KR20170092008A

KR20170092008A - Efficient subchannelization Method for partial band jamming avoidance and System for the same

Info

Publication number: KR20170092008A
Application number: KR1020160013002A
Authority: KR
Inventors: 이재생; 김용신; 최형석; 송유찬; 김진영; 신요안
Original assignee: 국방과학연구소
Priority date: 2016-02-02
Filing date: 2016-02-02
Publication date: 2017-08-10
Also published as: KR101770912B1

Abstract

The present invention relates to a jamming processing technique, and more particularly, to a method and system for implementing an effective jamming response algorithm through subchannelization in case of partial band jamming.
According to the present invention, system performance is improved by maximizing the use of all available channels except adjacent channels exposed to a jamming attack when a partial jamming attack occurs in an active unattended battle system.

Description

[0001] The present invention relates to a partial band jamming avoiding method and an apparatus therefor, and more particularly to an efficient partial band jamming avoiding method and a system thereof,

The present invention relates to a jamming processing technique, and more particularly, to a method and system for implementing an effective jamming response algorithm through subchannelization in case of partial band jamming.

Jamming is an electronic jamming that is a classic electronic attack. This is done in the form of a deception that causes disturbance or false information to be rejected to use a specific frequency or radio wave by radiating radio frequency (RF) energy.

There is a dynamic frequency selection (DFS) technique in which a terminal as a negative user of a specific frequency band can jump to another channel while avoiding frequency interference such as radar, satellite, or jamming. The operation of the DFS has a disadvantage that it takes a certain time to respond to the jammer by the full DFS test period in which a new channel is searched in the event of a jamming attack, and communication is interrupted during that time.

This is because after the execution time of the full DFS test, a new channel is selected by the access point (AP) and another terminal may take additional time to recognize the new channel of the AP.

In particular, such jamming is an act of confusing or obstructing the communication system of the other party, and there are various kinds according to attack methods such as broadband jamming, partial band jamming, tone jamming, Gaussian jamming, narrow band jamming and / or attack target. In addition, a jammer with limited average power generates a jamming signal intensively in a limited partial frequency band, and a more effective method is required.

1. Korean Patent Publication No. 10-2002-0062001

1. Hyung-geun Lee, "A Study on Performance of Frequency Hopping System Using FFT in Partial-Band Jamming Environment" Yonsei University, 2001

An object of the present invention is to provide an efficient partial band jamming avoidance method and a system therefor, which are capable of implementing an effective corresponding algorithm for partial band jamming, .

The present invention provides an efficient partial-band jamming avoidance method through subchannelization that can implement an effective countermeasure algorithm for partial-band jamming in order to achieve the above-described problems.

A partial band jamming avoiding method in a base station includes:

(a) transmitting a channel information to a mobile station by a base station;

(b) normal operation of the base station as the mobile station allocates the channel information;

(c) checking whether the base station has a jamming attack during the normal operation;

(d) if the jamming attack is detected as a result of the checking, the base station increases the number of subchannels in the channel according to the channel information to form the subchannel;

(e) performing a channel search for the jamming attack for each of the plurality of subchannels by the base station; And

(f) selecting the available channels excluding the subchannels receiving the jamming attack among the plurality of subchannels, and transmitting the channel information to the mobile terminal by the base station according to the measurement result, thereby performing spectacular communication .

Meanwhile, in the partial band jamming avoiding method in the mobile terminal,

(a) receiving a channel information from a base station by a mobile terminal;

(b) performing normal operation by allocating the channel information to the mobile station;

(c) checking whether the mobile station has lost a jamming attack or the base station during the normal operation;

(d) if the jamming attack or the loss of the base station is detected as a result of checking, forming a plurality of subchannels in the channel according to the channel information to increase;

(e) performing a channel search for checking whether the mobile terminal has a jamming attack on each of the plurality of sub-channels or a communication quality deterioration due to the loss of the base station; And

and (f) selecting the available channels excluding the subchannels receiving the jamming attack among the plurality of subchannels by the mobile terminal according to the measurement result, thereby performing spectacular communication.

In this case, the channel search is performed for each sub-channel through a beacon, and the mobile station stops data transmission during the channel search.

In addition, the channel search may be performed by measuring the state of all subchannels including a subchannel having a jamming attack through a beacon.

The base station and the mobile terminal may operate according to IEEE 802.16 WiMAX (Worldwide Interoperability for Microwave Access) standard protocol.

In addition, in the step (b), the base station and the mobile terminal exchange data with each other using full channels.

In addition, the jamming attack may be a partial-band jamming attack.

On the other hand, another embodiment of the present invention is an efficient partial band jamming avoiding system through subchannelization comprising a mobile terminal and a base station, the base station including: a first communication unit for transmitting channel information to the mobile terminal; The mobile terminal checks whether a jamming attack exists during a normal operation according to the allocation of the channel information, and if the jamming attack is detected, A jamming detection unit; And performing channel searching for a jamming attack on each of the plurality of subchannels, selecting an available channel excluding subchannels receiving a jamming attack among the plurality of subchannels according to a measurement result, And a first measurement unit for performing spectacular communication by transmitting the channel information to the mobile station through the second communication unit, wherein the mobile station comprises: a second communication unit for receiving channel information from the base station; If the jamming attack or the loss of the base station is detected as a result of checking, it is determined whether there is a jamming attack or loss of the base station during normal operation by allocating the channel information, and if a jamming attack or loss of the base station is detected, A second jamming detection unit for generating a second jamming signal; And performing a channel search for confirming a decrease in communication quality due to a jamming attack or a loss of a BS in each of the plurality of subchannels, And a second measurement unit for performing spectacular communication by selecting the sub-channelization sub-channel. The present invention can provide an efficient partial band jamming avoidance system through sub-channelization.

According to the present invention, when a partial jamming attack occurs in an unmanned combat system operating according to the IEEE 802.16 WiMAX (Worldwide Interoperability for Microwave Access) standard protocol, by maximally using all available channels except adjacent channels exposed to a jamming attack, Improve performance.

Another advantage of the present invention is that an algorithm with a higher efficiency of frequency use can be provided as the number of subchannels increases.

1 is a conceptual diagram of a general partial band jamming model.
2 is a diagram showing a general partial band when a partial band jamming attack occurs.
3 is a conceptual diagram illustrating an increase in frequency band efficiency according to an increase in the number of jamming channels through subchannelization when a partial band jamming attack occurs according to an embodiment of the present invention.
FIG. 4 is a flowchart illustrating a process performed by a base station to implement efficient partial-band jamming avoidance through subchannelization according to an embodiment of the present invention.
5 is a flowchart illustrating a process performed by a mobile terminal to implement efficient partial band jamming avoidance through subchannelization according to an embodiment of the present invention.
FIG. 6 is a system for implementing efficient partial band jamming avoidance through channelization according to an embodiment of the present invention.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It is to be understood, however, that the invention is not to be limited to the specific embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

Like reference numerals are used for similar elements in describing each drawing.

The terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another.

For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component. The term "and / or" includes any combination of a plurality of related listed items or any of a plurality of related listed items.

Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the contextual meaning of the related art and are to be interpreted as either ideal or overly formal in the sense of the present application Should not.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an efficient partial band jam avoidance method and a system thereof according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a conceptual diagram of a general partial band jamming model. Particularly, FIG. 1 shows a jamming model in the case where background noise and partial band jamming exist at the same time. Referring to FIG. 1, when there are five subchannels Ch1 to Ch5, when the third channel Ch3 is the currently used channel, the second channel Ch2, the fourth channel Ch4, The available channels available for receiving the jamming attack 110 are channel 1 (Ch 1) and channel 5 (Ch 5).

In this case, the power density function of the jamming signal is as follows.

here,

Is the power spectral density function of additive white Gaussian noise (AWGN) and the power density function of the intentional jamming signal is

. Also,

Is the entire frequency band,

A jamming frequency band,

Jamming signal power,

Is a power density function of the jamming signal,

Represents the band occupancy rate of the jamming signal.

2 is a diagram showing a general partial band when a partial band jamming attack occurs. Referring to FIG. 2, only the first channel (Ch1) and the fifth channel (Ch5) are usable as described above in FIG.

3 is a conceptual diagram illustrating an increase in frequency band efficiency due to an increase in the number of jamming channels through subchannelization when a partial band jamming attack occurs according to an embodiment of the present invention. Fig. 8 is a conceptual diagram showing an increase in frequency band efficiency with an increase in the number of jamming channels. 3, when the number of subchannels is 10 (Ch1 to Ch10), available usable channels that are not affected by partial band jamming are channel 1 (Ch1), channel 2 (Ch2), channel 3 It is possible to use a wider frequency band than when the number of subchannels is five for channel (Ch3), channel (Ch8), channel (Ch9) and channel (Ch10) .

FIG. 4 is a flowchart illustrating a process performed by a base station (BS) to implement efficient partial band jamming avoidance through subchannelization according to an embodiment of the present invention. Referring to FIG. 4, an initial operation of a base station uses all channels allocated to a base station and a mobile terminal (for example, an unmanned robot) (steps S410 and S420).

The base station transmits a beacon having information on the channel to the mobile station and operates normally to transmit and receive data (steps S430 and S440).

During this normal operation, it is confirmed whether there is a jamming attack (step S450).

If the jamming attack is detected in step S450, the subchannels for the 20 MHz channel allocated to the base station and the mobile station in the frequency band of 900 MHz to 920 MHz are formed for detection and / or avoidance of the partial jamming, (Step S460).

Through the channel search, the presence or absence of an influence on the jamming attack of each subchannel is checked to secure an available channel (step S470). In addition, after selecting a usable channel except for a subchannel receiving a jamming attack, the selected available channel information is transmitted to the mobile terminal so that normal communication is established between the base station and the mobile terminal.

A channel search is a measurement for each channel through a beacon. During this channel search, all mobile stations stop transmitting data. Also, through the beacon, the current jamming attack measures the state of the entire subchannel including the received subchannel.

FIG. 5 is a flowchart illustrating a process performed by a mobile station (UE) to implement efficient partial band jamming avoidance through subchannelization according to an embodiment of the present invention. Referring to FIG. 5, the UE receives the channel information allocated by the BS through a beacon and performs a normal operation using the allocated channel (steps S510 and S520).

During this normal operation, the mobile terminal checks whether a jamming attack has occurred (step S540).

If it is determined in step S540 that the jamming attack is not detected, it is determined whether the base station is lost (step S541).

If the base station is not lost in step S541, the process proceeds to step S530. If the base station is lost, the process proceeds to step S550. Loss of a base station (BS) refers to a state in which when a direct jamming attack is applied to a base station, the terminal can not transmit / receive information smoothly due to quality degradation such as voice and image data.

In step S540, if a jamming attack is detected as a result of the check in step S540, a subchannel is formed for detection and / or avoidance of partial jamming, and each subchannel search is performed (step S550). Channel detection and channel search are performed when jamming attack detection or communication quality degradation problem occurs.

Channel search refers to the process of selecting the best channel among all the channels in addition to the channel used when the communication quality deteriorates due to maliciousness, spontaneous generation due to jamming, or the number of users exceeding the capacity of one channel. The subchannel generation and / or jamming avoidance algorithm proposed in one embodiment of the present invention is different from the frequency hopping technique of the existing jamming avoidance method by forming a subchannel according to the partial band jamming parameter to secure the maximum available channel .

Through the channel search, the presence or absence of an influence on the jamming attack of each subchannel is checked to secure an available channel (step S470).

FIG. 6 is a system for implementing efficient partial band jamming avoidance through channelization according to an embodiment of the present invention. Referring to FIG. 6, the partial band jamming avoiding system includes a base station 610 and a mobile terminal 620.

The base station 610 includes a first communication unit 611 for transmitting channel information to the mobile terminal 620 and a second communication unit 610 for checking whether there is a jamming attack during normal operation according to the allocation of the channel information by the mobile terminal 620, A first jamming detection unit 612 for detecting a jamming attack by forming a plurality of subchannels in a channel according to the channel information, a channel search is performed for each of the plurality of subchannels, Selects an available channel excluding subchannels undergoing a jamming attack among the plurality of subchannels according to the measurement result, and transmits the channel information to the mobile terminal 620 through the first communication unit 611 to perform a prominent communication A first measuring unit 613, and the like.

The mobile terminal 620 includes a second communication unit 621 for receiving channel information from the base station 610 and a second communication unit 621 for allocating the channel information to check whether there is a jamming attack or a loss of the base station during normal operation, A second jamming detection unit 622 for detecting a jamming attack or loss of a base station and forming a plurality of subchannels in a channel according to the channel information to generate a jamming attack, A second measurement unit 623 for performing channel searching for confirming a decrease in communication quality according to a measurement result, selecting a usable channel excluding subchannels receiving a jamming attack among the plurality of subchannels, And the like.

The term "part" and the like described in Fig. 6 means a unit for processing at least one function or operation, which can be implemented by a combination of hardware and / or software.

610:
611: first communication unit 612: first jamming detection unit
613: first measuring unit
620:
621:
622: second jamming detection unit 623: second measurement unit

Claims

(a) transmitting a channel information to a mobile station by a base station;
(b) normal operation of the base station as the mobile station allocates the channel information;
(c) checking whether the base station has a jamming attack during the normal operation;
(d) if the jamming attack is detected as a result of the checking, the base station increases the number of subchannels in the channel according to the channel information to form the subchannel;
(e) performing a channel search for the jamming attack for each of the plurality of subchannels by the base station; And
(f) selecting the available channels excluding the subchannels receiving the jamming attack from among the plurality of subchannels, and transmitting the channel information to the mobile terminal in accordance with the measurement result, thereby performing spectacular communication;
Wherein the partial band jamming avoidance method comprises the steps of:

(a) receiving a channel information from a base station by a mobile terminal;
(b) performing normal operation by allocating the channel information to the mobile station;
(c) checking whether the mobile station has lost a jamming attack or the base station during the normal operation;
(d) if the jamming attack or the loss of the base station is detected as a result of checking, forming a plurality of subchannels in the channel according to the channel information to increase;
(e) performing a channel search for checking whether the mobile terminal has a jamming attack on each of the plurality of sub-channels or a communication quality deterioration due to the loss of the base station; And
(f) selecting the available channels excluding the subchannels receiving the jamming attack among the plurality of subchannels, and performing spectacular communication according to the measurement result;
Wherein the partial band jamming avoidance method comprises the steps of:

3. The method according to claim 1 or 2,
Wherein the channel search is performed for each subchannel through a beacon, and the mobile station stops data transmission during the channel search.

3. The method according to claim 1 or 2,
Wherein the channel search measures a state of all subchannels including a subchannel that has been subjected to a jamming attack through a beacon.

3. The method according to claim 1 or 2,
Wherein the base station and the mobile terminal operate according to IEEE 802.16 Worldwide Interoperability for Microwave Access (WiMAX) standard protocol.

The method according to claim 1,
Wherein, in step (b), the base station and the mobile terminal exchange data with each other using full channels.

3. The method according to claim 1 or 2,
Wherein the jamming attack is a partial-band jamming attack.

An efficient partial band jamming avoidance system by subchannelization comprising a mobile terminal and a base station,
Wherein the base station comprises: a first communication unit for transmitting channel information to the mobile station; The mobile terminal checks whether a jamming attack exists during a normal operation according to the allocation of the channel information, and if the jamming attack is detected, A jamming detection unit; And performing channel searching for a jamming attack on each of the plurality of subchannels, selecting an available channel excluding subchannels receiving a jamming attack among the plurality of subchannels according to a measurement result, And a first measurement unit for transmitting the received signal to the mobile terminal through the base station,
The mobile terminal includes: a second communication unit for receiving channel information from the base station; If the jamming attack or the loss of the base station is detected as a result of checking, it is determined whether there is a jamming attack or loss of the base station during normal operation by allocating the channel information, and if a jamming attack or loss of the base station is detected, A second jamming detection unit for generating a second jamming signal; And performing a channel search for confirming a decrease in communication quality due to a jamming attack for each of the plurality of subchannels or loss of a base station and for determining an available channel excluding subchannels receiving a jamming attack among the plurality of subchannels And a second measurement unit for performing spectacular communication by selecting the partial banding jamming avoidance system.