28-GHz Channel Measurements and Modeling for Suburban Environments

Abstract

This paper presents millimeter wave propagation measurements at 28 GHz for a typical suburban environment using a 400-megachip-per-second custom-designed broadband sliding correlator channel sounder and highly directional 22-dBi (15 • half-power beamwidth) horn antennas. With a 23-dBm transmitter installed at a height of 27 m to emulate a microcell deployment, the receiver obtained more than 5000 power delay profiles over distances from 80 m to 1000 m at 50 individuals sites and on two pedestrian paths. The resulting basic transmission losses were compared with predictions of the over-rooftop model in recommendation ITU-R P.1411-9. Our analysis reveals that the traditional channel modeling approach may be insufficient to deal with the varying site-specific propagations of millimeter waves in suburban environments. For line-of-sight measurements, the path loss exponents obtained for the close-in (CI) free space reference distance model and the alpha-beta-gamma (ABG) model are 2.00 and 2.81, respectively, which are close to the recommended sitegeneral value of 2.29. The root mean square errors (RMSEs) for these two reference models are 9.93 dB and 9.70 dB, respectively, which are slightly lower than that for the ITU site-general model (10.34 dB). For non-line-of-sight measurements, both reference models, with the resulting path loss exponents of 2.50 for the CI model and 1.12 for the ABG model, outperformed the site-specific ITU model by around 14 dB RMSE.

Measurement-Based 5G Millimeter-Wave Propagation Characterization in Vegetated Suburban Macrocell Environments

“…As shown in Figs. 2 and 3, the minimum directional path loss may even decrease with increasing distance for certain special cases, such as the Route 2 OLoS case in the villa district environment and the OLoS case with the TX-RX separation range of [201,283] m in the industrial park environment, as well as the similar results reported in [5], [21]. This observation implies a strong influence of propagation areas that are sparsely populated with a finite number of scatterers in the characterization of mmWave large-scale fading channels.…”

“…In urban microcell and macrocell environments (e.g., urban very-high-rise, urban high-rise, and urban low-rise environments), channel characteristics have been widely investigated in the two 5G mmWave candidate bands (i.e., 28 GHz and 39 GHz) [5]- [8]. However, there is a dearth of research focusing on the underlying measurement-based characterization of mmWave channels in suburban macrocell environments except for [19]- [21]. To predict transmission losses for suburban line-of-sight (LoS) and NLoS scenarios at 28 GHz, directional measured data were collected to fit the close-in (CI) free-space reference distance model and the alpha-beta-gamma (ABG) model, where the antenna pattern was deembedded based on precisely reconstructing the geometric relationship between the antennas [21], [22].…”

“…However, there is a dearth of research focusing on the underlying measurement-based characterization of mmWave channels in suburban macrocell environments except for [19]- [21]. To predict transmission losses for suburban line-of-sight (LoS) and NLoS scenarios at 28 GHz, directional measured data were collected to fit the close-in (CI) free-space reference distance model and the alpha-beta-gamma (ABG) model, where the antenna pattern was deembedded based on precisely reconstructing the geometric relationship between the antennas [21], [22]. In [20], the preliminary results (e.g., path loss, shadowing and delay spread) for statistically modeling 28 GHz channel in residential suburban cellular scenario were presented based on a double-directional measurement campaign.…”

Propagation Modeling Through Foliage in a Coniferous Forest at 28 GHz

“…The measurement system in our previous work [4] was utilized. The receiver (RX), with a chip rate of 399.95 megachips per second, was installed in a backpack and powered by a lithium-ion polymer battery for portability purposes.…”

Millimeter Wave Path Loss Modeling for 5G Communications Using Deep Learning With Dilated Convolution and Attention

“…These equations are variations of the Friis free-space path loss model, and a few parameters are required [19]. Empirical methods such as the close-in free space reference distance (CI) model and alpha-beta-gamma (ABG) model [4] are relatively easy to handle when the measurement data are given. However, the parameters of empirical models should be determined based on the measurement data collected in a specific scenario and thus their prediction accuracy may decrease when they are applied to a scenario that differs considerably from the measured scenario.…”