KR101604984B1 - Wireless network system and channel reallocate method based on tv white space using the same - Google Patents

Wireless network system and channel reallocate method based on tv white space using the same Download PDF

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Publication number
KR101604984B1
KR101604984B1 KR1020150068101A KR20150068101A KR101604984B1 KR 101604984 B1 KR101604984 B1 KR 101604984B1 KR 1020150068101 A KR1020150068101 A KR 1020150068101A KR 20150068101 A KR20150068101 A KR 20150068101A KR 101604984 B1 KR101604984 B1 KR 101604984B1
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South Korea
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concentrator
sub
channel
pan
tvws
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KR1020150068101A
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Korean (ko)
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한정훈
김용배
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(주)누리텔레콤
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W16/00—Network planning, e.g. coverage or traffic planning tools; Network deployment, e.g. resource partitioning or cells structures
    • H04W16/02—Resource partitioning among network components, e.g. reuse partitioning
    • H04W16/04—Traffic adaptive resource partitioning
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W16/00—Network planning, e.g. coverage or traffic planning tools; Network deployment, e.g. resource partitioning or cells structures
    • H04W16/14—Spectrum sharing arrangements between different networks
    • H04W16/16—Spectrum sharing arrangements between different networks for PBS [Private Base Station] arrangements
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W84/00—Network topologies
    • H04W84/02—Hierarchically pre-organised networks, e.g. paging networks, cellular networks, WLAN [Wireless Local Area Network] or WLL [Wireless Local Loop]
    • H04W84/10—Small scale networks; Flat hierarchical networks

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Mobile Radio Communication Systems (AREA)

Abstract

The present invention relates to a wireless network system and a TVWS-based channel reallocation method using the same.
A channel reallocation method based on TVWS (TV White Space) of a wireless network system including a main PAN (Personal Area Network) and a plurality of sub PANs according to the present invention is characterized in that an upper concentrator included in the main PAN is included in the sub PAN Receiving a channel reassignment request from a subordinate concentrator; Transmitting a usable idle channel list to the sub-concentrator, receiving candidate channel information and network information to be allocated from the sub-concentrator; And reassigning the selected idle channel to the sub-concentrator according to a priority determination algorithm among the candidate channels requested from the sub-concentrator.
According to the present invention, when a self-network is constructed and used using the TVWS band, it is difficult to maintain the network due to a complicated radio environment of the channel for various reasons such as a channel allocated from a Super PAN Coordinator (SPC) When it occurs, it is possible to increase the stability of the network radio environment by reallocating a new channel according to the radio environment.

Description

TECHNICAL FIELD [0001] The present invention relates to a wireless network system and a TVWS-based channel reallocation method using the wireless network system.

More particularly, the present invention relates to a wireless network system and a TVWS-based channel reassignment method using the same, and more particularly, to a wireless network system in which when a self network network is constructed using TVWS (TV White Space) And a TVWS-based channel reallocation method using the same.

In the year 2013, analog TV broadcasting is stopped completely and converted to digital broadcasting. At the same time, TVWS (TV White Space) band of 6MHz unit which is not used for each region is generated to prevent confusion between broadcasting channels. The government's policy of using it was announced.

Here, the TVWS band includes a UHF (Ultra High Frequency) band and a VHF (very high frequency) band as frequencies allocated for TV broadcasting and does not interfere with communication of a licensed device operating in the corresponding frequency band Means the frequency band for which the license-exempt device is authorized under the conditions. That is, an available channel or a device operating as an unlicensed device in an available frequency band may be used in the frequency band in which the license apparatus is not in use. Here, the license device may be a TV, a wireless microphone, etc., and the license device may also be referred to as a licensed user, an incumbent user, or a primary user.

License-exempt devices that wish to use such TVWS bands should provide protection for licensed devices. Therefore, the license-exempt device must check whether the licenser is occupying the band to obtain available channel information before starting transmission of the signal in the TVWS band.

Also, as data communication using the 470 ~ 698MHz band becomes possible, this frequency band is superior to the 2.4GHz band, which is the existing ISM band, and is capable of communication up to 1 Km at a transmission speed of about 1 Mbps, The international standard IEEE 802.15.4m was also announced in 2014.

The IEEE 802.15.4m standard is designed to enable network expansion through a plurality of channels in one PAN (Personal Area Network) by using TVWS Multichannel Cluster Tree PAN (TMCTP).

Therefore, the independent PAN is designed to support wireless communication and power save function according to TVWS superframe while using different channels by extending to cluster PAN through one SPC (Spuer PAN Coordinator).

However, in the past, when the channel is allocated from the SPC, the wireless network can not be changed, and if the wireless environment of the channel is complicated due to various reasons such as interference with other wireless devices, maintenance of the wireless network is not stable.

The technique of the present invention is disclosed in Korean Patent Laid-Open Publication No. 10-2013-0118882 (published on Mar. 10, 2013).

It is an object of the present invention to provide a wireless network system for reallocating a channel according to a wireless environment when a self network is constructed and used using a TVWS band, And a TVWS-based channel reallocation method.

According to an aspect of the present invention, there is provided a method of channel reallocation based on TVWS, comprising: receiving a channel reallocation request from a lower concentrator included in a sub-PAN; Transmitting a usable idle channel list to the sub-concentrator, receiving candidate channel information and network information to be allocated from the sub-concentrator; And reassigning the selected idle channel to the sub-concentrator according to a priority determination algorithm among the candidate channels requested from the sub-concentrator.

In addition, the upper concentrator further includes a step of determining whether the sub-PAN including the sub-concentrator requesting the channel reallocation is a region in which the TVWS modem is installed, with reference to the previously stored geographic location database.

Also, the sub-concentrator scans the channels included in the idle channel list to acquire the candidate channel information in the order of the lowest energy level.

The network information may include at least one of a number of hops between the lower concentrator and the upper concentrator, a number of end devices connected to the lower concentrator, and a radio environment congestion of a previously allocated channel.

In addition, the priority determining algorithm may be configured such that, when a plurality of sub-concentrators are requested to allocate the same first idle channel, the number of hops, the number of end devices is large, It is possible to preferentially select a sub-concentrator having a high radio environment congestion or a low radio environment congestion when the first idle channel is used.

In addition, the idle channel of the next rank among the candidate channels received from the subordinate concentrator may be reallocated to the subordinate concentrator not reallocated to the first idle channel.

Also, a wireless network system according to an embodiment of the present invention includes a main PAN, which includes an upper concentrator and is connected to a management server through a network; And a plurality of sub-PANs including a sub-concentrator and a plurality of end devices connected to the sub-concentrator, the plurality of sub-PANs communicating with the main PAN through a pre-assigned channel, The base station transmits the available idle channel list to the subordinate concentrator, receives candidate channel information and network information to be allocated from the subordinate concentrator when the channel reallocation is requested, And may reallocate the selected idle channel to the sub-concentrator according to a prioritization algorithm.

The wireless network system and the TVWS-based channel reallocation method using the same according to the present invention can be applied to various types of wireless networks such as a wireless network, which is allocated from a Super PAN Coordinator (SPC) If the wireless environment of the channel is complicated and the network is difficult to maintain, it is possible to increase the stability of the network wireless environment by reallocating a new channel according to the wireless environment.

In addition, the present invention can support a wireless communication and a power saving function in accordance with a TVWS superframe while an independent PAN (Personal Area Network) is extended to a cluster PAN through one SPC to use different channels.

1 is a system configuration diagram illustrating a wireless network system according to an embodiment of the present invention.
2 is a flowchart illustrating a TVWS-based channel reallocation method in a wireless network system according to an embodiment of the present invention.
FIG. 3 is a flowchart illustrating the prioritization algorithm shown in step S260 of FIG.

Hereinafter, a wireless network system according to an embodiment of the present invention and a TVWS-based channel reallocation method using the same will be described with reference to the accompanying drawings. In this process, the thicknesses of the lines and the sizes of the components shown in the drawings may be exaggerated for clarity and convenience of explanation.

Further, the terms described below are defined in consideration of the functions of the present invention, which may vary depending on the intention or custom of the user, the operator. Therefore, definitions of these terms should be made based on the contents throughout this specification.

First, a wireless network system according to an embodiment of the present invention will be described.

1 is a system configuration diagram illustrating a wireless network system according to an embodiment of the present invention.

1, a wireless network system 100 according to an exemplary embodiment of the present invention includes a main PAN 110 and a sub-PAN 120. As shown in FIG.

More specifically, the wireless network system 100 uses a TVWS Multichannel Cluster Tree PAN (TMCTP) to transmit a plurality of sub-PANs 120 through a plurality of channels from a single main (Personal Area Network) It is designed to be scalable.

The main PAN 110 and the plurality of sub PANs 120 have unique IDs and are designed to support wireless communication and power save functions in accordance with TVWS (TV White Space) superframe while using different channels do.

The main PAN 100 according to the embodiment of the present invention includes a super PAN coordinator 111 and a plurality of end devices D connected to the super concentrator 111, And is connected to the server 130.

At this time, the super concentrator 111 may obtain a geolocation database from a geolocation database server (not shown), wherein the geolocation database is a list of available idle channels in the geographical location of the super concentrator 111, The super concentrator 111 selects any one of the idle channels available in the region where the TVWS wireless modem is installed using the acquired geo-location database and transmits the selected idle channel and non-beacon slot to the sub-concentrator 121 .

The sub-PAN 120 also includes a lower concentrator 121 extended from the upper concentrator 111 and a plurality of end devices D connected to the lower concentrator 121, And performs communication with the main PAN 110.

At this time, the lower concentrator 121 may request channel reassignment to the higher concentrator 111 according to the radio environment congestion of the pre-allocated channel. If the radio environment congestion is higher than the reference value, mutual interference of various radio devices, It is determined that the wireless environment is deteriorated due to the influence of the channel condition,

Accordingly, when the channel concentrator 111 receives a channel reallocation request from the lower concentrator 121, the upper concentrator 111 receives the channel reallocation request from the sub-concentrator 121, 120 is in the area where the TVWS modem is installed. If it is determined that the area is the area where the TVWS modem is installed, the subordinate concentrator 121 delivers the available idle channel list.

At this time, the lower concentrator 121 receives the idle channel list from the upper concentrator 111, scans the channels included in the idle channel list, and outputs a plurality of candidate channel information in order of decreasing energy level .

Here, the energy level can be measured using an energy detection method. Since it is determined that the radio environment congestion is lower (radio environment is better) as the measured energy level value is lower, a plurality To obtain candidate channel information.

The candidate channel information thus obtained includes the number of hops between the lower concentrator 121 and the higher concentrator 111, the number of end devices connected to the lower concentrator 121, the radio environment congestion To the upper concentrator 111 together with the network information including the network information.

Accordingly, the super concentrator 111 receives the candidate channel information and the network information to be allocated from the sub-concentrator 121, selects the idle channel selected according to the priority determination algorithm among the candidate channels requested from the sub-concentrator 121, To the sub-concentrator (121).

In this case, the priority determining algorithm basically selects the idle channel of the first rank among the requested channel information requested from the sub-concentrator 121, and if the same first idle channel is allocated from the plurality of sub-concentrators 121 If the request is received, the number of hops, the number of end devices D, the radio environment congestion of the pre-allocated channel is high, or the radio environment congestion is low when the first idle channel is used. (121) is preferentially selected.

More specifically, when a plurality of sub-concentrators 121 are requested to allocate the same first idle channel, the super concentrator 111 selects one of the plurality of sub-concentrators 121, The lower concentrator 121 having a larger number of hops between the lower concentrators 121 and 111 is preferentially selected and when the number of hops is the same, And if the number of end devices D is the same, the lower concentrator 121 having a high radio environment congestion of the pre-allocated channel is preferentially selected. If the radio environment congestion of the pre-allocated channel is the same, The sub concentrator 121 having the lowest radio environment congestion degree when the rank idle channel is used is preferentially selected.

1, if the sub-concentrator 121 of the sub-PAN 120 ID 2 and the sub-concentrator 121 of the sub-PAN 120 ID 5 are connected to the upper concentrator 111 at the same time The hop count of the sub PAN 120 ID 2 is 1 and the hop count of the sub PAN 120 ID 5 is 2. Therefore, The channel 121 is preferentially reallocated.

Alternatively, when the sub-concentrator 121 of the sub-PAN 120 ID 2 having the same hop count and the sub-concentrator 121 of the sub-PAN 120 ID 3 simultaneously request reallocation of the same channel, The channel is preferentially reallocated to the sub-concentrator 121 of the sub-PAN 120 ID 2 having a large number of end devices D connected to the device 121.

The upper concentrator 111 compares the sequentially ranked idle channels with each other in such a manner that the lower concentrator 121 notifies the subordinate concentrator 121 that the first idle channel is not reallocated, Reallocate the channel.

Hereinafter, a channel reallocation method based on TVWS (TV White Space) of a wireless network system including a main PAN (Personal Area Network) and a plurality of sub-PANs according to an embodiment of the present invention will be described.

FIG. 2 is a flowchart illustrating a TVWS-based channel reassignment method in a wireless network system according to an embodiment of the present invention. FIG. 3 is a flowchart for explaining a priority determination algorithm shown in step S260 of FIG. The specific operation of the present invention will be described.

Before describing the specific operation of the present invention, the upper concentrator 111 included in the main PAN 110 uses the geographical location database obtained from the geographical location database server to determine the idle channel available in the area where the TVWS wireless modem is installed And allocates the selected idle channel and non-beacon slot to the sub-concentrator 121 included in the sub-PAN 120. The sub- Accordingly, when the sub-PAN 120 is in communication with the main PAN 110 through a predetermined channel, and the radio environment is deteriorated due to mutual interference of various radio devices and other repeaters, A method for reallocating a channel to the lower concentrator 121 is as follows.

2, the upper concentrator 111 receives a channel reallocation request from the lower concentrator 121 (S210).

At this time, the upper concentrator 111 determines whether the sub-PAN 120 including the sub-concentrator 121 requesting the channel reallocation is the area where the TVWS modem is installed (S220) When it is determined that the modem is installed, the idle channel list is transmitted to the sub-concentrator 121 (S230).

Next, the sub-concentrator 121 scans the channels included in the idle channel list transmitted in step S230, and obtains candidate channel information in order of decreasing energy level (S240), and transmits the obtained candidate channel information to the network information To the upper concentrator 111 (S250).

Here, the energy level can be measured using an energy detection method. Since it is determined that the radio environment congestion is lower (radio environment is better) as the measured energy level value is lower, a plurality To obtain candidate channel information.

The candidate channel information thus obtained includes the number of hops between the lower concentrator 121 and the upper concentrator 111, the number of end devices connected to the lower concentrator 121, And delivers it to the super concentrator 111 together with the network information including the congestion degree.

Accordingly, the super concentrator 111 receives the candidate channel information and the network information to be allocated from the sub-concentrator 121 and selects the idle channel according to a priority determination algorithm among the candidate channels requested from the sub- (S260), and reassigns the selected idle channel to the sub-concentrator 121 (S270).

In this case, the priority determining algorithm basically selects the idle channel of the first rank among the requested channel information requested from the sub-concentrator 121, and if the same first idle channel is allocated from the plurality of sub-concentrators 121 If the request is received, the number of hops, the number of end devices D, the radio environment congestion of the pre-allocated channel is high, or the radio environment congestion is low when the first idle channel is used. (121) is preferentially selected.

Referring to FIG. 3, in step S260, when the plurality of subordinate concentrators 121 are requested to allocate the same first idle channel in step S261, the superordinate concentrator 111 includes a plurality of subordinate concentrators 121 The number of hops between the lower concentrator 121 and the upper concentrator 111 is compared with the number of hops between the lower concentrator 121 and the upper concentrator 111 in step S262.

However, if it is determined in step S262 that the number of hops is the same, the number of end devices D connected to the lower concentrator 121 is compared (S264), and the lower concentrator 121 having a larger number of end devices D is preferentially selected (S265).

If the number of end devices D is equal to the number of end devices D in step S264, the radio environment congestion degree of the pre-allocated channel is compared (S266), and the sub-concentrator 121 having high radio environment congestion of the pre- (S267).

However, if it is determined in step S266 that the radio environment congestion of the allocated channel is the same, the sub-concentrator 121 having the lowest radio environment congestion level when the first idle channel is used is selected (S268) .

In this manner, the sub-PAN 120 is reassigned to the sub-PAN 120, which is determined in order of priority, and the sub-PAN 120, which has not been determined, The channel is reassigned from the main PAN 110.

As described above, in the wireless network system according to the embodiment of the present invention and the TVWS-based channel reallocation method using the TVWS band, when a self network is constructed and used, a channel allocated from a super PAN coordinator (SPC) If the wireless environment of the channel is complicated due to various reasons such as the interference of the other wireless devices and the network is difficult to maintain, the stability of the network wireless environment can be increased by reallocating a new channel according to the wireless environment.

In addition, an independent PAN (Personal Area Network) can be extended to a cluster PAN via a single SPC to support wireless communication and power save functions for the TVWS superframe while using different channels.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the scope of the invention as defined by the appended claims. will be. Accordingly, the true scope of the present invention should be determined by the following claims.

110: Main PAN 111: Upper concentrator
120: Sub-PAN 121: Sub-concentrator
130: management server 140: network
D: End device

Claims (12)

A channel reallocation method based on TVWS (TV White Space) of a wireless network system including a main PAN (Personal Area Network) and a plurality of sub PANs,
Receiving an upper layer concentrator included in the main PAN from a lower concentrator included in the sub PAN;
Determining whether the sub-PAN including the sub-concentrator requesting the channel reallocation is an area in which the TVWS modem is installed, by referring to the geographical location database stored in advance;
Transmitting the available idle channel list to the lower concentrator and receiving candidate channel information and network information to be allocated from the lower concentrator if it is determined that the TVWS modem is installed; And
And reassigning the selected idle channel to the sub-concentrator according to a priority determination algorithm among the candidate channels requested from the sub-concentrator. delete The method according to claim 1,
Wherein the sub-concentrator scans each of the channels included in the idle channel list to obtain the candidate channel information in order of decreasing energy level. The method according to claim 1,
The network information includes:
A number of end devices connected to the sub-concentrator, and a radio environment congestion of a pre-allocated channel, the number of hops between the sub-concentrator and the super-concentrator, the number of end devices connected to the sub- 5. The method of claim 4,
Wherein the prioritization algorithm comprises:
When the number of hops is high, the number of end devices is large, the wireless environment congestion of the pre-allocated channel is high, A TVWS-based channel reallocation method for preferentially selecting a lower concentrator having a lower radio environment congestion when a rank idle channel is used. 6. The method of claim 5,
And reassigning the idle channel of the next rank among the candidate channels received from the subordinate concentrator to the subordinate concentrator not reallocated with the first idle channel. A main PAN including an upper concentrator and connected to a management server through a network; And
A sub-concentrator and a plurality of end devices connected to the sub-concentrator, the plurality of sub-PANs communicating with the main PAN through a pre-allocated channel,
Wherein the upper concentrator comprises:
When the sub-centralizer requests the channel reallocation, it is determined whether the sub-PAN including the sub-concentrator requesting channel reassignment by referring to the pre-stored geographic location database is the area where the TVWS modem is installed, And transmits the available idle channel list to the sub-concentrator, receives candidate channel information and network information to be allocated from the sub-concentrator, and selects a priority determination algorithm among the candidate channels requested from the sub- And reassigns the selected idle channel to the sub-concentrator according to the selected idle channel. delete 8. The method of claim 7,
The sub-
And scans the channels included in the idle channel list to acquire the candidate channel information in order of decreasing energy level. 8. The method of claim 7,
The network information includes:
A number of end devices connected to the sub-concentrator, and a radio environment congestion of a pre-allocated channel, the number of hops between the sub-concentrator and the super-concentrator. 11. The method of claim 10,
Wherein the prioritization algorithm comprises:
When the number of hops is high, the number of end devices is large, the wireless environment congestion of the pre-allocated channel is high, And a lower concentrator having a lower radio environment congestion degree when the rank idle channel is used is preferentially selected. 12. The method of claim 11,
And reassigns the idle channel of the next rank among the candidate channels received from the subordinate concentrator to the subordinate concentrator not reallocated to the first idle channel.
KR1020150068101A 2015-05-15 2015-05-15 Wireless network system and channel reallocate method based on tv white space using the same KR101604984B1 (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR102351439B1 (en) * 2020-09-01 2022-01-17 (주)비에스테크놀로지 TVWS auto pairing system and method
KR20230143685A (en) * 2022-04-06 2023-10-13 이노넷 주식회사 Wireless backhaul system using tvws for indoor and underground tunnels where gps reception is not avaiable

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR102351439B1 (en) * 2020-09-01 2022-01-17 (주)비에스테크놀로지 TVWS auto pairing system and method
KR20230143685A (en) * 2022-04-06 2023-10-13 이노넷 주식회사 Wireless backhaul system using tvws for indoor and underground tunnels where gps reception is not avaiable
KR102598037B1 (en) 2022-04-06 2023-11-03 이노넷 주식회사 Wireless backhaul system using tvws for indoor and underground tunnels where gps reception is not avaiable

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