Asymmetrical 30degee LTU Rocket Design - Downtilt


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What is the best way to determine how down tilt affects the 30degree horn pattern?  We have a 200ft tower that we are looking at putting a 30degree horn on and want to make sure we are maximizing its potential for a group of homes between 1-2 miles from the base of the tower.    Radio will be a UBNT LTU Rocket on the horn. And likely LTU-LR stations.   

I played around a bit with the link calc 2.0 but it is acting like I'm putting ltu rockets as every cpe which isn't going to be the case.  It also never seems to show me an actual color gradient of coverage. 

I've mapped it in the UISP Design center and have it set as a 30deg 20db custom antenna but understand it won't have the exact pattern of your horn and is more symmetrical in design.   I believe that the azimuth of 289 would be correct, but don't understand how the downtilt plays into the design.   I'm also trying to understand what the practical distances from this antenna and horn would be. 

I've attached what the UISP tool believes the signal would look like.  How far off from this would I expect an asymmetric horn to be, and would this be the right horn for this use case?  

One of the concerns is that houses 7 and 8 are on the very edges.  If I were to pick one over the other, it would be trying to keep 7.

Thanks for any and all help with this.  

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Hey, sorry we missed this.  

For the gradient coverage on the link calculator, make sure you selected PTMP mode.  And it can take a minute or two for it to shade depending on range and other factors.  Attached are two quick calcs I did estimating the AP location, probably needs some tweaking.  I mapped out the far end of 10x in the middle and then on the far sides near the edges and that ends up being roughly 3 miles in the center and 1.7 miles right on the edges.  The coverage looks gnarly with the terrain, so I ran another one with the same height cpe as ap just to take that out of the equation in the other file.  Keep in mind the edges roll off pretty quick but it's not a direct laser like cut where a few feet over drops signal.  I think you are good to keep 7 and 8 but play around in the calc a bit more and see what it says.  

At these distances and AP heights, leave 0 downtilt.  It's a wider elevation cut by far than what you're used to working with on sectors, so the signal gets to the ground real fast.  I played around with some downtilt values and your far reaches of 10x start dropping pretty quick after more than a couple of degrees.  So stick with 0.  Most of the time you end up with 0 unless the AP is on a mountain and you're shooting down into valley or your nearest subs are right on the base of the tower.  

I used LTU Rocket as a client with 26dbi from LR gain as it's a RX estimate so I doesn't matter a ton.  Also only the LTU RF specs are out there and no more info is shared so we can't populate the details per CPE like we can with other brands.  RXL should be right on with the AP power set as is in the pic, and mod rate should be close.  

Hopefully that clears things up.  If not then email me direct caleb [at} and can explain further. 

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