Upcoming CBRS release - part 2

The second video related to Release 20.2 and operation in the CBRS band is now available.
Here are the links to both part 1 and part 2 of the video series:

Part 1:

Part 2:

Here is also the link to the forum post related to the first video:

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Are the slides available?

Here are the slides, apologies for the delay in getting these posted.

CBRS Release 20.2 v5.pdf (449.7 KB)

The part 2 video says video unavailable, removed by uploader. Am I doing something wrong?

Not sure what happened there Ken… will work on getting that fixed.

Update: Fixed, thanks!

Here are the slides for Part 2 as well.

MultiGrant_and_PAL_Support_Part2_v2.2_no_audio.pdf (741.9 KB)

What would be really cool and helpful is config options for timing parameters per channel bandwidth. Even if the AP has to reboot for it, but I would hope it could be reboot-less at least for 450 and 450i APs. This I think is going to be the big challenge with the automagic freq/bw changes.

I agree this would be nice, but it’s probably not needed for 99% of cases. After playing around with the link calculator, every combination of channel widths provides proper timing EXCEPT for 5MHz channel widths. e.g. you have multiple AP’s using a 20MHz channel width, and then CBRS causes an AP to reduce down to a 5MHz channel (assuming you have this as a valid channel width, most people will not want this), then you’d have timing issues.

We have considered more changes in this area, and appreciate feedback to understand how much it is needed. If the AP calculates a new duty cycle (after changing BW) to align its new frame to the previous frame (with the wider channel), would it be ok for the AP to automatically apply it and reboot?
As noted in the other comment, this case is very rare. It can occur when the BW changes dramatically (for example from 40 MHz to 10 MHz) and the sector has a very small max range.

Cambium recommended using channels based on 10 Mhz and 5 Mhz increments, 3550 MHz 3560 Mhz 3565 MHz etc. There was a template provided to add these channels via Maestro.

I thought that the APs now inform the SMs which channel they will be shifting to automatically, so they can more quickly reassociate. Does that feature not work with the CBRS implementation? If it works, then no real need to apply the template they provided right?

The CBRS follow me feature will only work with SM’s that are online. SM’s that are offline that don’t have the channel plan will not reconnect.

Wont reconnect at all without site visit, or just needs to get a grant?

You’ll either need to roll a truck, or move the AP back to the channel and channel width that the SM was previously working on.

scan lists get wiped?

No, the scan list does not get wiped.

than shouldnt it pull a new grant?

It has nothing to do with grants.

So let me begin again… If the SM is online when the SAS forces an AP to move channels or channel width, SM’s will follow, regardless of what channels and centers are in their list. If the SM is offline when this happens, and it don’t have the AP’s new center/width in their list, it will not be able to connect. A truck roll will be needed to get them back online OR, the AP will need to be moved to a channel/width that is in the SM’s list.

I see, you’re talking about if its not already in the list, I misunderstood. I thought existing list was somehow not going to work

Having the full list on all SM’s acts as an insurance policy of sorts if one of the SM’s is offline when an AP channel/width change is made.