177 results about "Bandwidth efficient" patented technology

A method is presented that includes generating a content identifier for at least one article. The content identifier identifies the article. Also, determining if at least a portion of the at least one article is present on at least one device based on the content identifier. The at least one portion of the at least one article is stored if the at least one portion of the at least one article is determined to be not present on the at least one device. Also presented is a method including requesting at least one article by a content identifier representing the article. The at least one article is determined if it is present on at least one device based on the content identifier. At least one portion of the at least one article is returned if the at least one portion of the at least one article is determined to be present on the at least one device.

An Automatic Repeat reQuest (ARQ) error correction method optimized for protecting real-time audio-video streams for transmission over packet-switched networks. Embodiments of this invention provide bandwidth-efficient and low-latency ARQ for both variable and constant bit-rate audio and video streams. Embodiments of this invention use timing constraints to limit ARQ latency and thereby facilitate the use of ARQ packet recovery for the transport of both constant bit rate and variable bit rate media streams.

A radio link management system for a home or office substantially (i) an ad hoc network of agents wirelessly communicating among themselves, while (iii) clients wirelessly communicate with proximate agents. Control of the network may be centralized as network controller integrated with an agent, or may be distributed upon the network of agents. Some agent or agents, which may include an agent that is also the network controller, typically serves as a gateway device which connects to a worldwide communications network external to the home or office, normally by fiber or by wire.Each agent is most commonly a small radio transceiver plus logic and power supply that mounts upon a wall and plugs directly into an AC power socket. Agents wirelessly communicate among themselves and with the controller-which may be centralized or distributed-in a bandwidth-efficient mode since prime power is not an issue. Each client, which is most commonly a battery-powered user device, wirelessly radio communicates with one or more proximately-located agents. Consistent with overall demand for the radio resource, parameters for radio communication are allocated ad hoc in a manner which is (a) client-dependent, and which (b) uses the least power from the battery-powered client. The agents establish an ad-hoc network among themselves, with routing among and between the agents being both multi-hop and "minimum hop" to conserve bandwidth. Accordingly both power and bandwidth are conserved, each as and where required and desired.

A discrete multitone stacked-carrier spread spectrum communication method is based on frequency domain spreading including multiplication of a baseband signal by a set of superimposed, or stacked, complex sinusoid carrier waves. In a preferred embodiment, the spreading involves energizing the bins of a large Fast Fourier transform (FFT). This provides a considerable savings in computational complexity for moderate output FFT sizes. Point-to-multipoint and multipoint-to-multipoint (nodeless) network topologies are possible. A code-nulling method is included for interference cancellation and enhanced signal separation by exploiting the spectral diversity of the various sources. The basic method may be extended to include multielement antenna array nulling methods for interference cancellation and enhanced signal separation using spatial separation. Such methods permit directive and retrodirective transmission systems that adapt or can be adapted to the radio environment. Such systems are compatible with bandwidth-on-demand and higher-order modulation formats and use advanced adaptation algorithms. In a specific embodiment the spectral and spatial components of the adaptive weights are calculated in a unified operation based on the mathematical analogy between the spectral and spatial descriptions of the airlink.

A bandwidth efficient advanced modulation waveform modem using concatenated iterative turbo coding and continuous phase modulation is disclosed. A demodulator in the modem has a turbo decoder and a decision feedback carrier and time tracking algorithm to track a carrier and adjust timing. The decision feedback carrier and time tracking algorithm may use an APP decoder as a decision device to provide symbol decisions at a high error rate and low latency for a coded input data stream. A symbol phase estimator produces a symbol phase error estimate from the symbol decisions. An erasure decision function decides which symbol decisions are correct and which symbol decisions are erasures. A carrier tracking function receives the symbol phase error estimates when the symbol decisions are correct and receives erasure inputs when the symbol decisions are erasures to maintain carrier tracking.

A process is introduced that determines contour requirements from many factors. Based on the contour requirements, the process either generates at least one content-derived signature contour from either many content identifiers or at least one content-derived signature contour, or generates at least one optimized content-derived signature contour from contour-related data and either at least one content-derived signature contour or a derivation from at least one content-derived signature contour.

A modem that provides efficient use of wireless network bandwidth in the presence of multi-user interference and noise comprising a multi-user detection module (115), a data formatting module (120), a control processor (125) and a demultiplexer (135).

A highly bandwidth-efficient communications method is disclosed that enables remote stations to synchronize in time and frequency to their serving base station. The invention enables a base station and its remote stations in a cell to synchronize in a noisy environment where signals interfere from other base stations and remote stations in other cells. The base station forms a forward synchronization burst that includes a plurality of tone frequencies arranged in a distinctive orthogonal frequency division multiplexed pattern unique to the base station. The unique pattern enables a remote station to distinguish the base station's bursts from other signals present in a crowded area. The distinctive orthogonal frequency division multiplexed pattern can be a Hadamard code pattern, for example. When the a base station has received a signal on a reverse link from a remote station, having significant interference, the base station selectively forms a request signal requesting the remote station to respond with a reverse synchronization burst that includes a plurality of tone frequencies arranged in the same distinctive orthogonal frequency division multiplexed pattern. The base station then transmits the forward synchronization burst and the request signal at a base station reference instant of time to the remote station. The reverse synchronization signals selectively occupy time slots in the transmission frame from the remote station to the base station, that would otherwise be occupied by channel control or traffic signals. Only when the base station requests the remote station to respond with a reverse synchronization burst, does this burst preempt the time slot from its other uses.

This invention modulates data onto a radio channel in such a way that the deleterious effects of the channel are reduced. This is accomplished in three steps: first, the information signal is modulated using a phase-differential modulation scheme. Second, the modulated signal is spread in both time and frequency by passing it through a dispersive filter, transmitting it through the channel, and removing the spreading using a dispersive filter in the receiver with the opposite characteristics of the filter in the transmitter. The third step, after demodulation, is to pass the signal through a low-pass filter to gather up the signal energy which has been dispersed by the channel. All three of these steps can be implemented with simple functional blocks, making this system very inexpensive to implement. Also included are two methods for enhancing the data throughput of the basic system, making it more bandwidth efficient.

The high quality PCS communications are enabled in environments where adjacent PCS service bands operate with out-of-band harmonics that would otherwise interfere with the system's operation. The highly bandwidth-efficient communications method combines a form of time division duplex (TDD), frequency division duplex (FDD), time division multiple access (TDMA), orthogonal frequency division multiplexing (OFDM), spatial diversity, and polarization diversity in various unique combinations. The method provides excellent fade resistance. The method enables changing a user's available bandwidth on demand by assigning additional TDMA slots during the user's session.

A communication system includes a transmitter that transmits both wideband data and narrowband data on a link and a receiver that receives the wideband data and the narrowband data on the link. The receiver demultiplexes the wideband data and the narrowband data into separate data streams so that the link effects transmission of a narrowband channel and a wideband channel. The system achieves high link availability on a link using bandwidth efficient modulation by using a more robust modulation format for the narrowband channel to enable higher link availability for the narrowband channel (carrying the narrowband data on the link) than for the wideband channel. The link may employ bandwidth efficient modulation or may be compatible with prior art wideband modulation formats.

Efficient usage of available spectrum is increased by logically dividing government licensed frequency channels into sub-channels, each of which can individually transmit a signal between a base unit and terminal. The sub-channels are each offset from the center of the frequency channel by a unique offset amount to avoid interference. Power control, sub-channel interference cancellation, and frequency control are employed to minimize the effects of out-of-band sub-channel signals on adjacent sub-channels. Any given sub-channel can be dynamically configured to transmit voice or data signals. Further spectral efficiency is realized using time division multiplexing on some or all of the sub-channels.

A central node sends a query indicating at least one key performance indicator (KPI) and a first KPI filter criterion to one or more edge nodes causing each edge node to cache subscriber data from each subscriber having a KPI value corresponding to the KPI. The central node receives subscriber data, responsive to the query, and aggregates the subscriber data according to each subscriber and the corresponding KPI value to yield an aggregated initial subscriber dataset and sends a subsequent query to each edge node that (for each edge node) indicates a subscriber from the initial subscriber dataset not returned by the edge node. The central node receives subsequent subscriber, responsive to the subsequent query, and aggregates the subsequent subscriber data with the initial subscriber dataset to yield a final subscriber dataset that indicates a total KPI value for each subscriber.

A method, computer program product, system and apparatus are presented for reducing wasted bandwidth due to supercasting multicast cells through a router switch fabric. In one embodiment of the present invention, signatures of a switch fabric destination address are generated and compared. A signature is an information-rich representation of the fabric destination address that is generated using the fabric destination address. Therefore, supercasting can be minimized by combining fabric destination addresses with like signatures. Aspects of the present invention include generating the signatures using random permutation maps of the set of switch fabric ports or determining intersections of a fabric destination address with a selection of subsets of the switch fabric ports. Signature-based solutions for supercast minimization can be performed in a time-efficient manner and be implemented online, while solutions that can generate a more optimal solution but may take a longer time to perform, such as row-clustering, can be implemented off-line. A further aspect of the invention, incorporates an off-line row-clustering supercast minimization method with an on-line signature-based supercast minimization method.

Video content is delivered in a bandwidth efficient manner to a destination device. The video content is analyzed and a compression operation is performed on the video content prior to delivery to the destination device. Any audio associated with the video content is maintained in synchronization with the video content. The compression of the video can be performed in a variety of manners including single transmission of static frames, combining substantially similar frames so that only a single frame representing the combination is transmitted, and only transmitting dynamically changing or active portions of the video content.

A technique is described for performing multiple video processing tasks in a single operation, as opposed to serially. For instance, a technique is described for de-interlacing a principal video stream at the same time that at least one video sub-stream is combined with the principal video stream. Performing these tasks in a single call to a graphics processing unit, as opposed to staggered serial calls, reduces the bandwidth requirements of the processing operations. This, in turn, can enable a computing device to perform these multiple operations at full frame rate. In one implementation, different texturing units are respectively assigned to the principal video stream and the video sub-stream. The graphics processing unit interacts with these texturing units and associated memory locations substantially in parallel, thus providing the above-described bandwidth savings.

A bandwidth efficient routing protocol for wireless ad-hoc networks. This protocol can be used in ad-hoc networks because it considerably reduces control overhead, thus increasing available bandwidth and conserving power at mobile stations. It also gives very good results in terms of the throughput seen by the user. The protocol is a table-driven distance-vector routing protocol that uses the same constraints used in on-demand routing protocols, i.e., paths are used as long as they are valid and updates are only sent when a path becomes invalid. The paths used by neighbors are maintained and this allows the design of a distance-vector protocol with non-optimum routing and event-driven updates, resulting in reduced control overhead.

In one embodiment, the present invention is a method and an apparatus for bandwidth efficient distribution of content over a computer network. In one embodiment, a server cooperates with clients to reduce the usage of server bandwidth, thereby reducing bandwidth-associated distribution costs. The server controls the way that content is distributed within the system, and the clients/receivers may act as intermediate forwarders of data packets. In one embodiment, this is accomplished by sending data items to a first group of receivers on a packet-by-packet basis using unicast communication. The first group of receivers then sends the packets on to a second set of receivers, and the process continues until the packet is forwarded to all intended receivers.

The present invention provides an enhanced H-ARQ scheme that optimizes bandwidth utilization and spectrum efficiency. When an H-ARQ attempt is unsuccessful due to loss or error over a hop between the BS and MS/SS, then only the first node in the hop chain that fails to decode the packet transmits another H-ARQ attempt. The BS determines the first node that fails on decoding based on certain information such as the feedback information sent from the nodes on the path. The previous node of the failed node is then instructed to retransmit by the BS.

A technique and system that generates transcoded media files from requested original compressed media files, and then transmits the transcoded media files to a requester rather than the original compressed media files. Advantageously, the disclosed solutions provide a more bandwidth efficient downloading of media files to a requesting device. In addition, the disclosed solutions also fully support the seek function that is typically employed in media player devices. By correlating the requested original compressed media files time-wise with the generated transcoded media files, seek requests generated by a requesting device can be mapped to the appropriate or a close proximity to the transcoded media file.