Abstract:
A wireless movable device, a system comprising the movable device, and a method for operating the movable device, wherein the movable device determines the link and channel quality of a link between itself and an ad-hoc device, such that the movable device is adapted to determine when it has traveled too far from the ad-hoc device to maintain a reliable link to the ad-hoc device, and wherein the movable device, upon determining the loss of a reliable link to the ad-hoc device, seeks out a location at which a reliable link exists with the ad-hoc device or with another ad-hoc device.
Abstract:
A system and method for deploying a network of wireless devices, including mobile terminals, wireless routers and at least one control console, within a three dimensional deployment area such as building, so that communication, identification and position calculations of personnel, such as firefighters, using the mobile terminals can be achieved regardless of building structure, and so that a user can determine whether tracked assets, such as firefighters in a fire and rescue scenario, have remained within predetermined user-designated areas for longer than a desired period of time, so that an alarm can be generated which identifies the subject assets and the locations, such as the floor number of a building, where the subject assets are located.
Abstract:
A first time division multiplex (TDM) time slot (310) is provided which is defined as a bi-directional channel for use in a TDM network (300) including a source node and a destination node. The source node can transmit data to the destination node in a first portion (320) of a first TDM time slot. In one implementation, a second portion (320) of the same first TDM time slot can be reserved for the destination node to transmit information to the source node. For example, the destination node can determine whether the data from the source node has arrived properly, and then transmit an indication message to the source node in the second portion of the same first TDM time slot to indicate whether the data from the source node has arrived properly at the destination node (330).
Abstract:
Techniques are provided for communicating a data stream in a wireless communication network. A source divides the data stream into a first data sub-stream and a second data sub-stream. The first data sub-stream can be modulated using a first modulation technique to generate a first modulated data sub-stream, and the second data sub-stream can be modulated using a second modulation technique to generate a second modulated data sub-stream. A destination receives the first data sub-stream over a first frequency band, and receives the second data sub-stream over a second frequency band. The destination demodulates the first data sub-stream using a first demodulation technique to generate a first demodulated data sub-stream, and demodulates the second data sub-stream using a second demodulation technique to generate a second demodulated data sub-stream. The destination then combines the first demodulated data sub-stream and the second demodulated data sub-stream to generate the data stream.
Abstract:
A system and method for increasing the capacity of a wireless network (100, 300) including a plurality of access points (APs) (106, 305) and a plurality of nodes (200), at least one of said nodes (200) and at least one of said APs (106, 305) including multiple radios (310), the method comprising: (i) determining the routing metrics to one of said APs through each radio interface that is common between one of the nodes and that AP; (ii) selecting the radio interface whose routing metrics meet a desired criteria for packet stream transmission between the at least one node and the AP; and (iii) transmitting at least one packet stream from the node to the AP through the selected radio interface.
Abstract:
A first time division multiplex (TDM) time slot is provided which is defined as a bi-directional channel for use in a TDM network including a source node and a destination node. The source node can transmit data to the destination node in a first portion of a first TDM time slot. In one implementation, a second portion of the same first TDM time slot can be reserved for the destination node to transmit information to the source node. For example, the destination node can determine whether the data from the source node has arrived properly, and then transmit an indication message to the source node in the second portion of the same first TDM time slot to indicate whether the data from the source node has arrived properly at the destination node.
Abstract:
A system and method for automated visual tracking of assets (302), such as personnel or vehicles, using location measurements and ad-hoc routing algorithms employed in a wireless multihopping communication network (100). The system and method comprise a plurality of imaging devices (300) that are deployed about an area and provide image information to at least one workstation (304) that displays the images based on the image information. In particular, as an asset (302) moves, the workstation (304) switches from displaying an image of the asset (302) captured by an imaging device (300) away from which the asset (302) is moving to displaying an image of the asset (302) captured by an imaging device (300) toward which the asset (302) is moving.
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 system and method for providing a traffic control scheme for QoS provision and congestion control across multiple interfaces of wireless nodes (102, 106 and 107), such as wireless access points (107 and 106), communicating in a wireless multihopping communication network (100). The nodes (102, 106 and 107) can include multiple transceivers. The system and method detects bottleneck interfaces in these nodes (102,106, 107) to control the traffic along the path of the corresponding traffic flow. Different measurements and cross-layer feedback are used to differentiate the cause of the congestion, such as wireless link quality degradation due to fading or degradation due to congestion in a shared medium. The nodes (102, 106, 107) inform each other on the status of their congestion level. High and low level signaling and interruption mechanisms are used to control the interfaces of the congested node (102, 106 or 107) to adjust traffic flow and alleviate the congestion.
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).