Average #of SMs per tower and highest # of SMs on a tower

Just trying to gather some data on tower density, SM density etc. Looking for some general input in the following area:

  • In your largest tower, how many SMs do you serve?
  • What is the average #of SMs on a tower?


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Our most customer-dense site currently serves 372 subs I think.

I’m not sure what our average number of SMs per site is though, as it varies widely based on site. But if I had to guess, an average would probably be about 50 subs. We have many small sites and only a handful of macro sites. I guess it’s time to do some math.


Thanks Jake. Appreciate the response.

We are averaging 30 subs per sector/omni. Some higher some lower.

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average rate plan and channel size?


Due to lack of clear channels we are running 20Mhz at 50/50.

Average package rate would require pulling current configs from the radius database for all radios as it is dynamically set with the eap-ttls auth. Suffice to say that our smallest user package is 4/1Mbps and our highest currently is 75/15Mbps. Internal bridging for multi-site clients can have 100/100 with a specified uplink. Then again this is not what is asked in the OP post.

wholly on topic, # of subs per tower is limited by channel size, spectrum is not unlimited, rate matters, capacity per AP is not unlimited.
IIRC the max capacity per EPMP AP is defaultly 128 subs.
20 mhz 50/50 on a 30 sub omni has substantially limited concurrent end user capacity.
It most definitely matters if its a marketing driven question. Nobody cares how many subs alone can be served from a single site we have 12 EPMP APs at a site, we can serve 1536 people all the dialup QOS they want

the question was average # of subs per tower and highest # per tower so NOT on topic.
Now to extend your lateral thinking, number of sectors per tower is relevant as the number of subs per tower is based on the version of epmp AP and the number of sectors. eg a e1k/e2k can have 128 but a e3kL can only do 64 and the e1k-Lite only 10 (unless you get an upgrade key), quite the big difference in SM capacity per tower.

I have not personally seen any limitation of connected SMs based on the channel size, providable bandwidth yes but not connected. Spectrum is not unlimited nor clean in our area so keep in mind its a compromise for our situation that may not be seen by you. Marketing does not care what bandwidth you offer as that is your choice, the radio is still capable of offering more even if you don’t offer it.
Yes the use of an omni places limits on us, more noise from a wider inbound angle but again spectrum is also key. If we had two 40Mhz channels without interference we would have taken them, but that is not so and we are lucky to have 10Mhz let alone 20 (which is the smallest for e3k/F300). Another factor you are ignoring is do you put up 4 sectors to feed 30 subs from all angles? NO! you place as few of resources as possible that will still provide the service you are promising. The tower does not make any money while you are paying off the ROI time. Further, considering that signal strength and signal to noise determines modulation rates, smaller closer towers makes more sense but that also means compromises in resources applied, ROI time and reduced density availability (which increases ROI time) but provides a much more stable system and happier clients (which are paying you so you need to keep them happily paying you). If there is a need for a sector emplacement over an omni, then it is done then again it isn’t a sin (I still don’t know where this myth comes from) to mix an omni with sectors either if you have the spectrum at that location. In fact we have two such towers where there is an omni for the main use and we have a sector deployed to provide additional bandwidth for several clients whom needed/wanted more than the available capacity of the AP on the omni.
Our choice of 50/50 is also a compromise based on what we need to accomplish, different companies have different needs and goals. For us having 75/25 would place a heavy burden on upstream since we have large symmetric streams crossing our network and with more clients using video services both for video calls and for remote surveillance systems where the stream is pushed to a cloud services provider it makes more sense for our flows to be 50/50. Since our backhaul/inter tower flows are 50/50, for interference mitigation having everything timed the same to a common sync source is paramount since again spectrum is just not available. Of course careful planning and implementation are required, but it is nice to get 300+mbps in several back to back links on the same channel or even perform LACP on two links between the same towers to get more bandwidth (fiber right of ways are extremely hard to get here) where moving to a license link or a higher bandwidth ptp radio is not practical for the site.

All of the above Marketing does not care about since its the decisions that determine that we are autonomous from our peer networks and thus is moot. What they care about is how to put the best foot forward, which in terms of density deployed only the average number of SMs per tower and highest count on a tower is being considered. If you really wanted to split hairs then you would ask for the number of towers and AP count too but that isn’t what matters. They are simply looking to enumerate average density per tower and what the highest density at a site is without regard to the number of sectors involved.

To put it another way: Cisco, HP, Broadcom, D-Link all tout how many 1GB, 10GB and 100GB ports are deployed, but not the breakdown of which devices they are deployed on. And it really doesn’t matter that its in a Cisco x65xx or a HP Proliant 4x class, they are simply deployed ports and its a marketing metric even if its not the whole story, but it is the story they are wanting to tell.

Very Rural here, largest city pop 2,500 all but a few “towers” are water towers.

Largest tower AP/SM (4x450i 4xePMP 5G 1xePMP 2.4G in process of adding 450i and 5G APs) / 198 SMs

Average number of SM’s on a tower around 80

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