Cyclostationarity-inducing transmission for OFDM-based spectrum sharing systems

This paper introduces cyclostationarity-inducing transmission methods for identifying OFDM-based signals in spectrum-shared environments. Specifically, the OFDM signal is configured before transmission such that its cyclic autocorrelation function (CAF) has certain peaks at preselected cycle frequencies and time lags. By choosing specific peak patterns for each transmitter, the cognitive receivers can obtain the necessary information for coordinating spectrum sharing environments. We investigate several improvements to cyclostationarity-inducing transmission such as an overhead reduction method and flexible peak induction method. The newly-proposed flexible peak induction method extends the position of the CAF peaks into not only the cycle frequency domain but also the lag parameter domain. The signal identification performance is evaluated based on computer simulation and testbed experiments.