Abstract: An “identical beacons” field (401) is inserted near the beginning of a transmitted beacon (403) that contains either an integer equal to the number of consecutive identical beacons sent (i.e., identical to the one presently being transmitted) or a repetition bit indicating whether or not the beacon contains changed information when compared to a prior-sent beacon. After sleeping awhile, a node (302-304) wakes up, receives a first portion of the beacon containing the identical beacons field, and analyzes the identical beacons field. Based on the analysis, the node makes a decision on whether to remain “awake” for reception of the remaining beacon or to return to sleep.

Abstract: A network protocol for low-cost, low-power devices coupled to a self-organizing wireless network using a spanning tree backbone architecture is described. In this protocol, physical and logical network construction and maintenance operations, which supports efficient data routing in the network, are performed. The construction phase in conjunction with the maintenance phase insures the self-organizing capability of the network. At the same time, the maintenance operations provide a self-healing mechanism so that the network can recover from node failures and a self-updating mechanism so that the network can expand as more nodes enter the system. Also, the logical backbone hierarchy will facilitate multi-hop communication. The construction of a logical layered spanning tree backbone architecture from an underlying physical topology allows seamless data communication routing between all nodes in the network.

Abstract: An “identical beacons” field (401) is inserted near the beginning of a transmitted beacon (403) that contains either an integer equal to the number of consecutive identical beacons sent (i.e., identical to the one presently being transmitted) or a repetition bit indicating whether or not the beacon contains changed information when compared to a prior-sent beacon. After sleeping awhile, a node (302-304) wakes up, receives a first portion of the beacon containing the identical beacons field, and analyzes the identical beacons field. Based on the analysis, the node makes a decision on whether to remain “awake” for reception of the remaining beacon or to return to sleep.

Abstract: An “identical beacons” field (401) is inserted near the beginning of a transmitted beacon (403) that contains either an integer equal to the number of consecutive identical beacons sent (i.e., identical to the one presently being transmitted) or a repetition bit indicating whether or not the beacon contains changed information when compared to a prior-sent beacon. After sleeping awhile, a node (302-304) wakes up, receives a first portion of the beacon containing the identical beacons field, and analyzes the identical beacons field. Based on the analysis, the node makes a decision on whether to remain “awake” for reception of the remaining beacon or to return to sleep.

Abstract: A network protocol for low-cost, low-power devices coupled to a self-organizing wireless network using a spanning tree backbone architecture is described. In this protocol, physical and logical network construction and maintenance operations, which supports efficient data routing in the network, are performed. The construction phase in conjunction with the maintenance phase insures the self-organizing capability of the network. At the same time, the maintenance operations provide a self-healing mechanism so that the network can recover from node failures and a self-updating mechanism so that the network can expand as more nodes enter the system. Also, the logical backbone hierarchy will facilitate multi-hop communication. The construction of a logical layered spanning tree backbone architecture from an underlying physical topology allows seamless data communication routing between all nodes in the network.

Abstract: A communication access protocol improves the accessibility of devices operating on an asynchronous network (100), while supporting reduced power consumption. The network (100) includes a mediation device (130) for facilitating communications among network devices. Generally, each network device periodically transmits beacon signals to advertise its presence, and listens for communication signals targeted at the network device (532, 534). A device initiating communication with another operates in one of at least two operating modes in order to establish communications (536, 537, 538). In one mode, the initiating device communicates with the mediation device in order to derive timing information for the other device (537). In another mode, the initiating device listens to receive beacon signals directly from the target device in order to synchronize communications with the device (538).

Abstract: A system for locating a number of devices (112-130) by measuring signals transmitted between known location devices (112-118, 134-138, 214-218, 224-228) and unknown location devices (120-130, 222), and signals transmitted between pairs of unknown location devices (120-130,222), entering signal measurements into a graph function that includes a number of first sub-expressions, a number of which include signal measurement prediction sub-expressions, and have extrema when a predicted signal measurement is equal to an actual signal measurement, and optimizing the graph function.

Abstract: A system for locating a number of devices (112-130) by measuring signals transmitted between known location devices (112-118, 134-138, 214-218, 224-228) and unknown location devices (120-130, 222), and signals transmitted between pairs of unknown location devices (120-130, 222), entering signal measurements into a graph function that includes a number of first sub-expressions, a number of which include signal measurement prediction sub-expressions, and have extrema when a predicted signal measurement is equal to an actual signal measurement, and optimizing the graph function.