Optimization of a two-color reuse scheme in multi-beam high throughput satellite systems

In this letter, we propose a two-color reuse scheme in the forward link of multi-beam high throughput satellite systems, where dual-polarization is utilized to provide an additional dimension to isolate severe inter-beam interference. This scheme is optimized through formulating a nonconvex optimization problem with respect to precoding design to maximize system sum rate, taking into account the intense interference among beams using the same polarization. Then a path-following algorithm is proposed for its solution. Afterwards, we further seek a low-complexity precoding design and simplify the original precoding optimization problem into a power allocation one, whose problem is still non-convex and a quadratic transform algorithm is proposed to achieve its near-optimum. Extensive simulations verify that the proposed scheme exhibits improved sum rate, compared to that of the current single polarization full frequency reuse and four-color frequency reuse ones.