Disclosed is a method of transmitting data over a plurality of wireless frequency bands between a transmitter and a receiver during one of a plurality of rounds, the method comprising: computing a target spacing in time between a start time of transmission in a first band and a start time of transmission in a second band dependent on a first data rate in the one round and in the first band; commencing transmitting, by the transmitter, a first frame of data over the first band at the first data rate; waiting for the computed target spacing to elapse, and then commencing transmitting, by the transmitter, a second frame of data over the second hand at a second data rate.