Electrical tilt + Mechnical tilt for Wimax network

[engrsaeed]

We are optimizing Mobile WiMAX network.

Sites are mostly 600 meters away from each other and heights of sites are different in urban area its between 35 to 55 meters.we have only 3 channels and we have 3 sector per site. we are 65 degree beamwidth antenna....

on 50 meter height if we use 15 mechanical tilt its covering in horizontal direction and interfering with others sites near by and if electrical tilt is used only 10 degree it will lower the coverage and may be overshoot...

Please i need expert advice to tilt the antennas...

Can we use electrical + mechanical tilt(some professional said it is not advisable)...

The on sites which are higher what will be advisable....

Please if someone have documents regarding this....

[arian.jumaa]

if the distance between the sites is about 600 meter why you are using (35 to 55) meter height?, use (20 to 25)meter with mechanical tilt(2) and electrical tilt (2) it will cover with out over shooting and making interference to other sites

[engrsaeed]

thanks arian for your reply...

Regarding the height its only available in dense urban area with all tall buildings so in our current situation what you will advise..........

Anyone else have some solution.......

[dimooon11]

Can we use electrical + mechanical tilt(some professional said it is not advisable)...

Why not? Go ahead and choose electrical + mechanical tilt ratio depending on every site location and surrounding morphology/terrain.
I personally believe you're not going to perfectly control coverage with 55m height sites, be ready for some flaws.

[Philippe]

For high sites, can't you lower the antenna? on building walls or lower position on the pylon.

Electrical tilt is preferable to mechanical tilt for antenna pattern reason. Please find attached a good whitepaper from Andrew.

http://docs.commscope.com/Public/ele...erformance.pdf