A New Achievable Rate Region for the Cognitive Radio Channel

Abstract: Considering a general input distribution, using Gel'fand-Pinsker full binning scheme and the Han- Kobayashi (HK) jointly decoding strategy, we obtain a new achievable rate region for the cognitive radio channel (CRC) and then derive a simplified description for the region, by a combination of Cover superposition coding, binning scheme and the HK decoding technique. Our rate region (i) has an interesting interpretation, i.e., any rate in the region, as expected, has generally three additional terms in comparison with the KH region for the interference channel (IC): one term due to the input correlation, the other term due to binning scheme and the third term due to the interference dependent on the inputs, (ii) is really a generalization of the HK region for the IC to the CRC by the use of binning scheme, and as a result of this generalization we see that different versions of our region for the CRC are reduced to different versions of the previous results for the IC, and (iii) is a generalized and improved version of previous results ,i.g., the Devroye-Mitran-Tarokh (DMT) region.