Abstract: A sensor network has a plurality of wireless sensors which transmit to an intermediate receiving device which relays data to a central server. A method is provided for receiving data packets at the intermediate receiving device from a plurality of the transmitting devices. Data packets are sensed on a communication medium at the receiving device and the total traffic intensity of data packets from the transmitting devices is estimated. A detection threshold for data packets is provided and adapted as a function of the total intensity. The receiving device receives data packets with a signal strength above the current detection threshold.

Abstract: Methods and algorithms for path estimation in a wireless mesh network are described. In an embodiment, each node calculates its cost for a packet flow based on the back-log at the node and the cost of downstream neighbor nodes for the flow. The cost is communicated to the upstream neighbor nodes for the flow. When a node has an opportunity to transmit a packet, a flow is selected by the node based on the back-log at the node and the costs received from each of the downstream neighbor nodes. These costs are then also used to select a downstream neighbor node is selected based on the costs received from each of the downstream neighbor nodes. A packet re-ordering algorithm is also described which intercepts packets received at a node and delays delivery of the packet to the IP layer if an earlier packet in the sequence of packets has not been received.

Abstract: Each node or link of an ad hoc network assists in the distributed allocation of a data channel to increase fairness, even in a multi-hop network, by tracking a measure of link weight for itself and sharing this information over a control channel with neighboring nodes. The metric can be provided over a dedicated control channel, added as a header to data communication on a data channel, or inferred by monitoring data traffic from the neighboring node. The link weight can be adjusted by a link quality factor based on provided or inferred metrics such as transmission rates, ratio of transmission errors, idle time, etc. For multiple flow queues at a subject node, one with a higher transmission rate can be selected for increased fairness. When a packet is received, medium access includes allocating bandwidth, including bonding multiple frequencies that are determined to be available to both nodes.

Abstract: A communication device cognitively monitors interference signals across a communication band so that adaptations for physical and medium access control (MAC) of data packet transmissions are appropriate for a particular interference signal. Characteristics of an interference signal of interest (e.g., bandwidth, power and/or duration relative to an average data packet transmitted over a communication channel of the communication device) are sensed for an appropriate adaptation (e.g., forward error correction, modulation technique, back off, request to send/clear to send protocol, etc.). Patterns for known types of interference sources can be compared so that when recognized an associated adaptation can be used.

Abstract: A method of transmitting data across a wireless mesh network is described which uses network coding at each of the intermediate nodes between the source node and the destination node. Each intermediate node also controls the rate at which it broadcasts packets based on link congestion and the backlog of packets at each of the possible next-hop nodes for the data flow.

Abstract: A sensor network has a plurality of wireless sensors which transmit to an intermediate receiving device which relays data to a central server. A method is provided for receiving data packets at the intermediate receiving device from a plurality of the transmitting devices. Data packets are sensed on a communication medium at the receiving device and the total traffic intensity of data packets from the transmitting devices is estimated. A detection threshold for data packets is provided and adapted as a function of the total intensity. The receiving device receives data packets with a signal strength above the current detection threshold.

Abstract: A sensor network has a plurality of wireless sensors which transmit to an intermediate receiving device which relays data to a central server. A method is provided for receiving data packets at the intermediate receiving device from a plurality of the transmitting devices. Data packets are sensed on a communication medium at the receiving device and the total traffic intensity of data packets from the transmitting devices is estimated. A detection threshold for data packets is provided and adapted as a function of the total intensity. The receiving device receives data packets with a signal strength above the current detection threshold.