Peak Power Reduction in Closed-Loop MIMO-OFDM Systems via Mode Reservation

This letter studies peak-to-average power ratio (PAPR) reduction for orthogonal frequency-division multiplexing (OFDM) signals in eigenbeamformed multiple antenna systems. The weak eigenmodes abandoned by the waterfilling allocation are intentionally filled in order to offset signal peaks in the time domain.Numerical results indicate that this method can significantly increase the efficiency of peak power constrained systems with no modification of the receiver required.