a. Each current node searches for other nodes in its
 range of and chooses one that has the maximum
 RSSI value (inversely proportional to the distance),
 then marks it as target node;
b. Request-paired packet is sent from current node to
 target node.
   If target node is idle {
    It responses the request and marks the sender
    as its paired node, then sends back
    confirmation-paired packet to the current node;
    so the target node becomes the paired node of
    current node; GOTO c;
   Else {
    The target node is in the process of pairing
    with other nodes; the current node will wait
    for the time slot of τthen select another target
    node with the second largest RSSI value and
    continue pairing process with reference to a.
   Repeat the above procedure until the current node
   finds its all neighbors are paired with others or the
   time domain is over.
c. Information is exchanged between paired nodes.
If the worst condition of coverage occurs ( )
   A NUMBER is generated randomly in the range
    of [−1, +1] by the node sent the request-paired
    The perceptive direction is clockwise adjusted
    for π/6;
   Else counterclockwise rotates for π/6;
   Taking inverse operation to NUMBER value, the
   sensor obtains and sends it to another
   paired node. Then, the paired node does the same
   operation as follows:
     The perceptive direction is clockwise adjusted
     for π/6;
   Else counterclockwise rotates for π/6;
   end if
d. Force analysis between two paired nodes: each node
  calculates θ, then computes Δφ according to(4)
   and (8) respectively;
Algorithm 2