Semi-feedback for the binary multiplying channel

In his paper on two-way channels (TWC) Shannon (1961) derived the so-called inner and outer bound region. For a TWC without feedback the outer bound coincides with the inner bound. As a consequence, the capacity region of a TWC without feedback is equal to its inner bound. Furthermore, Shannon showed that for the binary multiplying channel (BMC) the inner and outer bound are different. Dueck (1980) also proved the existence of a TWC with feedback at one terminal (semi-feedback) for which the capacity region is in excess of its inner bound region. However, the BMC with semi-feedback was believed to have a capacity region that coincides with the inner bound region. Nevertheless, a semi-strategy has been constructed for the BMC that operates beyond the inner bound region. The semi-strategy is based on both the new message percolation technique of Schalkwijk (see Proceedings Joint Swedish-Russian International Workshop on Information Theory, vol.6, p. 87-91, Sweden, 1993) and the old bootstrapping techniqu

A 2-D weighing procedure for two-way communication

New coding schemes for the binary multiplying channel, based on a 2-D weighing procedure, are discussed

New results on a fundamental problem in network information theory

his paper is concerned with two new results on coding strategies for the binary multiplying channel. The binary multiplying channel is a two-way channel that models, for example, a wired-AND connection. The coding strategies are described as a progressive subdivision of the unit square into so-called resolution products. The first part of the paper concerns a new class of constructive coding strategies for the binary multiplying channel that achieve surprisingly high transmission rates. The second part of the paper establishes a new region of achievable rate pairs (R1,R2) for the binary multiplying channel that includes the equal rate point R=R2~0.63072 bit per transmission. A further substantial improvement of the achievable rate region by unit square division is prohibitively difficult