Measurement-Based Massive MIMO Polarimetric Channel Characterization in Outdoor Environment

Abstract

This paper introduces a measurement campaign to investigate the characteristics of massive multiple-input multiple-output (MIMO) channels in both line-of-sight (LoS) and obstructed LoS suburban outdoor environments. The measurements are conducted at the center frequency of 3.5 GHz with a bandwidth of 160 MHz. The transmitter is equipped with a 4 × 8 planar patch antenna array and the receiver is equipped with a 4 × 8 cylindrical patch antenna array. Each patch consists of two antenna ports which have main polarizations of +45 • and −45 • , respectively, resulting in a total of 64 × 64 sub-channels. We examined the influence of different polarization combinations on channel characteristics such as power delay profile (PDP), K-factor and delay spread for both LoS and obstructed LoS scenarios. Results show that the characteristics are more dependent on the Rx antennas rather than the Tx antennas. When the Rx antennas are facing the Tx antenna array, the received power is higher, the K-factor is lower and the delay spread is lower in cross-polarization cases with respect to the co-polarization ones in general. When the Rx antennas are back-facing the Tx antenna array, lower powers, higher K-factors and higher delay spreads can be observed in cross-polarization cases with respect to the co-polarization cases. In conclusion, the polarimetric influence on the channel characteristics depends on the antenna structure as well as the environment. INDEX TERMS Channel characterization, delay spread, K-factor, massive MIMO, power delay profile.

Channel Measurement for Multiple Frequency Bands in Subway Tunnel Scenario

“…All multipath signal propagation paths in the tunnel environment can be detected perfectly. e structure of the Tx and Rx antenna is very similar to that used in [24,25], as shown in Figure 4. e Tx is equipped with a 2×8 uniform rectangular antenna patch array.…”

Measurements and Characteristics Analysis of 6G Ultra-Massive MIMO Wireless Channels With Different Antenna Configurations and Scenarios

“…The LCR is larger and the AFD is smaller for Route 2 than those for Route 4 when the reference level is in the range of -10 dB to 10 dB. The KF can be calculated by moment method in [45]. Fig.…”

Measurement-based Double-Directional Polarimetric Characterization of Outdoor Massive MIMO Propagation Channels at 3.5GHz

“…In this paper, we continue with our earlier contributions [8], [9], with a focus on the polarization and angular domain characteristics for the massive MIMO channel. Since the transmitter (Tx) and receiver (Rx) antenna elements have both +45 • and −45 • polarizations, we choose Tx and Rx antenna pairs with the same or different polarization combinations, such as Tx +45 • with Rx +45 • , Tx +45 • with Rx −45 • , Tx −45 • with Rx +45 • , and Tx −45 • with Rx −45 • , to analyze the channel polarimetric characteristics.…”

“…However, when the Tx and Rx antennas are copolarized, the power spreads more, being distributed for all azimuth angles at the main elevation of 75 • . The explanation for the effects of different polarizations is given in our previous contribution [8]. Due to the same antenna structure, when the Tx and Rx antennas are pointing to each other, the transmitted −45 • polarized signal matches the +45 • polarized Rx antenna port.…”