Motorola Corporation

Priscilla L Chen

Vernon Anthony Allen

Yan Huang

Robert J O'Dea

Lance Eric Hester

Monique J Bourgeois

Edgar Herbert Callaway, Jr

Qicai Shi

Masahiro Maeda

Matthew R Perkins

Juan Carlos Palacios

Jian C Huang

Oleg Andric

Chung-Chieh Lee

Jiang Huang

An adaptive channel access scheme allows for statistics that are collected to be used to group radio users into subgroups according to the desired statistic. The subgroups then utilize channels, separated by time or frequency, to access the communication system (). The sub-grouping of the radio users is designed to help minimize the chances of channel-access collisions from occurring.

Adaptive channel access scheme

A process for merging and using the Mediation Device Protocol with a network layer protocol. Under the merged protocol, each device joining a network enters into two stages: the Set-Up Stage and the Normal Operational Stage. During the Set-Up Stage, the device identifies its neighbors, builds a neighborhood list, obtains a Logical ID, and picks a parent node in the network. After the Set-Up Stage is complete, the device enters the Normal Operational Stage where it will send/receive control and data messages, invite and help new nodes to join the network, recover from broken links or topology changes, and other normal network operations.

Procedures for merging the mediation device protocol with a network layer protocol

A communication device () determines whether to operate as a cluster head in a network of communication devices (). The device performs a self-assessment regarding its ability to operate as a cluster head based on a formula that assigns weights to factors related to its capabilities and preferably its environment (). The ability of the device is combined with a random value component in determining whether to operate as a cluster head (). In the preferred embodiment, upon assumption of cluster head status, the device communicates with neighboring devices to signal its cluster head status, and to invite others to participate in the formation of a cluster.

Method and apparatus for a communication network with nodes capable of selective cluster head operation

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 network protocol for low-cost, low-power devices coupled to a self-organizing wireless network using a spanning tree backbone architecture is described. In this protocol, physical and logical network construction and maintenance operations, which supports efficient data routing in the network, are performed. The construction phase in conjunction with the maintenance phase insures the self-organizing capability of the network. At the same time, the maintenance operations provide a self-healing mechanism so that the network can recover from node failures and a self-updating mechanism so that the network can expand as more nodes enter the system. Also, the logical backbone hierarchy will facilitate multi-hop communication. The construction of a logical layered spanning tree backbone architecture from an underlying physical topology allows seamless data communication routing between all nodes in the network.

Protocol for self-organizing network using a logical spanning tree backbone

The invention provides methods ( ) for organizing and assigning network address to network nodes in clusters ( ), and forming new clusters and also provides a method for routing messages in clusters. According to the invention, clusters are organized into hierarchical tree arrangements, with addresses assigned in a manner that facilitates routing messages.

Network architecture, addressing and routing

A system and method for establishing a network within a plurality of interconnected and randomly geographically located nodes, such as wireless devices. One or more cluster heads are selected within the nodes and selectively communicate with the other cluster heads and nodes. The cluster head can be a wireless device or a specific dedicated device such as a router. Each cluster head determines the geographical location of that cluster head and the data-dependent nodes of the cluster head, and selectively receives and stores location information of the other cluster heads and dependent nodes to create an optimal data-routing network within the plurality of nodes.

Network protocol for wireless devices utilizing location information

A contention resolution method includes the steps of determining a contention has occurred and requesting contention resolution from radios in the system ( ). Radios in the system receive the request and do not transmit in the next control frame ( ). Group leader radios ( and ) transmit the identification code they were able to demodulate in the previous frame to the master radio ( ). The master radio ( ) receives the information from the group leaders and transmits a control-channel access message to one of the contending radios ( ).

Growing community of inventors

Sunrise, FL, United States of America

Priscilla L Chen