Abstract: Techniques are provided for selecting a root node in an ad hoc network that contains a plurality of nodes including a first node. According to one implementation of these techniques, a first node can receive a message from at least one of the other nodes. Each message includes a number of primary factors associated with a particular node regarding capabilities of the particular node. The primary factors associated with each node can then be evaluated, and an attempt can be made to select the root node based on the primary factors associated with each node. If the first node is unable to select the root node based on the primary factors associated with each node, then the root node can be selected based on secondary factors associated with each node.

Abstract: A system and method for locating and using multiple routes to transmit sub-packets of data from a source node to a destination node in an ad-hoc network, thus preventing intermediate nodes in any one transmission path from intercepting a useful amount of information. The system and method routes communications between a source node and a destination node via multiple routes, selected in a random fashion. Further protection is achieved by breaking data packets into sub-packets requiring reassembly at the destination node.

Abstract: A system and method to control congestion in a multihopping wireless communication network (100). The system and method distribute the congestion information back to the ingress points (106) and traffic source nodes (102, 106, 107) in the network (100) through the actual route of the data flow that contributes to the congestion. The system and method therefore avoid bottleneck points (102-5) in the network (100) to reduce congestion. The system and method can be used for packet-based, route-based or flow-based traffic shaping in a multihop wireless network (100) employing different media access control (MAC) and routing layer protocols. Moreover, the system and method is capable of distributing congestion and service differentiation information between different interfaces in the network (100).

Abstract: A system and method for evaluating at least one communication link between a transmitting node and a receiving node in a communications network. The system and method perform the operation of assigning respective link quality values to the respective communication links based on a transmit power level (TPL) value at which the respective data packets were transmitted by the transmitting node over the respective links, a received sensitivity (RS) value of the receiving node receiving the data packets, and a receive signal strength indication (RSSI) value provided by the network for each respective link. Based on the link quality values, the system and method can determine whether additional data packets are to be sent by the transmitting node to the receiving node via the communication link. Specifically, the link having the highest link quality value is selected.

Abstract: A system and method that creates an abstraction of the physical layer of a wireless communication network (100), in particular, a wireless ad-hoc peer-to-peer communication network (100), and that normalizes the feedback from the physical layer to enable multiple types of nodes (102, 106, 107) in the wireless network to operate using a common wireless routing protocol. This routing protocol uses a link quality metric to determine the best route regardless of how it actually chooses the route or disseminates such link quality information. The generalized routing metric can be derived for any node (102, 106, 107), regardless of its relative performance or its media access control (MAC) technology. The system and method also create a transaction summary that can be used for link adaptation and link quality estimation to determine, for example, future data rates, link quality/routing metrics, and transmit powers.

Abstract: A system and method for controlling the quantity of training symbols in a transmission sequence sent by a terminal (102, 106, 107) in a wireless network (100). The transmission sequence include training symbols and data symbols. The system and method determine the number of data symbol errors which are close to training symbols in the transmission sequence, determine the number of symbol data errors which are far from training symbols in the transmission sequence, and adjust the quantity of training symbols in the transmission sequence based on a result of a comparison of the ratio of the number of data symbol errors which are close to training symbols to the number of data symbol errors which are far from training symbols.

Abstract: A communication network includes a base station, a relay station, and a subscriber station. The base station is communicatively coupled to a backhaul for routing one or more messages through the backhaul to a destination. The relay station is communicatively coupled to the base station and further communicatively coupled to an alternate backhaul. The relay station includes a relay station mode of operation for relaying messages between the base station and the subscriber station, and a base station mode of operation for other messages from the subscriber station through the alternate backhaul to the destination. The subscriber station is communicatively coupled to the base station and further communicatively coupled to relay station.

Abstract: A method for managing scanning of a plurality of channels in a wireless network is disclosed. The method comprises detecting by a station that a first channel in a plurality of channels is being used for a communication by another station, determining a duration of the communication based upon the communication information, setting a Network Allocation Vector for the station based on the determined duration, scanning a number of channels during the determined duration, and returning to the first channel upon at least one of a) completion of the step of scanning and b) an end of the determined duration.

Abstract: A method for transmitting beacon transmissions in a wireless local area network (WLAN) communications system (100) operating on one or more channels includes transmitting a first beacon (C1) using a directional antenna in a first direction (D1) on a first channel. A second beacon (C2) is then transmitted using a directional antenna in a second direction (D2) on the first channel. This process is then repeated such that the first beacon and second beacon after a predetermined beacon interval. The first beacon begins its transmission at a target beacon transmission time (TBTT) and the second beacon begins its transmission in a sequential period defined by an antenna switching time after the transmission of the first beacon.

Abstract: A method and apparatus for calculating a location of a device is provided. A likelihood of the device being located at a particular location point or a particular location floor is determined using a likelihood calculation at each of a plurality of locations. The location point or location floor is then identified as that location having an associated highest likelihood calculation. The likelihood calculation includes calculating a distance from the device to each of a plurality of reference routers including one or more virtual coplanar reference routers, wherein each of the one or more virtual coplanar reference routers comprise a projection of a non-coplanar reference router onto the floor.

Abstract: A system and method for enabling a mobile user terminal in an ad-hoc packet-switched wireless communications network to selectably operate as a router for other mobile user terminals in the network based on certain criteria. The user terminal comprises a transceiver and a controller. The transceiver is adapted to transmit wireless communications data, such as packetized data, addressed to a destination user terminal, to at least one other user terminal for routing by that other user terminal to the destination user terminal. The controller is adapted to prevent the transceiver from transmitting the wireless communications data to that particular other user terminal based on routing data pertaining to an ability of the other user terminal to route said wireless communications data to the destination user terminal.

Abstract: Energy-efficient discovery techniques are provided for a client node to discover at least one peer provider node in an ad hoc network. For example, the client node can be configured to turn on its first ad hoc interface while in a discovery mode to establish a channel for a first time period. The client node can then transmit a first beacon to advertise its presence to other nodes within the transmission range of the client node to acquire service information from at least one of a plurality of prospective peer provider nodes within the transmission range of the client node. At least one of the prospective peer provider nodes is configured to turn on its second ad hoc interface for a second period of time to listen for beacons from other nodes. The second period of time is less than or equal to the first period of time.

Abstract: A system and method for avoiding collisions between packets transmitted in a wireless network (100). A first node (102, 106 or 107) in the wireless network (100) can transmit a packet to a second node (102, 106 or 107) in the wireless network (100), such that packet includes a header that is transmitted with a higher processing gain than the data, therefore, may be received and processed by a third node (102, 106 or 107. This allows the third node (102, 106 or 107) to detect the transmission of a packet by the first node (102, 106 or 107), which can cause the third node (102, 106 or 107) to avoid transmission of a packet during the transmission by the first node (102, 106 or 107) to avoid collision between the packets. The system and method further enables the nodes (102, 106 or 107) to determine whether they can transmit to another node (102, 106 or 107) based on estimates of interference conditions that can be experienced due to the presence of other nodes (102, 106 or 107).

Abstract: A system and method for calculating a routing metric that can select the route providing the best throughput in a multihopping network (100), based on one or more parameters including completion rates, data rates, MAC overhead and congestion. The system and method are capable of selecting a route in a multihopping network (100) having a high throughput, comprising calculating a routing metric at one or more nodes (102, 106, 107), wherein the routing metric enables the one or more nodes (102, 106, 107) to select the route in the network (100). The routing metric can include network information such as the raw data rate, the completion rate, and the media access control overhead and congestion.

Abstract: A system and method for medium access control (MAC) protocol which controls transmissions in wireless devices to at least substantially comply with specific absorption rate (SAR) limits. The system and method of MAC protocol uses “source-based” time averaging measurements of transmitter “on-times” and an integral of transmission power to direct transmitter duty-cycle such that SAR limits are met. The system and method monitors and controls topology-dependent functions of a node transceiver, including transceiver duty cycle, transceiver transmit power levels and transceiver power-time products, using a automatic transmission control protocol (ATP) to vary functions to maintain specific absorption rate (SAR) limits for handheld and portable devices which are used close to human bodies. In cases in which SAR limits are approached, the ATP can direct the transceiver at the device to adjust each function, or combination of functions, to maintain an acceptable SAR limit.

Abstract: Provided is a system and method for a multicast routing algorithm to work in infrastructure based mesh networks. It chooses access points, fixed infrastructure gateway nodes connected to each other and/or the global internet via a wired/wireless backbone, as a group of local multicast group leaders to form a multicast group leader cloud. Each local multicast group leader is elected on-demand according to the local multicast group member's request. Each local multicast group leader forms a local multicast tree rooted at this leader connecting all multicast group members associated with the AP. The processes of electing and maintaining local multicast trees rooted at APs enable efficient coordination with underlying unicast routing to exploit the advantages of fixed infrastructure nodes. Therefore, routing overhead and multicast tree convergence time are reduced. The method can support large networks with fast topology change due to fast convergence and reduced routing overhead.

Abstract: A system and method for improving the performance of an on-demand routing protocol in a wireless network is provided. The invention provides improved system performance of a wireless network by enabling nodes following an on-demand routing protocol to process (and possibly reply to) route request messages multiple times based on the routing metrics.

Abstract: An alerting system (202) for a communication device (100) is provided. The alerting system is designed to operate in a plurality of operating modes. The alerting system includes a transducer (204) and an electromechanical switch (106). The transducer transforms electrical impulses into vibrations. The electromechanical switch couples the transducer to a first component (206) of the communication device in a first operating mode. Further, the electromechanical switch couples the transducers to a second component (208) of the communication device in a second operating mode.

Abstract: A system and method of operation for managing communication routing from a subscriber station to a base station is provided. The method includes establishing a communication link between the subscriber station and the base station; determining a base station signal quality and a base station timing offset from the subscriber station to the base station; receiving by the base station from one or more relay stations an associated relay station signal quality and an associated relay station timing offset from the subscriber station to the base station through each of the one or more relay stations; identifying a best communication route from the subscriber station to the base station; and transmitting from the base station to the subscriber station a timing correction value associated with the best communication route.

Abstract: A method and apparatus for electing broadcast relay nodes (520B, H, M) in an ad hoc network (500). Each node (520A-520O) generates an attribute message including associated parameters. Each node (520A-520O) generates a weighted value (WV) based on the parameters. The WV can be included in the attribute message for that node, can provide a metric for ranking that node to be nominated to be a broadcast relay node, can alternatively provide a probability measure for that node to probabilistically elect itself as a broadcast relay node. The broadcast manager node (520C) receives the attribute messages and elects at least one nominated node as a broadcast relay node (520B, H, M) based on the attribute messages. Each node (520A-520O) can also initiate election of an intermediate broadcast relay node if that node fails to receive a test message within a predetermined time.