On the Characterization of Beam Misalignment in Outdoor-to-Indoor 60 GHz mmWave Channel

In this paper, the measurement data of an outdoor-to-indoor channel at 60 GHz for various orientations of the receiver is analyzed. We comment on the variation of the received line-of-sight (LOS) component power and delay spread with respect to the misalignment angle and suggest the existence of clusters which map to nearby buildings acting as scatterers. We propose a method to randomly generate the tapped delay line (TDL) filter model of the channel for any orientation of the receiver. We divide the range of misalignment angle into sectors of 5 degrees each and analyzed the similarity between the TDL models of each sector. The analysis enabled us to group the sectors into two categories: (A) [0,10) degrees and (B) [10,25) degrees. The TDL model is used to determine the bit error rate (BER) curve. The BER results are reported for BPSK modulation at 8 Gbps datarate. It is seen that when the misalignment angle exceeds 10 degrees, the BER floor goes up significantly, causing a BER increase of almost two orders. It can also be related to the lack of the LOS component in category (B), as the main-lobe of the receiver is steered further away from LOS.