ABSTRACT
Massive multiple-input multiple-output (MIMO) has been attracted and widely considered as a key technology for future wireless networks. To maximize the gain of massive MIMO, the accurate channel state information at the transmitter (CSIT) is essentially required. Pilot contamination and pilot overhead are the major limiting factors to the system performance. Therefore, channel estimation is quite challenging for massive MIMO cellular networks. Currently, channel estimation schemes utilize both the channel sparsity and its low-rank property in the beamspace and antenna domains, respectively. This chapter provides current research efforts in channel estimation techniques for the MIMO-OFDM system.
