Minimizing the Adverse Effects of Asymmetric Links: A Novel Cooperative Asynchronous MAC Protocol for Wireless Sensor Networks

. 2019 May 26;19(10):2402. doi: 10.3390/s19102402

Algorithm 1 Tree Formation.

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$P_{u}$ = ∅ ▹ initially parent is empty
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$Q_{u}$ = ∅ ▹ initially buffer for parent is empty
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for each Node $i \in N_{u}$ do ▹ $N_{u}$ is the set of all neighbor nodes of u in G
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if $P_{u}$ is empty then
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if $d_{i, B S}$ < $d_{u, B S}$ then
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$P_{u}$ =i ▹ Assign current node as parent
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add i in $Q_{u}$
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end if
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else
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if ( $d_{i, B S}$ < $d_{u, B S}$ && $d_{i, u}$ < $d_{u, P_{u}}$ ) && $h c o u n t_{i, B S}$ ≤ $h c o u n t_{P_{u}, B S}$ then
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$P_{u}$ =i
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add i in $Q_{u}$ ▹ Add current node into the parent queue
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end if
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end if
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end for
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Sort $Q_{u}$ according to distance and hop count
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for∀ $Q_{u}$ each element in buffer do
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$P_{u}$ = Dequeue( $Q_{u}$ )
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Ack ←GetAcknowledgement( $P_{u}$ )
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if (Ack ≠ Overflow) then
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Exit from loop and $P_{u}$ is the parent of u
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end if
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end for