KR20130122486A - Relay network for magnetic wave communication - Google Patents

Abstract

A relay network for magnetic wave communication includes a magnetic wave communication coordinator managing a transceiving section and connecting and releasing magnetic wave communication nodes in a communication area of a magnetic wave communication low frequency band wireless network, a magnetic wave communication node which is a magnetic wave communication device except for a repeater and the coordinator in the magnetic wave communication low frequency band wireless network, and a magnetic wave communication repeater handling both a role of the coordinator and a role of the node in the magnetic wave communication low frequency band wireless network. [Reference numerals] (AA) Magnetic field area;(BB,EE,GG,II,JJ,MM,NN) Reply;(CC,DD,FF,HH,KK,LL,OO) Request

Description

Relay network for magnetic wave communication

The present invention relates to a relay network for magnetic field communication.

MFAN is a wireless network that transmits and receives information using a magnetic field signal in a low frequency band (30KHz ~ 300KHz). The operating center frequency of the wireless communication is 128KHz, and the modulation method uses binary phase shift keying (BPSK). Manchester data coding and non-return-to-zero level coding (NRZ-L) coding are used to provide data rates of several Kbps at distances of a few meters to vary the data rate.

The present invention has been made in the technical background as described above, an object of the present invention is to provide a relay network for magnetic field communication.

According to an aspect of the present invention, a relay network for magnetic field communication includes a magnetic field communication coordinator for managing connection, release, and transmission / reception intervals of magnetic field communication nodes in a communication area in a magnetic field communication low frequency band wireless network; Magnetic Field Communication In the low frequency band wireless network, the magnetic field communication node, which is a magnetic field communication device except for the magnetic field communication coordinator and repeater, and the magnetic field communication repeater which simultaneously plays the role of the node and the field communication coordinator in the magnetic field communication low frequency band wireless network. do.

According to the present invention, the magnetic field communication repeater transmits the request data of the magnetic field communication coordinator to the magnetic field communication node so that the magnetic field communication can be efficiently communicated.

Figure 1-MFAN relay network superframe structure
Figure 2-MFAN relay network
Figure 3-UID Format
Figure 4-MWCC State Diagram
Figure 5-MWCN State Diagram
Figure 6-Media access control frame format
Figure 7-Frame Control Field Format
Figure 8-Request Frame
Figure 9-Response Frame
Figure 10-Data Frame
Figure 11-Response Acknowledgment Frame
Figure 12-Data Acknowledgment Frame
Figure 13-Request Frame Payload Format
Figure 14-Join Request Data Format
Figure 15-Separation Request Data Format
Figure 16-Join Status Request Data Format
Figure 17-Data Request Data Format
Figure 18-Group Address Setup Request Data Format
Figure 19-Response Frame Payload Format
Figure 20-Join Response Data Format
Figure 21-Separate Response Data Format
Figure 22-Join Status Response Data Format
Figure 23-Data Response Data Format
Figure 24-Group Address Set Response Data Format
Figure 25-Data Frame Format
Figure 26-Response Acknowledgment Frame Payload Format
Figure 27-Join Response Acknowledgment Data Format
Figure 28-Separation Response Acknowledgment Data Format
Figure 29-Join Status Response Acknowledgment Data Format
Figure 30-Data Response Acknowledgment Data Format
Figure 31-Setup Response Acknowledgment Data Format
Figure 32-Joining Process
Figure 33-Separation Process
Figure 34-Joining Status Checking Process
Figure 35-Data Transfer Process
36-Inactive section transmission process
37-Group Address Setting Process

Advantages and features of the present invention and methods for achieving them will be apparent with reference to the embodiments described below in detail with the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Is provided to fully convey the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims. It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. In the present specification, the singular form includes plural forms unless otherwise specified in the specification. It is noted that the terms "comprises" and / or "comprising" used in the specification are intended to be inclusive in a manner similar to the components, steps, operations, and / Or additions.

A relay network for magnetic field communication using magnetic field communication according to an embodiment of the present invention will now be described in detail with reference to the accompanying drawings.

One range

This standard defines a medium access control layer for a relay network of a wireless network that transmits information using a magnetic field signal in a low frequency band. In particular, it specifies the media access control layer packet format, network topology, and data transmission structure.

This standard specifies a method of communicating in the low frequency band (30KHz to 300KHz) by forming a few Kbps wireless network within a distance of several meters. This can be applied to sensor networks, home networks and application services such as construction, agriculture and transportation.

This standard is intended to comply with the emission limits allowed for devices that may be used in an unlicensed country.

2 Related Standard

2.1 Normative References

The following specifications are essential for the application of this document. Dated specifications are to be used as cited versions, and newer versions (including amendments) apply to non-dated specifications.

MWCS-1-01: Information Technology-Magnetic Communication-Low Frequency Wireless Networks-Part 1: Air Interface, Magnetic Field Communication Convergence Forum

MWCS-1-02: Information Technology-Magnetic Communication-Low Frequency Wireless Networks-Part 2: Physical Layer, Magnetic Field Communication Convergence Forum

MWCS-1-03: Information Technology-Magnetic Field Communication-Low Frequency Wireless Networks-Part 3: Media Access Control Layer, Magnetic Field Communication Convergence Forum

2.2 Informative References

KS X ISO IEC 18000-2: Information technology-RFID for item management--Part 2: Parameters for air interface communication below 135 kHz

3 Glossary of Terms

The definitions of the main terms used in this standard are as follows.

Magnetic field communication coordinator (Magnetic Wave Communication Coordinator: MWCC) : a device that manages the magnetic field connected with the lifting and receiving sections of the communication node in the communication area from the magnetic field communication a low frequency band wireless network

Magnetic field communication node (Magnetic Wave Communication Node: MWCN) : a magnetic field communication device other than the magnetic field communication coordinator and repeater in the communication field low-frequency wireless network,

Magnetic field communication repeater (Magnetic Wave Communication Repeater: MWCR) : device that plays a role in the communication field low-frequency magnetic field act as a coordinator of communications over the wireless network nodes simultaneously

4 Abbreviation

MFAN Magnetic Field Communication Low Frequency Band Wireless Network ( Magnetic Field Area Network )

MWCC Magnetic Wave Communication Coordinator

MWCN Magnetic Wave Communication Node

MWCR Magnetic Wave Communication Repeater

5 summary

MFAN is a wireless network that transmits and receives information using a magnetic field signal in a low frequency band (30KHz ~ 300KHz). The operating center frequency of the wireless communication is 128KHz, and the modulation method uses binary phase shift keying (BPSK). Manchester data coding and non-return-to-zero level coding (NRZ-L) coding are used to provide data rates of several Kbps at distances of a few meters to vary the data rate.

Devices participating in the MFAN are divided into MWCC, MWCN and MWCR according to their role. Only one MWCC exists in one MFAN, and multiple MWCN devices form a network around the MWCC. The MWCC manages the joining, separation and release of the MWCN, and the MWCR delivers the MWCC's request data to the MWCN.

The MFAN uses a time division multiple access (TDMA) scheme. The MWCC manages the connection in the MFAN, and when the MWCN is connected, time resources are distributed by the MWCC.

MFAN technology can be applied to sensor networks, home networks and application services such as construction, agriculture and transportation.

6 Network components

6.1 General Information

Important components that make up MFAN can be divided into temporal and physical elements. The temporal element refers to a superframe including a request period, a response period, and an inactive period, and a physical element refers to a network composed of MWCC, MWCN, and MWCR. The most basic element of a physical element is a node. There are two types of nodes: MWCC, which manages the network, MWCN, which is a component of the network, and MWCR, which delivers packets.

FIG. 1 shows the structure of a superframe which is a temporal component, and FIG. 2 shows the structure of a network which is a physical component. The first node to be determined in the MFAN is MWCC, and the superframe of the MFAN is started by transmitting a request packet in the request period. The MWCC is responsible for managing the joining, separating, releasing, and transmitting / receiving periods of the MWCNs in the communication area. Since MFAN can use one channel in the communication area, only one network exists. The remaining nodes in the MFAN except MWCC become MWCN, and MWCR simultaneously plays the role of MWCN. The MWCC and each MWCN are connected 1: 1, and nodes participating in the MFAN are divided into MWCC, MWCN, and MWCR according to their roles, but all nodes may serve as MWCC or MWCN or MWCR.

6.2 Temporal elements

A temporal element that can be utilized in the MFAN is a time slot in a time division multiple access scheme. The MWCC manages a group of MWCNs that transmit data in response intervals, and timeslots are autonomously managed by MWCNs in the MFAN of the selected group.

The MFAN superplane structure is shown in FIG. 1 and consists of a request section, a response section, and an inactive section. The lengths of the request section and the response section are variable. Superframe begins by the MWCC sending a response request packet in the request period. The response request packet has information on MWCNs that can transmit the response packet during the response interval, and the MWCNs transmit the response packet during the response interval using the information in the response request packet. The MWCR may configure another superframe for the relay network during the slot period allocated during the response period. The MWCR may deliver the request packet received from the MWCC to the MWCN outside the communication area of the MWCC in the slot section request section.

6.2.1 Request interval

The request period is a period during which the MWCC transmits a response request frame having information on MWCNs for transmitting the response frame during the response period.

6.2.2 Response section

The response section is a section in which the MWCN can transmit the response frame according to the response request from the MWCC, and may be divided into several time slots according to the number of MWCNs in the MFAN. The length of each time slot varies with the length of the response frame and the length of the acknowledgment frame. The slot number is determined according to the order of the divided time slots, and the MWCN to be transmitted in each time slot is allocated by the MWCC. The MWCC allocates a response section to a specific group for use of the response section, and nodes of the assigned group autonomously transmit data frames through the response section.

6.2.3 Inactive Segment

The inactive section starts when there is no node transmitting a response packet for a predetermined time, and the section in which the nodes can transmit data without requesting MWCC. This interval lasts until the MWCC sends the request packet.

6.3 Physical elements

The physical elements of the MFAN are nodes including MWCC and MWCN in a star topology network centered on the MWCC. The MFAN is a network capable of transmitting data with each MWCN around the MWCC, and the basic component of the MFAN is a node. Nodes are divided into MWCC and MWCN according to their role. The MWCC manages the entire MFAN and there must be only one in a network. The MWCC controls the MWCN by broadcasting a response request packet to all MWCNs simultaneously. The MWCN shall send and receive response packets under the control of the MWCC. MFAN may be configured as shown in FIG.

6.3.1 MWCC

MWCC is a node that manages MFAN, and only one exists in a network. The MWCC manages and controls the MWCN using a response request packet.

6.3.2 MWCN

MWCN is a node constituting MFAN excluding MWCC, and maximum 65,519 exist in one network and transmit response packet by request packet sent by MWCC.

6.3.3 MWCR

The MWCR delivers the request packet received from the MWCC to the MWCN and the response packet received from the MWCN to the MWCC.

6.4 Address component

MFAN uses address system such as MFAN ID, UID, group address, and node address to distinguish each MWCN.

6.4.1 MFAN ID

The MFAN ID is a unique ID that distinguishes the MFAN, and its value is the only value that does not overlap with the ID of another MFAN. The value is maintained for the duration of the MFAN.

6.4.2 UID ( Unique Identifier ; UID )

The UID is a unique 64-bit identifier and consists of a group address, an IC producer code, and an IC producer serial number as shown in FIG. MWCNs are distinguished by UID.

6.4.3 Group Address

The group address is an identifier of the classified MWCN group, and can be used for the method of minimizing the collision since the data transmission request can be requested in group units during packet transmission, and has a value of 0x00 ~ 0x2F. The reserved group addresses in MFAN are shown in Table 2.

Table 1-Reserved Group Addresses

Group address Contents Remarks 0xFF All groups When selecting all groups 0xF0-0xFE Reservation

6.4.4 Node address

Node address is an identifier used to distinguish each node instead of UID. It is a 16-bit address allocated by MWCC when joining a network. The reserved node addresses in MFAN are shown in Table 2.

Table 2-Reserved Node Addresses

Node address Contents Remarks 0xFFFF All nodes When broadcasting, when sending all nodes 0xFFFE Unjoined nodes First node address of the node 0xFFF0 -0xFFFD Reservation

7 Network operation overview

7.1 General Information

The superframe of the MFAN is divided into a request section, a response section, and an inactive section. MWCC and MWCN, which are components of the MFAN, operate as follows in each section.

7.2 Request packet transmission in request interval

In the request period, the MWCC broadcasts a response request packet to all nodes. MWCNs receiving the response request packet determine whether to transmit the response packet in the response period. The MWCC may determine a group of MWCNs to be transmitted in the response period.

7.3 Response packet transmission in response interval

In the response period, the MWCN selected by the MWCC may transmit a response packet. When the MWCN transmits a response packet through the response interval, the received MWCC sends a response acknowledgment packet. The MWCN that does not receive the response acknowledgment packet continues to transmit the response packet for each time slot in the response interval until the response acknowledgment packet is received from the MWCC.

7.4 Data packet transmission in inactive section

If no MWCN sends a response packet for a certain period of time, the MWCN becomes inactive and lasts until the MWCC sends the request packet. In exceptional cases, the MWCN may transmit data without requesting the MWCC during the inactive period.

8 Network Status Overview

8.1 General Information

In MFAN, MWCN has the operation status of network formation, network join, response transmission, data transmission, master change, network separation and network release.

8.2 Network formation

The MWCC forms a network by transmitting a request packet to the MWCN in the request period. The request packet includes the MFAN ID, so that the MWCN can identify the network to which it is connecting. The minimum network duration means when only the MWCC exists and consists only of the request duration and the inactive duration.

8.3 Network joining

When the MWCC sends a join request packet through the request interval, the MWCN trying to join the MFAN determines the received packet and, if the join request packet of the desired MFAN is transmitted, transmits the join response packet through the response interval to access the MFAN. The MWCC receiving the join response packet transmits the join response acknowledgment packet to the corresponding MWCN. The MWCN receives the join response acknowledgment packet from the MWCC and the network join is completed.

8.4 Network Separation

MWCN joining MFAN can be detached from the network at the request of MWCC or voluntarily. The MWCC can be forcibly detached by sending a detach request to the MWCN according to the current network situation or service method. In case of spontaneous separation, MWCC can know the separation status of MWCN as a result of MWCC's join status request response.

8.5 Check network join status

The MWCC may ask the MWCN who joined the MFAN to see if they have joined. The MWCC sends a join status request packet to the MWCN to confirm the join status. MWCN receiving the join state request packet transmits the join state response packet so that the MWCC knows whether the join state is present. The MWCC receiving the join status response packet from the MWCN transmits the join status response acknowledgment packet to the MWCN, thereby completing the network join status check.

8.6 Data transmission

When the MWCC transmits the data response request packet through the request interval in the MFAN, the MWCNs may transmit the data response packet to the MWCC according to the requested data type. The MWCC receiving the data response packet transmits the data acknowledgment packet and the MWCN receiving the data acknowledgment packet completes the data transmission.

8.7 Change master

When there is no MWCC around the MWCN in the MFAN, the MWCN may be the MWCC.

8.8 Network off

The release of MFAN can be classified into two types: normal release by MWCN request and abnormal release caused by unexpected situation. Normal release means that the MWCC releases the network by deciding whether to release and requesting separation from the entire MWCN. Abnormal network release means when all MWCNs participating in the network are turned off at the same time, or at the same time, the network is released by moving the MWCN out of the communication area of the MFAN.

8.9 MFAN device  condition

The MFAN device states are MWCC and MWCN. When the power is turned on, the MWCC waits in the inactive section and transitions to the request section and the response section depending on whether a packet is transmitted. The MWCN is powered off until it receives a packet and then powers up as soon as the packet is received. When data transmission and reception are completed in one superframe, the device waits again with the power turned off.

8.9.1 MWCC  condition

The MWCC enters an inactive section when powered on. The MWCC which is in an inactive state enters a request section starting to send a request packet to the MWCN, and after completing the request packet transmission, enters a response section. The MWCNs receiving the request packet in the response interval transmit the response packet to the MWCC and after the MWCC receives the response packet, the MWCNs are transferred to the packet interpretation state. After receiving the request packet, the MWCC transmits an acknowledgment packet to the MWCN and maintains a response section. At this time, if all data transmission from MWCN is finished and there is no data transmission during the timeout period of MWCC, it returns to inactive section.

If an error occurs while receiving the response packet, the MWCC retransmits the request packet.

8.9.2 MWCN  condition

All MWCNs will undergo a continuous carrier check. The MWCN maintains a power off state when no carrier is detected, and enters a power on state when a carrier is detected. When the MWCC sends a response request packet, the MWCN interprets the packet and if the group address and node address do not match, the MWCN transitions back to the power off state and generates a response packet for the request if the group address and node address match. After the transmission, it is transferred to the standby state. In the standby state, when the acknowledgment packet for the own node is received, the state transitions to the power-off state. When the acknowledgment packet for the other node is received, the packet is generated and transmitted again. When the N timeout occurs within the standby state, the packet is regenerated and retransmitted. In addition, MWCN transitions to the power-off state when the (N + 1) th timeout in the standby state. If the MWCN receives the wait state request packet, it transitions to the packet interpretation state. When the system interrupt occurs in the power off state, the system moves to the power on state and when the data is received from the system, the system transitions to the packet generation state.

9 Media access control frame format

9.1 General Information

The MFAN medium access control frame consists of a frame header and a frame body. The frame header is information for data exchange between MWCNs, and the frame body is data actually exchanged between MFAN devices.

9.2 Frame format

All media access control frames are composed of a frame header and a frame body as shown in FIG.

1) Frame header: Contains control related information such as frame control information, transmitting / receiving node address, frame serial number which are necessary for data exchange between MWCNs. The information located in this section is used to distinguish the type of frame and the node that sends or receives the frame. In addition, the error of the exchanged frame is checked by using this to increase the reliability of the frame.

2) Frame body: It consists of a payload carrying data actually exchanged between MFAN devices and a frame check sequence (FCS) to check for errors in the payload.

9.2.1 Frame Headers

The frame header contains information for transmitting / receiving frames and controlling flow.

9.2.1.1 MFAN ID

The MFAN ID field is composed of 1 byte as shown in FIG. 6 and used to distinguish a network.

9.2.1.2 Frame Control

The frame control elements are composed of detailed fields such as frame type, acknowledgment method, first piece, end piece, and protocol version. The format is shown in FIG.

Each field is described as follows.

1) The frame type field consists of 3 bits. Refer to 9.3 for frame type.

2) The acknowledgment method field consists of 2 bits, and the acknowledgment method field of the acknowledgment frame indicates the type of acknowledgment frame of the acknowledgment frame, and the other acknowledgment method to be used by the receiving node for the frame.

The following shows the acknowledgment method.

a) No acknowledgment: The receiving node does not acknowledge the transmitted packet, and the transmitting node considers the transmission successful regardless of the actual result. This method is used for frames transmitted in 1: 1, 1: N that do not require acknowledgment.

b) Response acknowledgment: The node receiving the response packet responds to the transmitting node by sending a response acknowledgment packet after a short interframe space (SIFS). This acknowledgment method should only be used for frames transmitted in 1: 1.

c) Data Acknowledgment: The node receiving the data frame responds to the transmitting node by sending a data acknowledgment packet after a short frame interval. This acknowledgment method should only be used for frames transmitted in 1: 1.

3) The first fragment field is 1 bit, '1' means that the frame is the start of data descending from the upper layer, and '0' means that it is not the beginning.

4) Fragment field is 1 bit, '1' means that the frame is the end of data from upper layer, and '0' means not the end.

5) The protocol version field consists of 2 bits. The size and position are constant regardless of the system's specification version. The current value is 0, incrementing by 1 for each new version. When a specific node receives a packet higher than its version, it is discarded without notifying the sending node.

6) Reserved: This field is reserved for future use.

9.2.1.3 Serial Number

The serial number field has a length of 8 bits and indicates the serial number of the corresponding frame. The frames are numbered in sequence from 0 to 255 by the counter assigned to each packet, and from 0 when they exceed 255.

9.2.2 Frame body

The frame body has a variable length and consists of a payload and a frame check sequence. The payload has a different format according to the content of the frame type detail field in the frame control field, and the frame check sequence is used to check for errors in the frame.

9.2.2.1 Payload

The payload is the data actually exchanged between the MWCC and the MWCNs and has a variable length from 0 to 247.

9.2.2.2 Frame Inspection Sequence

The frame check sequence is 16 bits and is used to verify that the frame body was received without error. Generated using the following 16th-order Standard Generator Polynomial.

9.3 Frame Type

As shown in Table 3, the frame type is defined as four types of frames: request frame, response frame, data frame, and acknowledgment frame.

Table 3-Frame Type Values

Frame type value Contents section Request frame 0x0  Request for joining and detaching MWCC, data response, etc. request Response frame 0x1  Respond to requests for joining and separating MWCC, data, etc. reception Data frames 0x2  Used by MWCN to send data without request Inactive Acknowledgment Frame 0x3  Notification of receipt of response and data valid packets from MWCC Incoming, inactive

9.3.1 Request frame

The request frame is used when the MWCC sends a request packet to a specific MWCN in the MFAN or broadcasts information to all MWCNs in the request interval. The request frame format is shown in FIG. The acknowledgment method when broadcasting a request frame is no acknowledgment.

9.3.2 Response frame

The response frame is used to transmit a response packet of the MWCN in response to the request of the MWCC. The MWCN transmits a response packet during the response period until the acknowledgment packet is received within a specific number of times, and the response frame format is shown in FIG. 9. When the MWCN sends a response packet to the MWCC, the acknowledgment method of the response frame uses the response acknowledgment method because the acknowledgment packet must be received.

9.3.3 Data Frame

The data frame is used when the MWCN transmits data to the MWCC without requesting the MWCC in an inactive period as shown in FIG. 10.

9.3.4 Acknowledgment Frame

There are two types of acknowledgment frames: response acknowledgment frame and data acknowledgment frame. When the response acknowledgment frame is transmitted by the MWCC request frame, the MWCN receiving the request packet transmits the response packet and the MWCC receiving the response packet sends the response acknowledgment packet. The response acknowledgment frame is shown in FIG. The response acknowledgment data for the received response packet is recorded in the payload of the acknowledgment frame. The MWCC receiving the response frame responds to the transmitting MWCN by transmitting a response acknowledgment frame after a short frame interval in the response period.

The data acknowledgment frame is an acknowledgment frame for the received data packet. The MWCC responds to the MWCN transmitting the data packet by transmitting a data acknowledgment frame after a short frame interval in the inactive period. The data acknowledgment frame consists only of a frame header without a frame body as shown in FIG.

9.4 Payload  form

Payload format is configured differently according to the frame type such as request frame, response frame, data frame, acknowledgment frame.

9.4.1 Request frame

The payload format of the request frame is composed of a group address, a request code, a length, and one or more request blocks as shown in FIG. If the group address is 0xFF, request a response from the MWCN of all groups.

9.4.1.1 Group Address

The group address field consists of 1 byte and is used to request a response to a specific group. See 6.4.2 for the addressing scheme of group addresses.

9.4.1.2 Request Code

The request codes in the payload of the request frame are shown in Table 4.

Table 4-Request Frame Payload Request Codes

division Request code Contents Remarks network 0x01 Request to join Request join response to unjoined nodes 0x02 Detach request Request detached response from joined nodes 0x03 Join Status Request Request join status response from joined node 0x04-0x0F Reservation data 0x11 Data request Request data transfer to joined nodes 0x12-0x1F Reservation Set 0x21 Set group address Change group address of unjoined MWCN 0x22-0x2F Reservation Reservation 0x31-0xFF Reservation

9.4.1.3 Length

The length field consists of 1 byte and represents the sum of the request block lengths, and the value of the length field is variable depending on the length and number of request blocks.

9.4.1.4 Request Block

The data format of the request block is configured differently according to a command to be requested, and one or more request blocks may be included in the payload of the request frame.

The data format of each request block is as follows.

One) Request to join

The join request data format is shown in FIG. 14. The join request data format consists of an 8-byte UID mask. This UID mask can be used to implement a binary search algorithm.

2 ) Separation Request

The detach request data format is shown in FIG. The first two bytes are the node address of the MWCN to make a split request, and the next one is the slot number of the response interval. At this time, if the node address is 0xFFFF, request a separate response from all MWCNs corresponding to the group address.

3 ) Join Status Request

The join state request data format is shown in FIG. The first two bytes are the node address of the MWCN for which to request join status. At this time, if the node address is 0xFFFF, all MWCNs corresponding to the group address are requested to join.

4 ) Data request

The data request data format is shown in FIG. The first two bytes are the node address, the next one is the slot number, and the next one is the type of data to receive. The slot number represents the time sequence in the divided response interval and the data type is defined and used by the user according to the application.

5 ) Group address setting request

The group address setting request data format is shown in FIG. The first two bytes are the node address, the next one is the slot number, and the next one is the group address to set.

9.4.2 Response frame

The payload of the response frame holds the response data for the request. The response frame payload is shown in FIG. 19. The first 1 byte is the group address, the next 1 byte is the response code, the next 1 byte is the response data length (L), and the next L byte is the response data.

9.4.2.1 Group Address

The group address field consists of 1 byte and is used to request a response to a specific group. See 6.4.2 for the addressing scheme of group addresses.

9.4.2.2 Response Codes

The types of response codes are shown in Table 5.

Table 5-Response Prepayload Response Codes

division Response code Contents Remarks network 0x01 Join response Send UID of MWCN 0x02 Separation response Send UID of MWCN 0x03 Join status response Send node address of MWCN 0x04-0x0F Reservation data 0x11 Data response Requested Data Transfer 0x12-0x1F Reservation Set 0x21 Group Address Setting Response Send UID and group address after changing group address 0x22-0x2F Reservation Reservation 0x31-0xFF Reservation

9.4.2.3 Length

The length field consists of 1 byte and indicates the length of the response data. The length of the response data is variable according to the type of the response data.

9.4.2.4 Response data

Types of response data are divided into join response, split response, join status response, data response, and group address setting response, and consist of the following data types.

1) Joining Response

The join response data format is shown in FIG. 20. The join response data format consists of an 8-byte UID.

2 ) separation response

The separate response data format is shown in FIG. The split response data format consists of an 8-byte UID.

3 ) Joined state response

The joined state response data format is shown in FIG. The join status response data type consists of an 8-byte UID and 2 bytes of the assigned node address.

4 ) data response

The data response data format is shown in FIG. The data response data format consists of L bytes of requested data.

5 ) Group Address Setting Response

The group address setting response data format is shown in FIG. The group address setting response data format consists of an 8-byte UID to which the changed group address is applied and a set group address of 1 byte.

9.4.3 Data frames

The data frame payload contains the data to send. The data frame format consists of L bytes of data.

9.4.4 Acknowledgment Frame

The response acknowledgment frame payload has data on the received response packet. The response acknowledgment block format is shown in FIG. The first 1 byte is the group address, the next 1 byte is the response acknowledgment code, the next 1 byte is the length (L), and the next L byte is the response acknowledgment data.

9.4.4.1 Group address

The group address field consists of 1 byte and is used to request a response to a specific group. See 6.4.2 for the addressing scheme of group addresses.

9.4.4.2 Response acknowledgment code

The types of response acknowledgment codes are shown in Table 6.

Table 6-Response Verification Codes

division Acknowledgment Code Contents Remarks network 0x01 Check join response Send UIW of MWCN and assigned node address 0x02 Check detach response Send UIW of MWCN and assigned node address 0x03 Join Status Response Send UIW of MWCN and assigned node address 0x04-x0F Reservation data 0x11 Check data response Confirm data transfer to joined nodes 0x12-0x1F Reservation Set 0x21 Check group address response Send UID and group address after changing group address 0x22-0x2F Reservation Reservation 0x31-0xFF Reservation

9.4.4.3 Length

The length field consists of 1 byte and indicates the length of response acknowledgment data and varies according to the type of acknowledgment acknowledgment data.

9.4.4.4 Response acknowledgment data

The response acknowledgment data is divided into a join response acknowledgment, a split acknowledgment acknowledgment, a join state acknowledgment acknowledgment, a data acknowledgment acknowledgment, and a setup acknowledgment acknowledgment. The format of the response acknowledgment data is as follows.

1) Join response acknowledgment

The join response acknowledgment data format is shown in FIG. 27. The first eight bytes are the UID, the next two bytes are the allocation node address. If the assigned node address is 0xFFFE, which is the address of an unjoined node, the join is denied.

2 ) Acknowledgment of separation response

The detach response acknowledgment data format is shown in FIG. The first eight bytes are the UID, and the next two bytes are the node address. If separation is not allowed, the node address records the original node address. If separation is allowed, the initial node address, 0xFFFE, is recorded.

3 ) Join Status Response Acknowledgment

The joined state response acknowledgment data format is shown in FIG. The first eight bytes are the UID, and the next two bytes are the assigned node address.

4 ) Acknowledgment of Data Response

The data response acknowledgment data format is shown in FIG. The data response acknowledgment format is reserved for use by 1 byte.

5 ) Acknowledgment of setting response

The setup response acknowledgment data format is shown in FIG. The setup response acknowledgment format consists of a status check value of one byte.

Status check values are shown in Table 7.

Table 7-Setup Status Check Values

value Contents 0x00 Change completed 0x01 Change failed 0x02-0xFF Reservation

10 Media access control function

10.1 General Information

In the MFAN's media access control layer, joining and separation, and joining status checking procedures are used to manage the network. Types of data transmission include transmission in response period and transmission in inactivity period. And it provides group address setting function for group management of MWCN.

10.2 Network Joining and Separation

In order for the MWCN to communicate with the MWCC, it must first join the MFAN. Basically, each MWCN looks for a MFAN that has already been formed, and if there is an existing MFAN, joins it. If not, the MWCN forms a new MFAN. (Forming a new MFAN means sending request packet periodically.) However, depending on the performance of the node itself, it does not form MFAN and remains as MWCN continuously. Can form a new MFAN. In this case, if the existing MFAN is formed, there is only one frequency channel and thus abandon network formation.

10.2.1 joining

If the MWCC sends a join request packet to the MWCN that has not yet joined the MFAN in the request interval, the MWCN transmits the join response packet to the MWCC through the response interval. The MWCC determines whether the MWCN joins the MFAN and informs of the result through the join response acknowledgment packet. In the case of allowing the join, the node address assigned to the join response acknowledgment packet is included. In case of rejection, the initial node address 0xFFFE is recorded. As shown in FIG. 32, if the MWCC has not received or received the join response packet but the MWCN attempts to join due to the data error of the join response acknowledgment packet, the MWCC does not receive the join response acknowledgment packet. A join response packet is transmitted for each time slot. Joining is complete when the MWCN receives the Join Response Acknowledgment Packet from the MWCC.

10.2.2 detach

When the MWCC sends a separate response request packet to the MWCN joined the MFAN in the request interval, the MWCN transmits a separate response packet to the MWCC through the response interval. The MWCC determines whether to detach the MMFC of the MWCN and informs the result of the MWCN through the separation acknowledgment packet. If the separation is allowed, the node response is recorded with the initial node address 0xFFFE in the separation response acknowledgment packet. If the separation is rejected, the original node address is recorded. As shown in FIG. 33, if the MWCC has not received or received the split response packet, but the MWCN attempts to split it with the data error of the split acknowledgment packet, it does not receive the split response acknowledgment packet and continues to receive the split acknowledgment packet. A separate response packet is sent for each time slot. Separation is complete when the MWCN receives a detach acknowledgment packet from the MWCC.

10.2.3 Check join status

When the MWCC sends a join status response request packet to the MWCN joining the MFAN in the request interval, the MWCN transmits the join status response packet to the MWCC through the response interval. The MWCC checks the joining status of the MFAN of the MWCN and transmits the joining status response acknowledgment packet. As shown in FIG. 34, when the MWCC has not received or received the join status response packet but the MWCN to send the join status response packet due to the data error of the join status response acknowledgment packet does not receive the join status response acknowledgment packet, the join status response is received. Continue joining response packets every time slot until an acknowledgment packet is received. When the MWCN receives the join status response acknowledgment packet from the MWCC, the join status response is completed.

10.3 Data transmission

The sections in which data can be transmitted in the MFAN are the response section and the inactive section. In the response period, data can be transmitted by the request of the MWCC, and in the inactive period, data can be transmitted without the request of the MWCC.

10.3.1 Transmission in response interval

When the MWCC sends a data response request packet to the MWCN joining the MFAN in the request interval, the MWCN transmits the data response packet through the response interval. The MWCC transmits a data acknowledgment packet after receiving the data of the corresponding MWCN. As shown in FIG. 35, if the MWCC has not received or received the data response packet but the MWCN to send the data response packet due to the data error of the data acknowledgment packet does not receive the data acknowledgment packet, it continues until the data acknowledgment packet is received. Send a data response packet every time slot. When the MWCN receives the data acknowledgment packet from the MWCC, the data transmission is completed.

10.3.2 Transmission in inactive section

If the MWCN does not send a response packet for a specific time, it becomes an inactive section and this section continues until the MWCC sends a request packet. In exceptional cases, the MWCN may transmit data without requesting the MWCC during the inactive period. As shown in FIG. 36, when a system interrupt occurs, the MWCN may transmit data without a request from the MWCC. If the MWCC does not receive the data of the MWCN, the data is retransmitted until the data is received. When the data reception of the MWCN is completed, the MWCC sends a data acknowledgment packet to the MWCN, and the data transmission is completed when the MWCN receives the data acknowledgment packet.

10.4 Set group address

When the MWCC sends a group address configuration response packet to the MWCN joining the MFAN in the request interval, the MWCN transmits the group address configuration response packet through the response interval. The MWCC checks the group address setting state of the MWCN and transmits a group address setting response acknowledgment packet. As shown in FIG. 37, if the MWCC has not received or received the group address setting response packet but the MWCN to send the group address setting response packet due to the data error of the group address setting response acknowledgment packet does not receive the group address setting response acknowledgment packet. The group addressing response packet is continuously transmitted every time slot until the group addressing response acknowledgment packet is received. When the MWCN receives the group address setting response acknowledgment packet from the MWCC, the group address setting is completed.

Claims (1)

Magnetic field communication coordinator for managing connection, release and transmission / reception intervals of magnetic field communication nodes in a communication area in a low frequency band wireless network;
A magnetic field communication node, which is a magnetic field communication device except for a magnetic field communication coordinator and a repeater, in a low frequency band wireless network;
Magnetic Field Communication Including a magnetic field communication repeater that simultaneously plays the role of a node and a magnetic field communication coordinator in a low frequency band wireless network
Relay network for magnetic field communication.

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