KR20050105129A - Short range wireless zigbee sensor network using moving train - Google Patents

Abstract

Wireless sensor network that uses railroad cars to grasp the operating status of various equipment and terminals in railway sections.

Description

Short Range Wireless ZigBee Sensor Network using Moving Train}

The existing railroad sensor network consists of a wired network using RS232C or TCP / IP wired directly connected to the sensor. Through this sensor, it checks each line for abnormalities and stops the operation when it checks for errors. Doing. Because it is a sensor for checking the abnormality of the necessary line, it was inevitable to install and use even if it costs a lot.

The railway (including subway) network consists of a fusion network of various sensors and equipment. To monitor this, errors in equipment and equipment are monitored through a sensor network with high installation and maintenance costs.

However, it is difficult to check and repair the damaged documents, and it is difficult to distinguish whether the sensor is broken or the equipment is broken. Coping with primitive ways to explore the region.

By managing parallel or independent wireless sensor network, the maintenance of railway network that wastes high cost and manpower is rationally managed and the backup function due to sensor failure or malfunction is implemented to operate fault tolerant system of railway network, which is mission critical transportation network. Is in the implementation of.

The sensor is placed on the equipment to be measured and the wireless adapter (ZigBee Client, etc.) is connected and installed on the sensor, and the wireless host (ZigBee Host, etc.) is installed in the passenger car. It is a system to monitor the state of the monitoring unit to be detected by the sensor.

Provides maximum monitoring and information in environments with no or limited network. The basic configuration of this system is shown in FIG.

As shown in FIG. 1, a mobile train (FIG. 1-40) and a backbone (FIG. 1-50) are wirelessly connected and usually use a standard WiFi network. The installed sensor nodes (Figs. 1-20 and 1-21) operate with their own batteries, and when the moving train (Figs. 1-40) enters a radius, the state of the sensor is indicated by the ZigBee Client (Figs. 1-20-1 and 1). -21-1) to the ZigBee Host (FIG. 1-30-1) and the AP in the mobile train sends sensor values to the AP of the backbone (FIG. 1-10) when the wireless network is connected. 1-11) is sent to the control server. However, a Sensor Node (FIG. 1) capable of directly connecting to a ZigBee Host (FIGS. 1-10-1 and 1-11-1) installed in an AP (FIGS. 1-10 and 1-11) of a backbone (FIGS. 1-50). -20, Figs. 1-21), and the like are shown in FIG. 1-10-1, Figs. 1-10-1, and Fig. 1-11-1, directly connected to the Backbone (Figs. 1-50) without the need to transmit data through a moving train. It will send status. That is, the transmission of the sensor status is transmitted through the ZigBee Host (Fig. 1-30-1) of the moving train (Fig. 1-40) or Backbone (Fig. 1- 1) depending on whether the connection of the backbone (Fig. 1-50) is possible or not. 50) all of the structures transmitted through the ZigBee Host (FIGS. 1-10-1 and 1-11-1) connected to each other are possible, which can be operated in a complementary form.

Each sensor node is shown in FIG. 2 and is composed of a ZigBee client (FIGS. 2-20-1) and a sensor (FIGS. 2-20). The sensor type accepts both digital and analog types, and the analog type receives signal after AD conversion after adjusting the signal level. After receiving the analog or digital signal, the ZigBee Client (Figs. 2-20-1) transmits the current state change through the RF antenna (Fig. 2-60).

Receipt of the status transmission from the sensor node is transmitted through the WLAN network after being connected to the AP connected to the WLAN network or to the system for processing of other flowers. The receiver is configured as shown in FIG. 3 and is composed of a ZigBee Host (FIG. 3-10-1) and an AP (FIG. 3-10), and additionally, a PC or similar equipment for separate processing may be connected.

An example of a connection via a mobile train is described in FIG. 4. That is, the ZigBee Host and the AP (Fig. 4-30) located in the moving train (Fig. 4-40) transmit the sensor state transmitted from the sensor node (Fig. 4-21) and establish a link (Fig. 4-70) between the two terminals. , The AP (FIG. 4-30) receives the data transmitted from the sensor node (FIG. 4-21) to the AP (FIG. 4-11) directly connected to the backbone (FIG. 4-50). 4 through 71). At this time, the link between the moving train and the backbone (Fig. 4-71) can be time-delayed even when the link with the sensor node (Fig. 4-21) is not connected at the same time when the link (Fig. 4-70) is connected. In this case, the state of the sensor node (Fig. 4-21) is stored, and the delay is transmitted when the link (Fig. 4-71) is completed. Although the configuration of FIG. 4 cannot confirm the state of the real-time sensor, it can be said that it is an inexpensive and simple configuration that can check sensor data of a wide area by the operation of a moving train.

FIG. 5 illustrates a case in which a sensor node (FIGS. 5-20) can be directly connected to a network of a backbone (FIGS. 5-50). When the sensor node (Figs. 5-20) transmits to the link (Fig. 5-70) with the ZigBee Host (Fig. 5-10) connected to the backbone (Fig. 5-50), the AP transmits this sensor data to the control center. In this case, it is possible to check the sensor value without the participation of a moving train, and it is possible to check in real time when an event of a sensor change occurs.

If you use the sensor network, you can use a variety of wireless sensor network. For example, it is possible to route to the ZigBee sensor network itself, and if you are far from the area of the wireless WiFi network, the remote sensor data is transferred to the ZigBee sensor network itself. Can be sent via Nodes. FIG. 6 is a description of such a case, in which sensor nodes are installed in a matrix structure, and sensor nodes outside the ZigBee host propagation radius connected to the AP (FIG. 6-10) when transmitting necessary information are located in the middle of the sensor nodes (FIG. 6). 6-81, FIG. 6-82, and FIG. 6-83) may transmit the state of the remote sensor node (FIG. 6-80) to the control center.

FIG. 7 illustrates an example in which a routing is performed when an intermediate routing node located in a matrix of a sensor node is disabled, and newly avoids a failed node (FIGS. 7-82) (FIGS. 7-84, 7-85, and 7-). 86, Figures 7-83).

As described above, the present invention can receive the data through the ZigBee channel using a train moving the cost of the network construction and transmit the data to the control server in the wireless data section, so that the sensor network can be constructed at a low cost. It is also configured to utilize and utilize the avoidance network for the failure of some terminals in the operation of. Therefore, the effect of enabling the management of the information of the various devices in the section required by the operator and the railroad or road in the section of the moving object including the train by simple installation.

1 is a block diagram of the entire sensor network

2 is a sensor node configuration diagram

3 is a sensor host and an AP (or bridge)

4 is a sensor data transmission through the train

5 is sensor data transmission through a fixed AP (or bridge)

6 is a data transmission diagram in a sensor network

7 is a diagram illustrating a data transmission path when an operation failure occurs in a sensor network.

<Description of the symbols for the main parts of the drawings>

10: Wireless AP, 10-1: ZigBee Host, 20: Sensors, 20-1: ZigBee Client,

30: AP in train, 30-1: ZigBee Host in train, 40: mobile train, 50: network

60: RF antenna, 70: connected wireless network connection,

80: ZigBee Node (sensor + ZigBee Client)

Claims (2)

Sensor network for transmitting and checking the state of the wireless sensor nodes using the transmission time delay method using the mobility of the mobile train. How to check the status of sensor node without additional equipment using Simple Network Management Protocol (SNMP) function of AP.