Hi Dhiman,
DC block, as its name implies, is used to block the DC signal that may be flowing into the main signal. In optical comminications, DC blocking can be used to suppress beat noise or for other purposes that lead to better SNR at the receiver. You can refer to the below paper where it has been used for such a purpose, for example:
IQ compensation is used for IQ imbalance in the system, which might occur due to some mismatch in the way in-phase signal and quadrature signal are formed separately (the Q channel has to have an exact 90 degree delay,. Otherwise there is a mismatch). There are also many papers on “IQ imbalance compensation”, but I suggest first you visit wikipedia to know more about the concept if you are interested:
https://en.wikipedia.org/wiki/IQ_imbalance
Unfortunately, I don’t know about resampling, which may be upsampling and/or downsampling. I hope the component help section provides more information on each of these in the future versions.
Regards