Syncing Alvarion and Cambium

One of our competitors is adding a bunch of Alvarion equipment, and I'm trying to coordinate with them to get our PMP450s synchronised with them.

They have told us that their equipment is set to 32:15 TDD ratio with GPS sync.  I'm guessing that's akin to DL/UL slots, which would indicate a 68% down/32% up, but I'm not sure what their frame length is.

What do I need to do on our end to match those settings?

Do you know if they're using an 802.16e WiMAX-based system? If they are, it MIGHT be possible. More recent firmware revisions for PMP450 allow for 5ms frame times, which make it possible to sync with PMP320 (which is 802.16e WiMAX-based).

There's a webinar here with some information on migrating from PMP320 to PMP450.

I've also attached a technical white paper from Cabmium on migration as well.

Good luck!

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It's a WIMAX .16E product, rather than the .16D the 320 is based on.  I've already got a fair bit of practice working with 320s and 450s on the same network since we're currently migrating over.  We're keeping our 320 and 450 freqs well apart from one another to prevent interference, but we did use the colocation tool to match them.  The problem is that the tool limits me to DL/UL ratios the 320 uses, so I can't use it to test the 68% DL the Alvarion unit is using.

From doing some digging into the WIMAX frame configuration, it should be using 5 ms frame sizes.  I can easily match our download to upload and contention slot ratio to match theirs, but I have no idea what their TTG and RTG.  Are those defined by the standard, or are they up the manufacturer?  Is the length of the individual slots in a WIMAX frame of a fixed width or do they change when the TTG and RTG change in a similar manner to how the 320 changed the timing when extended range was enabled?

The PMP320 IS 802.16e... that being said, there are some major differences between d and e (I've attached a Motorola white paper on the subject).

I'm not familiar enough with 802.16e or Alvarion's implementation to tell you what the TTG and RTG settings would be or how to make them place nice with PMP450.

I think what I would do in your situation, is take whatever standard/run of the mill settings that a PMP320 might use, and try to replicate these as closely as possible on the Alvarion system, and then use the migration guide to sync your PMP450. This will of course require your competitor to work with you very closely and possibly alter their settings on the Alvarion to better help you reach a DL/UL compromise.

Of course, much of this is speculation and will require some testing to determine if it's possible. I did some quick research online and have not found anyone specifically trying to sync PMP450 with Alvarion 802.16e... that being said, assuming that you can duplicate similar settings to the PMP320 on the Alvarion platform, it might be possible.


Here is something we got from the other company about the Alvarion frames.

They're doing 10 MHz at 32:15, so their timing should be:
DL end: 3292.8 us

UL Start: 3398.5 us

Hopefully this helps other folks trying to coordinate with WIMAX stuff.