Rate-Optimal Coding Design in Joint Transfer of Energy and Information

In this letter, performance optimization for information transfer in a binary and noiseless one-way information transmission system is investigated from the perspective of information source design (e.g., coding scheme) while considering the amount of energy that can be transferred. We propose a variable-length coding scheme and address two problems to optimize the information rate: (1) to determine a proper number of channel use (or maximal codeword length) while a fixed amount of energy is to be transferred; (2) to determine a proper amount of energy to be transferred while information is required to be transferred within a fixed number of channel use. The two problems are both formulated as integer fractional programming problems and the optimal solutions are derived with in-depth analysis. For both problems, numerical results show that the proposed variable-length coding scheme with the optimal amount of energy to be transferred or optimal number of channel use outperforms the coding strategy in an existing work.