A new achievability scheme for downlink multicell processing with finite backhaul capacity

In the scenario of downlink multicell processing, for the case of two base stations and two mobile users, by viewing the problem as a multiple access diamond channel with two destinations, we propose an achievability scheme that combines both the achievability of correlated codewords into the multiple access channel and Marton's achievability for the general broadcast channel. Compared with previously known schemes, our scheme focuses more on exploiting the gain of correlation between the transmitted signals of the base stations. We demonstrate through examples that our proposed scheme outperforms known achievability schemes when the capacities of the backhaul links are in the medium range.