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nabil el haddani
2009-10-20, 12:16 AM
Hi guys,

Can anyone explain me why the TCH drop calls could be higher when antenna diversity is disabled????

Br,

Nab

RF engineer
2009-10-20, 12:28 AM
Hi guys,

Can anyone explain me why the TCH drop calls could be higher when antenna diversity is disabled????

Br,

Nab
As you know diversity main function is to improve the signal quality and the reliability of radio link( multipath fading) so if you disabled the receiver would not track the signal from other direction so you have time delay, phase shift and signal attenuation so there will be call drop increase.
BR
RF

Processor
2009-10-21, 01:10 AM
....on point

paengbasti
2009-10-21, 12:38 PM
Hi guys,

Can anyone explain me why the TCH drop calls could be higher when antenna diversity is disabled????

Br,

Nab


To simplify further...

Antenna diversity, also known as space diversity, is one of several wireless diversity schemes that use two or more antennas (Polarisation Diversity in GSM) to improve the quality and reliability of a wireless link. In urban and indoor environments, there is no clear LOS between transmitter and receiver. Instead the signal is reflected along multiple paths before it is received. The reflected signal can introduce phase shifts, time delays, attenuations, and even distortions that can destructively interfere with one another at the aperture of the receiving antenna. Antenna diversity is especially effective at mitigating these multipath situations. Each antenna will experience a different interference environment. Thus, if one antenna is experiencing a deep fade, it is likely that another has a sufficient signal. Collectively such a system can provide a robust link.

Thus, having antenna diversity will greatly reduce/minimise dropped calls. Moreover, there are vendor-specific features that further reduces DC.