Joint DL and UL Channel Estimation for Millimeter Wave MIMO Systems Using Tensor Modeling

Figure 2

Proposed closed-loop and multifrequency-based training framework. The DL and UL channels are jointly estimated. The BS first transmits pilot sequences. The MSs encode the received pilots and then feed them back to the BS. The BS jointly estimates the DL and UL channels. The text in blue refer to DL communication, while the text in red refer to UL communication.