Methods and apparatus for providing an adaptive beamforming antenna for OFDM-based communication systems. In one embodiment, a method includes forming a matrix (A) of cyclic prefix values and a matrix (B) of tail values from an orthogonal frequency division multiplexed (OFDM) symbol, and forming a summation matrix (S) and a difference matrix (D) from the matrix A and the matrix B. The method also includes multiplying a beamformer preset matrix (W) with the matrix S and the matrix D to determine a matrix (P) and a matrix (Q), and determining a beam identifier from the P and Q matrices.