Multi-Link Operation with Enhanced Synchronous Channel Access in IEEE 802.11be Wireless LANs: Coexistence Issue and Solutions

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. 2021 Nov 29;21(23):7974. doi: 10.3390/s21237974

Algorithm 1 Proposed multi-link channel access procedure of an STA.

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while the STA has a packet to transmit do
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$b \leftarrow Rand [0, C W - 1]$ # Pick a new backoff count value
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while $b! = 0$ do
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if Other STA has completed a backoff process and is about to transmit a packet then
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if the channel is idle for PIFS then
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Transmit the packet in the given channel
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if the MLD uses the Switch Scheme then
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$(C W_{m i n}, C W_{m a x}, C W) \leftarrow (C W_{m i n B}, C W_{m a x B}, C W_{m i n})$
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Start a timer with an expiration time of $t_{s w i t c h}$
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end if
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if the MLD uses the Doubling Scheme then
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$C W \leftarrow min (2 (C W + 1) - 1, C W_{m a x})$
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end if
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if the MLD uses the Repick Scheme then
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$b_{o l d} \leftarrow b$ , $b \leftarrow Rand [0, C W - 1]$ # Repick a new backoff count value
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end if
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if the MLD uses the Compensation Scheme then
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$b \leftarrow b + b_{o l d}$ # Add the remaining backoff count to the current value
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end if
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end if
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end if
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while the channel is sensed busy do
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Sense the channel for DIFS
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end while
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$b \leftarrow b - 1$ for every idle $T_{s l o t}$ duration
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end while
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Transmit the packet in the given channel
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if the MLD uses the Switch Scheme $t_{s w i t c h}$ has expired then
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$(C W_{m i n}, C W_{m a x}, C W) \leftarrow (C W_{m i n A}, C W_{m a x A}, C W_{m i n})$
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end if
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if the transmission succeeds then
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$C W \leftarrow C W_{m i n}$
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else
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$C W \leftarrow min (2 (C W + 1) - 1, C W_{m a x})$
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end if
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end while