Question regarding packet transmission

Hi all,

I have two transmit antenna set up and would like both
antennas to transmit different packets at the same
time.

Eg, Packet A to be transmitted by antenna 0 and Packet
B to be transmitted by antenna 1 these two packets
must be transmitted at the same time.

How do i do this? I tried to manually turn on and off
the daugther boards connecting the antennas but the
recieved super imposed signal are incomplete.

Regards,
Willy