KR20090116531A - Sensor node and ncap system structure, method for controlling a data thereof - Google Patents

Abstract

PURPOSE: A sensor node, an NCAP system structure connected to the sensor node and a data processing method using the same are provided to reduce the probability that a transmission error is generated when transmitting data in a wireless sensor network environment. CONSTITUTION: A CPU(12) controls a sensing function as a whole. A memory(14) stores TEDS(Transducer Electronic data sheet) data. An RF transmitter(16) wirelessly transmits sensing data to an NCAP(Network Capable Application Processor). The TEDS includes a basic TEDS which has a manufacture ID, a model number, a version number and a serial number and a standard template TEDS which has a template ID for showing information of a sensor node(10).

Description

Sensor node and NCP system structure connected to sensor node and data processing method using same {SENSOR NODE AND NCAP SYSTEM STRUCTURE, METHOD FOR CONTROLLING A DATA THEREOF}

The present invention relates to a sensor network, and in particular, in a sensor network-based system, a sensor node capable of expansion and efficient management of the sensor node, an NCAP system structure connected to the sensor node, and data using the same It relates to a treatment method.

With the advent of the ubiquitous era, sensor network technology, which integrates micro sensor, wireless communication, and micro microprocessor functions, is being actively researched in a wide range of applications as the foundation technology for building a ubiquitous computing infrastructure.

The sensor network is a wired or wireless network composed of a plurality of sensor nodes arranged in a specific area, for example, a distributed system of hundreds or thousands of small sensors. Each sensor node has a structure that uses a near field communication device, operates on a battery, and delivers data using ad-hoc routing. These sensor nodes should basically be provided with information acquisition through sensors, communication over wireless networks, and ultra-low power capabilities. Above all, the use of sensor nodes should be convenient.

However, since sensor nodes are very diverse and each sensor node has its own unique characteristics and different connection methods, it is necessary to identify and apply the specifications and characteristics of each sensor node in using the sensor node. Doing so can be a very cumbersome task.

Therefore, when the sensor node stores its own characteristic information and connects with other systems, it is necessary to have a method of making it compatible with each other based on the stored information. Thus, the IEEE 1451 standard was established and published.

The IEEE 1451 aims at providing flexibility and convenient maintenance of plug-and-play functions by facilitating connection between a transducer, an acquisition system, and a network. do. In addition, IEEE 1451 defines a standard interface between a network and a transducer (i.e., a sensor node or an actuator), so that a sensor or actuator supplier only needs to provide a standard interface regardless of the type of network to be connected or the connection structure. Regardless of the actuator or actuator, the standard interface makes it easy to acquire and control information.

Currently, IEEE 1451 is a draft standard from IEEE 1451.0 to IEEE 1451.6. Among them, IEEE 1451.1 defines a model of NCAP (Network capable Application Processor) to be described later, IEEE 1451.2 defines a hardware communication channel between the transducer and the NCAP by using the Transducer Independent Interface (TII), IEEE 1451.3 Defines communication protocols for each layer, IEEE 1451.4 supports plug-and-play by supporting mixed mode communication protocols and secured Transducer Electronic Data Sheet (TEDS) format, and IEEE 1451.5 supports transducer and NCAP. It defines a standard for the connection of air interfaces between devices.

Meanwhile, TEDS defined in IEEE 1451.4 is data provided to accurately use signals from sensor nodes and to distinguish types of sensor nodes. These data are stored in a memory provided in the sensor nodes, and when the sensor nodes operate, TEDS Is transmitted over the transport channel.

However, conventional sensor network-based sensor nodes and sensing data processing using such sensor nodes have the following problems.

First, the IEEE 1451.4 standard, which supports the TEDS format of sensor nodes, is a system in which sensors and information acquisition systems are wired.

Therefore, it was difficult to apply this to the wireless sensor network environment. That is, the IEEE 1451.4 standard TEDS data is over 20 bytes in size, and when the TEDS data is transmitted in a wireless sensor network environment, there is a high probability that the data is not normally transmitted. In this case, managing a large number of sensor nodes is also accompanied by difficulty.

In addition, when the sensor node is added in the conventional information acquisition system to which the sensor node is connected, the sensor node management program must be modified to receive information from the sensor node. Therefore, if a large number of sensor nodes are added to reconfigure the sensor network including the same, a lot of time and money are consumed.

Accordingly, an object of the present invention is to provide a sensor node in which a TEDS is stored together with a new structure of TEDS for application to a wireless sensor network environment.

Another object of the present invention is to provide an NCAP system structure to which sensor nodes on which a new TEDS is implemented are connected.

Still another object of the present invention is to more accurately acquire data sensed by a sensor node in an NCAP system and to effectively manage the sensor node.

According to a feature of the present invention for achieving the above object, a CPU for controlling the sensing function as a whole, a memory (TEPROM) for storing TEDS data, and for wireless transmission of the sensing data to the Network Capable Application Processor (NCAP) It is configured to include an RF transmitter, wherein the TEDS data, the manufacturer ID (Model ID), Model number (Model number), Version number (Version number), Basic number having a serial number (Serial number), and sensor node information It consists of a standard template TEDS with a template ID to represent.

The sensor node stores only the transducer electronic data sheet (TEDS) data having a size of 9 bytes, and the manufacturer ID, model number, version number, and serial number each have a 2-byte size in the TEDS data. The template ID is 1 byte in size and the basic TEDS is configured to hold 64 bits.

According to another feature of the invention, the sensor node having the above-described configuration, and the NCAP for connecting the sensor node and the network, wherein the NCAP is one or more template DB that items and values for the template of the sensor node DB The NCAP is configured to access the corresponding template DB according to the template ID included in the TEDS data, and to process the information on the sensor node by mapping the TEDS transmitted from the sensor node and the template DB.

It further comprises an operational NCAP that performs additional functions and reconfigurations for the template.

The NCAP includes an operating system based program of a sensor node, an NCAP program for signal processing and monitoring, a template DB management program, and a management program for the operating NCAP.

 The template DB stores detailed items of the sensor node, and above each template DB item, a manufacturer ID, a model number, a version number, and a serial number are necessarily expressed to obtain information of the sensor node. It is further expressed and constructed.

According to another feature of the present invention, in a sensor network configuration in which a sensor node, an NCAP having a DB communicating with the sensor node and storing an item and values for a template, and an operational NCAP are connected, the NCAP is connected to the sensor node. Receiving TEDS data, searching for a corresponding template DB in the DB by referring to a template ID included in the transmitted TEDS data, and searching for a template DB in the DB; Performing a mapping operation with a DB, the step of finding information of the sensor node according to the mapping result, processing the sensing data applied from the sensor node by the template ID and calculating the actual value.

The NCAP receives only 9 bytes of TEDS data from the sensor node.

The mapping operation may include a manufacturer ID, a model number, a version number, a serial number, and a manufacturer ID, a model number, a version number, and a serial item, which is an upper item of the corresponding template DB selected by the template ID included in the TEDS. The numbers are compared and the values stored in the matching items are read according to the comparison result.

If the template DB is not retrieved or if there is no mapping result, the NCAP determines that a sensor node has been added and requests information about a sensor node from the operating NCAP, and the NCAP requests information from the operating NCAP to the sensor node. When the information is authorized, the sensor node information is registered in the DB according to the template format.

According to the sensor node of the present invention having the above configuration and the NCAP system structure connected to the sensor node, and a data processing method using the same, the following effects are obtained.

First, by changing the format of TEDS defined in IEEE 1451.4 to ensure that only 9 bytes of TEDS data are transmitted from the sensor node to the NCAP, it is possible to reduce the probability of transmission error during data transmission in the wireless sensor network environment. It works.

In addition, since NCAP is provided with a template DB, when TEDS data is delivered from the sensor node, the corresponding template DB is accessed according to the template ID included in the TEDS data to process the sensed data. can do.

In addition, even if a sensor node is added, data processing can be performed simply by registering only sensor information in a template DB, thereby eliminating the inconvenience of a system requiring modification of a conventional program.

Hereinafter, a sensor node, an NCAP system structure connected to the sensor node, and a data processing method using the same will be described in detail with reference to a preferred embodiment shown in the accompanying drawings.

1 is a diagram illustrating an overall configuration of a sensor node and an NCAP connected according to an exemplary embodiment of the present invention.

1, a plurality of sensor nodes 10 are provided. The NCAP 20 is provided to connect the sensor node 10 with a network. In addition, an NCAP 40 is provided to control the reconfiguration and addition of a template included in the NCAP 20 and to perform a role as a DB server. The sensor node 10 and the NCAP 20 are wirelessly connected, and the NCAP 20 and the operating NCAP 40 are connected by a network.

Next, the sensor node and the NCAP configuration will be described in more detail with reference to FIG. 2.

First, the sensor node configuration.

The sensor node 10 includes a CPU 12 for controlling the sensing function as a whole, a memory (EEPROM) 14 for storing TEDS, and an RF transmitter 16 for wirelessly transmitting the sensed data. . In addition, although not shown in the drawing, an extended function unit, an analog transducer function unit, a data interface, and the like are further configured.

Hereinafter, the configuration and function of the sensor node 10 will be described in detail.

First, the OS of the sensor node 10 is implemented based on a real-time operating system such as 'Tiny-OS' for sensing function and communication between each sensor node.

In addition, the CPU 12 preferably uses a microcontroller using a reduced instruction set computer (RISC) structure such as 'Atmega128'. The Atmega128 supports 128kbyte In-System Reprogrammable (ISR) based flash memory and 4kbyte memory (EEPROM), and additionally supports external flash memory 512KBYTE and external SDRAM 32kbyte. In order to communicate between the sensor nodes, an ad-hoc network may be configured using a protocol such as 'AODV' to exchange data with each other.

In addition, the sensor node 10 has a communication frequency range of 2.4 ~ 2.4835 GHz, the RF transmitter 16 uses 'CC2420' of Chipcon (Chipcon), and has a transmission speed of 250kbps. The transmission distance is about 30m and can communicate with neighboring sensor nodes that are within the recognition distance.

Meanwhile, TDES (Transducer Electronic data sheet) data is stored in the memory 14 of the sensor node 10.

The TEDS data may be composed of 'basic TEDS', 'Standard Template TEDS', and 'user data' areas. The 'basic TEDS' includes essential confirmation information, and includes a manufacturer ID, a model number, a version number, and the like. The 'Standard Template TEDS' indicates sensor type, template ID, and 'ID number of bits' which are important information of the sensor. 'user data' is used according to user selection.

In this embodiment, in consideration of the wireless environment, 'basic TEDS' is maintained to 64 bits, but unnecessary items are deleted and reconfigured, and 'Standard Template TEDS' is configured to express only a template ID.

So, only 'basic TEDS' and template ID are stored in the sensor node.

The items and characteristics of the TEDS according to the present embodiment are shown in the following [Table 1].

TABLE 1

Item size characteristic Manufacture ID 2 bytes Manufacturer's unique number Model number 2 bytes Classification by sensor type by manufacturer Version number 2 bytes Represents the sensor version divided by type Serial number 2 bytes Express unique number of sensors according to each version Template ID 1 byte Format template

Here, the 'Model number' and the 'Serial number' may be the same when they are different 'Manufacture ID', and may have the same 'Serial number' when the 'Model number' is different in the same 'Manufacture ID'.

In addition, the sensor node 10 separately stores the 'basic TEDS' and the template ID, and the sensor node 10 transmits only 9 bytes of TEDS data. This is to reduce the probability of data transmission failure that can be increased by transmitting more than 20 bytes of IEEE 1451.4 standard TEDS in a wireless sensor network environment, and to easily manage the sensor nodes.

Meanwhile, in communication with the sensor node 10 and the NCAP 20, a template for providing information about the sensor node 10 is used. The template classifies necessary items according to the sensor node 10 or the type of actuator, and has a different format according to the template ID.

Table 2 shows the items and characteristics of Template 39 defined to represent the potential difference attributes in IEEE 1451.4.

TABLE 2

Item characteristic Sensitivity Sensor sensitivity Sens @ Ref Signal module MapMeth Calculations Used for Calibration MinPhysVal Lowest value within the actual measuring range MaxPhysVal Maximum value within actual measuring range MinElecVal Lowest value within the electrical measurement range MaxElecVal Maximum value within the electrical measurement range

The detailed items included in the template 39 apply equally to all sensor nodes using the specified template, and the values of the items appear differently according to the TEDS information.

The following describes the NCAP configuration.

The NCAP 20 connects the sensor node 10 with a network, provides computing power to process data, and generally performs a role of monitoring in a network environment.

In addition, the NCAP 20 is implemented in an object-oriented model, consisting of three blocks. The block is connected to the sensor node 10, a transducer block 22 for receiving data, converting and processing data, and a function block 24 for determining and controlling the data. ), And an NCAP block 26 that specifies an addressing scheme for connecting to the network and a place to connect.

The NCAP 20 is also provided with a database (DB) 28 in which items and values for the template are registered. The DB 28 is provided with a plurality of templates DB 29. The template DB 29 stores details related to the TEDS in the sensor node 10 through a data sheet, and the template DB 29 is formed by the number corresponding to the template ID type. Normally, template IDs have 15 types from 25 to 39, and thus 15 template DBs 29 are provided. When the template DB 29 is generated, the format of the file name may be configured as 'Template_ <ID> .mdb'. For example, the file name for Template ID 39 is Template_39.mdb.

3 is a diagram illustrating a method of accessing a corresponding template DB using the template DB configuration and the template ID. The template ID accesses the template DB by checking the manufacturer ID, model number, and version number.

4 is a diagram showing the template DB configuration.

4, in order to obtain the information of the sensor node 10, the manufacturer ID, the model number, the version number, and the serial number must be expressed above the items of each template DB 29. It can be seen that. The DB is implemented using MS-Access.

Referring back to FIG. 2, the NCAP 20 includes a program providing unit 30 that provides four system programs for developing an IEEE 1451 based system. The program providing unit 30 includes a Tiny-0S-based program operating in the sensor node 10, an NCAP program that receives, processes, and provides a signal, a DB program implemented to manage a template in the NCAP 20, and a NCAP. It is a program that manages the operating NCAP 40, which is connected to the 20 and TCP / IP and functions as a DB-server.

Meanwhile, the DB 28 may be provided to the NCAP 20 or the operating NCAP 40.

Next, the sensor node having the above-described configuration and the operation of the NCAP system for receiving and processing data from the sensor node will be described.

5 is a flowchart illustrating a data processing method in an NCAP system structure according to an embodiment of the present invention.

First, TEDS data for each sensor node 10 connected to the NCAP 20 is stored in the DB 29 of the NCAP 20. The TEDS stored in the sensor node 10 is registered in the NCAP 20 through mapping with the DB 28 registered in the NCAP 20.

In this state, when the sensor node 10 is first connected to the network (S100), when a transmission path is established by a path request message, the sensor node 10 may store 9 bytes of TEDS data stored in the memory 14 in the NCAP. Transfer to (20) (S102).

Accordingly, the NCAP 20 transmits channel allocation information to the sensor node 10 and receives an ACK signal from the sensor node 10. Accordingly, a channel for transmitting and receiving data is normally allocated between the sensor node 10 and the NCAP 20 (S104).

Once the channel assignment is made, the sensor node 10 senses the surrounding information and transmits the TEDS data along with the sensed data to the NCAP 20 through the established path and the assigned channel ( S106).

Then, the NCAP 20 accesses the corresponding template DB 29 of the DB 28 using the template ID included in the received TEDS data (S108).

When the template DB 29 is accessed as described above, the NCAP 20 performs a mapping operation on the TEDS information stored in the template DB 29 (S110). The mapping includes 'Manufactuer ID', 'Model number', 'Version number', and 'Manufactuer ID', '' of the parent DB of the template DB 29 selected by the template ID included in the TEDS of the sensor node 10. This is done by comparing the 'Model number', 'Version number', and reading the values stored in the matching items as a result of the comparison. As such, when the mapping result value exists (S112), the NCAP 20 provides the read values in a format corresponding to the template ID (S114).

This will be described as an example by applying a potential difference sensor. The potentiometer sensor is expressed in the form of template 39, which has seven sub-items as shown in [Table 2], and uses this item to find the actual value. Specifically, the specified relation is searched according to the value of 'MapMeth', and the actual value is found by substituting the value corresponding to the specified relation using 'MaxPhysVal', 'MinPhysVal', 'MaxElecVal', and 'MinElecVal'. If the value of 'MapMeth' is '0', find the actual value by using the formula of 'm * (Electrical Value) + b' referring to [Table 3]. Of course, if there is a modified and newly added relationship in addition to the above relationship can be added to the content.

Table 3

MapMeth value  formula 0 Phys Value = m * (Electrical Value) + b One Phys Value = m / [(Electrical Value) + b] 2 Phys Value = b + m / (Electrical Value) 3 (Phys Value) ^-1 = b + m / (Electrical Value) 4 Reserved

Where 'm' is the ratio of the eletrical range and the physical range, and 'b' is the 'MinPhysVal'.

On the other hand, when the mapping operation by the NCAP 20 in step 112, there may be a case where there is no result. In this case, the NCAP 20 determines that a new sensor node has been added (S116). As a result of the determination, the NCAP 20 requests the information on the new sensor node from the operating NCAP 20 (S118), and the NCAP 20 receiving the information on the added sensor registers it in the DB 29. (S120).

In other words, in the present embodiment, when sensing data is transferred from the sensor node 10 to a predetermined channel to the NCAP 20, the NCAP 20 performs a mapping process through the TEDS information allocated to the channel and then stores the data. To process and represent the actual values. In addition, when the sensor node is added, information about the sensor node can be registered in the DB 28 and used, thereby enabling the plug-and-play function for adding the sensor node.

On the other hand, when the user selects the desired channel of the sensor node 10 through the NCAP 20, the user can check the data entered so far, and can also display the continuity of the measured data by expressing the graph.

Next, various types of information are displayed when the sensor node 10, the NCAP 20, the operating NCAP 40, and the like are selected on the screen.

6 is a screen configuration diagram when the sensor node is selected. That is, it is a screen displayed when the arbitrary sensor node 10 is selected in the state which the structure of the sensor node 10, the NCAP 20, and the operation NCAP 40 is displayed on the screen.

The screen configuration shows whether a sensor node has been allocated to each channel, and when selecting a desired channel, lower items are expressed according to template ID and values thereof are expressed.

7 is a screen configuration diagram that appears when the NCAP is selected.

When the screen is displayed like this, the user can perform the monitoring and control operation. That is, as connection information of currently connected sensor nodes, a current state, a node address, and the number of hops passed to transmit data can be known. If you look at the screen, you can see that there are currently seven sensor nodes in operation. Also, for monitoring the sensed data, the data received for each channel is attached with the time received in the edit, and the sensing data of the sensor node allocated to the channel is shown in a graph when the connected channel is selected. The measurement range and unit of measure representation of the graph are determined using TEDS information.

8 is a screen configuration diagram when a sensor node is added.

The 'A' part in the screen diagram shows the allocation information for the channel, and the 'B' is the result of NCAP processing the data based on the sensor node information.

When the new sensor node is added as described above, the data processing results of the conventional information acquisition system and the NCAP 20 according to the present embodiment are shown in Tables 4 and 5 below.

TABLE 4

Data Payload 96 102 107 110 114 115 117 121 124 125 ... 25 25 25 25 25 25 25 25 25 25 ...

TABLE 5

Data Payload 26.65 ℃ 26.71 ℃ 26.76 ℃ 26.79 ℃ 26.82 ℃ 26.84 ℃ 26.86 ℃ 26.89 ℃ 26.92 ℃ 26.93 ℃ ...

Table 4 shows the results of data processing in the conventional information acquisition system. Here, it can be seen that the upper data represents the lower 8 bits, the lower data represents the upper 8 bits, and the lower and upper bits are processed in reverse order.

On the other hand, as shown in Table 5, since the data processing result in the NCAP 20 uses TEDS data, it can be seen that data sensed correctly is processed.

Although described with reference to the illustrated embodiment of the present invention as described above, this is merely exemplary, those skilled in the art to which the present invention pertains various modifications without departing from the spirit and scope of the present invention. It will be apparent that other embodiments may be modified and equivalent. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

1 is an overall configuration diagram connected to the sensor node and the NCAP according to an embodiment of the present invention.

2 is a detailed configuration diagram of the sensor node and NCAP of FIG. 1;

Figure 3 is a configuration diagram showing a method for accessing a corresponding template DB using the template DB configuration and template ID in the present invention.

Figure 4 is a template DB configuration of Figure 3;

5 is a flowchart of a data processing method in an NCAP system structure according to an embodiment of the present invention.

6 is a screen configuration diagram when the sensor node is selected.

Fig. 7 is a screen configuration diagram when the NCAP is selected.

8 is a screen configuration diagram when a sensor node is added.

* Description of the symbols for the main parts of the drawings *

10: sensor node 14: memory

20: NCAP 28: DB

29: template DB 30: program provider

40: Operational NCAP

Claims (10)

CPU to control the sensing function as a whole, Memory for storing TEDS data (EEPROM), and It is configured to include an RF transmitter for wireless transmission of the sensing data to the Network Capable Application Processor (NCAP), The TEDS data includes a basic TEDS having a manufacturer ID, a model number, a version number, a serial number, and a serial number, and a template ID for indicating information of a sensor node. Sensor node, consisting of a standard template TEDS with ID). The method of claim 1, The sensor node stores TEDS (Transducer Electronic data sheet) data having a predetermined byte size. The manufacturer ID, model number, version number, serial number, and template ID in the TEDS data have different sizes, and the basic TEDS is configured to maintain a predetermined bit. A sensor node having the configuration of claim 1, A NCAP connecting a network with the sensor node; The NCAP includes one or more template DBs in which items and values for a template of the sensor node are DBd. The NCAP system is configured to access the corresponding template DB according to the template ID included in the TEDS data, and to process the information on the sensor node by mapping the TEDS transmitted from the sensor node and the template DB. rescue. The method of claim 3, NCAP system structure, characterized in that it further comprises an operational NCAP to perform additional functions and reconfiguration to the template. The method of claim 4, wherein The NCAP system structure of the NCAP further comprises an operating system-based program of the sensor node, the NCAP program for signal processing and monitoring, the template DB management program, the management program for the operating NCAP further comprises. The method of claim 4, wherein  The template DB stores detailed items of the sensor node, and above each template DB item, a manufacturer ID, a model number, a version number, and a serial number are necessarily expressed to obtain information of the sensor node. NCAP system architecture, characterized in that it is further represented and configured. In a sensor network configuration in which a sensor node, a NCAP having a DB communicating with the sensor node and storing an item and values for a template, and an operational NCAP are connected, The NCAP receiving TEDS data from the sensor node; Searching for the corresponding template DB in the DB by referring to the template ID included in the transmitted TEDS data; If a template DB is found in the search step, performing a mapping operation between the TEDS and the template DB, and Searching for information of the sensor node according to a result of the mapping, processing the sensing data applied from the sensor node according to the template ID, and calculating an actual value. . The method of claim 7, wherein The NCAP is a data processing method in the sensor network, characterized in that only receiving the TEDS data of a predetermined byte size from the sensor node. The method of claim 7, wherein The mapping operation may include a manufacturer ID, a model number, a version number, a manufacturer ID, a model number, a version number, a serial number, a manufacturer ID, a model number, a version number, and a higher item of the corresponding template DB selected by the template ID included in the TEDS. And comparing the serial numbers and reading the values stored in the matching items according to the comparison result. The method of claim 7, wherein If the template DB is not retrieved or there is no mapping result, Determining, by the NCAP, that a sensor node has been added and requesting information about a sensor node from the operating NCAP; And the NCAP is configured to register sensor node information in a DB according to a template format when receiving information about the sensor node from the operating NCAP.

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