Generic selectors
Exact matches only
Search in title
Search in content

# Electrical Tilt Formula

Viewing 15 posts - 1 through 15 (of 29 total)
• Author
Posts
Mohit
Guest

Hi All…

One of my friend has recently gone through an interview…and the interviewer asked him two questions…

1) wat is the formula for calulating/ deciding electrical tilt for a site.

2) how many TCH are required during a Confrence call..

Pls do reply if somebody have any idea regarding these above question…

Regards..
Mohit..

pix
Guest

1> geometrical calcula : depending on height of antenna, expected cell range and vertical aperture of the antenna, one can compute the required tilt in order to locate the upper “-3dB” point onto the cell range.
f(H, CR and VHPBW) –> tilt
the formula uses “tan” function… i let you find it by yourself 🙂

2> only one TCH per user.

Mohit
Guest

Thanks Pix…

But can u explain this formula a little more…i mean with an example…

Regards..
Mohit

pix
Guest

Mohit,

i hope you didn’t kill yourself trying to find the formula, huh.

cell range = Height BTS / (tangent(tilt – VHPBW/2))

example : height = 30m
VHPBW = 8 degrees
tilt = 6 degrees

–> cell range = 30/tan(radians(6 – 8/2)) = 859 meters.

Mohit
Guest

Many Many thanks Pix…
🙂

MKT
Guest

Pix..

How will you find the 3 dB point from BTS?

Does the formula takes into account the BTS Tx Pwr Max?

Regards

MKT

pix
Guest

the 3dB upper point is taken into account in the formula (–> VHPBW/2)

the BTS power does not matter in this formula. What matters is how far you want to locate your “3dB upper point” (=cell range). The BTS power will then give you the “intensity” of the coverage within this cell range.

regards
pix

MKT
Guest

Pix

what is VHPBW?

Regards

pix
Guest

vertical half power beam width… it is the vertical “aperture” of the antenna. You can see it on the antenna specifications. Usually around 8 degrees.

Nitin Tomar
Guest

What is the significant of Vertical beamwidth in coverage???

Pix
Guest

Nitin, isn’t it explained just one post below ?

baig
Guest

Is the tilt in the formula got from sum of electrical and mechanical tilt or its just the electrical tilt? how does mechanical tilt affect the formula

Pix
Guest

In the formula, you should use the sum of electrical tilt + mechanical tilt.

Ahsan
Guest

I really acknowledge ur effort regarding helping other optimizers and learners..

Well it means that we have to take effective tilts into account.

Also i wanted to know the individual effect of mechanical and electrical tilt.

Well as i have experienced.. mechanical tilts adds backlobes.. question is Y.?

Pix
Guest

Hello,

Mechanical tilt : increase downtilt in front, but since you’re tilting the whole antenna, you see that the backlobe will get uptilted, yes? ,

Electrical tilt: all directions around the antenna are tilted down, like when you’re closing an umbrella : all sides are getting down at the same time.

Viewing 15 posts - 1 through 15 (of 29 total)
`<a href="" title="" rel="" target=""> <blockquote cite=""> <code> <pre class=""> <em> <strong> <del datetime="" cite=""> <ins datetime="" cite=""> <ul> <ol start=""> <li> <img src="" border="" alt="" height="" width=""> `