A Channel Independent Precoding for MIMO-OFDM Systems with Insufficient Cyclic Prefix

In this paper, a channel independent precoding for MIMO-OFDM systems of n_t transmit and n_r receive antennas with insufficient cyclic prefix (CP) is proposed. By empolying the interference alignment (IA) idea, we show that our proposed channel independent precoding scheme can eliminate the interblock interference (IBI) caused by the insufficient CP with a higher bandwidth efficiency than the conventional zero-padding or adding a sufficient CP when n_r ≤ n_t. It is also shown that when n_r >; n_t, the IBI can be eliminated without any zero-padding or adding CP or precoding when the OFDM block length is not small.