Channel Estimation Using Subspace Decomposition for SC-FDMA Systems

In SC-FDMA systems the bit error rate (BER) is very sensitive to channel estimation errors. We propose the use of blind (or semi-blind) subspace decomposition to estimate the channel frequency responses between the transmitter and the multiple antennas of the receiver in the uplink of a 4G system employing SC-FDMA. The proposed subspace- based channel estimation technique requires very little overhead in terms of pilot symbols dedicated to channel estimation. Furthermore, we show through simulations that, when applied to SC-FDMA, it can provide a BER performance comparable to a system with perfect channel estimates.