Minimum number of packets usrp can receive?

i am using the RFX-2400 with usrp-1

i would like to know what is the minimum amount of data/ minimum number
packets that the usrp can receive
i used the benchmark_rx file and changed the default packet size to 10
bytes. by using the --from-file option and sending only 1 packet (10
of data i was unable to receive anything. only when the data was about 4
packets was i able to receive. i changed the packet size to different
but still couldn`t receive a single packet. i am transmitting at 500kb,
gmsk, and the --discontinuous option enabled. is this a limitation of
usrp or am i missing something?

secondly can anyone tell as to how many bits or bytes a single byte of
is converted to during transmission? i mean if i had 1 byte to transmit
would i get at the receiver say before the correlator.