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guess.who
2009-06-27, 04:55 AM
Can come one elaborate the why and when Mechanical Tilting is used and Where, when and why is electrical tilt used to control coverage... ie the basic and fundamental differnence in usage of electrical and mechanical tilt....

The other thing that i wanted to ask was....why do we use different kind of MW antenna in comparison to radio antennas....when and why radio antennas are used and when and why MW radios are used.....

Please Help....i really need this info urgent
BR

guess.who
2009-06-28, 01:09 AM
Please can someone help...i really need this information urgent...

venom
2009-06-28, 01:52 AM
Can come one elaborate the why and when Mechanical Tilting is used and Where, when and why is electrical tilt used to control coverage... ie the basic and fundamental differnence in usage of electrical and mechanical tilt....

The other thing that i wanted to ask was....why do we use different kind of MW antenna in comparison to radio antennas....when and why radio antennas are used and when and why MW radios are used.....

Please Help....i really need this info urgent
BR

To understand it, u first need to know the difference between electrical and mechanical tilting.

Electrical Tilt: We all know that our antenna radiates electromagnetic waves (Radio Waves) and to do so we need to pass the current through plates. Now our antenna is composed of many plates through which we need to pass the current. The tilting of those plates is called electrical tilt. The advantages of this is that we suppress the backlobe as well we downtilt. See the attached picture.

Mechanical Tilt: If u want the antenna itself to be downtilt then u have to do so by changing the tilt of a mount. It is called mechanical tilt. The disadvantage of using it is that the backlobe increase with the downtilt. See the attached Picture.

I have made those pictures myself, this is only for ur understanding, the actual picture is different, we have vertical and horizontal beams.

guess.who
2009-06-28, 03:10 AM
Brilliant brilliant Sir....Thaaaaaaaaaaaaaaaaaaaaaanks a lot for the greaaaaaaaat effort....can u please also answer the radio and MW antenna question ??


Thanks once again

venom
2009-06-28, 03:29 AM
Brilliant brilliant Sir....Thaaaaaaaaaaaaaaaaaaaaaanks a lot for the greaaaaaaaat effort....can u please also answer the radio and MW antenna question ??


Thanks once again

Microwaves are also electromagnetic waves and if u talk generally then radio waves are the sub category of it Microwaves. In telecommunication, the name changes with its application, microwaves are used to have the long distance communication whereas radio waves are used to have short distance communication as well as long distance. The power transmitted by a microwave antenna is gr8er than the radio antenna.

In GSM, Radio Antenna are used with the different frequency than Microwave Antenna. Microwave antennas are having parabolic antenna (DISH) which needs to have the LOS with the other Microwave antenna. It is made in such a way to exhibit the very desirable highly directional response for both receiving and transmitting. In Telecommunication Microwaves are used for the BTS Transmission (BTS-BTS Communication).

In radio antenna, we have RF bands defined. (900/1800/2100). It can be directional antenna or omni-directional. We use it for the communication of (BTS-MS). The frequencies are different than microwave. The transmitted signal by a radio antenna exhibts reflections and even if the user is not at the LOS then the communication is possible. Whereas if the microwave link is failed, the BTS Communication gets interrupted straight away. It means microwave links are more sensitive than radio.

I hope it helps, further reading will help you to understand it in more detail, thanks

guess.who
2009-06-28, 03:59 AM
Sir

I cannot Thanks u enough

RF engineer
2009-06-28, 04:15 AM
Dear
all above explanation is right and one more thing is that MW radiate high power as compared to RF signal in case if want antenna to have MW frequency you need more power to create this energy and this means more cost for the operator and second thing the governments not using this frequency any more let say in military so they can used and get money instead to be free band i donot know if you see some news that some operators want to use some frequency in range of TV .
BR
RF

da_manole
2009-06-28, 04:49 AM
Can come one elaborate the why and when Mechanical Tilting is used and Where, when and why is electrical tilt used to control coverage... ie the basic and fundamental differnence in usage of electrical and mechanical tilt....

The other thing that i wanted to ask was....why do we use different kind of MW antenna in comparison to radio antennas....when and why radio antennas are used and when and why MW radios are used.....

Please Help....i really need this info urgent
BR

If you need more information about this let me know

guess.who
2009-06-28, 06:08 AM
Wow ......Thanksss sooo sooo much to both RF Engineer and da_manole....very useful info...

BR