Abstract:
A data transmission method is provided. The method includes: receiving from a plurality of receiving stations, which include base stations and relay stations, a state information value corresponding to the receiving stations; measuring signal strength with respect to the receiving stations; selecting any one receiving station from among the receiving stations which have a great signal strength value obtained by measuring the signal strength and which have a small state information value; and transmitting data to the selected receiving station. Accordingly, radio resources can be prevented from ineffective use caused by relay transmission.
Abstract:
A method (400) and system (100) for a wireless multi-hopping communication system is provided, wherein the system (100) includes an access point (102), a source node (CR1), and a plurality of nodes. The source node (CR1) is in communication with the access point (102), and configured to transmit a signal on at least one of a plurality of frequencies. The plurality of nodes are in communication with the access point (102) and the source node (CR1), and configured to transmit a signal on at least one of the plurality of frequencies, wherein the source node (CR1) and the plurality of nodes are adapted to determine a routing path utilizing at least one intermediate node (CR2) of the plurality of nodes and a transmitting frequency of the plurality of frequencies while reducing interference to a primary user of the transmitting frequency.
Abstract:
There is provided a method for optimal data transmission for improving a data transmission rate of a node with variable transmission power in a multi-hop wireless network, the method including the steps of: obtaining channel state information about a current wireless channel of the node; calculating a carrier sensing range in the number of hops using the obtained channel state information, a target signal-to-interference ratio, and a contention window size in order to minimize data collision; calculating the number of nodes attempting data transmission based on signals received from neighbor nodes, the number of the nodes attempting data transmission being the number of contention nodes; and setting transmission power adaptively according to the calculated carrier sensing range value and the contention node numbers and transmitting data with the set of transmission power.
Abstract:
A control system uses a wireless network to provided communication between a host computer and field devices. The field devices are normally maintained in a lower power or sleep state. Only field devices that will be involved in a communication with the host computer are turned On and maintained On until communication between the field devices and the host computer is completed.
Abstract:
A control system uses a wireless network to provide communication between a host computer and field devices. The host and the field devices communicate with one another using control messages and response messages based upon a known control system protocol. The control and response messages are embedded as a payload within a wireless message that is transmitted over the wireless network. When the wireless message is received at its ultimate destination, the control or response message is separated from the wireless message and is delivered to the intended recipient (either a field device or the host computer).
Abstract:
A control system uses a wireless network to provide communication between a host computer and field devices. The host and the field devices communicate with one another using control messages and response messages based upon a known control system protocol. The control and response messages are embedded as a payload within a wireless message that is transmitted over the wireless network. When the wireless message is received at its ultimate destination, the control or response message is separated from the wireless message and is delivered to the intended recipient (either a field device or the host computer).
Abstract:
By introducing a novel parameter common to all links along the entire multihop route it is possible to more flexibly allocate, for each of a number of the links, a set of three interdependent link transmit parameters representative of a) link transmit energy, b) link transmit time or link transmit bandwidth or link code word consumption, and c) link transmit power. Basically, the common parameter is determined based on a given end-to-end (ETE) transmit parameter constraint for the entire multihop route (S 1). The idea is then to assign or allocate, for each considered link, the three interdependent link transmit parameters based on the common parameter and local link characteristics (S2). In this way, all three link transmit parameters may (and generally will) be different between at least two links on the route when the links have different link characteristics, assuming that each link transmit parameter is also dependent on the local link characteristics. Preferably, the common parameter is determined in the process of optimizing a given objective ETE function.
Abstract:
A route discovery device and method in a mobile ad-hoc network. The route discovery device and method seamlessly maintain a route for providing service by establishing the service route while taking into account the efficiency of energy of a terminal in the mobile ad-hoc network. A mobile host broadcasts a service request message. One of relay hosts of the mobile hosts selects a service request message, calculates power information of the mobile host, includes the calculated power information of the mobile host in the power information included in the selected service request message and re-broadcast the service request message. A destination host of the mobile hosts selects a service request message, generates a service response message and transmits the service response message along a route of the selected message.
Abstract:
The performance and ease of management of wireless communications environments is improved by a mechanism that enables access points (Aps, 12) to perform automatic channel selection. A wireless network can therefore include multiple Aps (12), each of which will automatically choose a channel such that channel usage is optimized. Furthermore, APs (12) can perform automatic power adjustment so that multiple AP (12) can operate on the same channel while minimizing interference with each other. Wireless stations (16) are load balanced across Aps(12) so that user bandwidth is optimized. A movement detection scheme provides seamless roaming of stations between Aps (12).