Network coding with nested lattice for interference coordination of relay heterogeneous networks

In heterogeneous networks consisting of relay nodes and multiple antennas, beam-forming optimization is an enabling technology yielding high throughputs. Network coding not only transforms interferences into effective signals, but also provides more freedom of macro-relay coordination. This paper presents a network coding interference coordination scheme over lattice-forward multiple-input multiple-output channels. At first, we will derive the achievable rate with nested lattice codes, and then maximize the sum-rate of cooperating regions through iterative algorithm and Lagrange multiplier method. For comparisons, capacity of several conventional schemes are also provided. Numerical results validate the proposed scheme.