摘要:
The present invention relates to a low power consumption networking method of an 802.15.4e wireless device that takes power used on a 4-20 mA loop, which comprises the following steps: a wireless device taking power in a loop; constructing a wireless network that is oriented to an ultra-low power consumption application; the wireless device implementing unidirectional time synchronization based on the preceding wireless network; on a basis of preceding time synchronization, completing neighbor discovery; the wireless device interacting with the wireless network; and pausing a preceding procedure according to a power monitoring result of an energy storage monitoring module. The present invention detects messages through continuously switching channels to implement quick and energy-saving unidirectional time synchronization, replaces traditional listening on beacon frames with listening on common messages on a basis of time synchronization, improves a listening sequence for neighbor discovery, enables listening only at a time slot where the beacon frames may appear and sleeps at other time, not only saving channel search time, but also reducing energy consumption that is generated in neighbor discovery, and thus reducing time and energy consumption of entire network establishment.
摘要:
The present invention provides an AP handover method based on double wireless network interface cards. A mobile terminal actively scans the signal strength of an AP, compares the scanned signal strength with the signal strength of a currently accessed AP, and if the signal strength is greater than the signal strength of the current AP, starts handover; otherwise, continuously scans till the handover succeeds. To reduce the handover delay and in accordance with the characteristic that the moving paths are basically fixed in industrial application scenarios, the present invention provides a pre-learning mechanism, that is, before formal application, information such as the location of the AP and the handover sequence in the application scenario is learned and stored in a terminal node, so that specific scanning and handover can be implemented in formal application. The present invention solves the problem of rapid AP handover in the industrial mobile network scenario, the double wireless network interface cards are used to achieve handover without interruption, and the pre-learning mechanism is used in specific industrial application scenarios, so the scanning delay is further reduced.
摘要:
The present invention relates to the technical field of terminal devices of the Internet of Things, more specifically to a semantic method for terminal devices of the Internet of Things capable of analyzing the application characteristics of terminal devices of the Internet of Things, setting down the rules for building ontology base; analyzing and building initial ontology base by using the ontology base building tool; pre-processing information from network and sensors; collecting information uploaded by sensors, updating the initial ontology base, and expanding the ontology base by collecting information searched by network. The method establishes program plan by object-oriented mode, analyzes implementing results by using existing test data or simulated data, and realizes domain updating and expansion of sensor ontology according to specific applications. The whole development and evolution of sensor ontology is increasing gradually in a spiral form.
摘要:
The present invention discloses a method and system for realizing Open vSwitch that supports 802.1p. The method comprises: a priority mode configuration stage: the switch receiving a priority configuration statement of a user and parsing the configuration statement; a configuration storage stage: storing the parsed configuration information into a switch database; and a priority-based data forwarding stage: the switch putting a received data packet into a corresponding priority queue according to said configuration information and a flow table so as to forward the data packet. The system comprises a configuration module, a configuration information storage module and a priority-based forwarding module, wherein the data priority-based forwarding module comprises a configuration reading unit, a traffic control setting unit, a flow table storage unit, a data packet parsing unit, a flow table matching unit, a flow table executing unit, a scheduling unit, priority queues, a sending unit, etc.
摘要:
An RSSI positioning method based on frequency-hopping spread spectrum technology, comprising: calibration stage: measuring the RSSI values of a plurality of channels at fixed points, and recording and calculating the ranging parameters in an RSSI ranging model; system preparation: deploying a positioning anchor node, and realizing synchronization between a target node and the anchor node; conducting communication on the target node by respectively utilizing a plurality of channels to obtain the RSSI values; signal processing stage: processing the RSSI into signal strength amplitude and performing optimization; and positioning stage: calculating a distance and the target node position on a positioning server according to each of the signal strength. The present invention solves the problem that low RSSI positioning precision cannot satisfy the actual requirements because a traditional RSSI positioning method is limited to factors such as multipath signal transmission, co-channel interference, obstacle interference and low coordinate calculation precision of a trilateration method.
摘要:
The present invention relates to the field of architecture of Internet of Things, specifically to a semantics-based architectural model of Internet of Things. The present invention puts forward the architecture of the Internet of Things based on the study of semantic Web, sensor network, sensor Web, wherein the architecture is divided into 7 layers: physical layer, perception layer, gateway layer, data layer, semantic layer, service layer and application layer. By means of semantic processing of sensor data and building of sensor ontology, the architecture is capable of realizing automatic discovery of heterogeneous resources, enhancing the expression ability of data, achieving effective sharing, reuse, integration, and access to data, improveing interoperability of resources and accomplishing intellectualized service.