Why not use different tilt for each ant

[mojiiiiii]

I have a sector(Alpha) on top of a hill with traffic at the foot of the hill and traffic another 5 miles from it.

Alpha sector ant configuration:

ANT1 Tilt: 9
ANT2 Tilt: 5
ANT3 Tilt: 5

What's the problem with doing multiple tilt?
I know this might not be best practice; however it seems logical to cover to area with this setup.

I would like to hear your feedback. Thanks!

[Optimal]

Interesting !!! Waiting for expert.


mojiiiiii, how about the performance of this cell ???

[mojiiiiii]

Interesting !!! Waiting for expert.


mojiiiiii, how about the performance of this cell ???


i dont try that still.
any way,i think that it affect (KPI,traffic,C/I.etc etc),right?

[dacoder]

I don't think there's problem in doing that since the site is placed at top of the hill. If there isn't much tilt then the coverage might overshoot to unwanted places causing interference there and poor service quality.

[tsiz]

I have a sector(Alpha) on top of a hill with traffic at the foot of the hill and traffic another 5 miles from it.

Alpha sector ant configuration:

ANT1 Tilt: 9
ANT2 Tilt: 5
ANT3 Tilt: 5

What's the problem with doing multiple tilt?
I know this might not be best practice; however it seems logical to cover to area with this setup.

I would like to hear your feedback. Thanks!

Why are you using 3 antennas for the same sector? Is this because 2 of them have the same band and the other is in a different band?

presuming the latter-

I assume that 5 and 5 degress fall under one technology (3G or 2G) and the other antenna at 9 is a another technology.

It also depends on the band you are using. Maybe the 5 degrees is with 850 and the 9 degress is with 1900. 850 has more penetration and needs more containment so the tilts on them are set to 9.

If you are using all the 3 for the same technology say 2G I would say that this is not correct and all the tilts should match because if you have BCCH broadcasting on antenna with tilts set to 9 degrees, it handsover to the TCH channel on the antenna with tilt set to 5 degress causing drop calls on TCH because the BCCH and the TCH footprints do not match.

[Optimal]

Some ideas by using multi-beam antenna. It can improve capacity by minimizing soft handover.

Argus Product Update July 2010.ppt (http://www.mediafire.com/?exsa65xzuecxxvi)

[rishi]

are all of them with one sector???

or else with different sectotrs of bts

because if it is of same sector one sector will take bcch and transfer it to other woth tch which can cause high call drop due to different tilt

[haq_enam]

I have a sector(Alpha) on top of a hill with traffic at the foot of the hill and traffic another 5 miles from it.

Alpha sector ant configuration:

ANT1 Tilt: 9
ANT2 Tilt: 5
ANT3 Tilt: 5

What's the problem with doing multiple tilt?
I know this might not be best practice; however it seems logical to cover to area with this setup.

I would like to hear your feedback. Thanks!


Multiple tilt mean Mechanical and electrical?? If it is....u can do it but u have to think backloop as weel. Doing too much tilting top of the hill cause interference in other places...u could lost ur coverage in ur targeted areas as well....if location is 5 km away from site i think tilt is need to be adjust more.....depands on site height, direction of the antennas,type of antennaes...

[kevin_h811]

Hi Mojiiii,

Multi Antenna and Multi-tilt will not solve any problem since it will cause problem itself...This is what we call split sectors, but not advisable.Very small coverage,noisy, poor call set-up, etc..

Just use one antenna and use your Optimization skills...

Regards//

[wirelessboy]

Hi mojiiii,

give us mor infos about your config:

you use ant 1, 2 and 3.
Tell us the frequency and service (2G,3G) of each antenna.
Are the antenna x-polazed (means you use polarization diversity in the cells) or do you have linear polarized (with a spatial rx diversity.)?

I think antenna 1 must be a x-pol .... for ant2 and 3 we dont know ... can be 2 sectors with x-pol or 1 with spatial diversity.

tell me so I try to help you

cu the wirelessboy

[s52d]

I have a sector(Alpha) on top of a hill with traffic at the foot of the hill and traffic another 5 miles from it.

Alpha sector ant configuration:

ANT1 Tilt: 9
ANT2 Tilt: 5
ANT3 Tilt: 5

What's the problem with doing multiple tilt?
I know this might not be best practice; however it seems logical to cover to area with this setup.

I would like to hear your feedback. Thanks!

Hi!
Without knowing technology and configuration: Yes, it works.
I've seen two cases in use in GSM:
- BCCH+TCH on one antenna, second antenna only for diversity.
Second antena tilted a bit to minimize uplink interference.
make sure BCCH+TCH is not moved to second ant during some upgrade/maintenance.

Second case, in fact two sectors in hilly area, both with same direction (very simmilar),
one uptilt, one downtilt.

One more case I've seen in the mountains: antenna mounted horizontally.
So, it has 65 degrees vertical lobe (to cover mountain acrooss the valley), and 8 degrees horizontal lobe.

BR
s52d