304 results about "Single hop" patented technology

Interference, collisions, power control, and spatial reuse constitute important issues that need to be resolved urgently in multihop wireless networks such as ad hoc networks, single-hop / multihop wireless LANs, sensor networks, and mesh networks. A method called the evolvable interference management (EIM) method is disclosed in this patent for avoiding / preventing interference and collision and increasing network throughput and energy efficiency in wireless networks. EIM employs sensitive CSMA / CA, patching approaches, interference engineering, differentiated multichannel, detached dialogues, and / or spread spectrum techniques to solve the interference and QoS problems. Also, EIM embodiments based on collision prevention without dialogues are capable of collision reduction / control and can resolve several important problems encountered in previous MACP or RTS / CTS-based protocols, while improving / retaining their important advantages.

The invention concerns routing, scheduling, and power control methods for single and multi-hop wireless networks. A multi-hop network is one in which source and destination nodes may communicate directly or through relay nodes. Nodes in single hop networks communicate without use of relay nodes. Embodiments of the invention may produce an optimal schedule to provide for the best-case goal for a given parameter. In a preferred embodiment, total power is the parameter and total power is minimized for the network. In another preferred embodiment, data throughput is the parameter, and throughput is maximized for the network.

A unified networking device communicates directly with storage devices and servers in the data center and communicates directly with switches and routers outside of the data center environment. The unified networking device manages data transfers between storage devices, between a storage device and a server, between a storage device and a web switch, and between a storage device and a router. The unified networking device is configured to perform data transfers while bypassing a server. The unified networking device is further configured to perform multi-protocol conversion.

The invention relates to an energy balancing wireless sensor network clustering method, which comprises the following three steps of: selecting cluster heads, building a cluster and transmitting data, wherein in the process of selecting the cluster heads, the priorities of nodes to be selected as the cluster heads are set by parameters such as the energy of the nodes, the number of neighboring nodes and the like, so that the cluster heads are more uniformly distributed; in the process of building the cluster, an energy threshold is set as the rebuilding condition of the cluster, so that the aim of reducing the rebuilding frequency of the cluster is fulfilled; meanwhile, a single-hop and multi-hop combined data transmission model is adopted, so that hot problems in a network are solved. Bythe method, the energy can be effectively utilized, the stability of the network is improved, the energy consumption of the network can be balanced, the service life of the network is effectively prolonged, and the network has higher extensibility and safety.

A wireless sensor network routing method based on energy equalization and distance cooperation relates to data fusion and routing technique of wireless sensor network, and is typically used for clustering routing technique. According to a given regulation, the sensor nodes in the wireless sensor network are divided to cluster head node, relay node and cluster member node. The energy consumption of whole wireless sensor network is fully equalized and the effective usage factor of energy is increased. An energy threshold LT is introduced for realizing the smooth transition of roles between nodes, saving the cluster generation time and reducing the energy consumption. Single-hop communication is adopted in the cluster. Direct sequence spread spectrum is applied. Each cluster uses a unique cluster spreading code. All nodes in the cluster use the unique cluster spreading code for transmitting data to the cluster head and the inter-cluster interference is effectively reduced. The method of the invention can obtain purpose of prolonging the survival time of network under the precondition that the information data is reliably, effectively and accurately transmitted to the base station.

The invention discloses an access method of a cognitive wireless MESH network, comprising the following steps of: dividing the wireless network into a multi-layer structure; selecting a cluster head of each single-hop cluster, and taking each cluster head of the same layer as a node of each single-hop cluster of the upper layer thereof until the highest layer; and finishing negotiation between every two transceiving nodes through a common control channel, and locking channel communication through the negotiation. The invention also discloses a control method of the cognitive wireless MESH network, and in the method, each node generates and maintains a data channel priority information table and a neighbor node communicating table; each transceiving node broadcasts and updates information on the corresponding common control channel; and communication is carried out on the channel in a DATA-ACK-DATA-ACK mode. The control method has the advantages that a data transmission channel between every two transceiving nodes can be flexibly matched; interference of a neighbor node is overcome; channel dynamic switch is implemented according to channel quality information; the business demands of a cognitive user is satisfied, and the priority of the user is guaranteed; and self-adaptation loading and regulation are carried out according to the variation of cognitive nodes.

A method for enabling encrypted communication to be performed directly in a single hop or merely directly between two terminals of a mobile radio network by satellite and / or of the GSM / DCS type, after one of said terminals has called via a fixed radio station of the network. After a first encryption stage, performed in conventional manner, a cipher key is simultaneously generated by the identity card associated with the calling terminal and by the network control structure for encrypting / decrypting data transmitted over the radio link between said calling terminal and the station. This cipher key is then stored in a memory of the station so as to be transmitted to the called terminal when a radio link is set up between said station and said called terminal for the call requested by the calling terminal, and the key is used for the purpose of encrypting / decrypting the data interchanged between the calling and called terminals.

A system and method of building a routing table for use in a multiprocessor computer system having a plurality of processing nodes and physical communication links interconnecting the processing nodes in a predefined topology. The system determines all single hops for each processing node, queries each adjacent node for its single hop routes, determines if all nodes can be reached and if all nodes cannot be reached, sets x=2. The system then queries each adjacent node for its “x” hop routes, eliminates all routes to a particular node that are longer than existing routes from the node where the routing table will reside to that particular node, eliminates all routes that introduce a cyclic dependency and chooses a best route for the node. The process is repeated as needed until all nodes can be reach all other nodes.

The invention provides an LEACH protocol improvement method capable of lowering energy consumption. A basic system comprises normal nodes, cluster header nodes, forwarding nodes and a base station. The specific cycle operation steps comprise network topology determination, initialization, selection of the cluster header nodes, cluster forming, data transmission, selection of the cluster header nodes and cluster forming. According to the defects of an LEACH protocol, improvement is conducted from the aspects of selection of cluster heads, cluster forming and a data transmission mode. In selection of the cluster heads, the comprehensive influences of the energy of the nodes, the distance to the base station and density are considered, the burdens of the cluster heads are balanced, and distribution and energy consumption of the selected cluster header nodes are made balanced in a network. In cluster forming, the mode of grid clustering is used, the nodes calculate the two-dimensional values of grids where the nodes are placed by themselves, and the effectiveness of node energy is guaranteed. In data transmission mode, a routing mode with single-hop and multi-hop combined is used according to the distance of the cluster header nodes and the base station, the energy consumption of network nodes is lowered by the purpose that the energy utilization rate is highest.

The invention provides a forwarding method used for constructing multi-hop routing in a wireless self-organizing network, which is based on an ARP proxy system and a mixed routing system. The method comprises the following steps that: a monitoring module of each node monitors each message sent and received by the node in real time; adjacent hosts interact respective routing information in a single-hop range in real time; each node stores a partial or complete topology table of the whole network; when a certain node of the network sends an ARP request to a node which is not directly connected with the certain node, the certain node searches for a next-hop node and sends a routing detection message to the next-hop node according to a routing list; and if the route is reachable, the detection message is transmitted to a target node step by step and returns a routing reachable message, and ARP proxy tables are arranged at various nodes along the route, so a multi-hop route is established. The invention also comprises a method for maintaining and updating the route through modification of network topology detection. The invention also comprises a device used in the network, and describes a complete communication system shown in graph 1.

The invention relates to a networking topologic structure of fleet formation and a design method for a combined multi-address system, belonging to the technical field of the aviation data link, radio navigation and aircraft automation. The invention provides a multi-address system and a networking topologic structure for networking communication and measurement of fleet formation, meets the passive detection and location and the cooperative attack task of the fleet formation to the moving-target. The invention provides the networking topologic structure which can realize the combined multi-address system and support the fleet formation on a DSP (Digital Signal Processor), an FPGA (Field Programmable Gate Array) apparatus and a radio frequency channel on an intermediate-frequency signal processing circuit board of a fleet link terminal. The invention provides two novel multi-address access systems of communication topologic configuration, namely the CDMA Code Division Multiple Access) / FDAM combined multi-address communication system of the fleet formation based on cross-link networking topology and a graded hierarchical multi-address communication system of the fleet formation based on tree topology. The former can support a single-hop access mode of total network coverage and the latter provides a multiple-hop access mode of total network coverage.

The present invention discloses a method and a base station for allocating bandwidth for subscriber stations and a backhaul station through taking into joint consideration uplink and down bandwidth requests from respective subscriber stations in a wireless single-hop self-backhaul network. Upon receipt of information on bandwidth requests from the subscriber stations, the base station takes uplink and downlink bandwidth requests into joint consideration, allocates bandwidth for the subscriber stations and the backhaul station, and then notifies the subscriber stations and the backhaul station. Since bandwidth allocation is no longer based on uplink and downlink resources separately, a relatively high system bandwidth utilization ratio can be achieved and uplink and downlink bandwidth fairness for asymmetric traffic be ensured even if the network is overloaded.

The invention relates to technologies for industrial wireless networks, in particular to a method for precisely synchronizing time of an industrial wireless network on the basis of prediction and compensation. The method includes constructing the factory-automation-oriented industrial wireless network into a star network on the basis of an IEEE (institute of electrical and electronics engineers) 802.11 single-hop basic service set (BBS) structure; setting a master clock and slave clocks according to types and functions of nodes in the industrial wireless network; enabling a master clock side and slave clock sides to interact with one another via two-way timestamp information and computing a time deviation value of a current synchronizing cycle; predicting a time deviation value of a next synchronizing cycle by the aid of the time deviation value of the current synchronizing cycle; compensating clock drift by the aid of the predicted time deviation value of the next synchronizing cycle and correcting the clocks. The method has the advantages that the method is implemented on the premise that application requirements of factory automation are sufficiently considered, so that high time synchronization precision can be realized by the aid of few wireless communication resources, and purposes of high precision, high efficiency, low expenditure and easiness in implementation can be achieved.

A method is described for routing network traffic based on distance information to provide multiple paths that need not have equal costs. The routing algorithm MPATH of the present method provide loop-free routing at every instant, without the need of internodal synchronization which spans more than a single hop. Paths are computed using shortest distances and predecessor information in the routing computation. The use of multiple-successors allows for load-balancing within the network. The algorithm is both distributed and scalable to large networks due to its use of only one-hop synchronization. A number of procedures are described by way of example, including path computation, main table updating, neighbor table updating, and a multipath (MPATH) algorithm.

The invention provides a method for precisely synchronizing a wireless sensor network under a coal mine, which relates to the field of the precise synchronization of wireless sensor networks and solves the problem that the precise synchronization of the wireless sensor network under the coal mine is very difficult to achieve. The synchronization method is implemented by the following steps that: A, a central station host computer sends configuration information to each cluster head node of the wireless sensor network; B, the cluster head node receives the configuration information sent by thecentral station host computer, then performs time synchronization of an ethernet LAN and sends a synchronization command to a mobile node in the wireless sensor network; and C, the mobile node performs synchronization with the cluster head node. The method adopts an IEEE1588 synchronous protocol to finish the nanosecond synchronization of the ethernet LAN, adopts a single-hop TPSN synchronized algorithm to avoid the synchronization error accumulation, and is suitable for solving the precise synchronization problems of the wireless sensor network under the coal mine, and is also used for solving the synchronization problems of the combination of all ethernet LANs and wireless sensor networks.

The invention provides an inhomogeneous clustering multihop wireless sensor network routing protocol based on energy balance. A wireless sensor network data transmission method comprises the followingsteps: voting a cluster head according to residual energy of the nodes, the distances from the nodes to a base station and the distances from the nodes to the cluster head, separately adding the nodes not becoming the cluster head to the cluster where the cluster head having the shortest distances with the nodes is located; then, constructing, by the cluster head, an optimal transmission path based on a minimum spanning tree according to the residual energy and the distance to the base station so as to find the optima next hop forwarding cluster head; and finally transmitting data to the basestation by the nodes in a single hop in the cluster and a multihop communication mode between the clusters. By adoption of the method, the energy of the nodes can be effectively saved, the energy consumption of the nodes can be balanced, and thus the life cycle of the wireless sensor network is prolonged.

The invention relates to a wireless sensor network protocol based on institute of electrical and electronic engineers (IEEE) 802.15.4. A central coordinator and at least one terminal node form a star network, each terminal node establishes connection with the central coordinator through a single hop to realize dual-way transmission of wireless data, each terminal node and the central coordinator are in line with a communication protocol, a communicated superframe comprises a plurality of time slots with equal set time, a first time slot when the superframe starts is a beacon frame when the central coordinator starts to broadcast to outside, time synchronization among the terminal nodes in a network is realized by monitoring the beacon frame, thereafter the terminal nodes realize dual-way communication with the central coordinator in two pre-distributed adjacent time slots according to a time sequence, the terminal nodes are in dormant and waiting states after communication and wait for being woken by an initial beacon frame of the central coordinator. The wireless sensor network protocol has the advantages of simple structure, dual-way data transmission, high reliability, determined communication time and the like, the packet transmission rate is high, and the power consumption of the nodes is low.

In a cellular wide-area radio communications system, comprising a plurality of base stations; a plurality of relay stations; and a plurality of mobile stations; wherein each of the relay stations is associated with at least one of the base stations, each of the mobile stations is associated with at least one of the base stations or one of the relay stations, wireless data transmissions between mobile stations and base stations take place either as single-hop data transmissions between the mobile stations and their associated base stations, or as multi-hop data transmissions between the mobile stations and their associated relay stations and a data transmission between the relay stations and base stations associated with the relay stations, and wherein an average number of multi-hop data transmissions in the radio communications system equals at least an average number of single-hop data transmissions.

A system and method for improving communication between two user terminals in a telecommunication system is disclosed. When two user terminals, such as in a satellite-based system with a terrestrial network interface, switch from a double-hop connection with the network to a single-hop connection with each other, communication is established according to the present invention by synchronizing the protocol parameters between the two user terminals, which in the double-hop connection were separately synchronized with the network.

A novel single-hop WDM network, the AWG∥PSC network, comprises an AWG in parallel with a PSC. The AWG and PSC provide heterogeneous protection for each other; the AWG∥PSC network remains functional when either the AWG or the PSC fails. If both AWG and PSC are functional, the AWG∥PSC network uniquely combines the respective strengths of the two devices. The throughput of the AWG∥PSC network is significantly larger than the total throughput obtained by combining the throughput of a stand-alone AWG network with the throughput of a stand-alone PSC network. The AWG∥PSC network provides, over a wide operating range, a better throughput-delay performance than a network consisting of either two load sharing PSCs in parallel or two load sharing AWGs in parallel.

The invention discloses a node energy consumption balancing method for a wireless sensor network. The method includes the steps of 1, acquiring the distance from each node in the network to a base station; allowing the base station to calculate optimal hop count and optimal cluster number according to the network scale, and allowing each node in the network to calculate the distance from itself to the base station; 2, determining an energy threshold of the current cycle; 3, establishing clusters, namely reserving each candidate cluster head have residual energy larger than the energy threshold as a cluster head, and adding non-cluster-head nodes to different clusters; 4, transmitting stably, namely allowing the nodes in each cluster to transmit data to the cluster head in a single hop manner, and allowing the cluster head to forward the data to the base station in a combined manner of single hop and multiple hops. The node energy consumption balancing method for the wireless sensor network has the advantages that energy consumption is balanced for the nodes and the service life of the network is effectively prolonged.

The invention discloses an annulus-based node energy consumption balancing method in a heterogeneous sensor network. The method comprises the following steps of: determining the cluster head level by dividing a monitoring region by rings, and arranging two types of sensor nodes with different hardware configurations in the sensor network, wherein the cluster head uses a communication mode with optimal single hop and multi-hop proportion. In the method, a sensor node energy consumption model is used, based on the difference of the energy consumption increasing speeds when transmitting data packets for different distances, and in combination with the disadvantages and advantages of the single hop and multi-hop communication modes, the single hop and multi-hop optimal proportion related to the radius of the monitoring region in a cluster head mixed communication mode is obtained, the load on the node is balanced, and the lifecycle of a wireless sensor network is prolonged effectively.

The invention discloses a wireless sensor network data transmission method based on an LEACH protocol and belongs to the technical field of wireless sensor networks. The method aims at balancing the energy consumption of sensor nodes and prolonging the life cycle of a wireless sensor network. In order to overcome the defects of the LEACH protocol, the LEACH protocol is improved in the aspects of cluster head selection and data transmission. In each round of cluster head selection, the nodes are classified into a standard zone and a warning zone according to remaining energy, so that the nodes located in different zones are selected as cluster head nodes of the round at different probabilities, and therefore the nodes with relatively low energy are protected. In the data transmission process of cluster heads and a base station, according to the distances between the cluster head nodes and the base station, data transmission is conducted in a single-hop and multi-hop combined mode, and energy expense is reduced. According to the method, the life cycle of the network is effectively prolonged, the energy consumption of the network is balanced, and the performance of the network is optimized.

The invention belongs to the technical field of mobile communication and relates to a message broadcast-oriented MAC (Media Access Control) layer improving method in an VAENT (Vehicular Ad-hoc NETwork). For a stream media message, an RTB / CTB (request-to-broadcast / clear-to-broadcast) mechanism is used to select a relay vehicle; an ARC-SMB (Adaptive Rate Control-Streaming Media Broadcasting) method is provided in order to guarantee the smoothness of receiving stream medium data by a user; according to a detected channel transmitted data frame state, a broadcast vehicle adjusts data transmitting speed, so that the packet loss rate is reduced; the concept that the user manually adjusts the quality required by a stream media is provided in order to improve the user experience. The state of broadcasting a safety message in an actual environment is simulated, so that the vehicle acquires better delivery rate, single-hop delay is reduced, and the load rate is reduced; the broadcasting state of the safety message in the actual environment can be simulated by the ARC-SMB method, so that the vehicle acquires better delivery rate, the packet loss rate is reduced, and more smooth stream media transmission is provided for the user.

The invention discloses a satellite mobile communication system based on partial satellite baseband switching, which belongs to the technical field of satellite communication. The satellite mobile communication system comprises a communication network body branch and a satellite switching management control branch which are discrete and parallel. A management control signal of satellite switchingprocessing is produced and transmitted by the satellite switching management control branch. A satellite processor in the system has the complete function of satellite transparent forwarding between a user link and a feeding link and also supports partial communication business for realizing satellite single-hop connection in the mode of bridging a bypass. A communication interface, a protocol specification and a processing course of the prior ground mobile communication system are not corrected basically; the prior scheme of the ground user terminal can be directly adopted by a satellite user terminal without considering double-module / multiple-module terminal design requirements; and simultaneously, the satellite mobile communication system is convenient for the further upgrade of a communication network body of the satellite system along with the development of the network technique of the ground mobile communication system.

A network system with a STAR topology allows single hop connectivity between sites. The system has a hub site and a plurality of remote sites. A first channel is used for sending data from the hub site to all of the plurality of remote sites. A plurality of second channels are used for transmitting data from each of the plurality of remote sites to the hub site and for transmitting data between the plurality of remote sites. In the system, call control and management between the hub site and the remote sites and between different remote sites use Internet protocol (IP) addressing for identification.

Use of a Location ID in addition to normal information to allow development of non-shortest path routes. The edge switches which terminate the distance links between locations are identified. Shortest path routes are determined for all switches in the same location. For each edge switch, routes over the distance links to other locations are determined, marking the interface connected to the distance links. The two determined sets of routes are combined. For devices directly connected to the edge switch, only the marked interface is used to reach the other location. For switches directly connected to the edge switch, use only routes from non-marked interfaces to marked interfaces and remove any routes from marked to marked or non-marked to non-marked interfaces. This operation for the directly connected switches allows single hops that are non-shortest path to an edge switch and removes certain potential loopback situations due to shortest path routes.

The invention discloses a crop growth monitoring platform based on the Internet of Things. The monitoring platform comprises N remote data acquiring sites, at least one remote data sending terminal, a remote data storage server, a crop growth monitoring center and a monitoring data browsing terminal, wherein N is the natural number greater than and equal to 1; each remote data acquiring site is connected with the remote data sending terminal in a wire or wireless way; the remote data sending terminal is used for uploading the environment information data of the crop growth acquired by the remote data acquiring site to the remote data storage server; the remote data storage server is respectively communicated with the crop growth monitoring center and the monitoring data browsing terminal; the monitoring platform is used for uploading and feeding back the environment information data by networking in a single-hop or multi-hop way.

The invention discloses an unmanned aerial vehicle ad hoc network routing method based on link stability. The link stability is jointly determined by unmanned aerial vehicle node relative speed, single-hop link transmission delay, single-hop link signal intensity and link active time. On the basis that a link life cycle is used as a routing selection restriction parameter, the effect of rapid change of unmanned aerial vehicle cluster topology on routing can be reduced to a large extent, the routing failure frequency can be reduced, and the routing stability can be improved. Meanwhile, as a routing core algorithm is deployed in a centralized server, the operation performance is higher than that of traditional distributed routing operation. A cluster controller maintains all link states of a cluster, the backup path can be selected rapidly in case of a routing failure event, and the requirement for rapid response of routing is met.

The invention discloses a task allocation algorithm in a wireless sensor network based on node property. The task allocation algorithm is a method for constructing task processing property parameters of a node according to energy consumption, speed, success rate and other factors in task processing of the node. The method comprises the following steps: constructing a single-hop wireless sensor node model; dividing a task into a plurality of task groups based on a task relational graph; calculating the property parameters of each node; and selecting an allocating scheme with the best sum of the property parameters. The task allocation algorithm has the beneficial effects that a task grouping method is utilized to realize parallel processing and real-time response of the task and reduce communication energy consumption at the same time; the calculation energy consumption and the communication energy consumption in task processing of the node are formulized, all factors influencing the task processing of the node are comprehensively considered, and an optimal method is utilized to construct a property parameter; and node properties are quantified, thereby simplifying a task allocating strategy, simply and conveniently finishing the task allocation and realizing the high efficiency of system energy and the real-time response of the task.