Optimization of Self-Directed Target Coverage in Wireless Multimedia Sensor Network

Algorithm 2

The algorithm of multinode single-target self-directed coverage.

Input: set of multimedia sensor nodes 𝑆, interested target 𝑇_𝑘, sensing radius 𝑅_𝑠, FoV vertex

angel 𝜃, sensing direction 𝑆𝐶 corresponding to node set 𝑆

Output: 𝐶_𝑇𝑘(𝑠_𝑖)

Define 𝑠_𝑖; //node selected to cover interested target, 𝑠_𝑖∈𝑆

Define RotateDirection; //rotated direction of node, value as CLOCKWISE or ANTICLOCKWISE

Define RotateAngle; //rotated angel of node

Let 𝐵=Ø; //for node set of FoV disk coverage target 𝑇_𝑘

Let EC_𝑇𝑘=Ø; //for coverage expectation of node to interested target in B;

FOR each 𝑠∈𝑆

  Calculate 𝑑(𝑠,𝑇_𝑘)

  IF 𝑑(𝑠,𝑇_𝑘)≤𝑅_𝑠 THEN

     𝐵=𝐵∪{𝑠};

     Calculate ∠𝑇_𝑘𝑠𝐶

     Calculate EC_𝑇𝑘(𝑠)

     EC_𝑇𝑘=EC_𝑇𝑘∪{EC_𝑇𝑘(𝑠)};

  END

END

EC_𝑇𝑘(𝑠_𝑖)=MAX(EC_𝑇𝑘);

𝑠_𝑖 = 𝐵[𝑖];

IF 0<∠𝑇_𝑘𝑠_𝑖𝐶≤𝜋 THEN

  RotateDirection = anticlockwise;

  RotateAngle = ∠𝑇_𝑘𝑠_𝑖𝐶;

END

IF 𝜋<∠𝑇_𝑘𝑠_𝑖𝐶<2𝜋 THEN

  RotateDirection = clockwise;

  RotateAngle = 2𝜋−∠𝑇_𝑘𝑠_𝑖𝐶;

END

ROTATE(𝑠_𝑖, RotateDirection, RotateAngle); //𝑠_𝑖 rotated RotateAngle to RotateDirection

𝐶_𝑇𝑘(𝑠_𝑖)=1

RETURN 𝐶_𝑇𝑘(𝑠_𝑖).