Abstract: Time synchronization for nodes of a broadcast-only network is provided by combining two methods. The first method provides relative synchronization of communication frames of node broadcasts, so that all nodes have frames with aligned start and end times. The second method associates a network time with each frame at each node (i.e., each node locally tracks this network time). When a time-stamped message is received by a node, the node network time is set to the larger of its current value or the time stamp of the received message. Each node increments its network time by the same amount from one communication frame to the next.

Abstract: Monitoring the status and behavior in a wireless network is provided. In a wireless network of operational nodes, one or more monitoring nodes are embedded in the network to monitor the status and behavior of the network without unintentionally disturbing the network. The monitoring nodes receive state information from the operational nodes. The operational nodes can be nodes in a wireless sensor network or a broadcast-only distributed wireless network. State information is sent in small state messages during the idle period of the communication frame of the operational node to be received by monitoring nodes. Transmission of state messages in the idle period for monitoring purposes does not disturb communication between operational nodes and can be energy efficient. The monitoring nodes can also intercept communications between operational nodes. Providing feedback to and influencing operational nodes are also provided.

Abstract: Communication in a broadcast-only distributed wireless network of nodes is provided. Each of the nodes of the network uses a repeated communication frame with an idle period and a TDMA schedule for active communication. The active TDMA schedule of at least some of the nodes in the network are aligned and synchronized. The distributed network does not require a central node for coordinating the TDMA schedules of another node or for synchronizing the communication frames. TDMA slots of the TDMA schedule are used for broadcasting and receiving messages. A node broadcasts a message without the use of an address of the receiving node. Communication frames having dynamic properties, such as communication frame length and start time, TDMA schedule position and length, and idle period position and length, are provided. Distributed functions for nodes to search for and synchronize with other nodes are also provided.

Abstract: Distinct physical channels in a network are exploited to provide capabilities that go significantly beyond conventional hybrid networks. In a first aspect, distinct physical channels are employed to determine physical relationships of the nodes with respect to each other. For example, whether or not the nodes of an RF wireless system are in the same room of a building can be determined by using optical messages passed between the nodes. In a second aspect, a first physical channel is employed for synchronized broadcasting, and a second physical channel is employed to enhance the capabilities of the synchronized broadcast network. For example, the nodes of an RF wireless broadcast network can be selectively commissioned (i.e., sensitized) with optical signals to commands that are broadcast on the RF network.

Abstract: Time synchronization for nodes of a broadcast-only network is provided by combining two methods. The first method provides relative synchronization of communication frames of node broadcasts, so that all nodes have frames with aligned start and end times. The second method associates a network time with each frame at each node (i.e., each node locally tracks this network time). When a time-stamped message is received by a node, the node network time is set to the larger of its current value or the time stamp of the received message. Each node increments its network time by the same amount from one communication frame to the next.

Abstract: Monitoring the status and behavior in a wireless network is provided. In a wireless network of operational nodes, one or more monitoring nodes are embedded in the network to monitor the status and behavior of the network without unintentionally disturbing the network. The monitoring nodes receive state information from the operational nodes. The operational nodes can be nodes in a wireless sensor network or a broadcast-only distributed wireless network. State information is sent in small state messages during the idle period of the communication frame of the operational node to be received by monitoring nodes. Transmission of state messages in the idle period for monitoring purposes does not disturb communication between operational nodes and can be energy efficient. The monitoring nodes can also intercept communications between operational nodes. Providing feedback to and influencing operational nodes are also provided.

Abstract: Communication in a broadcast-only distributed wireless network of nodes is provided. Each of the nodes of the network uses a repeated communication frame with an idle period and a TDMA schedule for active communication. The active TDMA schedule of at least some of the nodes in the network are aligned and synchronized. The distributed network does not require a central node for coordinating the TDMA schedules of another node or for synchronizing the communication frames. TDMA slots of the TDMA schedule are used for broadcasting and receiving messages. A node broadcasts a message without the use of an address of the receiving node. Communication frames having dynamic properties, such as communication frame length and start time, TDMA schedule position and length, and idle period position and length, are provided. Distributed functions for nodes to search for and synchronize with other nodes are also provided.