KR101760084B1 - Apparatus and method of molecular communications, and recording medium thereof - Google Patents

Abstract

A molecular communication method, a molecular communication apparatus, and a recording medium. A method for molecular communication according to an embodiment of the present invention is a molecular communication method for transmitting data between nodes whose distance is changed by molecular communication, the method comprising: controlling a symbol interval in which symbols are transmitted between nodes according to distances between nodes; ; ≪ / RTI > According to the embodiment of the present invention, the data transmission amount of the molecular communication channel can be maximized based on the distance between the nodes.

Description

[0001] Molecular communication methods, molecular communication devices, and recording media [0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molecular communication method, a molecular communication apparatus, and a recording medium. More particularly, the present invention relates to a molecular communication method, a molecular communication apparatus and a recording medium in which a symbol interval is variable based on a distance between nodes.

Recently, interest in molecular communications is increasing. In general, the transmission of information through the emission of molecules at the transmitter, the diffusion of molecules through the medium, and the reception of information through the detection / absorption of molecules using receptors at the receiver The communication method through the step-by-step process is called molecular communication. Molecular communication is a proposed communication method for communication between biological / biomechanical devices, which can be applied in the environment where the existing wired / wireless communication technology is difficult to apply, or between a device of a few hundreds of nanometers or a body. Recent developments in bioscience and nanoscience have led to the development and use of very small-sized or nanometer-sized devices for various purposes that operate in the body. A variety of body monitoring, target drug delivery systems, and bio-hybrid replacement organs are typical applications of these nanotechnologies. To achieve these goals, Communication between devices is essential. However, the nanometer devices in the body are difficult to apply the existing wireless communication technology due to the restriction of the size and the limitation of the available energy source, and molecular communication through emission and detection of molecules is the most attention now.

Several modulation schemes for molecular communications have been proposed. First, there is a CSK (Concentration Shift Keying) method in which information is encoded by the number of molecules to be emitted at a specific time on the sender side. When the CSK is used, the receiver side determines and decodes information transmitted based on the number of specific molecules detected / received within a limited time. MoSK (Molecule Shift Keying), which expresses different information in different molecules, and PPM (Pulse Position Modulation), which encodes information at the time of molecular emission. In the existing communication method, a transmission / reception signal / symbol interval is determined during transmission of a transmission unit (packet).

The present invention provides a molecular communication method, a molecular communication apparatus, and a recording medium in which a symbol interval is variable based on a distance between nodes.

The present invention also provides a molecular communication method, a molecular communication apparatus, and a recording medium capable of maximizing a data transmission amount of a molecular communication channel based on a distance between nodes.

The problems to be solved by the present invention are not limited to the above-mentioned problems. Other technical subjects not mentioned will be apparent to those skilled in the art from the description below.

A molecular communication method according to an aspect of the present invention is a molecular communication method for transmitting data by molecular communication between nodes whose distance is changed, characterized in that a symbol interval in which symbols are transmitted between the nodes according to a distance between the nodes ;

Wherein adjusting the symbol interval comprises: reducing the symbol interval if the distance between the nodes decreases; And increasing the symbol interval if the distance between the nodes increases.

Wherein adjusting the symbol interval comprises: emitting a molecular signal serving as a message for a first node of the nodes requesting data transmission; The second node of the nodes detecting the molecular signal for a predetermined time; Estimating a distance between the first node and the second node based on a local maximum value of the number of molecules detected during the predetermined time at the second node; Setting the symbol interval to be used for data transmission from the second node to the first node based on the distance between the first node and the second node; And transmitting data from the second node to the first node according to the symbol interval.

The step of predicting the distance between the first node and the second node may predict a distance between the first node and the second node according to Equation (1).

[Equation 1]

r (k) =

(K) represents a local maximum value of the number of molecules, and Q represents a local maximum value of the number of molecules emitted by the first node, and k represents a distance between the first node and the second node. Represents the number of molecular signals, and a is a predetermined constant.

The step of setting the symbol interval may set the symbol interval according to Equation (2).

[Equation 2]

tx (n) = b * r (x) ² + c * r (x) + d

Where b, c, and d are constants that are set in advance, respectively, and tx (n) represents the symbol interval, r (x) represents a distance between the first node and the second node, to be.

The step of transmitting data to the first node may transmit data to the first node using CSK (Concentration Shift Keying) molecular communication at intervals of tx (n).

According to another aspect of the present invention, there is provided a computer-readable recording medium on which a program for executing the molecular communication method is recorded.

According to another aspect of the present invention there is provided a molecular communication apparatus for transmitting data by way of molecular communication between nodes whose distance is changing, comprising: means for adjusting a symbol interval at which a symbol is transmitted between the nodes according to a distance between the nodes A symbol interval adjusting unit; And a transmitter for transmitting data to a first one of the nodes according to the symbol interval.

The molecular communication apparatus comprising: a detector for detecting a molecular signal serving as a message requesting data transmission from the first node; And a distance predicting unit for predicting a distance from the first node based on a local maximum value of the number of molecules detected for a predetermined time.

The symbol interval adjuster may decrease the symbol interval when the distance between the nodes decreases, and increase the symbol interval when the distance between the nodes increases.

The distance predicting unit may predict the distance to the first node according to Equation (1).

The symbol interval adjuster may set the symbol interval according to Equation (2).

The transmitting unit may transmit data to the first node using CSK (Concentration Shift Keying) molecular communication at intervals of tx (n).

According to an embodiment of the present invention, there is provided a molecular communication method, a molecular communication apparatus, and a recording medium in which a symbol interval is variable based on a distance between nodes.

According to an embodiment of the present invention, there is provided a molecular communication method, a molecular communication device, and a recording medium capable of maximizing data transfer amount of a molecular communication channel based on a distance between nodes.

The effects of the present invention are not limited to the effects described above. Unless stated, the effects will be apparent to those skilled in the art from the description and the accompanying drawings.

1 is a block diagram of a molecular communication system according to an embodiment of the present invention.
2 is a configuration diagram of a molecular communication apparatus according to an embodiment of the present invention.
3 is a flowchart of a molecular communication method according to an embodiment of the present invention.

Other advantages and features of the present invention and methods for accomplishing the same will be apparent from the following detailed description of embodiments thereof taken in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, and the present invention is only defined by the scope of the claims. Although not defined, all terms (including technical or scientific terms) used herein have the same meaning as commonly accepted by the generic art in the prior art to which this invention belongs. A general description of known configurations may be omitted so as not to obscure the gist of the present invention. In the drawings of the present invention, the same reference numerals are used as many as possible for the same or corresponding configurations. To facilitate understanding of the present invention, some configurations in the figures may be shown somewhat exaggerated or reduced.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the terms "comprises", "having", or "having" are intended to specify the presence of stated features, integers, steps, operations, components, Steps, operations, elements, parts, or combinations thereof, whether or not explicitly described or implied by the accompanying claims.

Used throughout this specification may refer to a hardware component such as, for example, software, FPGA or ASIC, as a unit for processing at least one function or operation. However, "to" is not meant to be limited to software or hardware. &Quot; to " may be configured to reside on an addressable storage medium and may be configured to play one or more processors.

As an example, the term '~' includes components such as software components, object-oriented software components, class components and task components, and processes, functions, attributes, procedures, Routines, segments of program code, drivers, firmware, microcode, circuitry, data, databases, data structures, tables, arrays, and variables. The functions provided by the components and components may be performed separately by a plurality of components and components, or may be integrated with other additional components.

A molecular communication method according to an embodiment of the present invention is a molecular communication method for transmitting data by molecular communication between nodes whose distance is changing, wherein a symbol interval (signal interval) at which symbols are transmitted between nodes is a distance As shown in FIG.

In the conventional communication method, a transmission / reception signal / symbol interval is determined during transmission of a certain transmission unit (packet). In the molecular channel, when the distance between two nodes that transmit and receive is changed during communication, the symbol interval is changed according to the distance between two nodes transmitting and receiving every symbol. The amount of the molecular channel can be increased.

In one embodiment, when two moving nodes perform molecular communication using a CSK (Concentration Shift Keying) modulation scheme, the amount of transmission of a molecular communication channel can be increased by using a variable signal interval during packet transmission.

For example, if the distance between two communicating nodes is reduced, the signal interval is decreased during packet transmission to increase the channel throughput, and the signal interval is increased for each signal to prevent collision between signals when the interval between two nodes increases. .

1 is a block diagram of a molecular communication system according to an embodiment of the present invention. Referring to FIG. 1, a molecular communication system is composed of a plurality of nodes 10, 20. In one embodiment, a first node 10 of the nodes is a node requesting data transmission and a second node 20 may be a node transmitting data to the first node 10.

The first node 10 and the second node 20 may each be a moving node or one of the first node 10 and the second node 20 may be a moving node and the other may be a fixed node.

2 is a configuration diagram of a molecular communication apparatus according to an embodiment of the present invention. Referring to Figures 1 and 2, a molecular communication device 100 may be provided at a second node 20 for transmitting data. The molecular communication apparatus 100 transmits data by molecular communication between the nodes 10 and 20 whose distance is changed.

In one embodiment, the molecular communication apparatus 100 may include a detection unit 120, a distance prediction unit 140, a symbol interval adjustment unit 160, and a transmission unit 180.

The first node 10 may emit a molecular signal serving as a message requesting data transmission. When the molecular signal emitted from the first node 10 is received by the receiving unit (not shown) of the second node 20, the detecting unit 120 detects the molecular signal emitted from the first node 10.

The distance predicting unit 140 predicts the distance between the first node 10 and the second node 20 based on the local maxima of the number of molecules detected for a predetermined time by the detecting unit 120 .

The symbol interval adjusting unit 160 adjusts a symbol interval at which a symbol is transmitted between the nodes 10 and 20 according to the distance between the nodes 10 and 20 predicted by the distance predicting unit 140 .

In one embodiment, the symbol interval adjuster 160 may reduce the symbol interval as the distance between the nodes 10 and 20 decreases, and increase the symbol interval as the distance between the nodes 10 and 20 increases.

The transmitting unit 180 transmits data to the first node 10 according to the symbol interval determined by the symbol interval adjusting unit 160. Transmitter 180 may transmit data to first node 10 using CSK (Concentration Shift Keying) molecular communication at symbol intervals.

In diffusion-based molecular communication, a series of molecules emitted from the transmitter are assumed to behave according to Brownian motion, and Brownian motion is modeled as a stochastic process. It is therefore probable that the individual molecules emitted by a sender at a particular point at a particular time point will reach a receiver located at a particular point in time. In this molecular channel, the expected number of molecules or concentration c ( r , t ) at time t = t at a distance r distance when the transmitter emits Q molecules at T = 0 is given by Fick's diffusion law The following modeling is possible.

≪ Formula 1 >

In Equation (1), D is a constant that varies depending on the medium, that is, the diffusion coefficient of the medium. In the case where the distance between two nodes changes, the communication method proposed in the present invention will be described in more detail as follows.

3 is a flowchart of a molecular communication method according to an embodiment of the present invention. Referring to FIGS. 1 and 3, the first node 10 emits a molecular signal serving as a message requesting data transmission (S12).

The first node 10 emits a specific molecule A serving as a data transmission request message to the second node 20, which is a communication partner. At this time, the first node 10 can continuously emit Q molecules of A molecules at intervals of t1 seconds successively at x times, and can repeat it with a rest period of t2 after the emission period of t1 * x.

When the first node 10 first sends a data transmission request signal to the second node 20, the second node 20 transmits data in response to this signal. To this end, the second node 20 first detects a molecular signal emitted by the first node 10 for a predetermined time (S14).

The second node 20 predicts the distance between the first node 10 and the second node 20 based on the local maximum value of the number of molecules detected for a predetermined time (S16). When the second node 20 detects m or more molecules A for t3 seconds, the number of molecules detected in t4 seconds is stored in con (n) (n = 1,2,3, ...).

We find the maxima in con (n), store the local maxima in the con (n) values in max (k) (k = 1,2, ..., x) Is stored in I (k). In this case, the local maximum value is con (n) which satisfies con (n-a) <con (n)> con (n + a) and I (n + 1) -I (n)> b. (a is a nonzero integer, b is a constant)

In one embodiment, the second node 20 may estimate the distance between the first node 10 and the second node 20 according to Equation 1 below.

[Formula 1]

(k=1,2,3,...)r (k) =

(k = 1, 2, 3, ...)

(K) is a local maximum value of the number of molecules detected by the second node 20, Q is a first local maximum value of the number of molecules detected by the second node 20, r (k) is a distance between the first node 10 and the second node 20, The number of molecular signals emitted by the node 10, a, is a predetermined constant. From the local maximum values, the distance between the first node and the second node and the moving speed can be predicted using Equation (1).

The second node 20 sets a symbol interval to be used for data transmission from the second node 20 to the first node 10 based on the distance between the first node 10 and the second node 20 S18). In one embodiment, the second node 20 may set the symbol interval according to Equation 2 below.

[Formula 2]

tx (n) = b * r (x) ² + c * r (x) + d

(n = 1, 2, 3, ...)

In Equation 2, tx (n) is a symbol interval, r (x) is a distance between the first node 10 and the second node 20, and b, c, and d are preset constants. b, and c have a value greater than zero.

As in Equation 2 above, the second node 20 is proportional to the distance r (x) to the first node 10 or to the symbol interval tx (n) (n = 1, 2, 3 , ...) can be set.

When a symbol interval is set according to the distance between the first node 10 and the second node 20, the second node 20 transmits data to the first node 10 by a modulation scheme according to the set symbol interval (S20).

초이다.In one embodiment, the second node 20 may transmit data to the first node using CSK (Concentration Shift Keying) molecular communications at tx (n) intervals. For example, the second node 20 transmits a second symbol after tx (1) after the first symbol transmission, and the transmission time of the nth symbol is transmitted after the first symbol transmission

Seconds.

In order to use CSK technique, proper setting of various parameters is needed. The simplest CSK can be encoded in such a way that the bits to be transmitted are 1 when the Q molecules are emitted for t time (or t time intervals), and the bits to be transmitted are 0 when 0 molecules are emitted have. This is for illustrative purposes only, and the modulation scheme of the molecular channel communication of the present invention is not limited thereto.

In another embodiment of the present invention, it is also possible to set the distance between the nodes 10 and 20 step by step, and adjust the symbol interval at the time of the corresponding step change. In this case, even if the distance between the nodes 10 and 20 changes continuously, the symbol interval is adjusted only at the time of step change.

At the first node 10, which is the receiver, data is received from the second node 20 and, for example, total P If more than one molecule is detected, the data is recognized as 1. If less than the number of molecules is detected, the data can be decoded to be recognized as 0. If the number of emitted molecules is changed to 2 ^N (N is an integer of 1 or more), N bits can be transmitted on one unit signal.

In one embodiment, upon data transfer from the second node 20 to the first node 10, it may transmit the symbol interval information set by the second node 20 to the first node 10. The first node 10 can check the symbol interval of the MLC communication in real time through the symbol interval information sent from the second node 20 and perform decoding according to the symbol interval.

For example, as the symbol interval decreases, the first node 10 decreases the reference time interval s for decryption and changes the symbol interval within the reference time interval s according to the reference time interval s, It is possible to decode the data by adjusting the number (P) of detection signals as the discrimination reference.

According to the embodiment of the present invention, when the distance between the nodes 10 and 20 decreases, the symbol interval decreases, and when the distance between the nodes 10 and 20 increases, the symbol interval increases. In this manner, the transmission amount of the molecular communication channel can be increased by using the variable signal interval.

That is, according to the present invention, as the distance between the nodes 10 and 20 decreases, the amount of transmission of the molecular channel can be increased by reducing the symbol interval. Also, since the collision problem may occur between the signals when the distance between the nodes 10 and 20 increases, the signal collision problem can be prevented by increasing the symbol interval as the distance between the nodes 10 and 20 increases.

The method according to an embodiment of the present invention can be realized in a general-purpose digital computer that can be created as a program that can be executed by a computer and operates the program using a computer-readable recording medium. The computer readable recording medium may be a volatile memory such as SRAM (Static RAM), DRAM (Dynamic RAM), SDRAM (Synchronous DRAM), ROM (Read Only Memory), PROM (Programmable ROM), EPROM (Electrically Programmable ROM) Non-volatile memory such as EEPROM (Electrically Erasable and Programmable ROM), flash memory device, Phase-change RAM (PRAM), Magnetic RAM (MRAM), Resistive RAM (RRAM), Ferroelectric RAM But are not limited to, optical storage media such as CD ROMs, DVDs, and the like.

It is to be understood that the above-described embodiments are provided to facilitate understanding of the present invention, and do not limit the scope of the present invention, and it is to be understood that various modifications are possible within the scope of the present invention. It is to be understood that the technical scope of the present invention should be determined by the technical idea of the claims and the technical scope of protection of the present invention is not limited to the literary description of the claims, To the invention of the invention.

10: First node (data receiving node)
20: second node (data transmitting node)
100: Molecular communication device
120:
140: Distance estimation unit
160: Symbol interval adjustment unit
180:

Claims (13)

1. A molecular communication method for transmitting data by molecular communication between nodes whose distance changes,
And adjusting a symbol interval at which a symbol is transmitted between the nodes according to a distance between the nodes,
Wherein adjusting the symbol interval comprises:
Releasing a molecular signal that serves as a message for a first one of the nodes requesting data transmission;
The second node of the nodes detecting the molecular signal for a predetermined time;
Estimating a distance between the first node and the second node based on a local maximum value of the number of molecules detected during the predetermined time at the second node;
Setting the symbol interval to be used for data transmission from the second node to the first node based on the distance between the first node and the second node; And
And transmitting data from the second node to the first node according to the symbol interval,
Wherein the step of predicting the distance between the first node and the second node predicts a distance between the first node and the second node according to Equation 1,
[Equation 1]
r (k) =

Wherein r (k) represents a distance between the first node and the second node,
Max (k) represents a local maximum value of the number of molecules,
Wherein Q represents the number of molecular signals emitted by the first node,
Wherein a is a predetermined constant. The method according to claim 1,
Wherein adjusting the symbol interval comprises:
Reducing the symbol interval if the distance between the nodes decreases; And
And increasing the symbol interval as the distance between the nodes increases. delete delete The method according to claim 1,
The step of setting the symbol interval sets the symbol interval according to Equation (2) below,
[Equation 2]
tx (n) = b * r (x) ² + c * r (x) + d
Tx (n) represents the symbol interval,
Wherein r (x) represents a distance between the first node and the second node,
And b, c, and d are predetermined constants, respectively. 6. The method of claim 5,
Wherein the step of transmitting data to the first node transmits data to the first node using CSK (Concentration Shift Keying) molecular communication at intervals of tx (n). A computer-readable recording medium on which a program for executing the molecular communication method according to any one of claims 1, 2, and 6 is recorded. 1. A molecular communication apparatus for transmitting data by molecular communication between nodes whose distance changes,
A symbol interval controller for adjusting a symbol interval at which symbols are transmitted between the nodes according to a distance between the nodes;
A transmitter for transmitting data to a first one of the nodes according to the symbol interval;
A detector for detecting a molecular signal serving as a message requesting data transmission from the first node; And
And a distance predicting unit for predicting a distance from the first node based on a local maximum value of the number of molecules detected for a predetermined time,
The distance predicting unit predicts a distance to the first node according to Equation (1) below,
[Equation 1]
r (k) =

Wherein r (k) represents a distance from the first node,
Max (k) represents a local maximum value of the number of molecules,
Wherein Q represents the number of molecular signals emitted by the first node,
Wherein a is a predetermined constant. delete 9. The method of claim 8,
Wherein the symbol interval adjusting unit comprises:
And decreases the symbol interval as the distance between the nodes decreases and increases the symbol interval as the distance between the nodes increases. delete 9. The method of claim 8,
The symbol interval adjusting unit sets the symbol interval according to Equation (2) below,
[Equation 2]
tx (n) = b * r (x) ² + c * r (x) + d
Tx (n) represents the symbol interval,
Wherein r (x) represents a distance from the first node,
And b, c, and d are constants set in advance, respectively. 13. The method of claim 12,
Wherein the transmitting unit transmits data to the first node using CSK (Concentration Shift Keying) molecular communication at intervals of tx (n).

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