|
|
|
According to the
two-ray ground model, the signal power strength p at the receiver has the
relation with the distance between the sender and receiver: d to the 4. P1 to
p3 is the power strength that receiver received at different time. Ps is the
signal strength threshold at the
receiver. So the t is the link breakage time for node A and B. From above
equation, we can calculate the t. When node B is receiving unicast packets
from A, it uses sliding window to calculate the link breakage time, and only
calculate the decreased signal power strength.
|
|
|
|
The conditions
for the prediction algorithm are:
|
|
at least three
unicast packets are needed to obtain correct prediction time.
|
|
And during the
time we make prediction and link breaks, we assume two nodes will maintain
their speed and direction.
|
|
|
|
So if one of
them changes movement pattern, the prediction will not be accurate unless
receiving another three packets.
|
