Date Added: Oct 2010
Both Long Term Evolution (LTE) and WiMAX (802.16) 4th Generation wireless systems (4G) utilize Orthogonal Frequency Division Multiplexing (OFDM) on the down-link. The advantages of OFDM over other wireless communication techniques are well known. These technologies will become more ubiquitous as time goes on. Here a study is presented of the potential for covert communication within an OFDM waveform. Most OFDM standards call for unused sub-channels for channel spacing, synchronization of transmitter and receiver and to mitigate poor channel response.