TCC means Transmit Cohorent Combining, this is an Ericsson feature that provide addition 2dB gain on transmitting.
47dBm + 2dBm = 49dBm
but main disadvantage of this feature is that it reduces capacity by half. 2TRX act as 1TRX, 4TRX act as 2TRX.
thsi feature is mainly used on Highway sites.
Hope this will help.
Consultant some Doc on TCC