Variations on Information Embedding in Multiple Access and Broadcast Channels Shivaprasad Kotagiri Student Member, IEEE, and

Information embedding (IE) is the transmission of information within a host signal subject to a distortion constraint. There are two types of embedding methods, namely irreversible IE and reversible IE, depending upon whether or not the host, as well as the message, is recovered at the decoder. In irreversible IE, only the embedded message is recovered at the decoder, and in reversible IE, both the message and the host are recovered at the decoder. This paper considers combinations of irreversible and reversible IE in multiple access channels (MAC) and physically degraded broadcast channels (BC). This paper first considers MAC IE in which separate encoders embed their messages into their host signals subject to distortion constraints. The embedded signals from the two encoders are transmitted to a single decoder across a MAC. This paper study the capacity region in three cases: A) no host recovery at the decoder, B) lossless recovery of one host at the decoder, and C) lossless recovery of both hosts at the decoder. For the cases A and B, inner bounds on the respective capacity regions are developed. For the case C, inner and outer bounds on the capacity region are developed and the capacity region is obtained if the hosts are independent. This paper also considers BC IE in which two messages intended for separate decoders are embedded into a given host sequence by a single encoder subject to a distortion constraint. This paper study the capacity region for degraded BC in four cases: A ′ ) lossless recovery of the host sequence at neither of the decoders, B ′ ) lossless recovery of the host sequence at only the better decoder, C ′ ) lossles