identify and classify conditions impacting performance of a channel so that appropriate adaptations may be made. Interference may be detected by correlating received signal strength and packet errors. High received signal strength correlated to a high packet error rate may signify presence of a source of interference. Once a source of interference is detected, other criteria may be used to determine the nature of the interference so that an adaptation that is minimally disruptive of applications can be selected. Additionally, channel degradation may be predicted by monitoring trends in error rates, including Forward Error Correction rates, and adaptation may be used before packet error rates exceed an unacceptable level. | 11-13-2008 |
20080304361 | Acoustic Ranging - Acoustic ranging may involve determining a distance between a first device and at least one other device using one or more acoustic signals. In an example embodiment, a first device emits a first acoustic signal and then receives the first acoustic signal at a first time. The first device also receives a second acoustic signal at a second time, with the second acoustic signal having been emitted by a second device. The first device ascertains a first value that reflects a difference between the first time and the second time. Responsive to at least the ascertained first value, the first device determines a distance between the first device and the second device. | 12-11-2008 |
20090046603 | PATH DISCOVERY AND MESSAGE TRANSFER IN PARTIALLY CONNECTED MOBILE AD HOC NETWORKS - A method and system is presented for path discovery and asynchronous message transfer in a partially connected middleware communication space comprising mobile ad hoc networks. Embodiments of the present invention use mobile devices to bridge separated islands of networks and store and propagate messages. The system and software architecture supports methods for routing, messaging caching, and transferring. More specifically, embodiments provide methods and systems that extend a communication space concept into a distributed environment and combine it with the standard Web Services technologies, i.e., SOAP, and WS series protocols. The communication space provides an extension of Web Services to mobile ad hoc networks and provides asynchronous message caching, transferring and routing. | 02-19-2009 |
20090103461 | HIERARCHICAL APPLICATION PROGRAMMING INTERFACE FOR COMMUNICATION MIDDLEWARE IN PARTIALLY CONNECTED MOBILE AD HOC NETWORKS - An application programming interface and related system is presented for a middleware communication space that provides asynchronous message delivery service for partially connected mobile ad hoc networks. Embodiments of the present invention use mobile devices to bridge separated islands of networks and store and propagate messages. The system and software architecture supports methods for messaging caching, transferring and routing. More specifically, embodiments provide methods and systems that extend a communication space concept into a distributed environment and combine it with the standard Web Services technologies, i.e, SOAP, and WS series protocols. The communication space provides an extension of Web Services to mobile ad hoc networks and provides asynchronous message caching, transferring and routing. | 04-23-2009 |
20090122700 | Spectrum and medium access allocation for fairness - Each node or link of an ad hoc network assists in the distributed allocation of a data channel to increase fairness, even in a multi-hop network, by tracking a measure of link weight for itself and sharing this information over a control channel with neighboring nodes. The metric can be provided over a dedicated control channel, added as a header to data communication on a data channel, or inferred by monitoring data traffic from the neighboring node. The link weight can be adjusted by a link quality factor based on provided or inferred metrics such as transmission rates, ratio of transmission errors, idle time, etc. For multiple flow queues at a subject node, one with a higher transmission rate can be selected for increased fairness. When a packet is received, medium access includes allocating bandwidth, including bonding multiple frequencies that are determined to be available to both nodes. | 05-14-2009 |
20090124205 | PHYSICAL AND MAC ADAPTATION FOR INTERFERENCE MITIGATION WITH COGNITIVE RADIO - A communication device cognitively monitors interference signals across a communication band so that adaptations for physical and medium access control (MAC) of data packet transmissions are appropriate for a particular interference signal. Characteristics of an interference signal of interest (e.g., bandwidth, power and/or duration relative to an average data packet transmitted over a communication channel of the communication device) are sensed for an appropriate adaptation (e.g., forward error correction, modulation technique, back off, request to send/clear to send protocol, etc.). Patterns for known types of interference sources can be compared so that when recognized an associated adaptation can be used. | 05-14-2009 |
20090175182 | Differentiated service transmission parameters adaptation - Systems and methods are provided for transmitting data on a wireless network. Some embodiments provide a technique whereby a type is determined for the transmission, at least one metric is determined for the transmission based at least in part on the transmission type and/or an indication of conditions on the channel on which the transmission is to be performed, at least one transmission parameter to be used in performing the transmission is selected to optimize the at least one metric, and the data is transmitted in accordance with the at least one transmission parameter. | 07-09-2009 |
20090274043 | MULTI-LEVEL INTERCONNECTION NETWORK - A method and system for providing a multi-level interconnection network is provided. A multi-level interconnection network comprises basic cells that are aggregated into higher level cells at each level of the network. At the first level, the basic cells are aggregated into first level cells. Each first level cell is an aggregation of a number of basic cells that is one more than the number of devices in a basic cell. The basic cells of a first level cell are fully connected; that is, each basic cell has a first level link or connection to each other basic cell. In a first level cell, each device of a basic cell has a first level link to each other basic cell. The multi-level interconnection network has higher level cells that are aggregations of lower level cells in a similar manner. | 11-05-2009 |
20090274063 | MULTI-LEVEL INTERCONNECTION NETWORK - A method and system for providing a multi-level interconnection network is provided. A multi-level interconnection network comprises basic cells that are aggregated into higher level cells at each level of the network. At the first level, the basic cells are aggregated into first level cells. Each first level cell is an aggregation of a number of basic cells that is one more than the number of devices in a basic cell. The basic cells of a first level cell are fully connected; that is, each basic cell has a first level link or connection to each other basic cell. In a first level cell, each device of a basic cell has a first level link to each other basic cell. The multi-level interconnection network has higher level cells that are aggregations of lower level cells in a similar manner. | 11-05-2009 |
20100153523 | SCALABLE INTERCONNECTION OF DATA CENTER SERVERS USING TWO PORTS - Large numbers of commodity servers in a data center may be inexpensively interconnected using low-cost commodity network switches, a first network port on each commodity server, a second network port on each commodity server, and a traffic-aware routing module executed on each commodity server. Connecting two or more commodity servers via the first network ports on each server to a commodity network switch forms a unit. Connecting two commodity servers in different units forms a group. Each unit has a direct connection via a second network port on a commodity server in the unit to another unit. Each group may have a direct connection via a second network port on a commodity server in the group to another group. Traffic-aware routing modules executed on each commodity server determine routing of data between servers and balance traffic across the first and second ports. | 06-17-2010 |
20100172274 | Energy saving using cellular footprint for mobile device Wi-Fi access point discovery - Described is a technology in which a Wi-Fi enabled mobile computing device conserves power by only selectively scanning to discover a potential access point for connecting. In one aspect, a cellular footprint, comprising the cellular tower identifier(s) and corresponding signal strength information, determines whether to perform or delay the Wi-Fi scan. The footprint may be used to detect mobile user location changes and compare with history, so as to delay scanning when the device has not sufficiently moved, or delay scanning when the history indicates little chance of a successful discovery/connection at the current location. | 07-08-2010 |
20100172275 | Energy Efficient Device Discovery with Short-Range Radios - Described is a technology in which a Wi-Fi enabled mobile computing device conserves power by only attempting peer discovery at certain times, according to a wakeup pattern. A device time clock is synchronized, such as via a cellular service, a GPS system, or a network to establish the time to awaken. Imprecise synchronization between the devices within a maximum difference is acceptable because the pattern ensures that any two devices are concurrently awake for at least a sufficient time to perform discovery. The awake time may be divided into active and inactive slots, arranged such that an active slot of each device will overlap regardless of when the awake time begins on each device. Also described is using a previously agreed-upon communications channel for subsequent discovery, which may be based upon pseudo-random number generation. | 07-08-2010 |
20100214945 | Distributed Overlay Multi-Channel Media Access Control (MAC) for Wireless Ad Hoc Networks - Systems and methods for distributed overlay multi-channel MAC for wireless ad hoc networks are described. In one aspect, the systems and methods divide channel frequencies defined by a wireless network protocol into a single home channel and multiple guest channels that are orthogonal to the home channel. Each of the network nodes in the ad hoc network operates on the home channel for respective variable and overlapping amounts of time to maintain network connectivity with other respective network nodes. Additionally, each of the network nodes determines whether and when to switch from the home channel to a particular guest channel of the guest channels for a variable amount of time to increase data throughput over one or more corresponding communication links in the ad hoc network with other network node(s). | 08-26-2010 |
20110035522 | Software-Defined Radio Using Multi-Core Processor - A radio control board passes a plurality of digital samples between a memory of a computing device and a radio frequency (RF) transceiver coupled to a system bus of the computing device. Processing of the digital samples is carried out one or more cores of a multi-core processor to implement a software-defined radio. | 02-10-2011 |
20110078355 | Radio-Control Board For Software-Defined Radio Platform - A radio control board exchanges data with a radio frequency (RF) front end using a messaging protocol over an interface that includes separate data and control channels. Training data can also be passed over the interface for tuning the clock phase. | 03-31-2011 |
20110103262 | MULTI-LEVEL INTERCONNECTION NETWORK - A method and system for providing a multi-level interconnection network is provided. A multi-level interconnection network comprises basic cells that are aggregated into higher level cells at each level of the network. At the first level, the basic cells are aggregated into first level cells. Each first level cell is an aggregation of a number of basic cells that is one more than the number of devices in a basic cell. The basic cells of a first level cell are fully connected; that is, each basic cell has a first level link or connection to each other basic cell. In a first level cell, each device of a basic cell has a first level link to each other basic cell. The multi-level interconnection network has higher level cells that are aggregations of lower level cells in a similar manner. | 05-05-2011 |
20110136439 | Analyzing Wireless Technologies Based On Software-Defined Radio - An analysis application is adapted to be executed on a computing device for collecting data for analysis from a software-defined radio implemented on the same computing device or on a separate computing device for testing measurement and analysis of wireless standards, radio configurations, communication protocols and other radio technologies. | 06-09-2011 |
20110138259 | High Performance Digital Signal Processing In Software Radios - An extensive use of look-up table (LUT) and single instruction multiple data (SIMD) in different algorithms in a software-defined radio (SDR) system is described. In particular, the LUT is used during spreading modulation, mapping and spreading, scrambling, de-scrambling, soft demapping, and the like. The SIMD is executed by a multi-core processor during implementation of a “min” operation to find an optimal path in a Trellis diagram for a Viterbi decoder. | 06-09-2011 |
20110299612 | UNCONTROLLED SPATIAL MULTIPLE ACCESS IN WIRELESS NETWORKS - An uncontrolled spatial multiple access system and method facilitating spatial multiple access for multiple devices in a wireless local-area network (WLAN). Embodiments of the system and method increase throughput of the wireless network by facilitating concurrent encoded frame transmission. Decoding of the quasi-overlapped frames is achieved using a chain decoding technique that takes data streams (or signals) containing the quasi-overlapping encoded frames and isolates each encoded frame so that the frame can be decoded. Quasi-overlapped frames means that the frames are overlapped in the body of the frame but not at the preamble (or headers) of the frames. Embodiments of the chain decoding also use interference nullifying and interference cancelation to enable concurrent quasi-overlapping transmission. A carrier counting multiple access technique of embodiments of the system and method allow wireless networks to retain their asynchronous nature while supporting spatial multiple access and maintain backwards compatibility with the IEEE 802.11 standard. | 12-08-2011 |
20110317633 | FINE-GRAINED CHANNEL ACCESS IN WIRELESS NETWORKS - A fine-grained channel access system and method to facilitate fine-grained channel access in a high-data rate wide-band wireless local-area network (WLAN). Embodiments of the system and method divide an entire wireless channel into proper size subchannels commensurate with the physical layer data rate and typical frame size. Once the subchannels are defined, each node on the WLAN contends independently for each of the fine-grained subchannels. A first orthogonal frequency-division multiplexing (OFDM) technique is used to signal an access point on the WLAN that the node desires one or more of the subchannels. A second OFDM technique (which is different from the first OFDM technique) is used for data transmission. Sometimes there is contention between nodes that want the same subchannel. The access point resolves any contention between the nodes using a frequency domain contention technique that includes a frequency domain backoff technique. | 12-29-2011 |
20120121030 | Compressive Wireless Modulation - A projection code is applied to encode symbols as weighted arithmetic sums of approximately random subsets of binary source bits. Pairs of the symbols are combined to form constellation points, which are sequentially mapped through a constellation to modulate a data signal. | 05-17-2012 |
20120127914 | Full-Rate Cooperative Relay - Techniques and systems that improve throughput between a pair of nodes by using two multi-hop paths of one-way flows regardless of the one-way flows interfering with each other are described herein. These techniques enable nearly full-rate data flow through frame transmissions, even though these frame transmissions can interfere with substantially concurrent relay transmissions. In some implementations, relays on the two paths forward mixed frame signals to the next hop without trying to decode the mixed frame signals of interfered frames. The destination successfully recovers the useful information from the mixed frame signals by canceling out interference based on previously received frames. | 05-24-2012 |
20130039211 | INTERFERENCE DETECTION - A computing device configured for wireless communication may effectively control adaptation to channel conditions. The device may be configured to identify and classify conditions impacting performance of a channel so that appropriate adaptations may be made. Interference may be detected by correlating received signal strength and packet errors. High received signal strength correlated to a high packet error rate may signify presence of a source of interference. Once a source of interference is detected, other criteria may be used to determine the nature of the interference so that an adaptation that is minimally disruptive of applications can be selected. Additionally, channel degradation may be predicted by monitoring trends in error rates, including Forward Error Correction rates, and adaptation may be used before packet error rates exceed an unacceptable level. | 02-14-2013 |
20130121257 | Mapping Signals from a Virtual Frequency Band to Physical Frequency Bands - Embodiments include processes, systems, and devices for reshaping virtual baseband signals for transmission on non-contiguous and variable portions of a physical baseband, such as a white space frequency band. In the transmission path, a spectrum virtualization layer maps a plurality of frequency components derived from a transmission symbol produced by a physical layer protocol to sub-carriers of the allocated physical frequency band. The spectrum virtualization layer then outputs a time-domain signal derived from the mapped frequency components. In the receive path, a time-domain signal received on the physical baseband is reshaped by the virtual spectrum layer in order to recompose a time-domain symbol in the virtual baseband. | 05-16-2013 |
20130122949 | Mapping a Transmission Stream in a Virtual Baseband to a Physical Baseband with Equalization - Embodiments include processes, systems, and devices for reshaping virtual baseband signals for transmission on non-contiguous and variable portions of a physical baseband, such as a white space frequency band. In the transmission path, a spectrum virtualization layer maps a plurality of transmission components associated with a transmission symbol produced by a physical layer protocol to sub-carriers of the allocated physical frequency band. The spectrum virtualization layer then outputs a physical transmission symbol composed of time-domain samples derived from the mapped frequency components and a cyclic prefix. In the receive path, a time-domain symbol received on the physical baseband is reshaped and equalized by the virtual spectrum layer in order to recompose a time-domain samples of a transmission stream in the virtual baseband. | 05-16-2013 |
20140013330 | MULTIPLE CORE REAL-TIME TASK EXECUTION - A real-time task may initially be performed by a first thread that is executing on a first core of a multi-core processor. A second thread may be initiated to take over the performance of the real-time task on a second core of the multi-core processor while the first thread is performing the real-time task. The performance of the real-time tasks is then transferred from the first thread to the second thread with the execution of the second thread on the second core to perform the real-time task. | 01-09-2014 |
20140044038 | In-Frame Acknowledgments and Retransmissions - Implementations for retransmitting erroneous portions within a transmission frame are described. A sender transmits a transmission frame and the receiver performs error detection on portions of the transmission frame in order to determine if any are received in error. The receiver sets up a feedback channel and transmits acknowledgements to the receiver to indicate that one or more portions have been received and to identify any portions that are received with errors. At least some of the acknowledgements are transmitted prior to receipt of the entire transmission frame. The sender retransmits any portions that are identified as being erroneous within the transmission frame. | 02-13-2014 |
20140051467 | Spectrum Allocation for Base Station - Embodiments include processes, systems, and devices that allow a white space base station to request available frequency ranges for white space transmission in a local area. A white space finder service models a primary user device's transmission signal propagation area using terrain data associated with the local area of the primary user device. The white space finder service also determines, based on the location of the white space base station and the modeled propagation area, one or more locally available, non-interfering frequency ranges and provides them to the white space base station. The white space base station compares the provided frequency ranges to policies and selects one or more of the available frequencies that accommodate the policies. The white space base station also maps the transmission frequency ranges to virtual frequency ranges for transmission by a software-defined radio employing spectrum virtualization. | 02-20-2014 |
20140241157 | Extended Access Point - An extended wireless access point may have many distributed radio units connected to associated processing units via a radio transmission network comprising commodity switches controlled by one or more network controllers. The one or more network controllers may use a load balancing algorithm to select a processing unit to process a signal received by a distributed radio unit. The radio units may receive a wireless signal, and generate compressed samples of the wireless signal for transport via the radio transmission network and processing by a selected processing unit. Similarly, a processing unit may generate and transmit via the radio transmission network compressed samples for decompression and transmission by a radio unit. | 08-28-2014 |
20140369321 | COOPERATIVE PHASE TRACKING IN DISTRIBUTED MULTIPLE-INPUT MULTIPLE-OUTPUT SYSTEM - A cooperative phase tracking system allows access points of a wireless network (e.g., a WiFi network) to use a clock or oscillator that may be different or independent from other access points of the same wireless network. As such, the cooperative phase tracking system eliminates a limitation of using a same clock (or oscillator) among the access points and at the same time may allow more access points to be installed for an associated wireless network to serve a larger area. Moreover, the cooperative phase tracking system may attribute intensive computations of relative phase drifts associated with the access points to a dedicated coordinator, thereby alleviating workload of the access points of the wireless network. | 12-18-2014 |