How to Get Neighbors of a Mobile Node in Wireless Simulation

1. Get the number of nodes in the network

#include <god.h>

God::instance()->nodes();

 

2. In order to use God object in C++ code, in your simluation script, you should have

# Create God
set god_ [create-god $opt(nn)]

for {set i 0} {$i < $opt(nn) } {incr i} {
set node_($i) [$ns_ node]
$node_($i) random-motion 0 ;# disable random motion
$god_ new_node $node_($i)
}

 

 

3. In order to check that if node j is node i's neighbor, use the following function.

God::instance()->IsNeighbor(i , j);

 

4. In oder to use IsNeighbor function in C++ code, either add EnergyModel in simulation script, (please refer to NS Manual Chapter 19 for detail)

$ns_ node-config -energyModel $energymodel \
-rxPower $p_rx \
-txPower $p_tx \
-initialEnergy $initialenergy \

 

or change the IsNeighbor function in mobile/god.cc (disable energy checking)

bool God::IsNeighbor(int i, int j)
{

assert(i<num_nodes && j<num_nodes);

/*
if (mb_node[i]->energy_model()->node_on() == false ||
mb_node[j]->energy_model()->node_on() == false ||
mb_node[i]->energy_model()->energy() <= 0.0 ||
mb_node[j]->energy_model()->energy() <= 0.0 ) {
return false;
}
*/

vector a(mb_node[i]->X(), mb_node[i]->Y(), mb_node[i]->Z());
vector b(mb_node[j]->X(), mb_node[j]->Y(), mb_node[j]->Z());
vector d = a - b;

if (d.length() < RANGE)
return true;
else
return false;

}