KR100587010B1 - Wakeup method of Zigbee transmission apparatus - Google Patents

Abstract

The present invention is to provide a wake-up method of a Zigbee terminal that can communicate without delay of data transmission and reception, and can minimize unnecessary power consumption by allowing the device to wake up only when there is data to be transmitted and received. In the wake-up method of a Zigbee terminal using an RFID system composed of an RF reader provided on the network coordinator side and an RFID tag provided on the device side, the network coordinator sets and registers a unique RFID for each device. Doing; Setting a wake-up GTS section in a Zigbee channel and notifying the corresponding devices of the set-up wake-up GTS section in a network coordinator; Checking whether the allocated wake-up GTS interval is started in the network coordinator; As a result of the check, when the set wake-up GTS period starts, transmitting a radio signal to an RFID tag of a device having data to be transmitted and received to wake up the corresponding device; And performing data transmission / reception by communicating with the network coordinator by the device waked up by the RFID radio signal.

Zigbee, Radio Frequency Indentification (RFID), Wakeup, Sleep Mode, Network Coordinator, Device, Reader, Tag

Description

Wakeup method of Zigbee UE {Wakeup method of Zigbee transmission apparatus}

1 is a configuration example of a wireless private network by the Zigbee method.

2 is a superframe structure diagram of a conventional Zigbee system.

3 is a flowchart illustrating a wake-up method in a conventional Zigbee terminal.

4 is a superframe structure diagram applied to the wake-up method of the Zigbee terminal according to the present invention.

5 is a flowchart illustrating a wake-up method of a Zigbee terminal according to the present invention.

FIG. 6 is a flowchart illustrating a processing procedure of a Zigbee terminal in more detail in the wake-up method of the Zigbee terminal shown in FIG. 5.

7 (a) to 7 (b) are block diagrams showing the configuration of a payment terminal apparatus to which the wake-up method according to the present invention can be applied.

Explanation of symbols on the main parts of the drawings

11: network coordinator

12: device

110, 210: Zigbee PHY

120: RFID reader 220: RFID: Tag

130, 230: MAC hardware engine

140, 240: memory

150, 250: MCU

160, 260: application interface

The present invention relates to a wake-up method of a Zigbee terminal capable of communicating without delay of data transmission and reception and minimizing unnecessary power consumption by allowing the device to release the power saving mode only when there is data to be transmitted and received.

ZigBee, a wireless personal area network (WPAN) technology, is a personal wireless network standard for 2.4GHz-based home automation and data featuring low power, low cost, and low speed. Standardization was underway. Referring to the above standard, Zigbee uses the frequency bands of 240 GHz, 915 MHz, and 868 MHz, and includes 250 kbps (16 channels in the 2.4 GHz ISM band) and 40 kbps / 20 kbps (10 channels in the 915 MHz band / 1 channel in the 868 MHz band). Channel) and the modem method is DSSS (Direct Secure Spread Spectrum), which transmits data at a speed of 20 ~ 250kbps within a radius of 30m, and connects up to 255 devices to one wireless network. Large scale wireless sensor network can be constructed indoors and outdoors.

ZigBee has the advantage of ultra low power consumption compared to other WPAN technologies such as Bluetooth or UWB, simplified configuration of wireless transmit / receive circuits, the lowest cost chipset, and vertical application areas such as sensor networks. Is a competitive short-range wireless communication technology.

For example, the introduction of ZigBee in lighting, fire detection, heating and cooling systems, etc., allows building managers to remotely manage and control building systems through portable devices rather than management offices.

1 shows an example of a configuration of a wireless private network according to the ZigBee technology, and is composed of a network coordinator 11 and a plurality of devices 12 connected to the network coordinator 11 to transmit and receive data.

In the above description, the network coordinator 11 is provided in a main control device of a computer or a home network. The network coordinator 11 controls the transmission and reception of data to and from the plurality of devices 12, and the plurality of devices 12 serve as input and output of actual data. For home automation, this includes heating, ventilation, air conditioning, security, lighting and sensors.

In ZigBee, in such a short-range wireless private network, ZigBee operates in superframe mode so that it can be applied to a service having a short processing delay time according to an application field. In this case, the network coordinator 11 is configured in advance. Transmit superframe beacons at time intervals. At this time, the interval of the beacon signal may be a minimum of 15ms to a maximum of 245msec.

Then, the time between the two beacons is divided into 16 identical timeslots, as shown in FIG. 2, wherein the timeslots are the access contention intervals in which the multiple devices 12 compete with each other, and the specified bandwidth or lower processing. It is divided into a contention-free period allocated to a single device requiring a delay. In this case, a time slot allocated to a predetermined device is referred to as a guaranteed time slot (GTS).

Accordingly, when the device 12 receives the beacon signal, the device 12 transmits and receives data with the network coordinator 11 during the timeslot allocated in the Zigbee channel before receiving another beacon signal, as shown in FIG. By the same procedure.

That is, when the device 12 is powered on to start operation (s31), the device 12 receives the channel discovery and the beacon frame to contact the network coordinator 11 to receive the channel information (RSSI). And the superframe structure of the network (s32). The network coordinator 11 communicates with the network coordinator 11 based on the searched superframe structure (S33).

It is determined whether there is data to be transmitted or received from the network coordinator 11 by the communication (s34), and if there is data to be transmitted or received as a result of the determination, the network coordinator 11 or another device 12 through the CSMA / CA mechanism. Transmit and receive data (s35).

When the transmission and reception of the data is completed or there is no data to be transmitted or received in the determination step (s34), after setting the time to wake up according to the beacon period of the superframe structure (s36), the operation mode is switched to the power saving mode. To reduce battery consumption (s37).

When the set wakeup time is reached (s38), the device wakes up by the self-wakeup and releases the power saving mode, and receives the beacon transmitted from the network coordinator 11 (s40). Then, the above-described data transmission / reception determination (s34) is repeated.

As described above, as a method for reducing power consumption in the related art, after confirming whether there is data to be transmitted from the network coordinator 11 according to the beacon period, and during the connection contention period (CAP) or the contention-free period (CFP) Determines whether you are awake or asleep.

Since the device 12 periodically wakes up from the power saving mode to receive a beacon frame in order to check whether data is transmitted or received, since the device 12 wakes up periodically and consumes power even when there is no data to transmit or receive, There is a problem that unnecessary power consumption occurs.

SUMMARY OF THE INVENTION The present invention has been proposed to solve the above-mentioned problems. The object of the present invention is to allow the device to release the power saving mode only when there is data to be transmitted and received, thereby enabling communication without delay in data transmission and reception, and minimizing unnecessary power consumption. It is to provide a wake-up method of the Zigbee terminal.

The present invention provides a wake-up method of a Zigbee terminal using an RFID system comprising an RF reader provided on the network coordinator side and an RFID tag provided on the device side as a construction means for achieving the above object,

Setting and registering a unique RFID for each device in the network coordinator;

Setting a wake-up GTS section in a Zigbee channel and notifying the corresponding devices of the set-up wake-up GTS section in a network coordinator;

Checking whether the allocated wake-up GTS interval is started in the network coordinator;

As a result of the check, when the set wake-up GTS period starts, transmitting a radio signal to an RFID tag of a device having data to be transmitted and received to wake up the corresponding device; And

The device wake-up by the RFID radio signal is characterized in that it comprises the step of communicating with the network coordinator to perform data transmission and reception.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description and the accompanying drawings, detailed descriptions of well-known functions and configurations related to the present invention will be omitted.

According to the present invention, in order to reduce power consumption required to periodically wake up as in the prior art, the power saving mode is canceled and operated only when there is data to be transmitted and received aperiodically using a radio frequency identification system (RFID). In other words, the minimum power consumption can be achieved.

In general, an RFID system is a system that processes information by identifying a tag of a non-contact type in a non-contact manner through a radio wave signal, an RF reader having a reading and decoding function and an RFID tag having embedded unique information. ).

The RFID tag is composed of a semiconductor transponder chip and an antenna. There are a passive method for operating by receiving energy from a radio signal from the RF reader without an internal power supply and an active method including a battery. In addition, it can be implemented as a chip tag using a silicon semiconductor chip and an LC chip, or a chipless tag composed only of a plastic / polymer device. In another form, the unique information recording method may be implemented as a read-only type and a read-write type. In the RFID tag applied to the present invention, since the RF signal should be able to be received in the power saving mode, a passive method of receiving energy from the radio wave signal of the reader is preferable, and the device is configured to wake up upon reception of the RF signal. 12), it is preferable to form read-only type.

In addition, the communication band of the RFID system is currently used in a variety of frequency bands from low frequency below 150KHz to 5GHz or more microwave, and standardization thereof is developed and operated by IEC JTC1 / SC31 / WG4 under ISO, an international standardization organization. , Is in charge of management.

Therefore, when the above RFID system is applied to the Zigbee wireless terminal, it is possible to transmit and receive a predetermined signal even in the power saving mode. The present invention applies this to the wakeup method.

The Zigbee terminal device according to the present invention includes an RFID reader on the network coordinator 11 side and an RFID tag on the device 12 side. 7 is a block diagram showing the configuration of a Zigbee terminal device according to the present invention.

Referring to FIG. 7A, the network coordinator 11 includes a Zigbee PHY (physical layer unit) 110 that transmits and receives a frequency signal of a set frequency band, and a MAC engine that controls data transmission and reception according to the Zigbee protocol. 130, a memory 140 for storing the code for Zigbee communication and ID registration information of the device, an MCU 150 for controlling the operation of the Zigbee terminal according to a predetermined control flow, an application using the Zigbee terminal, In the configuration of the Zigbee terminal device consisting of an application interface 160 for implementing the interface of the RFID reader 120 for transmitting an RFID signal so that the RFID tag of a specific ID is activated in accordance with the control signal applied from the MAC engine 130 It is further provided.

Next, referring to FIG. 7B, the device 12 includes a Zigbee PHY (physical layer unit) 210 that transmits and receives a frequency signal of a set frequency band, and a MAC engine that processes data transmission and reception according to the Zigbee protocol. 230, a memory 240 in which control data and a code of a Zigbee communication terminal are stored, an MCU 250 for controlling the overall operation of the communication terminal according to a set control procedure, and a device equipped with the Zigbee terminal device. In the configuration of the Zigbee communication terminal consisting of an application interface 260 that enables data communication with the application, it is activated by the RFID signal transmitted from the RFID reader 120, and transmits a wake-up signal to the MAC engine 230. Further provided is an RFID tag (tag) 220.

In addition, in the present invention, in order to use the RFID system, as shown in FIG. 4, a predetermined time slot belonging to the contention-free section of the Zigbee channel is allocated to the RFID channel.

Therefore, referring to FIG. 4, the superframe structure according to the present invention includes ZigBee channels including 16 time slots that divide the time between two beacon signals generated at predetermined periods by 16 equals, and the ZigBee channel includes a plurality of devices. Contention Access Period (CAP) and Contention Free Period (CFP), which are allocated to specific devices, respectively, and the contention free period (CFP), which is allocated to specific devices, is randomly allocated. A specific timeslot of the CFP is set to a wake-up GTS which is simultaneously used as the RFID channel and the Zigbee channel, and other timeslots GTS1 and GTS2 are allocated to the specific device as the Zigbee channel.

Therefore, when data to be transmitted and received occurs, the network coordinator 11 operates the RFID reader 120 provided as shown in FIG. 7A in the wake-up GTS section, thereby generating an RFID tag ( By transmitting a wireless signal to the 220 and applying the wake-up signal to the device 12, the RFID tag 220 activated by the signal is in the power saving mode state, the device 12 is released only when necessary And send and receive data.

Hereinafter, a wakeup method using an RFID system will be described with reference to FIGS. 5 and 6.

5 is a flow chart showing the basic flow of the wake-up method according to the present invention.

Referring to FIG. 5, first, unique RFIDs are set and registered with respect to a plurality of devices 12 so that each device 12 may be distinguished from the RF reader 120 (S51). The RFID list of all the devices 12 set as described above is registered in the network coordinator 11 (S51).

As shown in FIG. 4, a wake-up GTS interval is set and notified to all devices 12 present in the PAN through the network coordinator 11 (S52).

As described above, in a state where the initial setting is completed, it is checked whether the allocated wake-up GTS section has started (S53), and when the allocated wake-up GTS section starts, the device 12 having data to transmit / receive is started. The wireless signal is transmitted to the RFID tag of the device 12 to wake up the device 12 (S54).

The device 12 wakes up by the RFID signal, communicates with the network coordinator 12 according to the Zigbee protocol, and transmits and receives data (S55).

At this time, the transaction between the network coordinator 11 and the wake-up device 12 is completed within the wake-up GTS interval.

According to the above, when data transmission and reception is necessary, by activating the RFID tag 220 by the RFID signal to wake up the device 12 from the outside, the device 12 of the wireless private network in the beacon period for the transmission and reception of data You can keep the power saving mode without having to wake up. By reducing unnecessary power consumption, battery life can be further extended.

In the case of applying the method, the operation performed in each device 12 may be performed by the procedure of FIG. 6.

Referring to FIG. 6, when the power is turned on, the device 12 performs initial setting for performing an operation. As in the related art, the device 12 receives a channel search and a beacon frame in order to contact the network coordinator 11. Information (including RSSI) and the superframe structure of the network are identified (s62). In this case, the allocated wake-up GTS interval information of step S52 may be transmitted to the device 12.

Based on the searched superframe structure, the network coordinator 11 communicates with the network coordinator 11 (S62).

The subsequent operation depends on whether the device 12 can support the RFID wakeup operation.

In this case, whether to support the RFID wake-up operation for the device 12 may be determined according to whether the device 12 is provided with the RFID tag 220, and whether the RFID is assigned. Even if the distance from the network coordinator 11 to the device 12 is greater than or equal to the RFID signal arrival distance, the RFID wakeup becomes impossible. Therefore, upon initial installation, the RFID of the device 12 is transmitted to the network coordinator 11 to be registered, and in subsequent operations, the electrical strength of the signal (for example, the beacon signal) transmitted from the network coordinator 11 is determined. By detecting and calculating the reach therefrom, it can be implemented to determine whether RFID wakeup is possible (S63).

Therefore, when the RFID tag is not installed in the device 12 or the distance from the network coordinator 11 is greater than or equal to the set distance and the transmission of the RFID signal is impossible, the device 12 cannot support the RFID wakeup. If it is determined that the device operates in the self-wake mode that wakes up at a predetermined cycle as in the related art, and the RFID tag is installed in the device 12, and the distance from the network coordinator 11 is within the set distance, the device 12 Is determined to support the RFID wakeup and operates in the RFID wakeup mode.

In the self-wake mode, as in the prior art, it is determined whether there is data to be transmitted or received through communication with the network coordinator 11 (s64), and if there is data to be transmitted or received, the CSMA / CA mechanism is determined. Data is transmitted and received with the network coordinator 11 or another device 12 (s65).

When the data transmission and reception is completed or there is no data to be transmitted or received in the determination step (s64), after setting the time to wake up according to the beacon period of the superframe structure (s66), the operation mode is switched to the power saving mode. Reduce battery consumption (s67).

When the set wakeup time is reached (s68), the device wakes up by the self-wakeup and releases the power saving mode, and receives the beacon transmitted from the network coordinator 11 (s69 and s70). Then, the process is repeated again from the previous data transmission / reception determination step (s64).

On the contrary, in the RFID wakeup mode according to the present invention, the device 12 notifies the network coordinator 11 that the device 12 is switched to the RFID wakeup mode (S71). Then, the power saving mode is switched (S72).

In the power saving mode, the RFID tag 220 provided in the device 12 is activated by the radio wave of the RFID radio signal, and waits for the RF signal from the RFID reader 120 in a state where battery power is not supplied. (S73).

The state is maintained until the radio signal transmitted with its ID is received from the RFID reader 120 provided in the network coordinator 11 (S74).

When the RFID signal is received from the network coordinator 11 as the RFID tag 220 (S74), the RFID tag 220 receives power from the radio wave of the received radio signal to operate the device 12 to generate a wakeup signal. To send). Accordingly, the device 12 wakes up, releases the power saving mode (S75), and then communicates with the network coordinator 11 to transmit and receive data (S76).

In the above description of the present invention has been described with a specific embodiment, the present invention is not limited to the above embodiment, various modifications can be made within the scope of the claims below.

As described above, in the ZigBee wireless private network which has advantages of low power consumption and low cost, the present invention can use the RFID system to wake up the device only when necessary without any power consumption, and perform the operation. Result By eliminating unnecessary power dissipation in the device, it is possible to achieve ultra-low power consumption and to extend battery life even further.

Claims (6)

In the wake-up method of a Zigbee terminal using an RFID system consisting of an RF reader provided on the network coordinator side and an RFID tag provided on the device side, Setting and registering a unique RFID for each device in the network coordinator; Setting a wake-up GTS section in a Zigbee channel and notifying the corresponding devices of the set-up wake-up GTS section in a network coordinator; Checking whether the allocated wake-up GTS interval is started in the network coordinator; As a result of the check, when the set wake-up GTS period starts, transmitting a radio signal to an RFID tag of a device having data to be transmitted and received to wake up the corresponding device; And Wake-up method of the Zigbee terminal, characterized in that the device wake-up by the RFID radio signal communicates with the network coordinator to perform data transmission and reception. The method of claim 1, The wake-up method of the Zigbee terminal, characterized in that the transaction between the wake-up device and the network coordinator is completed within the wake-up GTS interval. The method of claim 1, wherein the wake-up GTS interval is A wake-up method of a Zigbee terminal, characterized in that the time interval between beacons transmitted in a predetermined period is allocated to a predetermined time slot of the contention-free period. The device of claim 1, wherein the device is Receiving a channel search and a beacon frame in order to contact the network coordinator when the power is turned on to determine channel information (including RSSI) and a superframe structure of the network; Determining whether or not RFID wakeup support is possible by communicating with the network coordinator based on the found information; If it is determined that the RFID wake-up support is enabled, notifying the network coordination that the RFID wake-up mode is operated and switching to the power saving mode; And And if it is determined that the RFID wakeup support is not possible, setting the wakeup time according to the beacon period, and then switching to the power saving mode. The method of claim 4, wherein the determining of whether the RFID wake-up is supported Calculating a distance from the network coordinator by checking the strength of the received signal from the network coordinator by the device having the RFID tag; And determining that the RFID wakeup support is possible when the calculated distance is within the reach distance of the RFID signal, and determining that it is impossible except for the wakeup method of the Zigbee terminal device. The method of claim 4, wherein When the device sets a wake-up time in accordance with a beacon period, after switching to the power saving mode, checking whether the device is the set wake-up time; Waking up and releasing a power saving mode when the wakeup time is reached; Receiving the beacon signal from the network coordinator and checking whether there is data to be transmitted or received after the power saving mode is released; If there is data to be transmitted and received as a result of the check, communicating with a network coordinator to transmit and receive data; If there is no data to be transmitted or received, or if the data transmission and reception is completed, the wake-up method of the Zigbee terminal device further comprises the step of returning to the power saving mode after setting the wake-up time according to the beacon period .

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