And this will be done using 900 Mhz RS232 wireless serial radios. They top out at 9600 baud.
You've got 11 months to get better radios.
But the receiver cannot read it and stuff it back into 6 sets of integers.
At 9600 baud, it has an eternity to parse and convert the data.
We need to see some code to see why you are having problems.