Abstract: The present invention relates to a system and method for deploying devices, such as routers (107) and mobile nodes (102) or tags, that communicate in a wireless multihopping ad-hoc communication network (100), that enables a monitoring system such as a dispatcher (212) to create a reference system to identify the location of each device. The system and method thus allows for prompt identification of the locations of persons or items, particularly firefighters and other persons operating in hazardous environments, to expedite rescue efforts.
Abstract: A system and method for providing position information of mobile user terminals (103) in a portable voice and data wireless communications network, such as an ad-hoc wireless communications network (100). More particularly, the present invention relates to a system of locating persons or assets using a centralized computing device, such as a server (125), that computes the respective locations of the terminals (103) from the respective information provided by the terminals (103) relating to their respective locations. A graphical display (121) that retrieves the location information from the centralized server (125) and generates a graphical display (121) of the location of all or selected terminals (103) based on their locations as computed by the server (125).
Abstract: The present invention provides a system and method to detect transient links in a timely and reliable way. The present invention introduces a metric that depends on the unicast data timeout measurements at the receiver node (102, 106, 107). This metric can be combined with existing solutions to estimate the link quality between nodes (102, 106, 107). Furthermore, the present invention takes the packet size into consideration when transceivers (108) update the link quality based on the packet completion rate to quantify the transient link quality more precisely.
Abstract: A system and method for providing optimum wireless communication spreading code selection such that communication channel interpath interference is minimized. In Direct-Sequence Spread-Spectrum, the autocorrelation properties of a spreading code greatly affects the inherent ability of a system to resist multipath. Low/spreading gain codes (or “short” codes) associated with high data rates do not perform well where large-amplitude multipath is present. The system and method presented herein overcomes this problem by selecting spreading codes in such a way that interference caused by multipath is minimized. The system and method does so by determining the characteristics of the radio-frequency link in order to select a spreading code that will minimize interpath interference.
Type:
Grant
Filed:
April 8, 2002
Date of Patent:
January 17, 2006
Assignee:
MeshNetworks, Inc.
Inventors:
Guénaël Thomas Strutt, Pertti O. Alapuranen
Abstract: A system and method for providing a congestion optimized address resolution protocol (ARP) for a wireless ad-hoc network. The system and method enables a node in the wireless ad-hoc network to issue an ARP request without the need to broadcast the request to all of the nodes in the wireless ad-hoc network, to thus minimize radio traffic on the wireless ad-hoc network for handling the ARP request. The node includes an address resolution protocol module which is adapted to generate an ARP request for a media access control (MAC) address corresponding to an Internet protocol (IP) address, and a transceiver which is adapted to transmit the ARP request for delivery to an access point of a network portion, such as a core LAN of the network, without broadcasting the ARP request to a plurality of other nodes in the wireless ad-hoc network. The transceiver can transmit the ARP request to the access point directly or via other nodes in the wireless ad-hoc network.
Type:
Grant
Filed:
October 23, 2001
Date of Patent:
January 3, 2006
Assignee:
MeshNetworks, Inc.
Inventors:
Charles R. Barker, Jr., Michael A. Ruckstuhl, Eric A. Whitehill
Abstract: A system and method for providing network data and system upgrades to individual nodes within an ad-hoc network without requiring network-wide information broadcasts. The system and method identifies adjacent devices authorized to share system and upgrade information. Nodes are directed to prepare and transmit requests for upgrade information from adjacent devices, such that upgrade information may be passed, from one node to the next, reaching each node in the network. The node-to-node upgrade propagation thereby replaces traditional network-wide broadcasts of upgrade information.
Abstract: An ad-hoc, peer-to-peer radio access system for cellular communications systems using time division duplex as a way of maximizing the bits/hz/km2 for cellular systems. The network architecture of the ad-hoc system allows the radio access to be integrated with the fixed components of a conventional cellular system, PSTN or ISP. The objective is to make the system of the invention transparent to the features and services provided by the external network. The advantages of such a system to a cellular operator are that significantly less infrastructure is required, and that the RF spectrum is more efficiently utilized resulting in much lower building and operating costs. The system architecture is comprised of remote terminals, routers, gateways, and at least one gateway controller that interfaces the ad-hoc system to a cellular network system. The ad-hoc system of the invention allows for both voice and data transmissions and receptions.
Abstract: A system and method for providing a congestion optimized address resolution protocol (ARP) for a wireless ad-hoc network. The system and method enables a node in the wireless ad-hoc network to issue an ARP request without the need to broadcast the request to all of the nodes in the wireless ad-hoc network, to thus minimize radio traffic on the wireless ad-hoc network for handling the ARP request. The node includes an address resolution protocol module which is adapted to generate an ARP request for a media access control (MAC) address corresponding to an Internet protocol (IP) address, and a transceiver which is adapted to transmit the ARP request for delivery to a broadcast server without broadcasting the ARP request to a plurality of other nodes in the wireless ad-hoc network.
Type:
Grant
Filed:
October 23, 2002
Date of Patent:
August 30, 2005
Assignee:
MeshNetworks, Inc.
Inventors:
Eric A. Whitehill, Michael A. Ruckstuhl, Charles R. Barker, Jr.
Abstract: A wireless local area network (LAN) for data communications. The wireless LAN includes a packet hopping access terminal (PHAST) and a packet hopping gateway (PHG). The PHAST has a first transceiver for wirelessly communicating with a client device, and a second transceiver for wirelessly receiving data packets addressed to the client device and for wirelessly transmitting data packets received from the client device in accordance with a packet hopping protocol. The PHG has a transceiver for wirelessly receiving the data packets transmitted by the PHAST and for transmitting the data packets addressed to the client device in accordance with the packet hopping protocol, and a network interface for establishing communication with a server.
Abstract: A system and method for selecting an appropriate transmit power and data rate at which a communication signal is transmitted over a link between nodes in a wireless ad-hoc communication network based on factors such as variations in path loss in the link, fading conditions, noise level estimation and overall link quality. The system and method perform the operations of computing path loss in the link based on information provided to the source node from the destination node pertaining to characteristics of a message that was transmitted by the source node and received by the destination node, determining a noise factor at the destination node, and calculating the power level and rate at which the data is transmitted over the link from the source node to the destination node based on the path loss and the noise factor. More specifically, the method calculates the power level based on the path loss, the noise factor and signal fading, and determines the rate based on the calculated power level.
Abstract: An ad-hoc, peer-to-peer radio access system having a series of remote terminals, where each remote terminal is capable of forming a link, or hop, of the routing of a call made by one of the series of terminals. The status of the battery of each terminal which may potentially form part of the routing path of a call is reported to other terminals, whereby the routing path for a call will be decided also based on the status of the battery-charge of each terminal along the routing path.
Abstract: An ad-hoc, peer-to-peer radio access system having a series of remote terminals, where each remote terminal is capable of forming a link, or hop, of the routing of a call made by one of the series of terminals. The status of the battery of each terminal which may potentially form part of the routing path of a call is reported to other terminals, whereby the routing path for a call will be decided also based on the status of the battery-charge of each terminal along the routing path.
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.
Abstract: A system and method for providing a mechanism for trans-medium address resolution on a network with at least one highly disconnected medium having multiple access points to other media. The system and method provides a “unique” media access control (MAC) address in address resolution protocol (ARP) for mobile nodes in an ad-hoc network, correctly identifying the optimum intelligent access point (IAP) for node communication where the optimum IAP changes more rapidly than traditional address updating may be able to accommodate. Medium layer routing protocols recognize medium frames addressed with this unique MAC address should be routed to the currently associated IAP, whichever IAP that might be at the moment the frame is sent.
Abstract: A system and method for reducing the number of transmissions required for a node in a communications network to range other nodes in the network, while also enabling the node to continuously monitor the reservation channel during the ranging process without the use of a second receiver, and to indicate to the ranged node and other nodes in the network that the ranging node and the ranged node are not tuning to a data channel to perform the ranging, to thus enable the node to more efficiently determine its geographic location. The system and method further enables a node in a wireless communications network to minimize the amount of time it is not monitoring the reservation channel while receiving information messages from other nodes in the network.
Abstract: A system and method for enabling a node, such as a mobile user terminal, in a wireless communications network to route data packets to other nodes in the network based on the information contained in the data packets. The system and method employs a node, adapted for use in a wireless communications network, which comprises a controller that is adapted to examine a content of a data packet addressed to a destination node, that can have an Internet protocol (IP) address to which the data packet is addressed. Based on the content of the data packet, the controller selects a routing path including at least one of a plurality of other nodes in the network via which the data packet is to be routed to the destination node. The controller can compare the content of the data packet to routing information stored in a memory, and select the routing path based on the comparison.
Abstract: A system and method for data transmission incorporating a hybrid automatic repeat request (ARQ) function at each node in an ad-hoc network. Each node is configured to calculate an optimum segment size for transmission and thereafter executes the ARQ function to transmit and receive data segments with forward error correction and error detection coding. The coding allows the node to detect and locate errors within received segments and to provide an acknowledgement only after all segments are correctly received. A negative acknowledgement from the receiving node states the location of failed segments, and only failed segments are then retransmitted. The failed segments can be retransmitted in their original location and in other segment locations which contained segments that did not fail, thus reducing maximum time to successfully deliver the segments.
Abstract: An system and method for handling broadcast network requests for auto-configuration and discovery of IP to MAC address mappings and gateway presence in wireless peer-to-peer ad-hoc routing networks. The significant portion of a node's IP address is calculated by applying a hashing function to the six-byte hardware (MAC) address. The significant portion is appended to routing advertisements, and thereby propagates passively to other network nodes. DHCP and ARP requests, as well as other broadcast type requests, are handled by the local network stack of a node, without requiring a broadcast transmission over the wireless channel.
Type:
Grant
Filed:
March 13, 2003
Date of Patent:
April 27, 2004
Assignee:
MeshNetworks, Inc.
Inventors:
William V. Hasty, Jr., Charles E. Baenen, Shawn P. Welsh
Abstract: A system and method for computing the location of a mobile terminal in a wireless communications network, such as an ad-hoc wireless communications network. In particular, the system and method estimates the location of a mobile terminal in a wireless communications network, such as an ad-hoc terrestrial wireless communications network, based on estimated distances to a plurality of terrestrial reference terminals using error minimizing techniques, such as those based on Gauss's postulate.
Abstract: A system and method for a media access control (MAC) algorithm with separate operation modes for good channel and bad channel communication. Variables, including channel vector values transmitted in request-to-send/clear-to-send (RTS/CTS) messages, are varied depending on channel mode, resulting in optimized system throughput. In a first mode, the present invention provides a system and method to estimate a channel vector length, and communicate the length to a first node and any associated groups of nodes receiving the RTS/CTS sequence. In a second mode, a maximum channel vector length is used, as retransmissions are less probable in good channels.