Product Recommendations, questions (C5c, B5c)

[Eli]

Hello everyone.

I am in the process of trying to establish a link from my central office tower, to my personal residence 10.4 miles away. The radio at the CO would be at 190 ft. and I currently have 70 ft. of height at my home with the potential for another 16 ft. if absolutely necessary. Elevation at my home is 115 ft. higher than the CO.

I have used the Mimosa Design tool to build the link, and get similar SNR on both the B5c and C5c radios. I understand that the Design Tool assumes direct line of sight, but living in south east Michigan I have a decent amount of trees to contend with. Having some experience with wireless deployment I know the LoS requirements for other radios, but I’ve never used Mimosa products as of yet ( we have customers on older Airspan, Alvarion, and Backhaul to our towers with Radwin).

My question therefore is two-fold; How wide a path through local trees do I need for the C5c or B5c to operate effectively? How much of an impact will a small woods patch mid link with some potential fresnel obstruction be? Assuming the 5 GHz band is populated, but not maxed out, would I be able to get away with using C5c radios for my link? Just hoping to get some feedback from anyone who has real world experience with these products as opposed to making a purchase based on a calculator not designed to consider all the variables. Keeping in mind I’d like to keep my cost down, but am willing to spend more for quality of service.

My bandwidth requirements are not huge, anything 10 Mbps or higher would be a vast improvement from what I have currently. Ideally I’d like to see something in the 50-100 Mbps range for future heavier usage.

Any and all feedback is greatly appreciated, and I will try to provide more in depth information if requested. Thank you!

[William5]

@Eli
Welcome!
If you can get a guesstimate for how high the trees are in your area you can have the Mimosa Design tool calculate that into the Path Profile view. (Under “Link Settings” and “Ground Level Buffer”) The Mimosa design tool will also allow for calculating an amount of foliage that is blocking (at least in the PTMP portion).

As far as cost for performance, it kinda depends on how obstructed the shot is, at that distance the C5c will work, but I would lean towards the B5 just so you can get experience with Mimosa’s Backhaul Line, and you will get GPS as long as you do not use the B5 Light. A nice side benefit is you have a spare radio if you need it elsewhere in your system. That all said, if you only want to climb a tower once for the next 5 years, the B5 is probably your radio.

The only benefit the C5c is going to give you is going to be in the cost department, plenty of people are using C5c radios around here for PTP links, and report ~50-100 Mbps, but I don’t know if anyone has reported on a link as long as what you are setting up.

[Eli]

Thanks for the reponse.

My understanding was that the ground level buffer was applied to the entire length of the link, which in my scenario is nowhere near the case of actual tree presence. I have a small patch of woods on my property that I am close to being able to shoot over, and could fairly easily have a 20 ft. path through by topping a couple trees. The only other concern is about 100-200 ft. of a woods patch mid link that might have some tree tops in the fresnel zone. I guess my concern is whether either of these potential obstructions are significant enough to keep me from completing the link? And are there any benefits in using the B5c radios that would allow them to work when the C5c would not?

Does the fresnel zone need to be completely unobstructed for the link to operate consistently? If not, what level of obstruction is tolerable?

Just trying to get a grasp on whether or not this link is feasible with potential small obstructions, or if I should scrap the whole idea.

Last question; In the B5 scenario, you infer that I would only need a single radio to complete my link. I assumed that either option was PTP. What would you use downstream of a B5 if not another B5?

[William5]

I just recommended it because it would tell you if there were any points that would be of concern, your Fresnel Zone should be pretty tiny nearby the radios, it only gets larger when you get further away from the two.

As far as mid link obstructions, it depends on how much obstruction there is. 10% is not much of a problem, IMHO and from what we have seen, but +50% will probably cause link issues. (The area in between is a grey area where everyone has differing opinions and experiences) So I would get a guesstimate of the height of the trees and plug it in the buffer that way you know what you are looking at. The Link Planner tool can give you some reasonable estimates on what you will see, you just need to make sure you have reasonable settings for the link plugged in. (Power, Interference, Obstructions, etc.)

We have found that Mimosa Equipment is more Porsche and less Jeep, give it a clear path and it will rocket away. Not that it does not do well on poor links, it does about as good as anybody we have used so far, just the spectrum of difference is much larger. (They do better then other people on good links and you feel the weaker link more because you are used to the better performance)

Without seeing the link for myself, not too terribly interested because I really don’t care to know the GPS location of where people live, I can’t say yay or nay definitively. If you are already using C5c equipment in your network and not B5 equipment then I would say “throw up a C5c and see what you get” they are cheep and if the link does not work then you are not left sitting with expensive equipment. Otherwise, the B5 is much cooler, will perform better in all cases, has GPS Sync and has the 2.4 management radio which will let you align with your phone on the tower.

To your last question, I apologize for my lack of clarity. Yes you will need 2 of either the C5c or the B5 line. (B5 to B5, B5 lite to B5 lite etc) (Pretty sure you can’t mix and match, but that would be a question for @David)