Joint beam adaptation in 60GHz interference channel via sequential stochastic approximation

The best beam directions for Q coexisted 60GHz radio systems are jointly determined to maximize the sum rate. Capturing the directional characteristic of 60GHz indoor interference channel, a joint discrete optimization problem is properly established with the objective function evaluated from the noisy channel estimates. In addition to the conventional exhaustive search (ES) method, we propose a simulation based sequential stochastic approximation (SSA) algorithm with segmented indicator to solve the problem in an adaptive way. Although only the sub-optimal solution can be guaranteed in practice, the proposed algorithms are demonstrated to be more efficient and practical to implement than beam search in brute force, especially in dense network. Also, they exhibit good flexibility and feasibility for different usages in tradeoff between performance and complexity.