number required for pilot tones the excess sub carriers or a sub set of them may be entirely suppressed instead the suppression of oob emissions at the frequency of the atsc pilot carrier increases a protection margin for the prevention of interference to atsc tv receivers this protection margin can be used to allow operation of ofdm communications devices e g portable devices base stations in closer proximity to a tv receiver or at higher power to increase the range as data rate increases in importance as compared to proximity and or range the number of un modulated carriers may be reduced and the suppression and protection margin are accordingly reduced a controller within the ofdm communication device may determine the number and location of sub carriers that are un modulated or suppressed the ofdm un modulated sub carrier selection was defined with specific reference to limiting interference to the atsc pilot carrier but is in no way limited thereto rather the selection of un modulated ofdm sub carriers could be used to minimize interference between other wireless devices with increased vulnerability to interference at specific frequencies e g wman wlan wpan although the disclosure has been illustrated by reference.