Odd question about PMP450 colocation with BH20


Is there any documentation or tips with regards to colocation of an old bh20, and a PMP/PTP450?  

Up until yesterday, I'd always assumed the BH20 was essentially a PMP100, and treated it as such by looking to the PMP100/450 colocation tool for how to manage this.  However, I'm concerned now that the bh20 and PMP100s are not as similar as initially thought, in-terms of their timing. 

I have a BH20, some PMP450 Access Points, as well as some PTP450s on the same tower.  So I just want to make sure I'm not loverlooking something by relying on the Colocation tool, if in fact it's not intended for use with a BH20.

So I'm just looking for some clarification.  Can anyone answer this one for me?

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I have forwarded this to our support and development teams.

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Any update on this Ray?  I really appreciate it.

I have escalated this with the support team.

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Sorry for the stupid question, but what is a BH20? Is it a PTP 100? You can send me a http://<IP_address>/engineering.cgi to charlie.galik@cambiumnetworks.com and I can take a look at the exact product.

But yes, Frame Calculator running on the radios is always the best way to do this. Have one web page open on each radio while it's running and run it's Local Frame Calculator web page with the parameters in it. Ensure neither AP/BHM Transmit End time is after the any other AP/BHM Receive Start time.

Backhaul can get a little tricky as it's exact frame is setup after the BHS registers at its exact distance. That is why later versions of firmware added in a "SM/BHS One Way Air Delay" field. But I'm not sure if the product you have has that or not. You can look at the registered BHS to get its distance in nanoseconds to add to the Frame Calculator.

My apologies for the delayed response. Did you open a ticket with customer support on this issue?


Hi Charlie,

Yes, a BH 20 is the 20 Mbps backhaul also known as a PTP 100.