The concepts relate to radio channel utilization. One example can identify a channel for communicating data. The channel can include a set of sub-channels that span from a lower frequency adjacent channel to a higher frequency adjacent channel. This example can encode the data on the set of sub-channels of the channel in a manner so that an individual sub-channel that is closer to either the lower frequency adjacent channel or the higher frequency adjacent channel than another individual sub-channel has a smaller amplitude than an amplitude of the another individual sub-channel.