In this study, results of wideband dual polarised measurements conducted in indoor environments including office, factory, corridor and computer foyer, using state-of-the-art 2×2 multiple-input-multiple-output frequency modulated continuous wave-based channel sounder, are presented. The measurements were performed in two frequency bands with 6 GHz bandwidth, centred at 54 and 70 GHz, with directional steerable ~20 dBi (18° beamwidth) horn antennas. Using twists at the transmitter and at the receiver simultaneous co-polar and cross-polar measurements were performed to quantify the polarisation effects on channel parameters such as angular spread, delay spread and path loss. The results show that the co-polarised radio links experienced lower angular spread and delay spread compared with the cross-polarised links. For co-polarised links, the estimated synthesised omnidirectional path loss exponent was found to be in the range of 1.5-2 (close-in model) and 0.9-1.9 (log-distance model) in the respective environments. In individual scenarios, the median cross-polarisation ratio was found to be within 11.7-14.4 and 7.5-17.6 dB at 54 and 70 GHz, respectively.
- radio propagation