Patent application number | Description | Published |
20080279141 | Methods for optimal multi-channel assignments in vehicular ad-hoc networks - A communications path is established among an ordered sequence of moving nodes, representing vehicles. Available channels may differ from one node to the next node and a node cannot use the same channel for both receiving and transmitting information. Three methods are described that provide an optimal sequence of channel assignments between the nodes. A sequence of channel assignments is called optimal if it establishes a communications path from the first node in the sequence to the last node in the sequence, or, if such a path does not exist, from the first node to the farthest node possible in the sequence. The first method uses a depth-first search starting from the first node in the sequence. The second method uses a “look ahead” scheme in the depth-first search method. The third method requires only a single pass through the sequence of nodes by identifying optimal channel assignments in subsequences of nodes without a need for backtracking. | 11-13-2008 |
20090052320 | Estimator for end-to-end throughput of wireless networks - The present invention presents an architecture to dynamically measure and estimate the throughput perceived by a user during a connection in real-time in a wireless network system. The architecture system design of the present invention allows for information gathering independent of the mathematical models used and takes into account security settings in the network hosts. The present invention also sets forth a number of throughput estimators (TEs) that can be used within the architecture to gather the information needed to carry out the throughput estimation calculations. The throughput estimations can then be used for download rate control, QoS, load balancing, etc. The present invention also provides algorithms to calculate the real-time throughput experienced by a user flow. | 02-26-2009 |
20090122738 | Method of broadcasting packets in ad-hoc network - A method for distributing a packet to a plurality of moving nodes comprising receiving a packet containing at least a message, a sender identifier, a location of a sender, an identifier for a relay node and distance from the sender and the relay node, determining if a node receiving the packet is the relay node and immediately distributing the packet to a plurality of moving nodes if the receiving node is the relay node. If the receiving node is not the relay node, the method further comprises steps of waiting a set period of time, determining if a packet is received from a different sender containing the same message, within the period of time and distributing the packet to a plurality of moving nodes if a packet containing the same message is not received within the period of time. The distributed packet includes an identifier for a successive relay node. | 05-14-2009 |
20090129323 | Method for determining transmission channels for a LPG based vehicle communication network - A method for determining a transmission channel for multi-hop transmission of a data packet from a plurality of data channels in an ad-hoc network. The network includes at least one local peer group. Each local peer group has a plurality of moving vehicles as nodes. The method comprises steps of determining available channels for data packet transmission at each node, transmitting a first list of available channels to at least one other node, receiving, from the at least one other node, a second list of available channel for the at least one other node, creating an available channel table including the first and second lists of available channels, selecting a transmitting channel for a data packet based upon information in the available channel table, and advertising the selected channel to the at least one other node. | 05-21-2009 |
20090201928 | Methods for reliable multicasting in local peer group (LPG) based vehicle ad hoc networks - A method for routing a multicast message comprising the steps of receiving a multicast message including at least a message, a source identifier, a sequence number, a time-to-live value and a multicast group destination, determining if the multicast group destination is in a multicast forwarding table, determining if the message has been previously received, adding the multicast message to the multicast forwarding table if it is determined that the multicast message has not been previously received, determining if a node that received the multicast message is a forwarding node; randomly setting a wait time for forwarding the multicast message; and forwarding the multicast message at the expiration of the wait time. | 08-13-2009 |
20090238187 | Distributed Method for Minimum Delay Multi-Hop Data Delivery in Vehicular Networks - An inventive method for data delivery in a multi-hop vehicular network with multiple vehicles and intersections is presented. The method comprises, at each source vehicle, initiating packet flow, labeling packets with destination coordinates and a current location, and forwarding the packet flow, and at each intersection, selecting a header vehicle, computing a backlog indicator and listening for broadcasts with a matrix and delay information, updating the matrix in accordance with the backlog indicator if the matrix is present, otherwise initializing the matrix, forwarding the packet flow, and broadcasting the matrix from the header vehicle. In one embodiment, selection of the header vehicle is performed based on random countdown and vehicle ID. The method converges to the optimal (lowest latency) state irrespective of the initial starting point of the network and continues to tend towards the optimal state even as the network conditions alter. | 09-24-2009 |
20090285197 | METHODS FOR EFFICIENT ORGANIZATION OF VEHICLE PEER GROUPS AND EFFICIENT V2R COMMUNICATIONS - The present invention provides methods for efficient control message distribution in a VANET. Efficient flooding mechanisms are provided to fulfill the objective of flooding (delivering a message to every connected node) with a limited number of re-broadcasting by selected key nodes. A suppression-based efficient flooding mechanism utilizes a Light Suppression (LS) technique to reduce the number of flooding relays by giving up the broadcasting of a flooding message when a node observes downstream relay of the same flooding message. Additionally, a relay-node based efficient flooding mechanism selects Relay Nodes (RN) to form an efficient flooding tree for control message delivery. RNs are nodes that relay at least one control message, for instance a Membership Report (MR) to the upstream node in “k” previous control message cycles The upstream node may be the group header (GH) for the LPG. | 11-19-2009 |
20090285213 | Inter-Local Peer Group (LPG) Routing Method - An on-demand method of routing data between a plurality of local peer groups (LPG). Each LPG includes a plurality of moving nodes. The method comprises transmitting a route request message from a source node, relaying the route request message to a native boundary node; forwarding the route request message to a foreign boundary node, determining if the destination node is within an LPG for the foreign boundary node; relaying the route request message to another boundary node if the destination node is not within the LPG, relaying the route request message to the destination node if the destination node is within the LPG, receiving the routing request message at the destination node, transmitting a routing response to the source node, relaying the routing response to the source node through a path discovered by the route request, receiving the routing response at the source node, and transmitting the data, upon receipt of the routing response. | 11-19-2009 |
20090310608 | Systems and Methods for Multi-Beam Optic-Wireless Vehicle Communications - The present invention offers systems and methods for effective multiple-hop routing, multicasting and media access control for vehicle group communications that employ directional wireless radio technology. Multi-beam optic-wireless media and streamlined operations provide low-overhead communications among vehicles. Systems and methods are provided to maintain a quasi-stationary group of neighboring vehicles, enable high-throughput on-demand switching among multiple vehicles, enable group coding in the vehicle group to achieve higher throughput, and enable dynamic adjustment of link to maintain desirable vehicle group. The proposed solution builds upon the conception of a MAC-free wireless operation and quasi-stationary vehicular switched network to achieve ultra-low-overhead and high-throughput vehicle communications. | 12-17-2009 |
20100074114 | Achieving High-Rate Multi-Hop Data Delivery in Vehicular Networks - A method for high rate data delivery in a multi-hop vehicular network comprises at each source vehicle, initiating a packet having a flow tag, assigning an identifier of the content and the current location to the flow tag, and forwarding the packet; at each destination vehicle, setting a flow request and broadcasting at the current intersection; further on movement, setting the flow request at the new intersection, and at each intersection, selecting a header vehicle at the intersection, computing backlog and congestion indicators and listening for broadcasts with a matrix and the flow requests at the header vehicle, determining if the matrix is present, updating the matrix in accordance with the backlog and congestion indicators if the matrix is present, initializing the matrix and estimating the delay on the outgoing road segments if the matrix is not present, forwarding the packet flow, and broadcasting the matrix from the header vehicle. | 03-25-2010 |
20100232404 | SCALABLE DISRUPTIVE-RESISTANT COMMUNICATION METHOD - A method for transmitting data in vehicular network comprising determining a communication window between at least two nodes, grouping a plurality of fragments of content together into an aggregate fragment block, forwarding the aggregate fragment block to a target node and assembling the plurality of fragments into the content. The content is divided into the plurality of fragments. A fragment signature is generated for the fragments that contain fragment index information regarding each fragment. Each fragment is unambiguously identified by its signature. A number of fragments grouped into the aggregate fragment block is dependent on the communication window. | 09-16-2010 |
20100254350 | Fast Handoff Using GPS Technology for Mobile Telematics - The present invention relates to the reduction of handoff delays for mobile telematics applications. In particular, the present invention provides a method employing GPS technology to define IP addresses in a mobile environment in order to reduce delays and transient data loss caused by handoff from one network to another. | 10-07-2010 |
20100309823 | FULL-DUPLEX WIRELESS COMMUNICATION USING A SINGLE TRANSMITTER - A system for fall-duplex communication using a single transmitter is presented. The system comprises a base station with a signal and data processor, peripheral detectors each placed at a distance from the transmitting antenna, and a mobile device having at least a dipole antenna having a switch and a loop antenna having a switch, wherein the sending device modulates the shorting state, i.e., the electromagnetic configuration, of the wire and coil antennas using the switches, the modulating resulting in alteration in load at the base station. This alteration can be calculated based on input from the transmitting antenna and the detectors, each input having time coding. The input from the transmitting antenna can be magnitude of propagated signal and the input from each detector can comprise a quantified signal level and the quantified signal level time-delayed by propagation time. The detectors can be peripheral signal level detecting antennas. | 12-09-2010 |
20110006913 | Program and Method for Adaptive Mobile Ad-Hoc Wireless Communication - A method of controlling a wireless communication device that is installed in a moving vehicle. The method comprises receiving roadway topology information and vehicle traffic pattern information, receiving vehicle and wireless communication device performance information from a plurality of other moving vehicles, determining current position information for the moving vehicle; determining a first set of metrics for a performance of the wireless communication device installed in the moving vehicle, estimating at least one second metric related to the performance of the wireless communication device or an ad-hoc network which includes each wireless communication device and changing an operation or routing parameter for the wireless communication device based upon the estimation. The second metric is based upon at least a sub-set of the first set of metrics, the received information and the determined current position information for the moving vehicle. | 01-13-2011 |
20110010446 | Program and Method for Adaptively Maintaining a Local Peer Group in a Dynamic Environment - A method for maintaining a local peer group (LPG) for supporting communications among vehicles. The LPG is formed from a plurality of vehicles. Each vehicle is equipped with a wireless communications device. One of the vehicles is selected as a group header node (GH). The method comprises receiving periodically a heartbeat packet from the GH, the heartbeat packet including a maximum hop count, and a heartbeat cycle, forwarding the heartbeat packet until the maximum hop count is reached after waiting for a first random relay delay, which is less than a maximum allowable adjustable value, replying to the heartbeat packet with a membership report packet, forwarding a membership report packet towards the GH, and adding a vehicle that submitted the membership report packet to a LPG membership as a member node of the LPG if the membership report packet is new or updating information for a member node. | 01-13-2011 |
20110035146 | DISTRIBUTED TRAFFIC NAVIGATION USING VEHICULAR COMMUNICATION - A method for distributed traffic navigation in a vehicular network is presented. At each vehicle entering the network, information associated with the vehicular network is acquired and stored, and destination addresses are broadcasted as route requests. At each vehicle in the network, the stored information is updated through vehicle to vehicle communication. At each junction, a header vehicle is selected for listening for broadcasts to determine the presence of a matrix. If the matrix is not present, the matrix is initialized based on the stored information of the header vehicle. The header vehicle further estimates travel time on the road segments based on the matrix, calculates a backlog indicator based on the segment travel time and the route requests. The header vehicle further updates the matrix and generates a route based on the matrix. The matrix is broadcasted from the header vehicle. | 02-10-2011 |
20110134762 | Adaptation Protocols for Local Peer Group (LPG) Networks in Dynamic Roadway Environments - A method and system for determining a size of a local peer group (LPG) network in a dynamic roadway (mobile) environment is provided. In one embodiment, the method comprises measuring a roundtrip time between a first node and a second node, and utilizing the measured roundtrip time to select the size of the local peer group network from a lookup table. In another embodiment, the method comprises determining when the roundtrip time exceeds a time interval of the heartbeat signal, and when the roundtrip time exceeds the time interval of the heartbeat signal adjusting the size of the local peer group network. | 06-09-2011 |
20120201167 | Inter-Local Peer Group (LPG) Routing Method - An on-demand method of routing data between a plurality of local peer groups (LPG) of plural moving nodes comprises transmitting a route request message from a source node, relaying the route request message to a native boundary node; forwarding the route request message to a foreign boundary node, determining if the destination node is within an LPG for the foreign boundary node; relaying the route request message to another boundary node if the destination node is not within the LPG, relaying the route request message to the destination node if the destination node is within the LPG, receiving the routing request message at the destination node, transmitting a routing response to the source node, relaying the routing response to the source node through a path discovered by the route request, receiving the routing response at the source node, and transmitting the data, upon receipt of the routing response. | 08-09-2012 |