Abstract: Techniques are provided for reliably distributing network management information in and ad hoc multi-hop wireless network which includes a number of existing nodes. A first node selects a particular timeslot in a dedicated channel based on the network management information received from the neighbor nodes and determines, via a contention channel, if the particular timeslot is being used by any neighbor nodes of the first node. If the particular timeslot is determined to be unused, then it is assigned to the first node for periodically transmitting network management information.

Abstract: A terminal for operation within an ad-hoc, peer-to-peer radio system wherein the system includes a series of radio terminals forming a service group. The terminal having a transceiver for communicating with terminals in the same service group, computer means, and memory for storing program software. Within the system, the terminal establishes a connection with one radio terminal based on time-division access; initiating an outgoing call from the radio terminal including registering with another radio terminal for serving as a node in the call connection by transmitting a registration request; and initially transmitting said registration request on a last time slot(TS) of a respective time frame (TF), said last time slot serving as a configuration channel.

Abstract: Techniques are provided for reliably distributing network management information in and ad hoc multi-hop wireless network which includes a number of existing nodes. A first node selects a particular timeslot in a dedicated channel based on the network management information received from the neighbor nodes and determines, via a contention channel, if the particular timeslot is being used by any neighbor nodes of the first node. If the particular timeslot is determined to be unused, then it is assigned to the first node for periodically transmitting network management information.

Abstract: A wireless communication device (e.g., 102) employs a method and apparatus for determining distances between wireless communications devices in a wireless communication network (100). The wireless device receives an incoming message signal (117) from at least one other wireless device (e.g., 101, 103-104) in the network. The message signal(s) includes a time of arrival of a ranging signal (121) previously transmitted by the wireless device. Responsive to receiving the message signal(s), the wireless device receives one or more incoming ranging signal(s) (120) from the other wireless device(s). Each ranging signal is received in a frequency range that is substantially less than the frequency range in which the messaging signal(s) was received.

Abstract: A method and system for determining the time of arrival of a direct radio signal. The system including a receiver (210) for receiving a plurality of signals, wherein each of the plurality of received signals has an associated time of arrival. The system further including a processor (215) adapted to compute a impulse response function of a received signal; decompose an impulse response function comprising the time of arrival for each of the plurality of received signals; and identify a smallest time of arrival from the decomposed impulse response function.

Abstract: The present invention provides a method for computing the position of a mobile device (200,405) operating in a wireless network (100). The system includes a receiver, adapted to receive respective signals from each of at least four reference devices (410,415,420,425) at the mobile device (405), each respective signal including information representing a Time of Flight between the mobile device (405) and the associated fixed reference device. The system includes a processor (215), to estimate the location of the mobile device (200,405) by computing at least three Apollonius circles (500,600,700) between the mobile device (405) and each of the at least three different pairs of fixed reference devices, wherein the computed Apollonius circles are indicative of the distance between the mobile device (405) and each of the associated fixed reference devices of each pair; and calculating the location of the mobile device (405) as the intersection of the computed Apollonius circles.

Abstract: A system and method for providing geographic location information to of at least one fixed reference device in a wireless network, the method comprising: determining a geographic location of the at least one fixed reference device within an image, such as a Geographic Information System (GIS) image, where the GIS image comprises a plurality of pixels each having an absolute geographic location value associated with it, and where the geographic location of the at least one fixed reference device is defined with respect to the absolute position values associated with at least one pixel that is proximal to an image of the at least one fixed reference device within the GIS image; and providing the determined geographic location information to the at least one fixed reference device.

Abstract: A system and method for synchronizing a wireless network comprising a first node operable pursuant to a first time-division multiple access (TDMA) scheme and a second node operable pursuant to a second TDMA scheme, wherein the first TDMA scheme and the second TDMA scheme each comprise a plurality of ticks, and wherein the first node and the second node each comprise a tick counter for determining the time moment at which a transmission is made or at which a signal is received by the node.

Abstract: A method for routing data packets from a source to a destination in a wireless communication network comprising a plurality of nodes, wherein each node is in uplink-downlink association with at least one neighboring node, and wherein each node comprises a registration table identifying all downlink nodes that are associated with the node, the method comprising: sending an Open Stream message from a source node which specifies a destination node; and receiving the Open Stream message at the uplink node of the source node, wherein the uplink node relays the Open Stream message to the destination node if the destination node is registered in the registration table of the uplink node.

Abstract: An adaptive train model (ATM) for predicting train consist reactions to specific stimuli using a system including at least one measurement sensor located on the train consist, a data base, and a computer. The ATM collects sensor data as the consist is moving, determines a consist force balance utilizing the sensor data and the computer, determines a set of consist coefficients using the computer, and predicts train consist kinetic characteristic values using the consist force balance and the set of consist coefficients.

Abstract: A system and method for applying an algorithm to distance measurements between nodes in an ad-hoc communications network (100). The algorithm is located at an individual node (102, 106, 107) of the ad-hoc network (100) and processes collected data via a multi-path filter to ensure that range measurement data is correct, and if so, include such measurement data in a historical data matrix in which old measurement data is eliminated. During periods where received signals are unable to provide correct distance measurements due to reflections affecting the path between nodes or media absorption or radio energy, distance estimates may be obtained from this accurate historical data.

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: The present invention provides a bandwidth efficient system and method of measuring the range between nodes (102, 106, 107) in a wireless communications network (100) with one-way data transfer, where each node (102, 106, 107) periodically transmits a message that contains information regarding neighboring nodes (102, 106, 107) from which any prior messages have been received by the transmitting node (102, 106, 107). A node (102, 106, 107) receives the messages transmitted from neighboring nodes (102, 106, 107) in the network (100), and records the times of arrival of the received messages. The node (102, 106, 107) receiving those messages can thus determine the respective distances between itself and the neighboring nodes (102, 106, 107) based on the respective time of arrivals of the received messages and the respective information included in the respective messages.

Abstract: A system and method for improving the accuracy in computing the location of a mobile subscriber device connected in a wireless network. The system and method employ a predictive filter, including a measurement weight algorithm to decrease standard deviation error, to correctly determine a location of a mobile subscriber device. The predictive filter requires lower levels of computation, which allows for real-time processing on low-speed central processing units commonly used in wireless networks.