PMP 320 stack

Has anyone over lapped 2 PMP320 sectors to allow for more throughput? 

So have both AP's on the same azimuth but a different frequency on both AP's? or 2 33 or 45 degree antenna's?

We want to increase the bandwidth in the sector but have tried to overlap to a  450 the migrate to it but we are having around 10 to 15 db loss from the swap.

We just want to increase the capacity of the sector till a better solution come around we are really waiting till baicells equipment comes along.

Spending 20 to 30k on SM's that we are having bad results with im just having issues justifying the cost of it.

Has anyone had any good experiences with the 450i in 3ghz? 

how does the 450i perform compaired to the 320?

Can't give you details on the 450, we tried one sector embedded in a heavy PMP320 network and could never get it working right - in the end Cambium informed us that our problems would go away once we'd migrated all 320s to 450s, which is not a workable solution for us.  We do have a partner ISP who've deployed several 3ghz 450s in an area that previously had no 3.65ghz service, so no interference issues.

We DO have a few cases where we've overlaid PMP320 sectors atop one another.  If you have an A-B-C-D arrangement like we did (full circle, 4APs, 4 10MHz channels) then you can re-use C atop A, for example.   This presumes of course that you have working reliable sync for all the APs, and comes with the caveat that customers really close to the tower won't be able to reliably use the doubled-up channel, since they'll see too much interference from the opposing AP.

Regarding the performance difference between 450 and 320 in the 3.65ghz band, it's night-and-day.  The 450 has much more capacity, and far better latency (it's not WiMax, after all) but we also experienced a significant reduction in signal levels with two APs side-by-side on a water tank, and two SMs side-by-side on a business with only one of the SMs on at a time - the PMP450 IIRC (this was two years ago) was 8-10dB weaker by the numbers. (and PMP320 sectors 6 miles away dropped sessions like crazy)


Thanks for the reply!

Most of the SM's on this tower are between 0.5 miles to 2 miles away so my main concernedis the sm uplink causing to much interferance.

In general the PMP-450i 3 GHz gear works about the same as the rest, allowing of course for differences in the band and regulations.

We've done what you described. One tower had 2x 90 degree sectors providing 180 degrees of coverage. We stuck a third shooting right between the, so 45 degree overlap, or thereabouts since I think we still had the "kind of a 90 but mostly a 60" degree Motorola/Cambium antennas at the time. All timed off of a CMM4. It worked as well as the rest of our PMP-320. We deploy in 3.65 GHz band. It absolutely required the most possible separation. One thing I'm sure you've noticed about the PMP-320 is that it does NOT tolerate interference.

We traded in most of our PMP-320 for PMP-450 equipment in the 2.4 GHz band. We're way happier, and so are our customers.

I don't encourage waiting on LTE promises. Another company near us played that card and is moving over to PMP-450.

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