dlaw

Antenna alignment – 30-degree sector

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We have started to deploy the new 30-degree sectors on all of our new tower builds and my tower crew is complaining about how difficult it is to get the antennas lined up. Do you have any secrets as to how to get them aligned to the right azimuth?   We have used the Air prism HD-90 in the past and you only have to align 4 antennas making it pretty easy. Do you have any tools or techniques that might help in this process?

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@dlaw,

Thanks for posting and sorry for the problems.  When building out new towers with horns it can be slightly challenging because of the sharp drop off on beam angle.  What I would suggest is using 40deg horns or maybe 2x 30deg and 1x 40deg for your 90deg coverage area.  40deg horns only have about 2db less gain then the 30's so you will not notice a difference in your links. The extra 10deg of coverage would allow you to overlap a bit and close any dead zones between Horns.

We are looking into ways to perhaps mark and angle or have a add on tool that will help visualize the coverage area.  Please let us know if you try the 40's and how they work.  We would love to see pictures of your install and if you could share your CPE type and distances of links with signal, that would be great!

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Take the cover off the front and the radio off the back. You can look through the port to gauge the target zone. You can proof in google earth when planning the site. 

Twist port alignment scope/tool.

The tool could be your cell phone camera in a twist port that holds the phones camera in the right place (or a GoPro). And an app for PC or other device that allows you to look at the target coverage area in google earth to make a target picture. Then when you are on the tower with the twist port alignment tool it will show you the google earth picture as an overlay or simple cross hair or ring. The app could have a selection to choose the horn you are using.

Or maybe a simple tube with an eyepiece, it could slide in and out to the correct field of view to match the horn. I think a clip on spotting scope would be easier to manage on the tower. Maybe clipping to the back/smallest ring where the set screws are. Or even something that clips to the front.

Just my thoughts, Sorry for rambling.  

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On 11/16/2016 at 3:19 PM, Tasos said:

@dlaw,

Thanks for posting and sorry for the problems.  When building out new towers with horns it can be slightly challenging because of the sharp drop off on beam angle.  What I would suggest is using 40deg horns or maybe 2x 30deg and 1x 40deg for your 90deg coverage area.  40deg horns only have about 2db less gain then the 30's so you will not notice a difference in your links. The extra 10deg of coverage would allow you to overlap a bit and close any dead zones between Horns.

We are looking into ways to perhaps mark and angle or have a add on tool that will help visualize the coverage area.  Please let us know if you try the 40's and how they work.  We would love to see pictures of your install and if you could share your CPE type and distances of links with signal, that would be great!

Can you explain the gain of the 30 degree horn at the 3dbi and 6dbi sides? I have 3 of the 30 degree horns and I'm wondering if I should go to the 40 degree when doing 360 degree coverage.

I guess what I want to know, are we getting 18dbi at the edge of the 20deg mark or 15dbi? and would the 30 degree edge only be 12dbi? If this is true then what is the 5 and 10 degree points? Is the 18dbi in the center at only 4 degrees?

Edited by jober

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Yes, you got it right. At 21 degree - it is defined symmetrically so it means 10.5° from the center on both sides - the signal will be 3dB less than the maximum so the antenna has 15.5dBi gain there. At 30° (15° from the center on both sides) the signal is 6dB weaker comparing to the maximum so the gain of the antenna is 12.5dBi. The maximum gain of 18.5dBi is always defined at 0°. At 5° the gain of the antenna is 17.7dBi and at 10° the antenna has 17.2dBi gain.

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Thanks for feedback. We will definitely look into this in order to provide you with an easy tool that will help you to aim our horn antennas. 

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Maybe an add on for the ignitenet scope (http://www.ignitenet.com/products/metrolinq-scope/). Many operators start to user their 60Ghz product line more and more too. 

A clip that sits around the smallest ring of any horn (they are all the same dia?) where the scope then gets attached too. RF Elemenents is great in making such add-on devices for 3rd party products....

The target cross in the scope should be pointed towards a landmark that you'd calculated in Google Earth first. (Take a copy of the picture with ya!)

All that is needed is that the scope indeed is H+V parallel with the centre of the horn...

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@dlaw,

I love how you have done the setup on your tower and I really am liking the brackets that attach to the tower.  I am going to do my first TP setup soon and would like to do something similar to how you setup your tower.  Where might I find the brackets like what you are using in the pics above?

Thanks

Dan

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22 minutes ago, aardvarkglory said:

@dlaw,

I love how you have done the setup on your tower and I really am liking the brackets that attach to the tower.  I am going to do my first TP setup soon and would like to do something similar to how you setup your tower.  Where might I find the brackets like what you are using in the pics above?

Thanks

Dan

 

http://www.mccowntech.com/

https://www.streakwave.com/itemdesc.asp?ic=M-TOW-TRIPLE&eq=&Tp=&o1=0

 

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