Reweighted base station activation in a green downlink MISO network with long-term stability guarantee

In modern wireless networks, dynamically optimizing the association between base stations (BSs) and users is a promising solution for performance improvement. However, a frequently changing BS-user association introduces heavy burden for network management. In this paper, we seek for balancing the flexibility and stability of the BS-user association in a green downlink MISO network. In addition to minimizing the transmit power and controlling the number of active BSs, we further consider reducing the users´ switching frequency among BSs. This problem is a nonlinear mixed-integer program, and challenging to solve. As a compromise, we see for some efficient approximate solution to it by reformulating it as a convex sparse problem. An efficient algorithm is then developed to enhance the sparse solution, based on the iterative reweighted l₁ technique. The effectiveness of the proposed algorithm was validated by numerical simulations.