Transmitting and receiving alternatively with same USRP

Hi everyone

I am trying to write an application (to implement a TDMA MAC) in which a
node alternatively transmits and receives using the GMSK code. Basically
want to implement the following functionality

  1. After I receive a packet, I want to be able to shut down or stall the
    receive side of the graph
  2. Now transmit a packet and after its done, re-enable the receive side.

I tried to use a mechanism similar to already included in the
distribution, but I cannot get the one to one ratio which I want, i.e.
sometimes the transmit path doesnt get scheduled for a while since the
receive path blocks are active and are receiving packets. Has anyone
something similar before? Any pointers would be greatly appreciated.