parabolic grid coverage area

RouterOS Wireless Networking
1

Hi all ;
i have some questions regarding the coverage area of the wireless antenna like the parabolic grid .
i was reading in the manual that the angle for the grid is :

  • Horizontal beamwidth is 10 dgree .
  • Vertical beamwidth is 14 dgree .

so i start counting by using triangle equations to check what is the elevation of the signal when i put the grid about 25 - 30 meters above the ground on my tower and on that level will the signal reach the clients’ antennas which mostly about 10 meters from the ground .
the results showing that the signal elevation will be too big and i do not have to tilt down the grid , but in fact when i orient a grid toward a client and ask them to read the signal level at their side i found they have it with low DB !!!
parabolic grid.pdf (104 KB)
another thing , if i orient the grid toward client A i found that he have signal lower than client B who will be a side of the grid direction ??? :confused: :confused:

i attached a file with here , can we use the triangle eguation for this purpose or not ? and how to know if the signal will reach the client without tilting the grid down ? .
also if anyone could explain deeply the pattern graph attached also here to understand the signal behaiviour and could reduce the noise and get better performance .
images4.jpg
with best regards to all

2

That would appear to be an offset parabolic.
In which case, when properly oriented appears to be aimed into the ground.
Because of the offset nature the signal is reflected down to the feed.

Also Side lobes can be quite significant with an offset style, especially on the reflected angle.
So if you have it aimed to the sky, as I believe you probably do, you will see significantly higher signals on your side lobes, due to the nature of these dishes.

3

Hi tgrand ;
Thanks for your fast reply .
first the antenna is not a parabolic dish althouth i wish to use them in the next future .
i am talking about 2.4 Ghz grid antenna with 24 dbi .
could you give us more details about the side loop signals and other related issues .
with best regards .

4

Hi ;
no comments on this ??? :confused: :open_mouth:

with best regards .