Grc and wlan based ofdm

i want to make a system bassd on ofdm modulation wich is wlan 802.11g or
802.11a so i want to ask if it’s possible to do this in gnu radio
companion (base band system, transmitter ,channel and receiver) Â with
all details such as scrambling encoding interleaving modulation ;Â so i
ask if any one can give me list of blocks that i need specially in
creating ofdm symbols and inserting pilots subcarriers because i think
that ofdm mod block wich exist dosn’t support pilots subcarriers