A successive carrier-transmission model for narrow-band subliminal channels

The capacity of a narrow-band subliminal channel can be proportional to log 2 n, and then its upper bound is log 2 n where n is the number of input values a subliminal transmitter tried. These results are obtained, provided that only the single carrier is transmitted. In this paper, we consider a practical model, a successive carrier-transmission model, where carriers are transmitted one after another successively, and then only n 0 input values are tried between each carrier transmission. This model is more natural because such situation happens frequently in a real life. Then, we estimate the achievable channel capacity of a narrow-band subliminal channel under this model. It is clear that the channel capacity can also be proportional to log 2 n 0 bit/carrier under this model, but under this model more information can be transmitted on each carrier. Some concrete schemes are proposed to realize the previous statement, and then their channel capacities are compared.