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View Full Version : two antennas for single sector single band



rishi
2011-01-24, 04:21 AM
does anyone has a detail information regarding same sector having two antennas of same band and same carrier??

i have heard like it is for capacity and one is used for tch and other is used for bcch is it true???

if yes can u please give me details of its use

tremalnike
2011-01-24, 05:32 AM
Two V-pol antennas in same GSM sector is used to ensure space diversity.

Two X-pol antennas in same GSM sector is used to avoid 3dB combining loss , when you have more than two TRX per cell.

dekili
2011-01-24, 09:24 AM
Using multiple antennas per sector can only provide you benefits on the physical layer and nothing on the upper layers. It means that you can get benefits in space diversity or to compensate combinaer loss, again throughdiversity scheme (in essence).

DCA
2011-01-24, 01:27 PM
@tremalnike
and extention of the sectorbeamwidth for specific area's for capacity problems

rishi
2011-01-24, 05:10 PM
then why it is recommended to keep same configuration for tilts for both the antennas on the high capacity or it is found mostly on high capacity zone

dekili
2011-01-24, 10:50 PM
then why it is recommended to keep same configuration for tilts for both the antennas on the high capacity or it is found mostly on high capacity zone

Keeping same tilt is related to interefernce issue that can arise if you have two antennas on a small distance. You will find such configuration in high capacity areas, which are usualy lacking space for placing equipment and antennas, so you have to take care about antenna separation and interference...