Low Complexity Estimation of Frequency Selective Channels for the LTE-A Uplink

3GPP LTE-A uplink channel estimation is based on pilot symbols. For the support of MIMO transmissions, a special reference symbol structure was standardized to perform MIMO channel estimation without excessive overhead. We propose a low complexity channel estimation method in the frequency domain based on correlation that exploits the orthogonal structure of the reference symbols to mitigate inter-layer interference. Further, we introduce a smoothing method to deal with the interference that leads to improved performance at low signal to noise ratio.