Overlapping APs with 5.8ghz/30mhz

I would like to have opinions on the AP layout shown below. The reason for this new layout is one AP (AP6) is carrying 50% of all my traffic and AP1 and AP5 are filling up quick. The original config was 6 PMP450s with 60deg sectors (all Sattelite timed via CMM4). AP 6 was swapped for a 450i 90deg sector and is at its limit now. The new config will make AP6 a 450i with a 60deg sector and AP1 and AP5 450i with 90deg sectors. 

These are all 5.8ghz. Adding frequency (or additional equipment) is not really an option on this tower. Given 5.8ghz in 30mhz channells, the frequencies chosen should give a minimum of 17.5mhz of seperation between any adjacent or overlapping APs.

The idea is to offload some of the traffic from AP6 to AP1 and AP5. I will keep all the SMs that are close to the BoreSight of AP6 on AP6 and Keep AP1 and AP5 SMs away from thier common border.

Any advice or alternatives would be greatly appriciated!

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I know this may not be an option, but replacing one or more of your APs with 450m will likely GREATLY increase your sector capacity.  How many subscribers are connected and what are the rate plans you offer your customers?  Knowing this may help you determine the benefits of replacing sectors with cnMedusa.

You can plan your sectors within LINKPlanner, using the current APs, and seeing the total expected capacity (to compare to what you're actually seeing), then replace the AP with a 450m, and see what you might expect simply by making this one change.  I suspect you'll see 2 to 3 times the total capacity within that sector.

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One thing I forgot to mention, is that this capacity increase comes without any increase or change in frequency usage... because of the Multi-User MIMO capability of the cnMedusa product, you make better use of spectrum, so this capacity increase comes without changing spectral use, nor any changes to the SM hardware at all.

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The pysical size of the 450m is prohibitive for the leased space I have on this tower. 

I swapped a 450m in Link Planner for one AP but it showed no improvement in throughput. 

. I offer 3 Tiers of service. A. 3/1 B.7/3 C.15/5  All tiers offer burst bucket to allow 50%-100% increase in DL for the first 300mb to 900mb of DL.

Most of the customers are on the 7/3 tier. DL/UL is split 75%/25%in the AP. During peak times it regularly hits 70mbps+ download.

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@AJones wrote:

The pysical size of the 450m is prohibitive for the leased space I have on this tower. 

I swapped a 450m in Link Planner for one AP but it showed no improvement in throughput. 



Hi AJones,

It seems fairly unlikely a 450m wouldn't give an increase in throughput. Did you have it in sector or Mu-MIMO operating mode, need to select Mu-MIMO to see the boost.

I'm happy to have a quick look through the linkplanner project if you want any help.

best regards,

Andy.

You are correct. I did not have the operating mode set to Mu-MIMO. It did show a jump from 53 to 171mbps throughput with Mu-MIMO. Admittedly, I do not use link planner to its full potential. So other settings may be slightly off as well. I mainly use it to see the terrain between AP and SM. If it does not show a mountain between them, I roll a truck and do onsite testing before I quote install prices to potential customers.

In this case I did not research 450M any further once I realized

A. The physical size would not allow me to install it at this location. 

B. If it had a 180deg beamwidth, maybe I could replace 3- 60deg APs. (2- 90deg 450Ms replacing 3-60deg 450s is not viable at this location.

C. Channel selection is 10, 20, or 40mhz.-- All my other APs use 30mhz. I would have to reduce thier channel size for timing purposes. (Or will a 450 run 40mhz channel?)

Anyway,  for this purpose lets agree that a 450M will not work. Given that I have (3) 450i APs with 2- 90deg and a 60deg sector antenna, will this configuration (shown above) work? 

I think you should be OK, after all you already have some overlap in your current setup.

It would be nice to hear experience of anyone who has done similar though, I'm not an RF planning expert - linkplanner should be your friend here.

What frame size are you using ? moving from 2.5 ms to 5ms frame can give up to 10% boost in throughput which may help in the short term.

I know 450m is out of the picture but would like to clarify a couple of things

All 5GHz PMP450 products, including 450m, support 5, 10, 15, 20, 30 & 40 MHz channels (2.5ms frame only at the moment for 30 & 40 MHz in 450m).

450m can work across 120 degrees (with 6dB roll off vs. 3dB roll off for 90 degrees)

best regards,

Andy.

If your tower space is limited, but you have a decent amount of clean spectrum, you could try breaking up the sector into 3 or 4 30deg RF elements horns connected to 450i connectorized radios.

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In lieu of deploying a 450m (which is really what would benefit you most :)), the suggestion of using more 450i APs with narrower sectors is something that many folks have done.  The RF elements horn antennas provide a great tight beam pattern with very good Front-to-Back isolation, which will prevent frequency pollution in areas you don't want that signal.

I agree with Andy that you should be ok with the path you're going down already, but Eric presents another option in case you want additional capacity, or to further optimize... again, in lieu of the Massive Multi-User MIMO lift that you'd get with cnMedusa!

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I have done both(Medusa and 30 degree horns), if your sm are far away, or not so many, go with horns. If your sm are not so far away, or you have many; Medusa is the best option.

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