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How UE knows what bandwidth is used and which is the center frequency to identify center subcarrier ?

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InLTE there are different bandwidths like 1.4,Mhz, 3Mhz, 5Mhz, 10Mhz etc.... so how UE knows it and its cnter subcarrier?

posted Jan 21, 2015 by Shivaraj Kenche

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On behalf of Bart (https://www.facebook.com/groups/LTE.Professionals ) -
The eNB is sending this data. This is one of the basic info the eNB sends.
I'm not a Radio guy but I'm guessing this will be send in a common/shared channel.
commented Jan 21, 2015 by Salil Agrawal

1 Answer

0 votes
  1. UE sweeps through all supported band one by one in a order. Sweeping is done in a steps of 100KHz (Channel raster for LTE)
  2. Once some energy is detected, using PSS and SSS UE performs time and Frequency Synchronisation. At this stage UE now clearly knows the center frequency
  3. PSS, SSS and PBCH are all of 72 subcarriers (1.08MHz) corresponds to smallest supported bandwidth. Once UE reads PBCH one of the parameter is Bandwidth of operation. After this step UE now clearly knows the bandwidths of operation (1.4/3/5/10/15/20 MHz).

I hope it helps?

answer Jan 21, 2015 by Salil Agrawal
If it is for 700 to 720MHz with bandwidth 20MHz , so where do UE finds the DC subcarrier?
commented Jan 22, 2015 by anonymous
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