KR101243927B1 - Beacon transmission method with mixed central beacon and distributed beacon - Google Patents

Abstract

Disclosed is a beacon transmission method in which a central beacon method and a distributed beacon method are mixed. The present invention relates to a mixed beacon transmission method using a combination of a central beacon method and a distributed beacon method to maintain an optimal network state by converting a beacon transmission method according to network conditions.

Description

Beacon transmission method combining central beacon and distributed beacon methods {Hybrid Beaconing method}

The present invention relates to a beacon method, and more particularly, to a mixed beacon method in a wireless personal area network (WPAN) based on a mesh network.

The present invention is derived from the research conducted as part of the IT source technology development project of the Ministry of Knowledge Economy and the Ministry of Information and Communication Research and Development. [Task management number: 2005-S-002-04, Title: Cognitive radio for improving spectrum use efficiency Technology development].

In general, WPAN periodically transmits network state information, which is called a beacon, to all or part of a network in order to transmit network state or specific device state to other devices in the network. In this case, a method of transmitting a beacon that manages the entire network mainly by a specific predefined device is called a centralized beaconing scheme, and a method of transmitting beacons by all devices in a network is a distributed beaconing scheme. This is called. An example of the central beacon method is a WPAN system of the IEEE 802.15 series, and an example of a distributed beacon method is a Wimedia system based on the ECMA-386 standard.

Figure 1a is a view showing an example of a conventional central beacon method, Figure 1b is a view showing an example of a conventional distributed beacon method.

Referring to FIG. 1A, the central beacon scheme transmits a beacon for a specific device that defines a whole network. The superframe 100 includes a beacon period section 110. It is divided into the data / control signal section 120, a beacon (B) in front of the superframe 100 is transmitted by a predetermined device, that is, a network coordinator (Network Coordinater), and the other devices Obeys beacons received from the network coordinator.

Referring to FIG. 1B, in the distributed beacon method, all devices in a network transmit beacons so that all devices sequentially transmit beacons through a beacon period section 160 in front of the superframe 150. It not only informs other devices of its network status, but also receives other device network status information. In the example of FIG. 1B, three devices in a network transmit beacons 162, 164, and 166, respectively.

In the distributed beacon method, all devices transmit a beacon once. However, as the number of devices increases, not only redundant information is transmitted but also the beacon period itself increases, which reduces the time to transmit data, thereby reducing the overall transmission efficiency. On the other hand, the central beacon method in which only a specific device transmits a beacon, when the number of devices is small, there is a problem that efficient network management is difficult because hidden nodes occur in a coverage area in which each device is included.

The technical problem to be achieved by the present invention is to overcome the shortcomings through the mixed beacon method at the time when the efficiency of each beacon method is lowered to compensate for the disadvantages of the existing beacon method and the distributed beacon method to increase the efficiency of the entire network. To provide a beacon transmission method that can be made.

In order to achieve the above technical problem, an embodiment of a beacon transmission method according to the present invention, in the beacon transmission method when two networks are combined, a specific device of any one of the two networks of the two networks Being selected as the coordinator of the entire network combined with each other; And transmitting, by the selected coordinator, the beacons to the entire two networks through the beacon main unit of the superframe.

Another embodiment of the beacon transmission method according to the present invention for achieving the above technical problem, in the beacon transmission method when the second network is coupled to the neighboring network in the first network, the second network is the first network; Receiving a portion of a data / control signal interval of a superframe of a first network; And transmitting, by the specific device of the second network, the beacon through the assigned interval.

Another embodiment of the beacon transmission method according to the present invention for achieving the above technical problem, in the beacon transmission method when two networks are combined, one of the two networks is different between the beacon main body of the superframe Receiving a section for subsequent beacon transmission in a section allocated to one network; And transmitting a beacon through a specific device of the network assigned to the section for the beacon transmission.

Another embodiment of the beacon transmission method according to the present invention for achieving the above technical problem, in the beacon transmission method when the first network operated by the central beacon method and the second network operated by the distributed beacon method is combined. The method of claim 1, further comprising: receiving a beacon through a beacon mechanism of a superframe from a network coordinator of the first network; And relaying the beacon to the second network through a partial section of the data / control signal section of the superframe.

According to the present invention, it is possible to overcome the disadvantages of the system limited to the conventional specific beacon method, and to increase the network transmission efficiency and control efficiency of the WPAN by selecting a network operation method that best matches the network situation. That is, the conventional communication system can remove the inefficiency of network management caused by fixing the beacon transmission method, and can maintain the optimal network state by converting the beacon transmission method according to the network situation.

Figure 1a is a view showing an example of a conventional central beacon method,
Figure 1b is a view showing an example of a conventional distributed beacon method,
2 is a view showing an example of a number of new beacons that can be generated by a combination of a central beacon method and a distributed beacon method,
3A to 3C illustrate examples of a superframe structure of a CC network in which a CB network and a CB network are mixed and operate based on a CB.
4A to 4C are diagrams illustrating an example of a superframe structure when a CB network and a DB network are mixed and operate as a CB (CD);
5a is a diagram illustrating a superframe structure of a network operating with a DB,
FIG. 5B is a diagram illustrating an example of a superframe structure when a device is selected as a network coordinator and operated as a CB in the DB network of FIG. 5A; FIG.
6 is a view showing an example of a mixed beacon manager that manages the mixed beacon method according to the present invention.

Hereinafter, with reference to the accompanying drawings will be described in detail a beacon transmission method mixed with a central beacon method and a distributed beacon method according to the present invention.

FIG. 2 is a diagram illustrating an example of various new beacons that may be generated by a combination of a central beacon and a distributed beacon.

Referring to FIG. 2, a new generation network and its characteristics are determined by combining networks operating through each beacon scheme to form a new network.

First, the 0th generation network (2001-2004) is a network in which the distributed beacon method (hereinafter referred to as DB) and the central beacon method (hereinafter referred to as CB) are operated.

The first generation network (2011-2014) is a network created by combining networks of the same operation method. The first generation network can determine the network operation method according to the network situation regardless of the operation method of the generation 0 network. For example, the first-generation network generated by the meeting of the CB network and the CB network can be operated not only as a CB but also as a DB.

In the present embodiment, for convenience of description, when the network generated by the CB network and the CB network is operated as the CB, it is "CC". When the network created by the DB network and the DB network is operated as the DB, it is "DD". If the network created by CB network and CB network is operated as DB, it is "CCD". If the network formed by DB network and DB network is operated as CB, it is "DDC". When the network created by meeting is operated by CB, it is designated as "CD", and when the network formed by meeting between CB network and DB network is operated by DB, it is designated as "DC".

The second generation network (2021-2022) is a network formed by the meeting of the CB network and the DB network. That is, the second generation network is a DC or CD network. The 3rd generation network (2031-2038) is a network formed by the generation of the 2nd generation network and the 0th generation network. That is, the third generation network is a DDC, CCD, DD, CC, CD, DC network.

As described above, six types of networks can be generated by combining the CB network and the DB network.

3A to 3C are diagrams illustrating examples of a superframe structure of a CC network in which a CB network and a CB network are mixed and operate on a CB basis.

Referring to FIG. 3A, a superframe is a structure in which two CB superframes meet to form a complete CB network under one device M1 command. Accordingly, in the CC network, one device M1 transmits a beacon in the CC network through the front part of the superframe.

Referring to FIG. 3B, when two CB networks are mixed, one CB network is set as a neighbor network of the remaining CB networks and operates as a dependent network. The neighboring network of the two CB networks transmits beacons and data / control signals in the network through a portion of the data / control signal transmission interval of the superframe.

Referring to FIG. 3C, two CB networks operate as CBs, but the superframe structure is similar to that of a DB by using beacon periods consecutively in one superframe. That is, although the specific device M1 of the first CB network and the specific device M4 of the second CB network operate as CBs, the two specific devices M1 and M4 transmit beacons through the BP of one superframe.

4A to 4C are diagrams illustrating an example of a superframe structure when a CB network and a DB network are mixed and operate as a CB (CD).

4A to 4C, each of the devices 412 and 414 shown in a circle represents a device operating in a DB manner, and the device 406 shown in a square shape represents a network coordinator of a CB network, and is illustrated in a triangular shape. Devices 402 and 404 represent slave devices that are under the control of network coordinator 406.

4A is an example of a case where a DB network (Network B, 410) is combined into a neighbor network of the CB network 400. At this time, the network B 410 is operated by allocating time to the neighboring portion 420 on the superframe structure and operates under the control of the network coordinator 406.

Referring to FIG. 4B, a superframe structure when two networks 430 and 440 are combined to combine two devices 412 and 414 of network B 440 operating as a DB into a slave device under the command of the coordinator 406 of the entire network. to be. In this case, the coordinator 406 of the network A 430 transmits a beacon.

Referring to FIG. 4C, when the beacon of the network coordinator 406 does not reach the neighbor network 460, the slave device S2 404 relays the beacon in the middle of the data slot.

FIG. 5A illustrates a superframe structure of a network operating as a DB, and FIG. 5B illustrates an example of a superframe structure when selecting one device as a network coordinator and operating as a CB in the DB network of FIG. 5A. One drawing.

Figure 5a is an example of a typical DB network, each device in the DB network transmits each beacon through the BP. When such a DB network operates as a CB, when a specific device M1 is elected as a network coordinator in the DB network and only the specific device M1 transmits a beacon through the BP of the superframe, the remaining devices receive the beacon. Is operated according to its beacons.

6 is a view showing an example of a mixed beacon manager that manages the mixed beacon method according to the present invention.

Referring to FIG. 6, the mixed beacon manager includes an environment monitoring unit 600, an operation mode determination unit 610, and an operation execution unit 620.

The environment monitoring unit 600 collects variables by tracking a network environment. Network environment monitoring of the environment monitoring unit 600 may determine the efficiency of the network, etc. through various conventional methods.

 The operation mode determiner 610 determines an efficient network operation mode based on the variables collected by the environment monitor 600. That is, the operation mode determination unit 610 is based on the results obtained by the environment monitoring unit 600, which operation method (ie, DDC, CCD, DD, CC, CD, DC operation method) is optimal when operating the network? To judge.

The operation execution unit 620 operates the network in a salping superframe structure according to the determined network operation mode.

The present invention can also be embodied as computer-readable codes on a computer-readable recording medium. A computer-readable recording medium includes all kinds of recording apparatuses in which data that can be read by a computer system is stored. Examples of computer-readable recording media include ROM, RAM, CD-ROM, magnetic tape, floppy disks, optical data storage devices, and the like. The computer readable recording medium can also be distributed over network coupled computer systems so that the computer readable code is stored and executed in a distributed fashion.

So far I looked at the center of the preferred embodiment for the present invention. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. Therefore, the disclosed embodiments should be considered in an illustrative rather than a restrictive sense. The scope of the present invention is defined by the appended claims rather than by the foregoing description, and all differences within the scope of equivalents thereof should be construed as being included in the present invention.

Claims (4)

delete In the beacon transmission method when the two networks are combined,
Selecting a specific device of one of the two networks as a coordinator of the entire network to which the two networks are combined; And
And transmitting, by the selected coordinator, the beacon to all devices of the two networks through the beacon inter-frame of the superframe.
Each of the two networks is a network operated by a network coordinator in a central beacon manner in which a beacon is transmitted, and the specific device is a network coordinator in which the network to which the specific device belongs is operated in a central beacon manner. In the beacon transmission method when the two networks are combined,
Selecting a specific device of one of the two networks as a coordinator of the entire network to which the two networks are combined; And
And transmitting, by the selected coordinator, the beacon to all devices of the two networks through the beacon inter-frame of the superframe.
One of the two networks is operated by the central beacon method,
The other is operated in a distributed beacon manner,
In the selecting of the coordinator, the coordinator of the network operated by the central beacon method is selected as the coordinator of the entire network. In the beacon transmission method when the first network operated by the central beacon method and the second network operated by the distributed beacon method are combined,
Receiving a beacon through a beacon main unit of a superframe from a network coordinator of the first network; And
Relaying the beacon to the second network through a partial section of the data / control signal section of the superframe.

Images