WO2016072564A1

WO2016072564A1 - Transmission section allocation device and allocation method using distributed multi-coloring algorithm of wireless body area network

Info

Publication number: WO2016072564A1
Application number: PCT/KR2015/001594
Authority: WO
Inventors: 조진성; 이지은; 유재현
Original assignee: 경희대학교 산학협력단
Priority date: 2014-11-03
Filing date: 2015-02-17
Publication date: 2016-05-12
Also published as: KR101577783B1

Abstract

A transmission section allocation device using a distributed multi-coloring algorithm, according to the present invention, comprises: an overlapping information collection unit collecting overlapping information between two or more wireless body area networks (WBANs) so as to detect an overlapping state between the two or more WBANs; a priority calculation unit for calculating priorities of the two or more WBANs on the basis of a preset traffic type priority level and traffic volume priority level; and a transmission section allocation unit for repetitively mapping and allocating a color corresponding to a time slot on the basis of the overlapping state such that overlapped WBANs have different colors.

Description

Transmission Segmentation Allocation Device and Allocation Method Using Distributed Multi-Coloring Algorithm of Wireless Body Area Network

The present invention relates to a wireless body area network (WBAN), and more particularly, to a technique for allocating a transmission section of a WBAN.

A wireless body area network (WBAN) refers to a communication technology in which various wireless devices implanted in or attached to a human body or which are attached to the human body are performed in an area of 3M or less around the human body. WBAN is used to transmit information about a user's body or information collected from the user's body, and the field of application is being expanded to various entertainments. However, in an area with high density of users with WBANs, transmission intervals between user-specific WBANs may overlap and collisions may occur. If a collision occurs due to overlapping transmission intervals between WBANs for each user, data transmission of a device configuring the WBAN may fail or an error may occur. In order to solve the overlapping problem of the WBAN, a conventional method has been used to give priority to individual WBANs or reduce traffic. However, in this solution, since the high priority WBAN occupies the transmission section, the WBAN having a low priority may not be properly allocated the transmission section.

Republic of Korea Patent Publication No. 10-2014-0037683 discloses a method for solving the problem of overlapping the transmission interval between the WBAN. However, the Republic of Korea Patent Publication No. 10-2014-0037683 includes the content of allocating the transmission interval of the WBAN using the Cournot competition, but where the overlap occurs due to high WBAN density, equally to a number of WBAN It is difficult to assign a transmission interval.

An object of the present invention is to provide a transmission interval allocation apparatus and an allocation method for reducing delay and loss of data transmitted by a WBAN by avoiding mutual interference in a space where a plurality of WBANs are concentrated.

The transmission section allocation apparatus using the distributed multi-coloring algorithm according to the present invention collects overlapping information between two or more Wireless Body Area Networks (WBANs), and determines an overlapping state between two or more Wireless Body Area Networks. The superposition information collector, a priority calculator that calculates priorities of two or more wireless body area networks based on a preset traffic type priority level and a traffic volume priority level, and a color corresponding to the time slot based on the superimposed state. It includes a transmission section allocator for repeatedly mapping and assigning overlapping wireless body area network to have different colors.

The overlapping information collecting unit collects 2-hop overlapping information through 2-hop message exchange between two or more wireless body area networks, and simultaneously exists at 1-hop and 2-hop distances according to the collected overlapping information. The network is determined to be in an overlapping state. In addition, the traffic type priority level may be set through weights assigned according to the type of data transmitted from the wireless body area network.

The priority calculator calculates a priority by averaging traffic type priority levels and traffic volume priority levels of one or more sensors included in each of the two or more wireless body area networks. Priority is

Can be calculated by

The transmission section allocator generates a distributed multi-coloring algorithm table by mapping a wireless body area network with a color sequence according to randomly allocated color and overlapping information, and generates a distributed multi-coloring algorithm table based on the generated distributed multi-coloring algorithm table. If a color is assigned and the same color is assigned to the 1-hop wireless body area network, then one of the wireless body area networks can be placed at rest based on priority.

The transmission section allocator may perform an initial coloring process such that the wireless body area network overlapping the colors corresponding to the time slots have different colors before performing the mapping process.

In the transmission interval allocation method using the distributed multi-coloring algorithm according to the present invention, the step of collecting overlapping information between two or more Wireless Body Area Networks (WBANs), a preset traffic type priority level, and a traffic volume priority Calculating priorities of the at least two wireless body area networks based on the level, randomizing the colors corresponding to the time slots in each of the at least two wireless body area networks such that the one-hop wireless body area network has different colors; And repeatedly assigning a color corresponding to the time slot so that the overlapped wireless body area networks have different colors and assigning the same to the wireless body area network.

An apparatus and method for allocating a transmission interval using a distributed multi-coloring algorithm of a wireless body area network according to the present invention can prevent interference between WBANs in a densely populated region of WBANs, and allocate an optimal transmission interval to each WBAN so that the WBAN Can reduce data loss and transmission delay.

1 is a block diagram showing an embodiment of a transmission interval allocation apparatus using a distributed multi-coloring algorithm of a human body wireless network according to the present invention.

2A is a block diagram illustrating an example of an overlapping state of a transmission interval allocation apparatus using a distributed multi-coloring algorithm of a human body wireless network according to an embodiment of the present invention.

FIG. 2B is a diagram for explaining a process of applying a distributed multi-coloring algorithm of a human body wireless network according to an embodiment of the present invention to the example of FIG. 2A.

FIG. 3 is a diagram for comparing a distributed multi-coloring algorithm and a conventional coloring algorithm of an apparatus for allocating a transmission interval using a distributed multi-coloring algorithm of a human body wireless network according to an embodiment of the present invention.

4 is a flowchart illustrating a transmission section allocation method using a distributed multi-coloring algorithm of a human body wireless network according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Terms and words used herein are terms selected in consideration of functions in the embodiments, and the meaning of the terms may vary according to the intention or custom of the invention. Therefore, the terminology used in the embodiments to be described later, according to the definition when specifically defined in the present specification, if there is no specific definition should be interpreted as meaning generally recognized by those skilled in the art.

Referring to FIG. 1, the apparatus for allocating a transmission interval 100 using a distributed multi-coloring algorithm of a human body wireless network according to the present invention includes an overlapping information collecting unit 110, a priority calculating unit 120, and a transmission interval allocating unit 130. ).

The Graph Coloring algorithm is a problem in which each part of the graph is colored, such as vertices or sides, and there are various restrictions on the method of coloring. In the graph coloring algorithm, if each node has information of neighboring nodes, this information can be collected to define the coexistence situation as a graph. The Distributed Multi-Coloring Algorithm algorithm constructs a set of WBANs with low interference because they are not adjacent through a graph coloring algorithm in a plurality of WBAN situations. In the standard, a set of WBANs alternates between an active section and an inactive section in accordance with an active time synchronization. In the transmission section allocating apparatus 100 using the distributed multi-coloring algorithm of the human body wireless network according to the present invention, the overlapping N WBANs operate based on a timeline. The coordinator of each WBAN exchanges messages between 1-hop and 2-hop during synchronization, and all colors are mapped to integers starting with 1.

The overlapping information calculating unit 110 collects overlapping information between two or more WBANs. Overlapping information between two or more WBANs can be collected from 2-hop information between WBANs. Assuming each WBAN is one node, one WBAN broadcasts its information to a neighboring node (another WBAN). Then, the WBAN receiving the information transfers the received information again. Through this, each node gets two-hop overlap information. The overlapping information calculating unit 110 collects overlapping information between two hops through information exchange between two or more WBANs. The overlapping information calculator 110 may check the overlapping state (interference) between two or more WBANs through the collected overlapping information. The overlap state means the number of completely overlapping forms. The overlapping information calculator 110 may generate an overlapping diagram according to the overlapping state identified through the overlapping information. The process of setting the overlapping state through the overlapping information calculating unit 110 through the overlapping information will be described later in FIGS. 2A and 2B.

The priority calculator 120 calculates a priority between two or more WBANs based on the traffic type priority level and the traffic volume priority level.

Table 1

Example of traffic type priority level

Degree	Traffic Type Priority	Traffic Type
Lowhigh
		0	Backgtound (BK)
		One	Best Effort (BE)
		2	Excellent Effort (EE)
		3	Control Load (CL)
		4	Video (VI)
		5	Voice (VO)
		6	Medical data / Network Control
7		Emergency / Medical Event Report

Table 1 shows an example of traffic type priority levels of nodes constituting the WBAN. One WBAN may consist of one or more nodes. The user may reflect the process of setting the priority level of the traffic type according to the type of the WBAN and the type of the current place. As in the example of Table 1, the traffic type priority may be set through weights given according to the type of data delivered by the WBAN. For example, a WBAN that delivers an emergency or medical event, or delivers medical data or network control data can be given a high priority. On the other hand, low priority may be given to background data or best effort data. The traffic type priority level shown in Table 1 is one example that is not limited to the present invention, and may be set to another priority according to the type and environment of the WBAN.

TABLE 2

Example of traffic volume priority levels

Degree	Traffic Volume Priority	Traffic Volume
Lowhigh
		0	0-50kb
		One	51-100kb
		2	101-150kb
		3	151-200kb
4		201-250kb

Table 2 shows an example of traffic volume priority levels. The traffic volume priority level shown in Table 2 is a priority level set based on the amount of data transmitted from each node constituting the WBAN. The traffic volume priority levels of Table 2 are set as one embodiment and may be set differently according to the type and environment of the WBAN.

Equation 1

Each WBAN priority may be calculated by Equation 1. In Equation 1, Wn represents a priority, m represents the number of sensors (nodes) constituting the WBAN, p1 _i represents a traffic type priority level of an individual node, and p2 _i represents a traffic volume priority level of an individual node. The priority calculator 120 calculates a priority of the WBAN based on an average of the sum of the traffic type priority level p1 _{i of} each node and the traffic volume priority level p2 _i of each node.

Before allocating the transmission interval to the two or more WBANs using the graph coloring algorithm, the transmission section allocator 130 first allocates the colors included in the color palette to each of the two or more WBANs without information exchange. Perform the coloring process. The color palette represents each transmission section available in the system in one color, and different colors included in the color palette represent each transmission section available. The color palette indicating the available transmission interval may be represented by an abbreviation indicating color for convenience. The size of a color palette, which is a collection of colors, is fixed at k, the number of colors given. In addition, the color palette may be represented by mapping the color to an integer starting from 1. The number k of a given color means the total time for the entire network to transmit data once, i.e. the number of timeslots. Each color included in the color palette means one timeslot. For example, if the WBAN is Time Division Multiple Access (TDMA), each color (e.g., R / G / B / Y) is one time slot of TDMA, where R is time1, G Indicates that they do not overlap with each other using time2.

In this process, when the same color is allocated between one-hop neighbors, the transmission section allocator 130 compares the priority calculated by Equation 1 to have a color assigned with a WBAN having a high priority, Randomly assigns colors back to unassigned WBANs. As an example, when the transmission section allocator 130 assigns the same color to 1-hop neighbors and has the same priority, randomly assigns numbers 1 to 100 to the WBANs to which the same color is assigned, respectively, so that the number is low. You can assign a new color to the WBAN. If the same integer is assigned, it can be repeated again within twice the previous range. The transmission section allocator 130 repeats the above process and allocates initial colors to all WBANs by allocating different colors to overlapping WBANs.

Next, the transmission section allocator 130 performs a multi-coloring process of dynamically allocating a transmission section to two or more WBANs to which an initial color is allocated using a distributed multi-coloring algorithm. The transmission section allocator 130 defines the number of intersections of 1-hop information and 2-hop information collected from two or more WBANs in an overlapping degree. The transmission section allocator 130 generates the color sequence of each WBAN based on this, sets the color order in the order of the generated sequence, and assigns the color sequence to the WBAN. The color sequence means that the colors representing the time slots are repeatedly listed in the same order. In the process of assigning colors according to the color sequence, if the same color is allocated between 1-hop WBANs, priority is compared to occupy an advantage. Then, the transmission section allocator 130 uses the color assigned in the high priority WBAN, and the low priority WBAN does not receive the color in the sequence and pauses data transmission. Exceptionally, if the initial color of the 1-hop WBAN is the same as the overlap to which it belongs, it may be randomly assigned colors again.

TABLE 3

Table 3 shows a distributed multi-coloring algorithm of the transmission section allocator 130. The distributed multi-coloring algorithm determines (1) the initial color of the nth WBAN by c, initializes the count variable to zero (2), and initializes the variable for calculation to zero (3). Then, the number jumped by the degree of overlap to the initial value is assigned (5) so that it waits for the degree of its own overlap and is assigned a color. For example, C1 = 2, O1 = 4-> 2,6,10,14,18. A more detailed distributed multi-coloring algorithm and a transmission interval allocation process using the same will be described later in FIGS. 2A and 2B.

The transmission section allocating apparatus 100 according to the present invention allocates different colors to the overlapping WBANs through the above-described process. Each color represents one different time slot. In addition, the transmission interval allocation apparatus 100 according to the present invention allows different transmission intervals to be always allocated between overlapping WBANs through the above-described distributed coloring algorithm. Thus, each WBAN can forward packets without interfering with each other.

2A and 2B, the example of FIG. 2A includes a total of 11 WBANs, with each circle representing the network range of each WBAN. The overlapping information collecting unit 110 collects overlapping information through two-hop message exchange of the WBAN, and checks the overlapping state between 11 WBANs.

Table 4

Use of Overlapping Information

	1-hop	2-hop	Nested WBAN	Nesting
WBAN No. 1	2,3,4	2,3,4,5	2,3,4	4
No. 2 WBAN	1,3,4	1,3,4,5	1,3,4	4
3 WBAN	1,2,4,5	1,2,4,6,7	1,2,4	4
4th WBAN	1,2,3	1,2,3,4,5	1,2,3	4
WBAN No. 5	6,7,3	5,6,7,8,1,2,4	6,7	3
WBAN No. 6	5,7,8	3,5,7,9,10,11	5,7	3
7 WBAN	5,6	3,5,6,8	5,6	3
No. 8 WBAN	6,9,10,11	5,7,9,10,11	9,10,11	4
WBAN No. 9	8,10,11	6,8,10,11	8,10,11	4
WBAN No. 10	8,9,11	6,8,9,11	8,9,11	4
11 WBAN	8,9,10	6,8,9,10	8,9,10	4

In the example of FIG. 2A, Table 4 shows overlapping information and a degree of overlap calculated by the overlapping information calculating unit 110. Looking at WBAN No. 1 in Table 4, WBAN Nos. 2, 3, and 4 exist at 1 hop distance of WBAN No. 1, and WBANs 2, 3, 4, and 5 exist at 2 hop distances. WBANs 1, 2, and 3 exist simultaneously at 1 hop distance and 2 hop distance from WBAN 1. In order to be in both WBAN 1 and 1 hop / 2 hop distances, they must overlap each other. Therefore, it can be seen that WBAN No. 1 and WBAN Nos. 2, 3, and 4 are overlapping states (overlapping relationships). That is, the overlapping information calculating unit 110 may determine that the WBAN corresponding to the intersection of 1 hop and 2 hop is in the overlapping state according to the overlapping information. Since WBAN 1, 2, 3, and 4 are overlapped, the overlap may be 3 + 1 = 4. Through this same process, the degree of overlap between the 11 WBANs can be known.

Table 2b is a diagram showing the degree of overlap between the 11 WBAN in the form of diagram based on the degree of overlap according to Table 4. In FIG. 2B, a connection line between WBANs indicates that two WBANs overlap each other.

The transmission section allocator 130 assigns initial colors to each of the WBANs 1 to 11 through an initial coloring process. In FIG. 2B, the number k of colors included in the color palette is assumed to be 4, and the colors included in the color palette are assumed to be red (R), green (G), blue (B), and yellow (Y).

Table 5

Distributed Multi-Coloring Algorithm Table

sequence	R	G	B	Y	R	G	B	Y	R	G	B	Y	R	G	B	Y
First group	4	2	One	3	4	2	One	3	4	2	One	3	4	2	One	3
Second group	6	7	5	6	7	5	6	7	5		7		6	7	5	6
Third group	11	8	9	10	11	8	9	10	11	8	9	10	11	8	9	10

Table 5 shows a distributed multi-coloring algorithm table indicating colors assigned to WBANs 1 to 11 by applying the distributed multi-coloring algorithm. For convenience of description, it is divided into the first group of 1/2/3/4 WBAN, the second group of 5/6/7 WBAN and the third group of 8/9/10/11 WBAN according to the overlapping degree. It was.

The transmission section allocator 130 generates a color sequence of each WBAN in the group, and allocates the order of colors in the order of the generated color sequences. The transmission section allocator 130 repeatedly allocates a color corresponding to the time slot for each group.

The transmission section allocator 130 first performs an initial coloring process through random selection. The transmission section allocating unit 130 arbitrarily assigns colors to all WBANs in a color palette made within a given number of colors k. After having the color, each WBAN may broadcast its color to the transmission section allocator 130. And, if the same color is allocated to the 1-hop neighboring WBAN of the WBAN, the transmission section allocator 130 compares the priorities of the WBANs calculated by the priority calculator 120 to assign a new color to the WBAN having a lower priority. Can be assigned. By repeating the same process, the transmission section allocator 130 may assign initial colors to all WBANs so that the same colors are not allocated to the overlapping WBANs.

Through the initial coloring process, the first to fourth WBANs included in the first group group are assigned initial colors in the order of B, G, Y, and R. WBANs 5 to 7 included in the second group are assigned initial colors in the order of B, R, and G. BBs 8 to 11 included in the third group group are G, B, Initial colors are assigned in the order of Y and R. Then, the transmission section allocator 130 generates a distributed multi-coloring algorithm table as shown in Table 5 by matching WBAN for each group with a table that sequentially repeats the colors included in the color palette based on the overlapping degree.

Looking at the color sequence of Table 5, the colors included in the color palette are repeatedly arranged in the order of R, G, B, and Y to generate a color table. In other words, four colors are repeatedly assigned by forming one color period in the order of R, G, B, and Y. The order of colors is arbitrarily assumed for convenience of description, and the order of colors can be freely set. Then, as shown in Table 5, the transmission section allocator 130 waits for the overlapping degree of the corresponding WBAN according to the color sequence (color order), and then continuously assigns colors.

The first color WBAN to the fourth WBAN are assigned initial colors in the order of B, G, Y, and R, respectively. When this is matched with the color tables repeatedly listed in the order of R, G, B, and Y, the colors R, G, B, and Y are matched in the order of No. 4, No. 2, No. 1, No. 3, and WBAN. Since the overlap of WBAN Nos. 1 to 4 is 4, which is equal to the number of colors k (= 4), the same color is allocated in one color period. WBAN Nos. 5 to 7 are respectively assigned to B, R, and G. The initial colors are assigned in the order of. If this is matched with the color tables repeatedly listed in the order of R, G, B, and Y, the colors R, G, B, and Y are matched in the order of WBAN Nos. 6-7. Since the superposition of WBAN Nos. 5 to 7 is 3, which is smaller than the number of colors k (= 4), multi-color assignment is possible in one color period. Looking at Table 5, it can be seen that WBAN No. 6 is assigned R and Y within one color period.

In the table of Table 5, the colors did not match the WBAN of the second group in the 10th and 12th of the second group. The 10th position of the second group should be assigned color G to WBAN No. 6, but WBAN No. 8, which is in a 1-hop relationship with WBAN No. 6, is continuously assigned G. Therefore, only one WBAN among WBAN # 6 and # 8 WBAN located in the 1-hop relationship may be assigned the color G. if. Assuming that the priority of WBAN No. 6 is lower than the priority of WBAN No. 8, the transmission section allocator 130 assigns color G to WBAN having a high priority. In addition, the transmission section allocator 130 does not assign color to the WBAN No. 6 so that the WBAN No. 6 does not transmit data during a sequence, thereby creating a rest state. In the sequence in which WBAN # 5 also needs to be assigned color Y, since WBAN # 3 is assigned the same color Y, the transmission section allocator 130 allocates Y to # 3 WBAN having a higher priority by comparing the priorities. During the sequence, WBAN # 5 makes no data at rest. Through such a process, the transmission interval allocation apparatus 100 according to the present invention may allocate a limited transmission interval through a distributed multi-coloring algorithm to prevent overlap between a plurality of WBANs and to minimize a rest state of the WBANs. .

Table 6

Example of color sequence

# of WBAN (vertex)	Sequence
# of WBAN (vertex)	k = 4 (R, G, B, Y)	k = 5 (R, G, B, Y, O)
no. 1	BBBB	BGROY
No.2	GGGG	GROYB
number
3	YYYY	YBGRO
4 times	RRRR	ROYBG
5 times	BGRY	BRYOG
6th	RYBG	RYGOB
7th	GRYB	GOBRY
8th	GGGG	GROYB
9th	BBBB	BGROY
10th	YYYY	YBGRO
11th	RRRR	ROYBG

Table 6 shows an example of the color sequence generated in the transmission section allocator 130 when the color number k of the color palette is 4 and 5 in the embodiment of FIG. When the color number k of the color palette is 4, colors are assigned to the same color sequence as described above. When the color number k is 4, the color 1/2/3/4 WBAN belonging to the first group and the 8/9/10/11 WBAN belonging to the third group have the same number as the color number, The same color can be fixedly assigned without changing. On the other hand, WBANs 5/6/7 belonging to the second group may be assigned with the color continuously changed. When the number of colors (k) of the color palette is 5, the colors are assigned to the WBANs according to the color sequence of Table 5. 3 is a diagram illustrating a comparison between a distributed multi-coloring algorithm and a conventional coloring algorithm of a transmission section allocation apparatus using a distributed multi-coloring algorithm of a human body wireless network according to an embodiment of the present invention.

Referring to FIG. 3, it is assumed that the color number k = 4 of the color palette in order to compare the difference between the results of applying the distributed multi-coloring algorithm and the conventional coloring algorithm according to the present invention. A transmission interval allocation apparatus using a distributed multi-coloring algorithm of a human body wireless network according to the present invention can increase spatial utilization ratio by allocating colors (transmission intervals) to two or more WBANs using a distributed multi-coloring algorithm. have.

In the color table 301 to which the distributed multi-coloring algorithm according to the present invention is applied, as shown in FIG. 2, the 10th position of the second group should be assigned color G to WBAN No. 6, but WBAN No. 6 and 1- WBAN No. 8 in a hop relationship is continuously assigned G. Therefore, only one WBAN among WBAN # 6 and # 8 WBAN located in the 1-hop relationship may be assigned the color G. if. Assuming that the WBAN included in the second group has a lower priority than the WBAN included in the first group and the third group, the transmission section allocator has a lower priority than that of the WBAN 6 in comparison with the 8 WBAN. Assign color G to WBAN # 8. And, the transmission section allocator does not assign color to WBAN No. 6, so that WBAN No. 6 during a sequence does not transmit data. In the sequence where WBAN No. 5 also needs to be assigned color Y, since WBAN No. 3 is assigned the same color Y, the transmission section allocator 130 allocates Y to WBAN No. 3 by comparing the priorities and corresponding sequence. 5 times, WBAN puts the data in a restless state. That is, the 10th WBAN of the second group and the 5th WBAN of the 12th group have the same color as the WBANs in the 1-hop relationship, and therefore, colors are not assigned according to priority and do not transmit data in the sequence. .

Under the same conditions, the color table 302 to which Complete Coloring is applied is repeated in the same group as the first group and the third group, thereby repeating the second group in the WBAN included in the second group in the fourth sequence of every period. No color is assigned and no data is sent. Compared with the distributed multi-coloring algorithm of the present invention, complete coloring results in unallocated colors (idle resources in the transmission section) within the same sequence. Similarly, in the case of the color table 303 to which Incomplete Coloring is applied, unallocated colors are generated like Complete Coloring. In particular, in the case of incomplete coloring, if the number of colors k is the same as the minimum number of colors required by the network, the same result as the complete coloring is obtained. The color table 302 with complete coloring and the color table with incomplete coloring ( 303) is the first assigned color is fixedly assigned. Therefore, in the second group where the degree of overlap is smaller than the number of colors, since only three WBANs exist, one color remains and an idle resource of a transmission section is generated. On the other hand, in the color table 301 to which the distributed multi-coloring algorithm according to the present invention is applied, the predetermined color is not fixed but progressed by a color sequence. Therefore, in the case of the second group in which the degree of overlap is smaller than the number of colors, R and Y colors may be allocated to WBAN No. 6. That is, in the present invention, as in the color table 302 to which the complete coloring is applied and the color table 303 to which the incomplete coloring is applied, fixed idle resources do not occur, and colors are overlapped at a one-hop distance. Colors are not assigned only in the 10th / 12th. Accordingly, the transmission section allocating apparatus 100 according to the present invention can increase the space utilization rate of the WBAN transmission section by minimizing idle resources in the transmission section by using a distributed multi-coloring algorithm. 4 is a flowchart illustrating a transmission section allocation method using a distributed multi-coloring algorithm of a human body wireless network according to an example.

Referring to FIG. 4, in the transmission section allocation method using the distributed multi-coloring algorithm of the human body wireless network according to an embodiment of the present invention, the transmission section allocation apparatus first collects overlapping information between two or more WBANs (401). Overlapping information between two or more WBANs can be collected from 2-hop information between WBANs. Assuming each WBAN is one node, one WBAN broadcasts its information to a neighboring node (another WBAN). Then, the WBAN receiving the information transfers the received information again. Through this, each node gets two-hop overlap information. The transmission section allocation apparatus collects two-hop overlapping information through information exchange between two or more WBANs. The apparatus for allocating transmission intervals calculates an overlapping degree between two or more WBANs through the collected overlapping information (402).

Next, the transmission section allocation apparatus calculates a priority between two or more WBANs based on a preset traffic type priority level and a traffic volume priority level (403). Traffic type priority levels and traffic volume priority levels are described in Table 1 and Table 2 above. The user may reflect the process of setting the priority level of the traffic type according to the type of the WBAN and the type of the current place. As in the example of Table 1, the traffic type priority may be set through weights given according to the type of data delivered by the WBAN. The traffic volume priority level shown in Table 2 is a priority level set based on the amount of data transmitted from each node constituting the WBAN. The transmission section allocation apparatus may calculate the priority based on Equation 1 described above. The transmission section allocation apparatus calculates the priority of each WBAN based on an average of the sum of the traffic type priority levels of the individual nodes and the traffic volume priority level of the individual nodes.

Next, the transmission section allocating apparatus performs an initial coloring process of randomly allocating colors included in a color palette to each of two or more WBANs based on the degree of overlap (404). The color palette represents each transmission section available in the system in one color, and different colors included in the color palette represent each transmission section available. The color palette indicating the available transmission interval may be represented by an abbreviation indicating color for convenience. The size of a color palette, which is a collection of colors, is fixed at k, the number of colors given. In addition, the color palette may be represented by mapping the color to an integer starting from 1.

In this process, the transmission section allocating apparatus has a color assigned with a WBAN having a high priority by comparing the priority calculated by Equation 1 when the same color is allocated among one-hop neighbors based on the overlapping degree. In addition, randomly assigns colors back to WBANs that have not been assigned a color. As an example, the transmission section allocation apparatus randomly assigns a number from 1 to 100 to each WBAN assigned the same color when the same color is assigned among the 1-hop neighbors and has the same priority, so that a new WBAN is assigned to the lower number. You can assign colors. If the same integer is assigned, it can be repeated again within twice the previous range. The transmission section allocating apparatus repeats this process and allocates initial colors to all WBANs by allocating different colors to overlapping WBANs.

Next, the transmission section allocation apparatus performs a multi-coloring process of dynamically allocating a transmission section to two or more WBANs to which an initial color is allocated using a distributed multi-coloring algorithm (405). The transmission section allocation apparatus defines a case where the 1-hop information and 2-hop information collected from two or more WBANs intersect. The transmission section allocation apparatus generates a color sequence of each WBAN based on this, and assigns the color sequence to the WBAN by setting the color order in the order of the generated sequence. In the process of assigning colors according to a sequence, if the same color is allocated between 1-hop WBANs, the priority is compared to occupy an advantage. In addition, the transmission section allocator uses the color assigned in the high priority WBAN, and the low priority WBAN does not receive the color in the sequence and pauses data transmission. Exceptionally, if the initial color of the 1-hop WBAN is the same as the overlap to which it belongs, it may be randomly assigned colors again. The more detailed distributed multi-coloring algorithm and the transmission interval allocation process using the same are applied to the techniques described in FIGS. 2A and 2B. The WBAN to which color is assigned transmits and receives data through a transmission section corresponding to the assigned color according to the color sequence. In the present invention, different colors mean different timeslots. In addition, the transmission interval allocation method according to the present invention allows different transmission intervals to be always allocated between overlapping WBANs through the above-described distributed coloring algorithm. Thus, each WBAN can forward packets without interfering with each other.

The present invention including the above-described contents can be produced by a computer program. And code and code segments constituting the program can be easily inferred by a computer programmer in the art. In addition, the written program may be stored in a computer-readable recording medium or information storage medium, and read and executed by a computer to implement the method of the present invention. The recording medium may include any type of computer readable recording medium.

Although the present invention has been described in detail with reference to preferred embodiments, the present invention is not limited to the above-described embodiments, and various modifications may be made by those skilled in the art within the scope of the technical idea of the present invention. It is possible.

Claims

An overlapping information collecting unit configured to collect overlapping information between two or more Wireless Body Area Networks (WBANs) and determine an overlapping state between the two or more Wireless Body Area Networks;

A priority calculator configured to calculate priorities of the two or more wireless body area networks based on a preset traffic type priority level and a traffic volume priority level; And

A transmission section allocator for repetitively mapping and assigning colors corresponding to time slots of the wireless body area network to have different colors based on the identified overlap state;

Transmission section allocation apparatus using a distributed multi-coloring algorithm, characterized in that it comprises a.
The method of claim 1,

The overlapping information collecting unit collects 2-hop overlapping information through 2-hop message exchange between the two or more wireless body area networks, and simultaneously wirelessly exists at 1-hop and 2-hop distances according to the collected overlapping information. Transmission area allocation apparatus using a distributed multi-coloring algorithm, characterized in that the body area network is determined to be in an overlapping state.
The method of claim 1,

The traffic type priority level is a transmission interval allocation apparatus using a distributed multi-coloring algorithm, characterized in that it can be set through a weight given according to the type of data to be transmitted in the wireless body area network.
The method of claim 1,

The priority calculation unit

And calculating the priority by averaging the traffic type priority level and the traffic volume priority level of one or more sensors included in each of the two or more wireless body area networks.
The method of claim 4, wherein

The priority is

Is calculated by

Wn is a priority, m is the number of sensors included in a wireless body area network, p1 i is a traffic type priority level of an individual node, p2 i is a traffic volume priority level of an individual node Transmission section allocation device using multi-coloring algorithm.
The method of claim 1,

The transmission section allocator generates a distributed multi-coloring algorithm table by mapping the wireless body area network with a color sequence according to the randomly allocated color and the overlapping information, and generates the distributed multi-coloring algorithm table based on the generated distributed multi-coloring algorithm table. And assigning colors to the above wireless body area networks, and if the same colors are assigned to 1-hop wireless body area networks, putting one wireless body area network into a resting state based on the priority. Transmission section allocation device using multi-coloring algorithm.
The method of claim 1,

The transmission section allocator allocates the transmission section using the distributed multi-coloring algorithm, wherein the initial coloring is performed so that the colors corresponding to the time slots have different colors based on the overlapping state. Device.
Collecting overlapping information between two or more Wireless Body Area Networks (WBANs);

Calculating priorities of the at least two wireless body area networks based on a preset traffic type priority level and a traffic volume priority level;

Randomly assigning a color corresponding to the time slot to each of the two or more wireless body area networks such that the one-hop wireless body area network has different colors; And

Iteratively mapping colors corresponding to the time slots and assigning them to the wireless body area network so that the overlapping wireless body area networks have different colors;

Transmission interval allocation method using a distributed multi-coloring algorithm, characterized in that it comprises a.
The method of claim 8,

The collecting of the overlapping information may be performed by collecting two-hop overlapping information through a two-hop message exchange between the two or more wireless body area networks, and simultaneously, at one-hop and two-hop distances according to the collected overlapping information. A transmission interval allocation method using a distributed multi-coloring algorithm, wherein the existing wireless body area network is determined to be in an overlapping state.
The method of claim 8,

The traffic type priority level may be set by a weight given according to a type of data transmitted from a wireless body area network.
The method of claim 8,

The calculating of the priority may include calculating the priority by averaging the traffic type priority level and the traffic volume priority level of one or more sensors included in each of the two or more wireless body area networks. Transmission section allocation method using algorithm.
The method of claim 11,

The priority is

Is calculated by

Wn is a priority, m is the number of sensors included in a wireless body area network, p1 i is a traffic type priority level of an individual node, p2 i is a traffic volume priority level of an individual node Transmission section allocation method using multi-coloring algorithm.
The method of claim 8,

Iteratively mapping and assigning the color;

Generating a distributed multi-coloring algorithm table by mapping two or more groups according to the randomly allocated color and the overlapping information, and assigning colors to the two or more wireless body area networks based on the generated distributed multi-coloring algorithm table. And if the same color is allocated to the 1-hop wireless body area network, putting one wireless body area network into a rest state based on the priority.