Abstract: Nodes in a network are clustered by first determining, in each node, a cluster head capability (CHC). The CHC is broadcasting, directly or indirectly, until all nodes have received the CHCs. Each node nominates, one or more candidate cluster heads based on the CHCs, and then, in each node, at least one cluster head is selected from the candidate cluster head nodes based on maximal CHCs.

Abstract: In a wireless network including a server and clients, network resources, such as time slots and channel frequencies, are managed by having the server define the resources for future use by the clients, while the clients actually allocate the resources for their exclusive use according to performance criteria determined by the clients. The network can be ad-hoc and in industrial environments with low-latency requirements.

Abstract: Conditions in a power grid are detected by sampling a voltage in the grid. A normal condition hypothesis is modeled as a sinusoid, and a transient condition hypothesis is modeled as a sum of damped sinusoids. The samples are used to construct a probability density function. A likelihood ratio based on the pdf and the hypotheses is compared to a threshold to determine whether the condition is normal or transient.

Abstract: Broken links in a sensor network are avoided by representing the network as a DODAG. A rank associated with each node defines a position of each node relative to other nodes, and the rank is in a form of a proper fraction, and the rank of each node never increases to enable loop-free routing.

Abstract: A network includes a transmitter and a receiver, wherein the transmitter includes a set of transmit antennas and the receiver includes a set of receive antennas. The transmitter duplicates a packet as copies of the packet, and selects subsets of the set of transmit antennas independent of channel characteristics between the subsets of transmit antennas and the set of receive antennas, wherein combinations of the antennas in the subsets of the transmit antennas are different. The receiver selects subsets of the set of receive antennas independent of channel characteristics between the subsets of receive antennas and the set of transmit antennas, wherein combinations of the antennas in the subsets of the receive antennas are different. The selected subsets are used to transmit the packet, and retransmit the packet in case of a failure in a previous transmission.

Abstract: An operation channel in a multi-hop network is determined. The network uses a set of channels, and one of the nodes is a network management node. The operation channel is selected in the network management node. Then, the network management node broadcasts a channel information packet including the operation channel using all channels. The channel information packet is received in each of other nodes, either directly from the network management node or from an intermediate node that received and rebroadcasted the channel information packet. Lastly, the operation channel in each node is set according to the channel information packet until the network is formed.

Abstract: A method for transmitting information in a communication network of multiple nodes, in which information transmission is partitioned into successive superframes, and in which each superframe is partitioned into a beacon period followed by a data period, which may consist of a contention free period (CFP), and each beacon period and CFP of the data period is partitioned into timeslots. The method includes allocating to at least a first node of the multiple nodes a designated timeslot in which to transmit data in at least one of a plurality of superframes, and allocating to at least a second node of the multiple nodes the same designated timeslot in which to transmit information during at least one subsequent superframe.

Abstract: A hybrid communication network for a transportation safety system includes a fixed wired nodes and mobile wireless nodes. Because the wired nodes operate independently packets transmitted by the wired nodes to the wireless nodes need to be synchronized. A downlink travel time for downlink packets traveling from a controller to the wireless nodes is determined. Then, the controller schedules downlink data intervals (DDI) based on the downlink travel time; and transmits downlink packets to the wireless nodes during the DDI, such that a latency requirement of the transportation safety system is satisfied.

Abstract: Packets are transmitted by a server to mobile nodes in a coverage area of a wireless network using a coverage and reliability map, which indicates qualities and reliabilities of links between the server and the nodes. When a new packet is received in the server, the server transmits the packet if a current load of the packets including the new packet is less than a peak load constraint. Otherwise, the new packet is delayed for one time slot. Packets are transmitted according to associated priorities.

Abstract: An operation channel in a multi-hop network is determined. The network uses a set of channels, and one of the nodes is a network management node. The operation channel is selected in the network management node. Then, the network management node broadcasts a channel information packet including the operation channel using all channels. The channel information packet is received in each of other nodes, either directly from the network management node or from an intermediate node that received and rebroadcasted the channel information packet. Lastly, the operation channel in each node is set according to the channel information packet until the network is formed.

Abstract: Broken links in a sensor network are avoided by representing the network as a DODAG. A rank associated with each node defines a position of each node relative to other nodes, and the rank is in a form of a proper fraction, and the rank of each node never increases to enable loop-free routing.

Abstract: A set of routes are discovered in a network including concentrators, smart meters and an imaginary node. Each concentrator node, a source, broadcasts a route request (RREQ) packet to the imaginary destination node. Intermediate nodes store a route as a node list (NL) in the RREQ packet and as a route table (RT) in the node. Then, each smart meter node can select a primary route and a secondary route from the smart meter node to any concentrator from the route table.

Abstract: A coverage map for a wireless network is generated. The network includes a server communicating with clients in a coverage area. The clients are mobile devices. At the server, location and reliability information from each client is received. The server then constructs and maintains the coverage map according to the location and reliability information. The coverage map is used to deliver telematic information from the server to the clients in response to requests by the clients.

Abstract: A network for managing distributed resources (DRs) is connected to an electric power system (EPS). The network includes a set of controllers, and multiple sets of the DRs, wherein each controller is connected to one of the sets of the DRs by a personal area network (PAN). A management system connects the EPS and the set of controllers by a wide area network (WAN). The EPS generates commands for selected DRs to take actions, the commands are routed to the selected DRs via the WAN and PANs.

Abstract: In a network for a safety system in a transportation system, the transportation system includes a shaft and a car arranged in the shaft. A first wall node is at a first end of the shaft and a second wall node is at a second end of the shaft to communicate safety messages with the car. Each wall node includes at least one wireless transceiver connected to one or more antennas. Each car in the shaft includes at least two wireless transceiver connected to one or more antennas, wherein the first transceiver of the car uses a first frequency and the second transceiver of the car uses a second frequency to communicate each safety messages in duplicate. A wired backbone connects the set of wall nodes to a controller of the safety system of the transportation system.

Abstract: A set of routes are discovered in a network including concentrators, smart meters and an imaginary node. Each concentrator node, a source, broadcasts a route request (RREQ) packet to the imaginary destination node. Intermediate nodes store a route as a node list (NL) in the RREQ packet and as a route table (RT) in the node. Then, each smart meter node can select a primary route and a secondary route from the smart meter node to any concentrator from the route table.

Abstract: A wireless network with a star topology has a first and second central node. The first central node starts up first and initiates the network. The second central node starts up second and synchronizes to the first central node, and wherein one node is in active mode and the other node is in standby mode, and a set of leaf nodes configured to communicate only with the active node.

Abstract: A network includes a transmitter and a receiver, wherein the transmitter includes a set of transmit antennas and the receiver includes a set of receive antennas. The transmitter duplicates a packet as copies of the packet, and selects subsets of the set of transmit antennas independent of channel characteristics between the subsets of transmit antennas and the set of receive antennas, wherein combinations of the antennas in the subsets of the transmit antennas are different. The receiver selects subsets of the set of receive antennas independent of channel characteristics between the subsets of receive antennas and the set of transmit antennas, wherein combinations of the antennas in the subsets of the receive antennas are different. The selected subsets are used to transmit the packet, and retransmit the packet in case of a failure in a previous transmission.

Abstract: A hybrid communication network for a transportation safety system includes a fixed wired nodes and mobile wireless nodes. Because the wired nodes operate independently packets transmitted by the wired nodes to the wireless nodes need to be synchronized. A downlink travel time for downlink packets traveling from a controller to the wireless nodes is determined. Then, the controller schedules downlink data intervals (DDI) based on the downlink travel time; and transmits downlink packets to the wireless nodes during the DDI, such that a latency requirement of the transportation safety system is satisfied.

Abstract: A hybrid communication network for a transportation safety system includes a wired network including a set of fixed nodes. Each fixed node includes a wired interface for connecting the fixed node to the wired network and at least one wireless interface. The set of fixed nodes further includes a head node at a first end of the wired network connected to a controller, a terminal node at a second end of the wired network, and a set of relay nodes arranged between the head node and the terminal node. A wireless network includes a set of mobile nodes and a set of fixed nodes connected to the wired network. Each mobile node includes at least one of the wireless interfaces, and each mobile node is arranged in a moveable car.