CN105554698A - Biology-friendly data transmission method in underwater sensor network - Google Patents

Abstract

The present invention relates to a biology-friendly data transmission method in an underwater sensor network. Sending or receiving nodes in the sensor network need to avoid the interference on aquatic organism around the sending or receiving nodes so as to realize a biology-friendly communication target. The method provided by the invention comprises: the sending or receiving nodes in the sensor network need periodically monitoring channels to detect whether there are provided biological signals or not; when there are provided underwater creatures, the nodes are configured to locate the creatures; when the creatures move in the coverage area of the node signals, the nodes are configured to stop sending and then send again after the creatures are away from the coverage area so as to prevent the normal communication between creatures from manual signal interference. According to the invention, the position of creatures is determined through the sound power of the creature, and the signal sending time of nodes is arranged according to the motion condition of the creature so as to realize the biology-friendly data transmission.

Description

A kind of biological friendly data transmission method in underwater sensor network

Technical field

The invention belongs to underwater sensor network technical field, relate to a kind of data transmission method.

Background technology

Underwater sensor network is the study hotspot of current wireless communication field, and its research that application prospect promotes underwater sound communication widely is constantly moved towards deeply.Underwater sensor network and other underwater sound coexistence of systems many, as aquatic organism system, Sonar system, offshore oil drilling system etc.Wherein aquatic organism system is the most special.Aquatic organism system is made up of aquatic organism, as white dolphin, and bottle-nosed dolphin etc.Various biologies in aquatic organism system use acoustical signal to communicate, and as population location, colony exchanges, and looks for food.Different with artificial sound system, aquatic organism system is not controlled system, and aquatic organism communicates according to the demand of self all the time, can not comprehend the arrangement of artificial agreement.In addition biosystem is comparatively fragile, and stronger acoustic signals can interfere with biological proper communication, easily causes the confusion communicated between biology.This just proposes better communicating requirement to underwater sensor network.

Do not consider the situation that may produce interference to aquatic organism for current underwater sensor network, the present invention proposes a kind of biological friendly data transmission method.The method requires that aquatic organism signal is monitored in the timing of underwater sensor node, and according to the power information received, biology is positioned, the process of transmitting of reasonable arrangement self simultaneously, stops sending signal, to avoid having a negative impact to biology within the scope of biological elapsed time.

Summary of the invention

The present invention is concerned about the situation that simultaneously there is aquatic organism around underwater sensor network, when considering the communication process of sensor node, designs a kind of biological friendly data transmission scheme.Technical scheme of the present invention is as follows:

A kind of biological friendly data transmission method in underwater sensor network, comprises aspect below:

(1) underwater sensor network is made up of sending node and receiving node, acoustical signal is used to carry out transfer of data between transmitting-receiving node, the coverage of the signal that each sensor node sends is identical, be the circle of r at two dimensional surface coverage radius, if when biology is in signal cover, think that the signal that node sends can produce interference to biology.

(2) set the power of biological sounding as P; The circle of the coverage of bio signal to be radius be R, in biological motion process, when this circle covers sensor node, node can detect biological existence by monitor channel, if biological motion speed is v, moves as straight line;

(3) transmitting-receiving node in sensor network is carrying out in data transmission procedure, need to avoid the underwater sound biology to surrounding to produce interference, to realize biological friendly communication target, method is: node periodically detects bio signal, and according to its position of power allocation of bio signal; According to the biological site information that adjacent twice location obtains, determine biological movement locus; Calculate and biological in node signal coverage, stay path and residence time; When in biological motion to node signal coverage, node suspends and sends signal, and the lasting duration of time-out is t; After coverage is left in the non-entering signal coverage of biology or motion, node can continue to send.

The present invention by the position of biological sounding power allocation biology, and arranges node to send the time of signal according to the motion conditions of biology, to realize biological friendly transfer of data.

Accompanying drawing explanation

Fig. 1. with transmitting-receiving node line place straight line for X-axis, the perpendicular bisector between transmitting-receiving node is Y-axis, sets up plane right-angle coordinate

Fig. 2. biological motion is to A point, and node N detects biological existence

Fig. 3. calculate and biological within the scope of coverage, stay length and residence time (situation one: transmitting-receiving node M, N all may interfere with biocommunicaion)

Fig. 4. calculate and biological within the scope of coverage, stay length and residence time (situation two: only receiving node M may interfere with biocommunicaion)

Fig. 5. calculate and biological within the scope of coverage, stay length and residence time (situation three: transmitting-receiving node all can not interfere with biocommunicaion)

Embodiment

According to the communication scenes arrived involved in the present invention, need to set up plane right-angle coordinate and concrete summary of the invention is described.It is the circle of r that the signal that sending node N and receiving node M sends can be reduced to a radius in two dimensional surface, now with the straight line at the circle center line connecting place of two circles for X-axis, the perpendicular bisector of two circle circle center line connectings is Y-axis, sets up plane right-angle coordinate, as shown in Figure 1.If the distance between sending node N and receiving node M is d, then the coordinate of sending node N is the coverage sending signal is equation the inside of corresponding circle and border; In like manner the coordinate of receiving node M point is its coverage sending signal is equation the inside of corresponding circle and border.

Whether the scheme designed by the present invention needs node periodically monitor channel, detect and have bio signal to occur.By monitor channel continually, node can detect the existence of surrounding biologic in the very first time.Node first time, when bio signal being detected, need to position biology according to the power of the bio signal received, if now biology is positioned at A point, coordinate was (x ₁, y ₁).Posterior nodal point still can monitor channel, if still have received bio signal, then can again position the position of biology, if now biology is positioned at B point, coordinate is (x ₂, y ₂), as shown in Figure 2.

According to the position of A, B 2, node can obtain the track of biological motion.In the listening period that interval is very short, can thinking that biological movement locus is a straight line, therefore by the coordinate of A, B 2, the equation of locus of biological motion can being tried to achieve, for meeting the straight line L of formula (1):

$y=\frac{y_1-y_2}{x_1-x_2}x+y_1-\frac{y_1-y_2}{x_1-x_2}{x}_1$ Or $\frac{y_1-y_2}{x_1-x_2}x-y+y_1-\frac{y_1-y_2}{x_1-x_2}{x}_1=0$ (1)

The angle of its cathetus L and X-axis positive axis is the slope of θ, L

According to the coverage that movement locus and the transmitting-receiving node of biology transmit, the path of node through signal cover can be calculated, and the path of biology in signal cover.Cross some N and put M and do vertical line respectively to straight line L, be respectively a C and some D with the intersection point of L.The length of line segment CN for a N is apart from the distance of straight line L, the length of line segment DM for a M is apart from the distance of straight line L, circular is as follows:

Point N is apart from the distance of straight line L: $\stackrel{\‾}{CN}=\left|\frac{\frac{y_1-y_2}{x_1-x_2}\×\frac{d}{2}+y_1-\frac{y_1-y_2}{x_1-x_2}{x}_1}{\sqrt{{\left(\frac{y_1-y_2}{x_1-x_2}\right)}^2+1}}\right|$

Point M is apart from the distance of straight line L: $\stackrel{\‾}{DM}=\left|\frac{\frac{y_1-y_2}{x_1-x_2}\×(-\frac{d}{2})+y_1-\frac{y_1-y_2}{x_1-x_2}{x}_1}{\sqrt{{\left(\frac{y_1-y_2}{x_1-x_2}\right)}^2+1}}\right|$

By the length of CN with the length of DM compare with the covering radius r of transmitting-receiving node signal, correspond to following three kinds of situations respectively:

1. situation one: and illustrate that the signal cover of biological motion track and transmitting-receiving node has intersection point, namely the signal of transmitting-receiving node all likely interferes with biocommunicaion, as shown in Figure 3.

In this case, straight line L and circle Ο ₁intersect at an E, with circle Ο ₂intersect at a F, line segment EF is exactly biological path in transmitting-receiving node signal cover, and namely biological be biological residence time within the scope of coverage in the line segment EF range of motion time.Now calculate the length of EF line segment.As shown in the figure, cross some N and put M and do vertical line respectively to straight line L, be respectively a C and some D with the intersection point of L.And cross the parallel lines that some D does X-axis, intersect at a G with line segment CN.The length of line segment EF can be divided into three parts to calculate, as follows respectively:

(1) length of line segment CE is calculated: the length of known line segment CN in right-angled triangle CEN,

$\stackrel{\‾}{CE}=\sqrt{{\stackrel{\‾}{EN}}^2-{\stackrel{\‾}{CN}}^2}=\sqrt{r^2-\frac{{(\frac{y_1-y_2}{x_1-x_2}\×\frac{d}{2}+y_1-\frac{y_1-y_2}{x_1-x_2}{x}_1)}^2}{{\left(\frac{y_1-y_2}{x_1-x_2}\right)}^2+1}}$

(2) length of line segment CD is calculated:

DGNM is parallelogram, therefore has

From the slope of straight line L,

$tan\∠\mathrm{\θ}=k=\frac{y_1-y_2}{x_1-x_2}$

Therefore have: $\cos \∠CDG=\±\sqrt{\frac{1}{1+k^2}}=\±\sqrt{\frac{1}{1+{\left(\frac{y_1-y_2}{x_1-x_2}\right)}^2}}=\±\sqrt{\frac{{\left(x_1-x_2\right)}^2}{{\left(x_1-x_2\right)}^2+{\left(y_1-y_2\right)}^2}}.$

In right-angled triangle DEG, $\stackrel{\‾}{CD}=\stackrel{\‾}{DG}\×|cos\∠CDG|=d\×\sqrt{\frac{{(x_1-x_2)}^2}{{(x_1-x_2)}^2+{(y_1-y_2)}^2}}$

(3) length of line segment DF is calculated: the length of known line segment DM in right-angled triangle DFM,

$\stackrel{\‾}{DF}=\sqrt{{\stackrel{\‾}{FM}}^2-{\stackrel{\‾}{DM}}^2}=\sqrt{r^2-\frac{{(\frac{y_1-y_2}{x_1-x_2}\×(-\frac{d}{2})+y_1-\frac{y_1-y_2}{x_1-x_2}{x}_1)}^2}{{\left(\frac{y_1-y_2}{x_1-x_2}\right)}^2+1}}$

The length of line segment EF can be calculated by above-mentioned three steps namely

2. situation two: biological motion track only has intersection point with the signal cover of a node, namely only has the signal of a node likely to interfere with biocommunicaion.Now with for example is described, namely the signal of sending node can not interfere with biocommunicaion, and the signal of receiving node may disturb biocommunicaion, as shown in Figure 4.

In this case, straight line L and Ο ₁there is no intersection point, straight line L and Ο ₂intersect at an E and put F.Line segment EF is biological motion path in receiving node range of signal, now calculates the length of line segment EF

The length of known line segment DM in right-angled triangle DEM,

$\stackrel{\‾}{DE}=\sqrt{{\stackrel{\‾}{EM}}^2-{\stackrel{\‾}{DM}}^2}=\sqrt{r^2-\frac{{(\frac{y_1-y_2}{x_1-x_2}\×(-\frac{d}{2})+y_1-\frac{y_1-y_2}{x_1-x_2}{x}_1)}^2}{{\left(\frac{y_1-y_2}{x_1-x_2}\right)}^2+1}}$

The length of line segment EF: $\stackrel{\‾}{EF}=2\stackrel{\‾}{DE}=2\×\sqrt{r^2-\frac{{(\frac{y_1-y_2}{x_1-x_2}\×(-\frac{d}{2})+y_1-\frac{y_1-y_2}{x_1-x_2}{x}_1)}^2}{{\left(\frac{y_1-y_2}{x_1-x_2}\right)}^2+1}}$

3. situation three: biological motion track and transmitting-receiving node are all without intersection point, and the communication namely between transmitting-receiving node can not interfere with biocommunicaion, as shown in Figure 5.

In this case, the communication between transmitting-receiving node does not need to consider the biological impact existed, and can carry out the transmitting-receiving of data according to existing communication process.

For situation one and situation two, according to the length of the line segment EF calculated and combine biological speed v of moving under water, biology can be calculated and leave signal cover time t used from entering signal coverage to motion,

Because node is at biology the existence that A point place just detects it, but due to the distance of AN point-to-point transmission be greater than the radius r of the coverage of node signal therefore the biology being in A position can't receive the signal of sensor node, and now transmitting-receiving node still can proper communication; Simultaneously when biological motion gradually away from time, biological and internodal distance also will be greater than the coverage of signal, and therefore node can recover normal data transmission procedure.

According to above-mentioned calculating, node can arrange biological friendly transmitting-receiving scheme, is specially:

(1) node periodically detects bio signal, and according to its position of power allocation of bio signal;

(2) according to the biological site information that adjacent twice location obtains, biological movement locus is determined;

(3) calculate biological in node signal coverage stay path and residence time t;

(4) when in biological motion to node signal coverage, node suspends and sends signal, and the lasting duration of time-out is t; After coverage is left in the non-entering signal coverage of biology or motion, node can continue to send.

Claims (1)

1. a kind of biological friendly data transmission method in underwater sensor network, comprises aspect below:

(1) underwater sensor network is made up of sending node and receiving node, acoustical signal is used to carry out transfer of data between transmitting-receiving node, the coverage of the signal that each sensor node sends is identical, be the circle of r at two dimensional surface coverage radius, if when biology is in signal cover, think that the signal that node sends can produce interference to biology.

(2) set the power of biological sounding as P; The circle of the coverage of bio signal to be radius be R, in biological motion process, when this circle covers sensor node, node can detect biological existence by monitor channel, if biological motion speed is v, moves as straight line;

(3) transmitting-receiving node in sensor network is carrying out in data transmission procedure, need to avoid the underwater sound biology to surrounding to produce interference, to realize biological friendly communication target, method is: node periodically detects bio signal, and according to its position of power allocation of bio signal; According to the biological site information that adjacent twice location obtains, determine biological movement locus; Calculate and biological in node signal coverage, stay path and residence time; When in biological motion to node signal coverage, node suspends and sends signal, and the lasting duration of time-out is t; After coverage is left in the non-entering signal coverage of biology or motion, node can continue to send.