interference is cancelled from a baseband signal by synthesizing interference from estimated symbols in interfering subchannels . the estimated symbols are hard - coded , soft weighted , or zeroed , depending on the value of an estimated pre - processed signal - to - interference - and - noise ratio in each subchannel in order to maximize a postprocessed sinr . the estimated pre - processed sinr is obtained from averages of estimated symbol energies and estimated noise variances , or from related statistical procedures .