Sensor network system

#The present invention relates to a system for managing locations where IC chips with a built-in sensor are installed. More particularly, it relates to a sensor location management system suitable for an application in which IC chips are installed over a wide area and measurements obtained using built-in sensors are collected from the whole area.

#Technology called MEMS (Micro Electro Mechanical System), which realizes functions of an electronic device on a micro IC chip, has been progressing remarkably in recent years. MEMS makes it possible to realize sensor chips having measurement and wireless communication functions. Measurements produced by such sensor chips can be collected by wireless communication. Such sensor chips can, therefore, be installed arbitrarily in diversified locations. They are expected to find applications where equipment management or environmental management is required to be more meticulous than before.

#When using such small wireless sensors, it becomes necessary to have a means for knowing where they are installed. To grasp where sensor chips are installed, it used to be necessary to note down locations where sensors are installed on a drawing on paper while identifying types of sensor chips installed by sensor installation personnel and subsequently register information grasped in such a way in a geographical information system (GIS). Even under such a circumstance, sensor installation personnel may be able to access the GIS via a network, but it is still necessary to associate, at where the sensor chips are installed, sensor information with location information. Such work is quite troublesome when the number of sensor chips involved is very large.

#FIG. 1 is a diagram showing an overall configuration of a microtremor measurement system according to an embodiment of the present invention.

#FIG. 2 is a diagram showing an overall view of an example of a sensor chip put in a stake-shaped container.

#FIG. 3 is a diagram showing an example of an internal data configuration of a sensor DB.

#An embodiment in which the present invention is applied to a microtremor measurement system will be described in the following with reference to the accompanying drawings. By measuring microtremor on the ground surface using an acceleration sensor or a speed sensor, the amplification characteristic of earthquake motion at the location of the measurement can be evaluated. An amplification characteristic of earthquake motion is an important parameter for evaluating local geological vulnerability. The present embodiment makes it possible to evaluate geological vulnerability not only at a representative point of a region but at locations all over the region.

#FIG. 1 shows an overall configuration of the system. A value measured by a sensor 112 included in a sensor chip 110 is received by a receiver 118 via wireless communication. The measured value is communicated to a sensor information management unit 123 and stored in a sensor DB 126. An ID 111 is attached to the sensor chip 110. The ID 111 may be, for example, a bar code, a two-dimensional code, or a small RFID tag. In the present embodiment being described below, the ID 111 is a two-dimensional code.

#In the sensor chip 110, the value measured by the sensor 112 is processed in an LSI (Large Scale Integrated Circuit) 113 and then transmitted to the receiver 118 via an antenna 114. Although the sensor chip 110 is supposed to be attached to equipment using a sticker, it may be built into a stake 201 beforehand and the stake 201 may be put into the ground to make measurement. In the receiver 118, a sensor information receiving unit 119 receives the measured value transmitted from the antenna 114, and a sensor information communication unit 120 connects the measured value to a network 122. The sensor information communication unit 120 may be provided with a wireless communication function so that it may connect to the network 122 via a wireless base station 121. The receiver 118 may be attached to a utility pole for a wired connection to the network 122. Or, it may be mounted on a vehicle so that a user may collect microtremor measurements cruising through locations and make wireless connection to the network 122.