Abstract: Timing synchronization for mesh networks is disclosed. A temperature calibration data is received. A plurality of previously stored calibration values each corresponding to different temperatures is adjusted based at least in part on the received temperature calibration data. A temperature measurement is received. A first clock offset is determined based at least in part on the adjusted plurality of previously stored calibration values and the temperature measurement.

Abstract: In a packet communication network, a method of packet switched transport is provided using digraphs defining paths among nodes in which a graph identifier, instead of a literal destination address, is used to determine paths through the network. The nodes themselves implement a real-time mesh of connectivity. Packets flow along paths that are available to them, flowing around obstructions such as dead nodes and lost links without need for additional computation, route request messages, or dynamic routing tree construction.

Abstract: A system for congestion control for a wireless sensor network comprises a processor and a memory. The processor is configured to determine a level of congestion at one or more nodes and indicate an adjustment to network traffic in response to the level of congestion. The adjustment to the network traffic reduces the level of congestion at the one or more nodes. The memory is coupled to the processor and configured to provide instructions to the processor.

Abstract: A system for determining node locations comprises an interface for receiving a first set of measurements at a first set of nodes, the first set of nodes having known locations. The system further comprising an interface for receiving a second set of measurements at a node having an unknown location, and a processor configured for determining a location of the node with unknown location based at least in part on the first set of measurements and the second set of measurements.

Abstract: Communicating using a mesh network is disclosed. A frame length used for communicating a packet between a first node and a second node of a wireless mesh network is selected. A route from the first node to the second node is determined including one or more intermediate nodes that receive and transmit the packet. Node to node communications within the frame along the route is selected such that a communication latency time is below a predetermined limit time for a predetermined percentage of communications between the first node and the second node.

Abstract: A system for determining node locations comprises an interface for receiving a first set of measurements at a first set of nodes, the first set of nodes having known locations. The system further comprising an interface for receiving a second set of measurements at a node having an unknown location, and a processor configured for determining a location of the node with unknown location based at least in part on the first set of measurements and the second set of measurements.

Abstract: A method for synchronizing a digraph network is disclosed. The method comprises receiving timing information from a first node at a second node over a first connection specified by a first digraph link, wherein the first digraph link is a directional link specifying routing information at the first node in a network, and wherein the network includes a plurality of nodes each with a plurality of digraph links. The method further comprises calculating a synchronized time using the received timing information and a local time and sending timing information from the second node to a third node over a second connection specified by a second digraph link.

Abstract: A method for a digraph linked network to provide subnetwork communication is disclosed. The method running a first superframe in a digraph linked network containing at least one digraph link wherein a digraph link is a directional link specifying routing information between a first node and a second node in the digraph linked network. The method further comprises running a second superframe in a digraph linked network containing at least one digraph link.

Abstract: Frequency demodulation of a signal is disclosed. A first edge event and a second edge event are detected in a signal. The second edge event is an edge event subsequent in time to the first edge event. A data bit based at least in part on a timing interval between the first edge event and the second edge event is determined.

Abstract: A device for a node in a digraph network comprising is disclosed. The device comprises an internal time reference, a radio receiver, a radio transmitter. The device further comprises a temperature sensor for stabilizing the internal time reference against drifting with respect to an internal time reference of another node in the network and a microprocessor for managing the reception and transmission of information.

Abstract: A method of assigning cells in a superframe using digraph link information in a network of nodes is disclosed. The method comprises determining a total number of desired digraph links in the network of nodes wherein a digraph link is a directional link specifying routing information at each node in the network between said node and a second node, and wherein the network of nodes includes a plurality of nodes each with a plurality of digraph links. The method further comprises selecting a superframe size at least large enough to accommodate the total number of desired digraph links and assigning each desired digraph link to a cell in the superframe wherein each cell in the superframe specifies a synchronized time and frequency communication plan.

Abstract: Timing calibrator is disclosed. A first oscillator includes an output. The first oscillator includes a mechanically resonant element. A second oscillator includes an output. The second oscillator includes a quartz resonator. A frequency relater has an output, a first input, and a second input. The frequency relater has the first input coupled to the first oscillator output and the second input coupled to the second oscillator output.

Abstract: Communicating using a wireless mesh network is disclosed. A route is determined from a first node to each other node in the wireless mesh network including one or more intermediate nodes that receive and transmit the packet. A frame length used for communicating a packet is selected based on the routes from the first node to each other node in the wireless mesh network. Node to node communications are selected within the frame along the route such that a predetermined average communication latency time is achieved.

Abstract: Communicating for a mesh network is disclosed. A battery-powered node is assigned to communicate with a sending powered backbone node. The sending powered backbone node is assigned to either a first group or a second group. If the sending powered backbone node is assigned to the first group, then the sending powered backbone node sends a packet to either a gateway node or a second group receiving powered backbone node that is assigned to the second group and that is closer to the gateway node. If the sending powered backbone node is assigned to the second group, then the sending powered backbone node sends a packet to either a gateway node or a first group receiving powered backbone node that is assigned to the first group and that is closer to the gateway node.

Abstract: Configuring mesh networks based on an application is disclosed. An indication is received that a status is changed. In the event that the change in status requires a change in a mesh network configuration, a notice is transmitted to change the mesh network configuration and a local change required for the change in the mesh network configuration is initiated.

Abstract: In a packet communication network, a method and apparatus for packet switched transport is provided among intelligent nodes wherein the duty cycling of the intelligent nodes is minimized in order to maximize power life using a synchronization algorithm that assures all nodes are able to propagate information through the network without undue use of transmission and reception power. Frequency hopping time-division multiple access supports packet communication between intelligent nodes via assigned directed links, each link being assigned to a time-channel offset (cell) in a superframe, so that a link carrying a packet string between any two intelligent nodes is active only during its assigned time slot. The result is efficient use of spectrum and minimal expenditure of power.

Abstract: A method of assigning cells in a superframe using digraph link information in a network of nodes is disclosed. The method comprises determining a total number of desired digraph links in the network of nodes wherein a digraph link is a directional link specifying routing information at each node in the network between said node and a second node, and wherein the network of nodes includes a plurality of nodes each with a plurality of digraph links. The method further comprises selecting a superframe size at least large enough to accommodate the total number of desired digraph links and assigning each desired digraph link to a cell in the superframe wherein each cell in the superframe specifies a synchronized time and frequency communication plan.

Abstract: Tuning a radio oscillator frequency to a reference frequency is disclosed. A radio oscillator is set using a predetermined value loaded into an adjustment bit array. A highest selected bit is selected to be used in locating a final tuned value for the adjustment bit array. The final tuned value is determined by successively setting a selected bit starting with the highest selected bit in the adjustment bit array. And, the selected bit value in the final tuned value is determined using a measurement of the radio oscillator frequency and its relation to a reference frequency.