Motorola Corporation

Jian C Huang

Qicai Shi

Spyros Kyperountas

Feng Niu

Yan Huang

Edgar Herbert Callaway, Jr

Lance Eric Hester

Neiyer S Correal

Robert J O'Dea

Matthew R Perkins

Oleg Andric

David F Willard

Frederick L Martin

Floyd D Simpson

Masahiro Maeda

Vernon Anthony Allen

Priscilla L Chen

Wayne W Chiou

Monique J Bourgeois

Padmaja Ramadas

Timothy Bancroft

A method and apparatus for determining a node's proper duty cycle is provided herein. All nodes () within a network () will interactively switch duty-cycles based on a number of hops a device is from a personal area network coordinator PNC. Changing duty cycles based on a number of hops from a PNC assures that spatial patterns of duty-cycles form in a network to maximize data throughput and minimize network wide power consumptions.

Method and apparatus for a node to determine a proper duty cycle within an ad-hoc network

An ad-hoc communication system is established where each node within the system may have multiple children nodes and parent nodes. An address scheme is proposed where each node may comprise more than one address, each address being based upon one of the parent's address. Because each node may have more than one parent, a bridge, or shortcut may exist between network branches.

Method and apparatus for operating an AD-HOC communication system

During operation a node () that has associated with a network () will periodically broadcast a beacon () during a beacon interval as part of a superframe. The beacon will be periodically broadcast for a first period of time, based on a time it takes for nodes to associate with the network. After the first period of time has passed, the beacon will be switched off for a second period of time, after which, the beacon will again be periodically broadcast.

Method and apparatus for operating a node in a beacon based ad hoc network

A low power consumption protocol for low power communication devices attached to an asynchronous network is described. In this protocol, one or more mediation devices (MDs) facilitate data processing capabilities in the network, whether in a dedicated MD or distributed MD network environment. These capabilities may be provided by the functions of packet caching, removal of replicated packets, and multiple communication types performed by the one or more MDs in accordance with a common synchronization schedule () managed by the one or more MDs and communicated to other devices in the network ().

Media access control and distributed data processing using mediation devices in an asynchronous network

Mediation devices in an asynchronous network of low power consumption communication devices are leveraged through the use of new protocols () that analyze relevant QoS parameters () in order to provide a better than best effort service in the network. These protocols invoke adaptive quality of service (QoS) mechanisms to capitalize on the strength and flexibility provided to the network by the presence of one or more MDs, as described above. Expanded functionality of the MD includes control information messaging and service differentiation for the purpose of improving QoS of the network.

Quality of service (QOS) control mechanisms using mediation devices in an asynchronous network

A method and apparatus for determining the path loss model of an object within a wireless communication system is provided herein. During operation, a path loss model for a node is generated based on path loss values and corresponding numbers of neighbors of the said node. The path loss model is used to determine a relationship between path loss and distance. With this relationship established, distances to known-located nodes may be obtained by obtaining a path loss to the known-located node. From these distances, a node can then be located.

Method and apparatus for determining the location of a node in a wireless system

A method for peer-to-peer ranging and discovery of a rigid body existing in a scatternet having piconets and nodes includes the steps of defining a node () in a piconet () to be a piconet controller (PNC) having controller functions, locating a rigid body seed including the node (), and discovering a rigid body by sequentially downloading controller functions of the piconet controller () to at least one border node. Also provided is a communications node including a receiver for receiving communications from other communications nodes in a communications range (R), a transmitter for sending communications to other communications nodes in the communications range (R), a memory storing at least ranging information and a unique identification for describing the node, and a processor connected to the receiver, to the transmitter, and to the memory, the processor being programmed to carry out the method according to the present invention.

Method for rigid body discovery and peer-to-peer ranging in a scatternet and communications node

A method and apparatus for message flooding is provided that takes advantage of the availability of node locations. The transmission of a flood message by a node is based on location information of neighboring nodes. In particular, each node within the communication system will delay retransmission of flood messages by a predetermined amount of time. If, during this delay, a node hears the flood message from a neighboring node (home flooding) or another node (neighborhood flooding), it then cancels transmission of the flood message.

Method and apparatus for message flooding within a communication system

A method for estimating the location of a blindfolded node () in a wireless network having reference nodes () is provided. The reference nodes () are combined into pairs () and each pair is checked to determine if the reference nodes are within each other's communication rage (). A plurality of probable regions () for the blindfolded node are obtained (). These probable regions are overlapped (), and the blindfolded node's estimated location is estimated to be the geometric center of the overlapped regions ().

Method for estimating the location of a wireless device in a communication network

A location technique is utilized within a wireless communication system where power measurements from various nodes are weighted to determine a node's location. An iterative location process is executed where as more and more nodes are heard from, a node will re-locate itself in order to improve location accuracy.

A method and system is provided for determining a location for each of a plurality of units, which are sub-divided into more than one sub-net groupings, that each include two or more units. Within each sub-net grouping, measured range information between units within the sub-nets and one or more reference units is gathered in at least a selected one of the units. The selected one of the units then estimates a location for each of the units, which minimizes any error in the measured ranges between the units in each of the corresponding sub-nets.

Method and system for determining a location of a plurality of units using sub-divided unit groupings

A method for reducing communications in a peer-to-peer wireless network having nodes includes sending an RTS-TOA ranging communication from a first node (N) in a node group to another node (Nr, I) in the group, receiving the RTS-TOA communication with the second node (Nr, I) and sending a multi-cast CTS-TOA/RTS-TOA ranging communication from the second node (Nr, I) as a reply to the received RTS-TOA communication, and successively and sequentially repeating the multi-cast sending step for each of the nodes. A CTS-TOA message is a reply to the received RTS-TOA message and, simultaneously, is an RTS-TOA ranging communication to a new destination node (J). The method applies for a randomized communications approach when node identifications are not sequenced and to a sequential approach where nodes are sequenced, and also applies to completely connected and multi-hop networks. Also provided is a node for carrying out the method of the present invention.

Distributed MAC protocol facilitating collaborative ranging in communications networks

A method and location determination module is provided for determining a location of one of a plurality of units using neighbor lists. Each unit is communicatively coupled to at least some of the other plurality of units, where at least some of the plurality of units are reference units, whose locations are known. The units communicate with other nearby units within communication range, to establish neighbor lists. A unit to be located then identifies an aggregate value corresponding to the number of occurrences of the reference units in the neighbor list of the unit to be located and the neighbor lists of each of a group of associated units. The location of the unit to be located is then determined, based upon the known locations of the reference units and the number of identified occurrences of the reference units in the corresponding neighbor lists.

Method and apparatus for determining the location of a unit using neighbor lists

A cluster tree network formed by self-organization of a number of nodes. The method of self-organization includes processes for cluster formation, cluster network maintenance, intra-cluster communication. In the cluster formation process, each node discovers if any neighboring node is a cluster head or if any node is already a member of a cluster (thus making it a networked node), and if a cluster head or a networked node is discovered, each node establishes a communication link with the cluster head or the networked node. If no cluster head or networked node is discovered, the node itself becomes a cluster head. The network is maintained by each node periodically broadcasting a HELLO message to neighboring nodes, receiving responses to the HELLO message and updating a neighbor list in accordance with responses to the HELLO message. Multi-cluster networks are also provided using the processes of inter-cluster network formation, inter-cluster network maintenance, and inter-cluster communication. The resulting network has one or more clusters of nodes, each with a cluster head and a number of member nodes, each assigned a node identifier by the cluster head. In a multi-cluster network, a designated device assigns identifies to each cluster head in the network. Border nodes, which are members of at least two clusters, act as routers connecting the clusters and relaying information packets between the clusters.

Protocol and structure for self-organizing network

A communication device () operates in a training mode to develop parameters based on estimates related to at least two different instances of channel conditions, such as indicated by bit error rates for channel transmissions (). The parameters are used to define a function that characterizes an optimized throughput or energy consumption per bit through varying channel conditions. The function is preferably of the form a0+a1*Log(1+L), where a0 and a1 are fitted parameters, and Lthe frame size. The device responds to changes in channel conditions by transmitting messages on the communication channel using a frame size adapted for channel conditions based on the particular function and the developed parameters ().

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Lake Worth, FL, United States of America

Jian C Huang