Adaptive beam tracking for interference alignment in time-varying MIMO interference channels: Conjugate gradient approach

Based on a linear formulation to interference alignment, an adaptive algorithm for interference-aligning beam tracking in time-varying MIMO interference channels is proposed. It is shown that obtaining the interference-aligning beam vector is equivalent to minimizing a certain Rayleigh quotient, and the conjugate gradient approach is adopted to construct an adaptive algorithm. The convergence and stability of the proposed algorithm are established in static channel case, and numerical results show that the proposed algorithm performs well compared with other existing methods with much less complexity.