480results about How to "Reliable data transmission" patented technology

A telecommunications system and method for transmitting digital images produced by a digital camera attached to or integrated with a mobile station (MS) from the MS to a receiving terminal through the Internet. A calling mobile subscriber can select the digital image to transmit and dial the number associated with the receiving terminal on the MS. The digital image is then sent in parallel through the Internet while a telecommunications connection, such as a call setup request, is being sent through the cellular or fixed network. At the end office serving the receiving terminal, the call setup request is associated with the digital image and a call connection is established between the calling MS and the receiving terminal. When the call connection is established, the end office serving the receiving terminal sends the digital image to the receiving terminal.

The invention discloses an avionics system suitable for a multi-purpose unmanned aircraft. A 1553B dual-redundancy bus framework is adopted in the avionics system. The avionics system consists of a main processor unit, a universal interface unit, a 1553B bus, a mass memory, an airborne monitoring terminal, a task load, an execution mechanism and a sensor assembly. The devices have the connection relationships that: the main processor unit, the universal interface unit, the mass memory, the airborne monitoring terminal and the task load are connected with the 1553B bus through a 1553B special electric connector, and the 1553B special electric connector serving as a bus module connects all the devices attached to the bus together; a steering engine controller is connected with the universalinterface unit through an RS422 interface; and the sensor assembly is connected to the universal interface unit through interfaces of serial RS422/RS232/RS485, an ARINC429 bus, a CAN, analogue AD/DA and discrete DIO and the like. The avionics system has the characteristics of strong multi-task expandability, multi-redundancy high reliability, rich data interfaces and strong calculation and processing capabilities, and can well meet the application requirement of 'one platform and multiple purposes' of the unmanned aircraft.

The invention belongs to the field of wireless communication, and particularly relates to a self-upgrade method for equipment in a remote online monitoring system. The method is characterized in that: each piece of terminal equipment performs self-upgrade and self-maintenance through the remote online monitoring system consisting of a terminal table tool, a data acquisition unit and a background server based on a GPRS (General Packet Radio Service). The method mainly comprises the following steps that: the background server manages an application program and version information; the data acquisition unit periodically inquires a version log and downloads a new version program; the data acquisition unit realizes self-upgrade and upgrades the terminal table tool; and after the new version program is updated successfully, skipping is performed and an old version program is still kept for later use. In the method, the GPRS, storage space management, a file sub-package mechanism, a transmission response mechanism, a mode for continuous transmission at break-points and an IAP (Internet Access Provider) program programming mode are combined, and the accuracy and reliability of data transmission are ensured; and under the condition of not influencing normal use of a user, the equipment upgrading and maintaining problems of large quantity and wide distribution are solved quickly and efficiently.

The present invention relates generally to acquisition of data from RFID devices (132-136), such as sensor data. Prior art systems of active RFID devices have a problem of high average power consumption, and therefore, the energy source of the RFID devices needs to be replaced or charged frequently. The present invention provides a new solution wherein the RFID device has a power saving mode in which the receiver of the RFID device has a decreased ability to receive/detect RF signals. The RFID device may include a timer which is functional during the power saving mode, and the receiver of the RFID device will turn into active mode at a point of time based on the time value of the timer. Signal strength of an RF channel is indicated with a receiver, and transmission of data is dependent on the indication of the signal strength.

A clock system for a data bus, e.g., a memory bus system, provides a write data (WCLK) clock signal in one direction on a bus and a data read (RCLK) clock signal in an opposite direction on the bus. A predetermined phase relationship between said WCLK and RCLK clock signals is set at a predetermined location on the data bus to ensure that all memory subsystems connected to the bus receive the WCLK and RCLK signals with appropriate timing to ensure proper operation of the memory subsystems.

The invention relates to a multi-path transmission mechanism of a wireless multimedia sensor network and a congestion control method thereof. Based on intensively distributed wireless sensor network nodes and wireless multimedia sensor network nodes, the method aims to improve the quality and reliability of sensor data transmission by establishing a plurality of sensor data transmission paths between a source node and a target node through a relay node to ensure the in-time, accurate and reliable arrival of multimedia sensor data and common sensor data at the target node. Meanwhile, for improving the utilization rate of network resources, the invention provides a method for finding, reporting and regulating congestion in the relay node and the path of the relay node to further ensure the reliability of data transmission.

For the purpose of allowing a sensor device (10) to carry out wireless communication with a server node (11), the sensor device (10) makes an inquiry about the server node (11) connectable to the sensor device (10) (S12). The server node (11) responds to the sensor device (10) (S13). The sensor device (10) transmits a result of the inquiry as a candidate list (S15). The server node (11) transfers the candidate list to a top node (S16). The top node receives key information and selection information selected from the candidate list, and transmits the key information and the selection information to the server node (11) selected (S19). The server node (11) transfers to the sensor device (10) the selection information, the key information, and a building ID and a room ID of the server node (11). The sensor device (10) determines whether the key information received agrees with sensor device key information (S20). When the key information agrees with the sensor device key information, the sensor device (10) notifies, to the server node (11), the agreement and an individual ID of the sensor device (10), and stores the building ID and the room ID (S21). This makes it possible to provide a sensor network system in which a communication path is safely and reliably established even when a different network exists in a communication area and a method of establishing the communication path.

The invention provides a ZigBee-based quadrocopter farmland positioning system which comprises a plurality of known positions, ZigBee beacon nodes at the same height, and to-be-positioned quadrocopter nodes composed of the quadrocopter and ZigBee nodes, and also a positioning method which comprises the steps of selecting four beacon nodes strongest in wireless signal intensity when the quadrocopter flies over the farmland, calculating the spatial distance between the node of the quadrocopter and each beacon node through the intensity of a received wireless signal, mapping the spatial distances into horizontal distances between the node of the quadrocopter and the beacon nodes within the horizontal plane, combining every three beacon nodes to form a triangular positioning subregion and forming 4 subregions in total, for each subregion, calculating the relative coordinates of the quadrocopter by a trilateral positioning method, next, calculating the center of mass of a quadrangle formed by the four pairs of relative coordinates by a center-of-mass method, and then taking the coordinates of the center of mass as the final position coordinates of the node of the quadrocopter. The ZigBee-based quadrocopter farmland positioning system is capable of realizing low-cost, high-precision and fast-positioned regional operation in the farmland.

The invention discloses a multichannel cooperative data transmission method and system. The method of the invention comprises the following steps: a sender sends a cooperative request-to-send (CRTS) packet carrying a data channel number to a receiver through a first control channel; after the receiver receives the CRTS packet, if the acquired data channel is judged to be usable, the receiver returns a conditional clear-to-send (CCTS) packet carrying the highest channel rate between the receiver and the sender to the sender; a candidate cooperative node intercepts the CRTS packet and the CCTS packet, and if the acquired data channel is judged to be usable and the cooperation condition is met, the candidate cooperative node sends a high (HI) packet according to access time delay; if the receiver only receives the HI packet, the receiver sends a relay acknowledgement (RACK) packet on the first control channel to disclose the cooperative node; if the sender receives the RACK packet, the sender sends a data packet to the receiver through the cooperative node; and after the receiver successfully receives the data packet, the receiver returns an acknowledgement packet through a second control channel. The invention can be used to realize efficient and reliable data transmission.

The invention provides an intelligent monitoring system based on a wireless sensor network technology. The intelligent monitoring system comprises monitoring nodes, gateway nodes, a service platform and access terminals, wherein the gateway nodes are in communication connection with the monitoring nodes through a Zigbee wireless network, and used for controlling the monitoring nodes; the service platform is in communication connection with the gateway nodes through a TCP/IP-based network, and used for summarizing data uploaded by the gateway nodes, storing, analyzing, adding up and processing the data, and sending control instructions to the corresponding monitoring nodes through the gateway nodes; the access terminals are in communication connection with the service platform, and used for accessing the service platform and controlling the corresponding gateway nodes and/or the monitoring nodes through the service platform. Compared with the prior art, the intelligent monitoring system provided by the invention can be applicable to various application environments, saves a large number of cables, and is convenient in system layout, simple in networking, and reliable in data transmitting; the reusability of the system is enhanced; the maintenance cost is reduced; the popularization and application of the technology are facilitated.

A method and an apparatus are provided to remote boot a diskless computer on a WAN and the are disclosed. The remote boot apparatus is constructed as an embedded interface in the computer. The remote boot apparatus has a bi-directional buffer, a central processor, a network interface, a boot ROM and an interface core routine. The remote boot apparatus intercepts normal disk read of an MBR issued by a system BIOS of a personal computer, and then redirects the disk instruction in a form of TCP/IP packet to a boot server to read a corresponded file block from a location of the server. After the file block is received and confirmed by the computer, the received file block is unpacked and supplied to boot the computer.

A transport layer control device includes a controller to establish or release a transmission control protocol (TCP) connection and to process retransmission of a lost packet using TCP, and a packet processor to number packets and to process transmission of the numbered packets using a user datagram protocol (UDP). A method for transmitting a packet includes establishing the TCP connection with a receiving device, numbering packets and transmitting the numbered packets to the receiving device using UDP, and retransmitting a lost packet to the receiving device using TCP in response to a retransmission request for the lost packet. A method for receiving a plurality of packets includes establishing the TCP connection, receiving numbered packets using UDP, requesting retransmission of a lost packet using TCP, and receiving the lost packet through TCP.

Devices, systems and methods for providing a ring topology for physically connecting compute devices having PCIe bridges are disclosed. Each device, having an internal PCIe bus or other similar standard that natively support a tree structure, is connected in a ring to neighboring compute devices. Two physical links connecting each device to the ring are provided, enabling each device to communicate with all of the other devices on the ring, without requiring a server or main host to enumerate or control the flow of information between devices. If a failure occurs in the physical connection at any single point in the ring, there is still an alternate path to communicate with every device. Methods for performing data transfer between PCIe compute devices connected to the ring are also disclosed.

In a hearing aid system comprising two hearing aids between which wireless signal transmission is provided. The hearing aids are automatically switched on and off. To this end, a field strength or value of an electromagnetic signal received by a hearing aid that is transmitted from the respective other hearing aid may be determined. The determined value is compared with a threshold value, the relevant hearing aid being switched off (sleep mode), as long as the field strength is greater than the threshold value and the hearing aid being switched on as long as the measured field strength is lower than the threshold value.

The invention provides a multipath TCP (transmission control protocol) congestion control method based on continuous message marks. The multipath TCP congestion control method based on the continuous message marks comprises the following steps of adding congestion marks on outputted messages by using an exchanger when a buffer queue length is greater than a mark threshold value K; confirming message feedback congestion marks by using a receiver server; receiving confirmed messages and confirming a message matrix MTi by using a transmitter server according to mark updating; calculating the sum of variable quantities of the matrix in a time bucket T; calculating a congestion factor alpha if the sum of the variable quantities of the matrix in the time bucket T is greater than a congestion threshold value theta; proportionally reducing congestion windows according to the alpha under the condition that the alpha is smaller than or equal to 1/2; transmitting mark locations of congestion window reduction of the messages; and increasing the congestion windows according to a coupled growing algorithm if the value in the specification is not greater than theta or the confirmed messages do not have congestion marks. Congestion state information of paths can be accurately fed back to a transmitter within an RTT (round-trip time), the congestion windows are reduced in a restraint manner proportionally, various links are utilized sufficiently, implementation of multipath transmission is guaranteed, and the multipath TCP congestion control method is suitable for a data center network of a multipath framework.

The invention brings forward an underground parking lot LED illumination and guiding system and method based on a self-networking technology. The system comprises LED light fixtures, a parking path planning guiding system, and LCDs installed in a parking lot and outside the parking lot for displaying parking place information of an underground parking lot, and further comprises parking place detection terminals which are provided with ultrasonic sensors and are installed in parking places, a DALI light modulation system, a center sever with double gateways, and a ZIGBEE wireless communication network composed of ZIGBEE modules. The LED light fixtures are integrated to form radar detection sensors installed at upper ends of travel paths of the parking lot; the center server employs a DALI protocol and the DALI light modulation system for communication and realizes automatic light modulation on the multiple LED light fixtures; and the center server employs a ZIGBEE wireless communication mode to communicate with the multiple parking plate detection terminals. The invention further brings forward a method based on the system.

The invention discloses an in-chip connection management-based RDMA (Remote Direct Memory Access) communication method, which comprises the following implementation steps: (1), building a context data transmitting structure and a context data receiving structure in a network interface card, building a descriptor queue, a short message receiving queue and a completion event queue in a host internal memory; (2), submitting RDMA written descriptor to the descriptor queue in the host internal memory by a source node host, and obtaining the descriptor to be processed by a source node network card; (3), checking that the current required descriptor is RDMA written descriptor by the source node network card, and building connection between the source node and an objective node network card chip; and (4), based on the connection, obtaining data from a local machine by the source node in a DMA manner, and then sending to the objective node network card. The method has the advantages of good extensibility, multi-channel transmission supporting, reliable data transmission, high multinuclear treatment efficiency, and low single-message message transmission delay.

A multi-station RF thermometer and alarm system measures temperatures and/or percent relative humidity at remote locations by RF weather stations, and displays received temperature and/or other weather data telemetry on a multi-station base station that provides out-of-bounds alarm signal indications whenever temperatures are outside of user-selectable minimum and maximum values. Randomized transmission times in one embodiment and two-phase unique transmission schedules in another lessen the possibility of on-going collisions between two or more transmitters contending for the base station at the same time. Redundant data transmission lessens the possibility of environmental noise interference. The redundant data, transmitted at random times in one embodiment, includes a unique channel ID code, house-keeping data, the current temperature and/or time-to-next-transmission data, and in another embodiment, transmitted at uniquely prescheduled times of two-phase transmission schedules, includes station location ID and transmission schedule phase. The weather parameter sensing transmitters operate at a low duty cycle with low peak current consumption resulting in long battery life. The multi-station base station may be AC- or battery-powered. Channel and station ID switches are provided on the remote temperature sensing transmitters and on the multi-station base station in one embodiment and a station ID number selection switch is provided in another transmitter embodiment.

The invention discloses a traffic intelligent management and control and service release strategy method adapting to edge computing. Organization and distribution of high-precision feature identification map data across intelligent roadside facility nodes under the beyond-visual-range linear/networked condition, multi-source spatio-temporal traffic data adaptive perception and scene intelligent identification across intelligent roadside facility nodes, cross-intelligent roadside facility node localization action domain calculation and differentiation strategy generation method are realized soas to provide adaptive traffic facility supply side service capability for intelligent traffic, especially vehicle-road cooperative application and future automatic driving application.

A method of guiding a user in an environment particularly in a building, utilizes at least one first communications unit communicating data to a mobile second communications unit carried by the user. The first communications unit transmits a contact signal within a predetermined range for establishing contact with the second communications unit. If the second communications unit is located within the range and receives the contact signal, contact is established between the first communications and the second communications unit. In order to enable guidance of the user through the environment by means of the second communications unit, data are communicated from the first communications unit to the second communications unit.

The invention provides a communication system based on a CAN (Controller Area Network). The system comprises a master station and a plurality of slave stations in a CAN network. The master and slave stations respectively consist of equipment nodes. The master station comprises a monitoring unit, a management unit, a configuration unit and a first data unit. The slave station comprises a command responding unit, a second data unit and a configuration responding unit. The invention further provides a corresponding communication method. According to the system and the method, real-time reliable data transmission can be realized in small and medium-sized industrial automatic applications, and meanwhile, the defect of difficulty in development caused by large and all inclusive regulation in existing CANopen protocol is abandoned. The system and the method are conveniently realized on small and medium size equipment.

The invention provides a method for achieving continuous broadband communication. In an improved communication scheme of a high-speed railway, firstly the network architecture is improved, a virtual single-cell topological structure is provided, a base station selects suitable radio remote units (RRUs) to serve user terminals by the aid of position information of the RRUs, when the base station selects a plurality of RRUs to serve the user terminals, the joint beamforming pre-processing is performed on signals to be sent according to channel state information between the plurality of RRUs and the user terminals.