61 results about "VHF Data Link" patented technology

A method for validating positional data in vehicle surveillance applications wherein vehicles transmit positional data indicating their own position to surrounding vehicles using a data link over which a transmission is initiated at a given transmission point in time that is known by all users of the data link. A signal transmitted from a radio source over the data link is received at a receiving unit. The signal carries positional data indicating an alleged position of a vehicle. The distance between the receiving unit and the radio source is estimated based on the time of flight and the propagation velocity of the received signal. The time of flight is determined based on the time elapsed from the transmission point in time of the signal to the time of reception of at least a first part of the signal. A deviation value is determined. The deviation value indicates the difference between the distance to the position of a vehicle according to the received positional data and the estimated distance to the radio source.

Network interface circuitry for a secure one-way data transfer from a sender's computer (“Send Node”) to a receiver's computer (“Receive Node”) over a data link, such as an optical fiber or shielded twisted pair copper wire communication cable, comprising send-only network interface circuitry for transmitting data from the Send Node to the data link, and receive-only network interface circuitry for receiving the data from the data link and transmitting the received data to the Receive Node, wherein the send-only network interface circuitry is configured not to receive any data from the data link, and the receive-only network interface circuitry is configured not to send any data to the data link. The network interface circuitry may use various interface means such as PCI interface, USB connection, FireWire connection, or serial port connection for coupling to the Send Node and the Receive Node.

Disclosed are a terminal and method for a terminal automatically switching data link. The method comprises: after receiving a notification from a modem for setting up a first network connection, an application processor retrieves an access point name (APN) required for setting up the first network connection, and notifies the modem to switch to a second network connection when the retrieved APN is null; the modem switches to the second network after receiving a network connection change notification transmitted by the application processor, and notifies the application processor. The method and terminal of the present invention can automatically switch to a second network to set up a data link when the APN required for setting up a first network connection does not exist and data traffic cannot be used.

The invention discloses a downlink data transmission control method, a system and equipment in a time division duplex high-speed downlink packet access system, which reduce the control overhead of a base station and further improve the transmission capacity of the downlink data. The method which controls the transmission of the downlink data comprises the following steps: after initial transmission of a data packet is carried out to user equipment on a pre-appointed initial transmission code channel, confirmed feedback information after the user equipment correctly receives the data packet iswaited for being received on a initial transmission feedback channel corresponding to the pre-appointed initial transmission code channel; moreover, when the confirmed information is not received on the initial feedback channel, retransmission control information is sent to the user equipment on a control channel which is configured for the user equipment, and the data packet is retransmitted. The downlink data transmission control system comprises user equipment and a base station. The embodiment of the invention also discloses a base station and user equipment.

The embodiment of the invention discloses a link load balancing method of an SDN network and an SDN controller, and relates to the field of communication. The link load balancing method can makes fulluse of the link resources of the SDN network and can improve the network overall performance. The link load balancing method of the SDN network comprises the steps of, by the SDN controller, calculating data links which can be used by the SDN network based on link information reported by a switch, wherein the link information comprises a link capacity; adding ports which have the same target address and correspond to the data links into a load port group and configuring the weight of a corresponding port in the load port group based on the link capacity of each data link, wherein the weight of the corresponding port is the number of the ports; obtaining a first message of a data flow sent by the switch, and obtaining the head information of the first message; performing Hash operation based on the head information to obtain a load balancing factor; selecting a forwarding port based on the load balancing factor and the weight of each port in the load port group; and generating a forwarding flow table based on the forwarding port and sending the forwarding flow table to the switch.

The invention discloses a data chain networking method used for autonomous formation of an unmanned aerial vehicle, and a data chain system provides information sharing with high speed and high updaterate under the high-dynamic environment. The data chain networking method comprises the following steps: designing a network plane structure of a data chain, defining information frames of nodes, carrying out initial networking and node accession, executing single-node initial networking or multi-node initial networking, and finally receiving and transmitting data after the nodes are accessed into a network. Based on common single-channel wireless data-transmission ratio stations, the invention realizes all functions of autonomous networking and information receiving and transmitting of the data chain. The networking method can enable a plurality of nodes to be accessed into the network autonomously in the motion process and finish data receiving and data transmission; the data link has better fault-tolerant capability, and the nodes can fall out autonomously and do not influence the normal operation of the network. The invention solves the node network-accession collision under the single-channel condition, improves the multi-node network rapid-accession ability and ensures that the data link can be operated stably in a short time.

A method and system in a data communications system are disclosed for the establishment of multiple, related data links and the utilization of one of the data links for error correction of transmission errors occurring on the other data link. A first data link is established between a first computer system and a second computer system. In response to the establishment of the first data link, a second, related data link is established between the first and second computer systems. A plurality of data packets are transmitted from the first computer system to the second computer system utilizing the first data link. A determination is made whether each of the plurality of data packets is received correctly. In response to each determination that one of the plurality of data packets is not received correctly, the second computer system transmits a selective rejection packet for the one of the plurality of data packets to the first computer system utilizing the second data link.

A seamless switching-over system of data link based on Ethernet exchange comprises two layers of Ethernet exchange chip, dynamic MAC address for realizing data transmission, static MAC address for realizing real time monitor on data link in operation system and dynamic-static MAC address for carrying out fault- positioning of data link in operation system.

The invention discloses a data link equalization method, a mobile terminal and a computer readable storage medium. The data link equalization method is applied to the mobile terminal including two WiFi antennas and two data channels, and used for the data links generated by the upper application and transmitted by two data channels when two wireless hotspots are connected at the same time. The data link equalization method comprises the following steps: detecting the link delay of the two data channels by the mobile terminal; calculating the average link delay of the two data channels based onthe detected link delay and the preset smoothing algorithm; and confirming the data link equalization ratio of the two data channels according to the average link delay of two data channels, so thatthe data links newly built by the upper application can be allocated to two data channels for transmission based on the confirmed data link equalization ratio when the data links newly built by the upper application are detected. According to the invention, the data link equalization ratio is adjusted through the link delay of the two data channels, therefore, the data balance of the two data channels can be effectively guaranteed, and the network access efficiency is improved.

A ship perimeter information display device is provided. The device includes a sensor information input unit connected with a sensor equipped in a first ship and for receiving an input of a detection result of the sensor, an AIS information input unit for receiving an input of VDO information that is a VHF data link own-ship message contained in AIS information transmitted from the first ship to a second ship, a display unit for displaying a situational image illustrating a situation around the first ship, and a control unit for displaying, on the display unit, information indicating a difference between first state information of the first ship obtained based on the detection result of the sensor and second state information of the first ship obtained based on the VDO information.

Methods, systems, and devices are described for presence indication and determination in a wireless data link, such as a neighbor aware network (NAN) data link (NDL). A wireless station (STA) may identify a set of devices associated with the wireless data link and transmit a message to the set of devices including a presence request indicator. The STA may determine that a first subset of the set of devices are present in the wireless data link based on receiving a response to the message from the first subset. The STA may also determine that at least one device of the set of devices are absent from the wireless data link based on receiving a notice of absence message from the one device.

The invention discloses a data link allocation method, a mobile terminal and a computer readable storage medium. For a mobile terminal including two paths of WiFi antennae and two data channels, whentwo wireless hotspots are connected at the same time, the two data channels transmit data links generated by an upper application, the mobile terminal detects real-time transmission rates that the twodata channels transmit the data links, an average transmission rate of the two data channels is calculated based on the detected real-time transmission rates and a preset smoothing algorithm, and then a data link allocation ratio of the two data channels is determined according to the average transmission rate of the two data channels, and thus when detecting that the upper application newly establishes data links, the data links newly established by the upper application are allocated to the two data channels for transmission based on the determined data link allocation ratio, and the data link allocation ratio is adjusted through the transmission rates of the two data channels. Thereby, the data balance of the two data channels can be effectively ensured, and the network access efficiency can be improved.

The invention provides an out-of-band management system and an out-of-band management method. The out-of-band management system comprises at least one server, a system network switch, and a system out-of-band management controller. Each server comprises a network card, a server out-of-band management controller, and at least one piece of hardware needing out-of-band management, wherein the server out-of-band management controller is connected with the network card and is used for collecting the out-of-band information of the at least one piece of hardware and sending the out-of-band information to the network card, and the network card is connected with the system network switch through a data link and is used for sending the out-of-band information through the data link to the system network switch. The system network switch is connected with the system out-of-band management controller, and is used for sending the out-of-band information sent by each network card to the system out-of-band management controller. The system out-of-band management controller is used for conducting out-of-band management of the at least one server according to the out-of-band information. According to the scheme, the production cost of the out-of-band management system is lowered.

The invention relates to a helicopter radar data link integrated radio frequency design method. A data link, a radar common antenna and a radio frequency front end can build a directional data transmission link between a helicopter platform and a ground control station, and the directional data transmission link is used for SAR image transmission, information interaction, path planning, and instruction guidance.

The invention discloses a method for processing false connection in radio transmission and a system thereof. The method comprises the following steps: one or both sides to a data link set a transmission time interval of a heartbeat packet, embed the time interval in the heartbeat packet, and send a series of heartbeat packets to the other side according to the time interval; if the other side to the data link receives the heartbeats at the time interval, then the link is smooth, or a false connection happens, and Socket is cut off. The method and the system can effectively detect the connection state of TCP / IP links, and eliminate the false connection in time.

The invention provides a bus passenger flow detection method based on bus GPS and mobile phone signaling data, which comprises the following steps: 1) bus shift GPS data are acquired; 2) based on thebus GPS data, a continuous space-time lattice is generated; 3) based on the space-time lattice, a signaling sequence located in the space-time lattice is extracted; 4) by using the signaling sequence,a bus following user signaling data link is generated; 5) by adopting the signaling data link, on and off stops of each user are calculated; 6) non-walking candidate signaling data links with over short bus following are eliminated; and 7) the data of each shift obtained according to steps 2) to 6) are counted to calculate bus OD data. The bus travel OD is calculated from a data source obtained in the invention, investment in special equipment for passenger flow detection is reduced, and the bus travel OD calculation accuracy is higher than other methods.

The invention discloses a method for testing and evaluating LPI performance of a data link. By adopting the method disclosed by the invention, the strength of radio signals that are transmitted externally can be reduced, the radiation characteristics can be optimized, and the anti-interception capability of test equipment can be improved. The method is implemented through the following technical schemes: in a microwave anechoic chamber environment, a data link antenna 1 and a data link antenna 2 complete a data link communication function, and a microwave antenna completes the detection of a communication signal of the data link antenna 1, and simultaneously eliminates an interference signal of the data link antenna 2; a scenario driving system of an industrial control computer sets a value that meets a power control range and stepping requirements of the data link, and automatically simulates discrete track points and continuous track segments; and an analysis and evaluation system ofthe industrial control computer equivalently converts a communication distance and an interception distance obtained under existing site sizes and test conditions to a real aerial test flight scene,obtains a power control range and a stepping value of the data link, and calculates a communication LPI quality factor of the data link.

A surveillance transceiver system is provided for receiving extended squitters from Mode S transponders, translating the squitters into ADS-B state vectors in UAT format, and transmitting the ADS-B state vectors using a Universal Access Transceiver (UAT) datalink. The surveillance transceiver system bridges the gap created by differently-equipped aircraft by using multiple datalinks to provide seamless ADS-B surveillance. The module for processing the extender squitters includes a 1090 MHz receiver and a computer processor in communication with the UAT processor for parsing the squitter and composing the ADS-B state vector in UAT format for broadcast.

The invention provides a link retransmission method in wireless sensor network, the method adopts the contingent probability model to obtain the attribute of the data link of the wireless sensor network on the time and space, when the sending node continuously sends the data package for failure, forecasting the retransmission successful probability, selecting one continuous retransmission stop point and stopping retransmitting the data package to the link, the link quality of which is lower than the link quality measurable indicator, selecting the link with highest retransmission successful probability and transmitting the data. Concretely, the link retransmission method comprises the following steps: 1, building the link sudden model; step 2, building the link related model; step 3, sending the node data package retransmission decision algorithm. The data package can be retransmitted successfully and the data package lost probability is reduced.

The invention provides a VOIP (Voice over Internet Protocol) gateway voice link backup method and system. The VOIP gateway voice link backup method comprises the following step: if necessary, performing link switch. The link switch comprises the following steps: judging whether on-line communication exists or not; if the on-line communication exists, saving the scene of the on-line communication, recording the related uri and roles in the on-line communication, switching to the port of a backup uplink, taking the port of the backup uplink as an uplink port, and building a new media data channel; judging whether a calling party exists in the saved scene; if the calling party exists, obtaining the recoded uri information to start an SIP (Session Initiation Protocol) link call, and interacting with an SIP server; if a called party exists in the saved scene, waiting for receiving calling request information, and interacting with the SIP server; associating the built new media data channel with an original communication terminal. According to the VOIP gateway voice link backup method and system, a data link is recovered by switching the original uplink port; the new SIP link and the media data channel are built by recovering voices; the media data channel is associated with the data channel of the original conversation terminal. Therefore, the original communication terminal can be used for receiving and sending media data through the new media data channel, and the purpose of backing up the VIOP gateway uplink and the link switch function are achieved.

The invention provides a soil moisture status monitoring method and system, and belongs to the technical field of agricultural information. The system comprises an infrared camera system, a GPS module, a photographing controller, a data storage system, a data analysis device and an unmanned plane flight device, wherein the photographing controller, the infrared camera system and the GPS module are installed on the unmanned plane flight device. The photographing controller is connected with the infrared camera system and the GPS module through a data link. The photographing controller is connected with a ground control device and the data storage device. The data storage device is connected with the data analysis device. The method and system can formulate a scientific irrigation scheme and provide a scientific basis.

The invention relates to an apparatus (1) enabled to provide power to a powered device (2) via a wired data link (3). The apparatus (1) is configured to provide the power to the powered device (2) in accordance with a configuration determined based on at least one parameter transmitted by the powered device (2) via the wired data link (3) in a power cycle. Further, the apparatus (1) comprises a memory (12) for storing an information about the configuration and a controller (10) for controlling the apparatus (1) on the basis of the stored information to provide power in accordance with the same configuration to the powered device (12) in a subsequent power cycle after a power outage. Moreover, the invention relates to a method for operating the apparatus (1).

The invention embodiment relates to a detection method and a detection device of a data link. The method comprises the following steps: detecting the data flow of a general packet radio service (GPRS) interface; sending a data message to a GPRS server after confirming that the data flow is not changed; and reestablishing GPRS data connection if not receiving an answering response sent by the GPRS server within a preset time. The invention detects and maintains the GPRS data link by combining a data flow detection method and a heartbeat detection method so as to reduce an invalid data flow and network blockage at terminals and improve the detection efficiency.

The invention discloses a combined wireless data transmission method and a system thereof, and relates to a data transmission technology. The combined wireless data transmission method comprises the following steps of: firstly, transmitting a data link associated with data to be transmitted to a data input intelligent tool in a first wireless transmission mode; and then, opening the data link and acquiring the data to be transmitted in a second wireless transmission mode. The combined wireless data transmission system comprises a data output intelligent tool and the data input intelligent tool, wherein the data output intelligent tool transmits data information including the data link associated with the data to be transmitted to the data input intelligent tool in the first wireless transmission mode; and the data input intelligent tool opens the data link and acquires the data to be transmitted in the second wireless transmission mode after receiving the data link. By organically combining the two or more data transmission modes, the advantages of the modes are brought into play and the defects are eliminated.

[PROBLEMS] To enable automatic setting of corresponding relations between data links and bundled links thereof. [MEANS FOR SOLVING PROBLEMS] A temporary bundled link forming device (13) associates data links having the same port attributes within own communication apparatus with the identical temporary bundle link ID. A data link neighbor discovery device (11) obtains the neighboring node IDs of the data links. A bundled link forming device (14) automatically sets, as a bundled link, the data links having the same neighboring node IDs obtained by the data link neighbor discovery device (11), among the data links that are associated with the same temporary bundled link ID by the temporary bundled link forming device (13).

The invention discloses a portable multifunctional outfield inspection instrument based on a 1090ES (1090MHz Extended Squitter) data link. The inspection instrument comprises a power module as well as a display control panel, a signal processing board and a transceiving module which are respectively connected with the power module; the transceiving module is connected with an omni-directional antenna; and the signal processing board is separately connected with the display control panel and the transceiving module. The inspection instrument integrates the functions of conventional mode and S mode answering function inspection and S mode address loading of an S mode onboard responder; the inspection instrument is small, light and convenient to carry by adopting the design principles of modularization, generalization and combination, and is compact in operation and friendly in human-machine interface by adopting an alternating or direct current power supply mode and a battery power supply mode, so the instrument serves as a comprehensive outfield guarantee device of a 1090ES data link system, the detection of a host is more perfect and effective, then the problem of daily maintenance of the 1090ES data link system in the external field is solved, and the inspection instrument has wide market promotion prospect.

The method and system for data link to exit service are in use for solving that low dynamic management efficiency, waste resources, poor compatibility, and possible to influence service load-born by data link etc existed in current technique. The method includes steps: local terminal sends message of link blocked off to opposite terminal; when determining that blocking off data link is tolerable, the opposite terminal blocks off data link and returns message of confirming link blocked off to local end; after receiving the said confirming message, the local terminal blocks off data link. The invention also discloses the system composed of local and opposite terminals for exiting data link. The invention makes operational manager possible to carry out testing, replacing, and updating operations for operational links so as not to damage services. Thus, it is feasible to exit or get back services for one or more data links at one time in high efficiency, and resources saved.