40MHz and 5ms frame period

For PMP450M and 450i, is a 40MHz channel available at 5ms frame period? Saw posts saying it was due in 2021 but not sure if it ever was released.

Yes, it’s available using the new R21 beta… BUT there are some issues with it that prevent it from providing as much bandwidth as 2.5ms 40MHz, or even 30MHz in some cases.

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Yes, 21.0 supports 40 MHz 5 ms frame at all duty cycles. It was supported in previous released but capped at max of 67% downlink percentage.

Generally 5 ms frame gives increased sector throughput with reduced overhead. However at 30 and 40 MHz due to internal Canopy MAC limitations the throughput to a single Data Channel can actually go down with 5 ms frame.

In general at this time, for 30 and 40 MHz I’d recommend 2.5 ms frame unless you are GPS synchronizing with another 5 ms system. 21.0 made some improvements in 5 ms frame, and we have future improvements planned to further increase it.

For 20 MHz and below, if you are consistently hitting your max Frame Utilization I’d recommend 5 ms frame to give a bump in throughput at a cost of latency.

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