The Guard Band in LTE has defined to be 10% of available bandwidth. As known, LTE technology offers several available channels bandwidth:
-
1.4 MHz
-
3 MHz
-
5 MHz
-
10 MHz
-
15 MHz
-
20 MHz
This means that different channels bandwidth will have different Guard Band, as shown in the following Table.
Furthermore, it must to be clear in your mind that LTE protocol is defined to be an OFDMA System and channels are multiplexed in Resource Elements (RE) and Resource Block (RB).
Table 1: Bandwidth, RB number, Useful Band and Guard Band for LTE
From Table. 1 it should be clear that only in the case of 1,4 MHz bandwidth the guard band does not correspond to 10%. In fact, it is equal to 320 KHz or 22.85%
Therefore, following it is possible to find an explanation about this difference between channel 1,4 MHz and the others.
Kindly see:
Best regards