KR20070094325A - System of radio frequency identification and cummunication method of radio frequency identification - Google Patents

Abstract

An RFID system and an RFID communication method are provided to share and expand intelligently network information by analyzing group conditions and position information of a group to which a communication device belongs. A tag antenna(121) receives reader information or transmits tag information through an RFID(Radio Frequency IDentification) network by using a dipole antenna. A power unit(123) supplies power to a receiver demodulator(122), a tag controller(125), a tag memory(126), and a transmitter demodulator(124). The receiver demodulator demodulates the reader information into a digital data and delivers the result for the tag controller. The tag controller analyzes a code of the demodulated reader information and performs a data process on the code. The tag controller controls wireless communication between the RFID reader and the RFID system.

Description

RFID system and RFID communication method {System of Radio Frequency IDentification and cummunication method of Radio Frequency IDentification}

1 is a diagram illustrating a form in which an RFID system according to an embodiment of the present invention forms an RFID network.

2 is a block diagram schematically illustrating components of an RFID tag according to an embodiment of the present invention.

3 is a block diagram schematically illustrating components of an RFID reader according to an embodiment of the present invention.

4 is a data block diagram schematically illustrating the structure of a network transmission protocol used in an RFID system according to an embodiment of the present invention.

5 is a flowchart illustrating a method for establishing a network in an RFID system according to an embodiment of the present invention.

6 is a flowchart illustrating a method of exchanging data after an RFID system establishes a network according to an embodiment of the present invention.

<Explanation of symbols for main parts of drawing>

100: RFID system according to the invention 120: RFID tag

121: tag antenna 122: receiving demodulator

123: power supply unit 124: transmission modulator

125: tag control unit 126: tag memory

140: RFID reader 141: reader antenna

142: demodulator 143: RF transmitter and receiver

144: modulation unit 145: reader control unit

146: reader memory a, b: device identification information, group information

c, d: distance information, activation time information e, f: protocol information, header information

g, h: error correction information, sender address information i, j: destination address information, data

The present invention relates to an RFID system.

Currently, ubiquitous network technology has attracted the attention of many people, ubiquitous network technology means a technology that allows to naturally connect to various networks regardless of time and place.

As the next generation technology of the ubiquitous network technology, RFID technology may be cited. Among them, RFID technology introduced in commerce is representative.

In general, a commercial RFID system consists of an RFID tag attached to a product and embedded with details, an RFID reader that reads information of the RFID tag using RF communication, and the RFID tag attached to the product is located at which the RFID reader is located. Since information is transmitted through RF communication through the region, it provides a foundation for efficiently managing logistics / distribution such as distribution, assembly, price change, and sales of goods.

Such RFID communication includes 134 KHz low frequency (LF) RFID, 13.56 MHz high frequency (HF) RFID, 400 MHz to 915 MHz UHF (Ultra HF) RFID, and 2.45 GHz high frequency RFID. It is classified into telematics RFID in the 5.8 GHz band, and has a communication distance of 1m to several tens of meters for contact control and close proximity control, but it is recognized as an obstacle in using RFID communication technology in a wider area. It is becoming.

That is, like other communication technologies, it is required to develop an RFID technology capable of constructing a flexible network, extending a recognition distance, or communicating with a large number of systems in a larger area. It is a lot.

In particular, in the passive RFID system, since the recognition distance is shorter than the active and uses only a limited frequency band (for example, the passive RFID tag is available only in the 433 MHz frequency band), it is necessary to construct a network in order to more stably perform long distance communication. It can be considered impossible.

In addition, a conventional RFID reader is generally implemented through envelope detection using an amplitude shift keying (ASK) modulation scheme. According to the conventional design scheme, a data recognition rate is lowered due to a lower bit error rate.

In particular, since the RFID reader targets a tag that moves at a high speed, the radio wave environment is severely changed, and a change in the reception signal is greatly caused by an external environment change. In particular, the transmission power from the RFID reader is the energy to the RFID tag. It has a big impact on supply and recognition rates.

Due to the problems pointed out above, it is difficult to build a network using RFID, and there is a need for related technology development.

The present invention can build a network irrespective of the type of RFID reader and tag classified according to the frequency band used or the power supply method, and has a unique network transmission protocol, which provides a reader-to-reader, reader-to-tag, and tag Provides an RFID system that can be configured in a variety of topologies of large tags.

In addition, the present invention provides a RFID communication method for constructing a network using a unique network transmission protocol, sharing group information, and intelligently expanding the network when a reader or a tag forms a network.

The RFID system according to the present invention processes a network transmission protocol including device identification information, network group information, sender address information, and destination address information to construct a mutual network or to establish a network with an RFID tag to process remote data transmission. It includes an RFID reader.

In addition, when the RFID reader of the RFID system according to the present invention belongs to the network group and performs a function of a forwarder of data, the RFID reader transmits its own device identification information to receive device identification information of another RFID reader on a next path, A network is constructed by transmitting sender address information and destination address information.

In addition, the RFID reader of the RFID system according to the present invention includes distance information with another RFID reader or an RFID tag on a next path, operation activation time information, protocol information, header information, and the like as the number of target devices to communicate with is set. One or more pieces of error correction information are processed on the network transport protocol.

RFID communication method according to the present invention comprises the steps of transmitting the device identification information and registration command information from the first RFID reader or the first RFID tag to the second RFID reader or the second RFID tag; Registering, by the second RFID reader or the second RFID tag, device identification information of the first RFID reader or the first RFID tag in its network group, and transmitting its device identification information and registration command information; And registering the device identification information of the second RFID reader or the second RFID tag in the network group of the first RFID reader or the first RFID tag.

In addition, in the RFID communication method according to the present invention, the first RFID reader, the second RFID reader, the first RFID tag or the second RFID tag exchanges the network group information collected by itself with the device identification information. Steps.

Hereinafter, an RFID system and an RFID communication method according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 exemplarily illustrates a form in which an RFID system 100 according to an embodiment of the present invention forms an RFID network.

1, the RFID system 100 according to an embodiment of the present invention comprises a plurality of RFID reader 140 and RFID tag 120, RFID reader 140 according to the present invention is an RFID tag ( 120, as well as communication between the RFID reader 140 may be performed, and a network of various sizes may be constructed by forming a group.

Accordingly, the RFID system 100 according to the embodiment of the present invention includes a variety of large and small networks, and the RFID reader 140 or the RFID tag 120 forming the network processes the network transmission protocol only in the present invention. .

In addition, since communication between RFID tags, that is, communication between active tags is possible only in the case of the 433 MHz frequency band, in describing the embodiment of the present invention, the RFID reader 140 and the RFID reader 140 are described. ) And communication between the RFID reader 140 and the RFID tag 120.

First, the configuration and operation of the RFID tag 120 and the RFID reader 140 constituting the RFID system 100 according to an embodiment of the present invention will be described.

2 is a block diagram schematically illustrating components of an RFID tag 120 according to an embodiment of the present invention.

The RFID tag 120 includes a tag antenna 121, a reception demodulation unit 122, a power supply unit 123, a transmission modulator 124, a tag control unit 125, and a tag memory 126.

The tag antenna 121 receives a reader information or transmits signal information processed tag information through an RFID network, usually a dipole antenna is used.

The power supply unit 123 is a device for supplying power to the reception demodulation unit 122, the tag control unit 125, the tag memory 126 and the transmission modulator 124.

The RFID tag is classified into an active method and a passive method according to the driving method of the tag antenna 121 and the power supply unit 123. In the active method, the tag antenna 121 includes an oscillating circuit. Information is transmitted, and the power supply unit 123 is provided with a battery to provide power to the oscillation circuit. When operated in the active manner as described above, the RFID tag performs communication using a frequency band of about 433 MHz.

In addition, the passive method is a method in which the power supply unit 123 regenerates the power using the radio wave energy of the RF signal received from the RFID reader 140, the detector diode is rectified and rectified to a DC voltage using the RF signal The DC voltage is used as a power source for supplying a modulation waveform to the transmission modulator 124 by generating a response code.

The RFID tag 120 according to the present invention may be an active method or a passive method, but in the embodiment of the present invention, the RFID tag 120 is a passive tag.

The reception demodulator 122 demodulates the received reader information into digital data and transmits the demodulated reader information to the tag controller 125. The tag controller 125 analyzes the code of the demodulated reader information and processes the data (tag information). Generate).

In addition, the tag control unit 125 includes a network transmission protocol according to the present invention to control wireless communication with the RFID reader 140. The tag control unit 125 illustrates a structure of a network transmission protocol used for analyzing a code or controlling wireless communication. It will be described later in detail with reference to 4.

The tag memory 126 stores an information code system according to a network transmission protocol, and the tag control unit 125 generates tag information using the same.

The transmission modulator 124 modulates tag information into an RF signal and transmits tag identification information modulated through the tag antenna 121. In the case of the manual method, the transmission modulator 124 transmits the tag information to a backscatter method.

Next, the RFID reader 140 according to the embodiment of the present invention will be described.

3 is a block diagram schematically illustrating components of an RFID reader 140 according to an embodiment of the present invention.

Referring to FIG. 3, the RFID reader 140 includes a reader antenna 141, a demodulator 142, a radio frequency (RF) transmitter and receiver 143, a modulator 144, a reader controller 145, and a reader memory ( 146).

The reader control unit 145 includes the network transmission protocol to control wireless communication with another RFID reader 140 or RFID tag 120 and periodically to determine the location of the reader 140 or tag 120. The reader information including the information request signal is transmitted.

The reader controller 145 analyzes the code of the tag information or the reader information received from the reader 140 or the tag 120 and demodulated by the demodulator 142. At this time, the data format is converted and necessary information is extracted. Filtering is performed to

In the reader memory 146, a code analysis system according to a network transmission protocol is recorded, such as a tag memory 126, so that the reader control unit 145 uses the code analysis system and uses the analyzed tag information or reader information. The memory may be stored in the reader memory 146.

Synchronous Dynamic Random Access Memory (SDRAM) is preferably used as the reader memory 146 or the tag memory 126.

The reader antenna 141 transmits its own reader information including an information request signal through a wireless channel or receives tag information or reader information from the tag 120 or the reader 140, and the RF transmitter / receiver 143. Signal processing in the high frequency signal region by filtering or amplifying the tag information or reader information.

The modulator 144 processes the reader information of the digital signal region transmitted from the reader controller 145 into a signal of the baseband region, and the demodulator 142 receives the RF received signal transmitted from the RF transmitter / receiver 143. The signal is converted / processed into a signal of the baseband region and the digital region, and transferred to the reader controller 145.

When the modulator 144 communicates between the readers 140 or the tag 120, the double sideband-amplitude shift keying (DSB-ASK), the single sideband-amplitude shift keying (SSB-ASK), and the PR The signal may be processed using any one of a phase reversal-amplitude shift keying (ASK).

4 is a data block diagram schematically illustrating a structure of a network transmission protocol used in the RFID system 100 according to an embodiment of the present invention.

According to FIG. 4, the network transmission protocol is largely divided into 10 areas, and each area includes device identification information (a), group information (b), distance information (c), activation time information (d), and protocol information ( e), header information (f), error correction information (g), sender address information (h), destination address information (i) and data (j).

Hereinafter, in describing the network transmission protocol, the case of the RFID reader 140 will be described by way of example for convenience of description.

First, the device identification information (a) is unique identification information assigned when the reader 140 or the tag 120 is produced as a product, and may include identification information such as a MAC address.

Second, the group information (b), as described above, is information for identifying a group to which the reader 140 or the tag 120 belongs among various groups included in the RFID system 100 according to the present invention.

Third, when the distance information (c) is fixed like the reader 140, since the communication distance for each frequency band has a limit, it means information on these distances, and the readers 140 may be the most through the distance information (c). A network capable of stable data communication can be constructed.

Fourth, the activation time information (d), for example, in the case of the tag 120 has a propagation speed of about 640 kbps, one reader 140 is capable of stable communication with 200 to 300 tags 120, at the same time stable There is a limit to the time at which communication can be performed.

Therefore, the reader 140 does not always need to be in an active state, and enters the idle mode after a certain time, and the idle mode is maintained until reader information is received from the adjacent reader 140. The activation time information d denotes a time during which the reader 140 is actively operated before the idle mode.

Fifth, the protocol information (e) is information for distinguishing a network transmission protocol according to the present invention from among various protocols used for RFID communication. Sixth, the header information (f) is a code format, a version of a code system, It consists of information such as the length of the code.

Seventh, the error correction information (g) is information used for identifying and correcting an error that may occur in data communication or requesting retransmission, and may have a form such as cyclic redundancy checking (CRC) or checksum. .

Eighth, the sender address information (h) refers to the address information of the reader 140 that requests or transfers the reader information first, and the ninth, the destination address information (i) indicates that the reader information or data to be transmitted is Means the address information of the reader 140 finally delivered.

Lastly, the data j means actual data transmitted and received when a service is performed using the RFID system 100 according to the present invention after the network is established.

The stack structure of the network transport protocol is largely classified into a physical layer, a media access controller layer, a network / security layer, an application framework layer, and an application / application layer. Profiles) layer, wherein the operation of the PHY layer is performed by the demodulator 142, the RF transmitter / receiver 143, and the modulator 144.

The MAC layer, the network layer, the framework layer, and the application layer are layers processed by the reader control unit 145. When the signal processing of the PHY layer is completed, the reader control unit 145 analyzes the transmitted data frame structure. Acknowledge the frame, detect an error (detection via CRC or Checksum), determine whether to retransmit, and handle packet routing.

In addition, the reader controller 145 configures a network topology by performing functions such as a network layer and a framework layer, and transmits and receives data j by performing a function of an application layer.

Referring back to FIG. 1, the RFID system 100 according to the present invention may form three network topologies by processing the aforementioned network transmission protocol.

In FIG. 1, "R" denotes an RFID reader 140, and "T" denotes an RFID tag 120, and the network of the "A" area represents a star network. The network in the "B" area illustrates a mesh type network, and the network in the "C" area illustrates a cluster tree type network.

Hereinafter, the configuration and operation method of the RFID system 100 according to the present invention will be described with reference to FIGS. 5 and 6.

5 is a flowchart illustrating a method for establishing a network by the RFID system 100 according to an embodiment of the present invention.

Before the RFID system 100 according to the present invention describes a method for constructing a network, a network is constructed between the readers 140 (hereinafter, referred to as "first leader" and "second leader"). It is assumed that the first leader and the second leader are included in different networks from each other.

For the first time, the first leader includes his / her device identification information (hereinafter referred to as "first device identification information") and registration command information (hereinafter referred to as "first registration command information"). Transmits " first leader information " (hereinafter referred to as " first XX information " and information related to a second leader " second XX information " (S100).

In this case, the first group information, the first distance information, and the first activation time information may be included in the reader information.

Upon receiving the first leader information, the second leader confirms that the first leader is a counterpart in a stable communication area from the first distance information, and confirms a configurable network topology and node position from the first group information (S105).

The second leader includes (registers) the first device identification information in the second group information according to the first registration command information (S110).

At this time, in registering the first device identification information, the second reader records first group information, first distance information, and first activation time information together.

When the information about the first leader is registered, the second leader includes a second leader including second device identification information, second group information, second distance information, second activation time information, etc. together with second registration command information. The information is transmitted, and the first reader receives it (S115).

The first reader stores information related to the second leader in its own memory in the same manner as in the case of the second reader (S120).

In this way, when the first leader and the second leader establishes a network for the first time, the first leader and the second leader collect information of different leaders, respectively, and form a different network (S125). The reader periodically exchanges information on a new network while transmitting and receiving information related to network construction (S130).

Therefore, according to the RFID system 100 according to the present invention, long distance communication is possible through the RFID reader and the RFID tag 120 having a limited communication distance.

That is, the first leader or the second leader intelligently checks each node forming the entire network through network information exchanged with other readers periodically-collected group information, device identification information, distance information, and activation time information. It can be configured as.

6 is a flowchart exemplarily illustrating a method for exchanging data after an RFID system 100 establishes a network according to an embodiment of the present invention.

As described in FIG. 5, when predetermined networks are established and data service is performed through the established network (hereinafter, the first leader transmits data to the fourth leader via the second and third readers). For example, the first leader selects a second leader that is determined to be located closest to or activated according to the first group information (S200), and determines the waypoint address information (device identification) to the selected second leader. Information), the first transmitter side address information, the first destination address information, and the first leader information including the first data (S205).

The second reader reads the first sender side address information and the first destination address information, searches for and selects a third leader to form the next route (S210), and transmits the first leader information to the third reader (S215). ).

When the first leader information is received, the third leader determines that the first destination address information belongs to the third group information (that is, the fourth leader forms a node of the same network with itself) (S220). In operation S225, the first leader information is transmitted to the fourth leader.

The fourth reader interprets the first leader information, processes the first data, and generates fourth data corresponding to the processed first data.

When the fourth data is generated, the fourth reader generates fourth leader information including fourth device identification information, fourth group information, fourth sending side address information, fourth destination address information, and fourth data ( S230).

Subsequently, the fourth leader transmits the generated fourth leader information, and the fourth leader information is transferred to the first leader via the third leader and the second leader in the reverse manner of the above-described method (S235).

Finally, the first leader and the fourth leader information may be analyzed to obtain fourth data corresponding to the first data.

Although the present invention has been described above with reference to the embodiments, these are only examples and are not intended to limit the present invention, and those skilled in the art to which the present invention pertains may have an abnormality within the scope not departing from the essential characteristics of the present invention. It will be appreciated that various modifications and applications are not illustrated. For example, each component specifically shown in the embodiment of the present invention can be modified. And differences relating to such modifications and applications will have to be construed as being included in the scope of the invention defined in the appended claims.

According to the RFID system according to the present invention, a large number of RFID systems can build a network in a wider area, and there is an effect of performing long-distance communication stably by analyzing network groups and paths.

According to the RFID communication method according to the present invention, the entire network can be formed by configuring various network topologies, and the network information can be intelligently shared / expanded by analyzing a group, a location, an operation type, etc., to which a communicable device belongs. It works.

Claims (9)

RFID including RFID reader which handles remote data transmission by processing network transmission protocol including device identification information, network group information, sender address information, and destination address information to build a mutual network or network with RFID tag system. The method of claim 1, wherein the RFID reader is When belonging to the network group and performing the function of forwarder of data, the device identification information is transmitted by itself, the device identification information of another RFID reader on the next path is received, and the network address is transmitted by transmitting the sender address information and the destination address information. RFID system, characterized in that the building. The method of claim 1, wherein the RFID reader is RFID information processing the distance information with the other RFID reader or RFID tag on the next path on the network transmission protocol. The method of claim 1, wherein the RFID reader is And an operation activation time information on the network transmission protocol as the number of target devices to communicate with is set. The method of claim 1, wherein the RFID reader is And at least one of protocol information, header information, and error correction information on the network transmission protocol. The method of claim 1, wherein the RFID reader is When performing communication between readers or tags, any of Double SideBand-Amplitude Shift Keying (DSB-ASK), Single SideBand-Amplitude Shift Keying (SSB-ASK), and Phase Reversal-Amplitude Shift Keying (PR-ASK) RFID system, characterized in that using one modulation scheme. The method of claim 1, wherein the RIFD reader is When receiving the device identification information from another RFID reader, and transmits its own device identification information with the request information to register itself in the network group of the other RFID reader, When the device identification information of the other RFID reader is transmitted with the request information, the RFID system comprising the device identification information of the other RFID reader in its network group information. Transmitting, by the first RFID reader or the first RFID tag, the device identification information and the registration command information to the second RFID reader or the second RFID tag; Registering, by the second RFID reader or the second RFID tag, device identification information of the first RFID reader or the first RFID tag in its network group, and transmitting its device identification information and registration command information; And The first RFID reader or the first RFID tag comprises registering the device identification information of the second RFID reader or the second RFID tag in its network group. The method of claim 8, The first RFID reader, the second RFID reader, the first RFID tag or the second RFID tag comprises the step of exchanging the network group information collected by the device identification information with their own RFID communication method comprising the .

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