Sinh Le Hong Nguyen’s research while affiliated with GRÄNGES SWEDEN AB and other places

... A comparison between the 28 GHz and 140 GHz channel models for a shopping mall environment confirms the fewer multipath components at 140 GHz, but the strongest paths show a high correlation [19]. Outdoor measurements at 142 GHz, with a distance of 15 m between the antennas, show excess losses ranging from 15 dB to 30 dB for reflected paths in a street canyon [20]. ...

Reference:

Outdoor Channel Modeling at D-Band Frequencies for Future Fixed Wireless Access Applications

... The penetration loss of objects was found to increase with increase in frequency. The reflection and penetration loss of drywall and glass obtained from ray tracer calibrations at 28 and 142 GHz agrees well with the channel measurements conducted in [65]. Lower foliage loss was observed at 142 GHz compared to 73 GHz, possibly because the 142 GHz outdoor measurements were conducted in the fall of 2021, when the trees had fewer leaves, while the 73 GHz outdoor measurements were conducted in the summer of 2016. ...

Reference:

Calibration of NYURay for Ray Tracing using 28, 73, and 142 GHz Channel Measurements conducted in Indoor, Outdoor, and Factory Scenarios

... Several measurement campaigns have been undertaken to explore the propagation characteristics and establish a channel model [8] [9]. Numerous sub-THz channel measurements have been conducted across a wide range of indoor hotspot scenarios (InH), encompassing train-to-infrastructure [10], vehicular communications [11], shopping malls, airport check-in halls [12], data centers [13], motherboards [14], aircraft cabins [15], factory buildings [16], lecture rooms [17], meeting rooms [18] [19], office rooms [19], corridors [20], and indoor short-range scenarios [21] [24]. ...

Reference:

Path Loss Modeling and Environment Features Powered Prediction for Sub-THz Communication

... Such a correlation does not necessarily exist in other settings. For example, [45] reported the frequency correlation of approximately 0.4 between 4 GHz and 28 GHz in an outdoor environment; similarly, [46] revealed that the correlation between 980 MHz and 2400 MHz was 0.4 in the curved subway tunnels. Our proposed method utilizes the frequency correlation and thus may not be able to perform an accurate radio map construction in such a situation. ...

Reference:

Space-Frequency-Interpolated Radio Map

... Considering the foreseen massive number of IoT devices, UAVs are an attractive solution for energy efficiency and QoS improvements due to the enhanced coverage resulting from their high mobility and ability to hover as discussed in [13]. In fact, it is challenging to obtain Line of Sight (LOS) using terrestrial BSs in urban canyon environments [14], [15], and it is hard to envision smart cities without the assistance of UAVs [13], [16]. Furthermore, by equipping the UAVs with reconfigurable antennas [17], more degrees of freedom could be attained since it is possible to adjust the beam footprint of the UAV by means of electrical, optical, mechanical, and material change techniques to boost even more the coverage with QoS guarantees 2 . ...

Reference:

Minimization of the Worst-Case Average Energy Consumption in UAV-Assisted IoT Networks

... 2) The horizontal polarized omnidirectional antenna operated in mm-Wave bands are much more difficult to design [26] and even unavailable commercially. This is a current bottleneck for validating channel polarimetric profiles for multiple-input-multipleoutput (MIMO) over-the-air (OTA) studies in frequency range (FR2) [27], since both vertical and horizontal polarization measurements are required for channel polarimetric profile analysis [28]. 3) Omnidirectional antennas have low antenna gain which provides poor signal-to-noise ratio (SNR) and constrains the measurement range, which is a major problem for high frequency bands. ...

Reference:

Virtual Antenna Array With Directional Antennas for Millimeter-Wave Channel Characterization

... 2) Define D rr,n ∈ C N×N to denote the intermediate variable in (14) and (16). ...

Reference:

Embedded Propagation Graph Model for Reflection and Scattering and Its Millimeter-Wave Measurement-Based Evaluation

... A method proposed in [15] performs rough and quick angle estimation at a lower frequency and reuses the estimated spatial profiles for precious beam operation at high frequency, considering the high similarity of spatial profiles between low and high frequency bands. In [20], channel sounding results reported in mmMAGIC project, covering different propagation scenarios and different frequency bands in 2 to 86 GHz [21], were summarized with the focus on the statistical analysis of delay dispersion parameters. Though multi-band channel similarity can be directly observed, there is a lack of metrics to characterize the degree of it. ...

Reference:

On the Feasibility of Out-of-Band Spatial Channel Information for Millimeter-Wave Beam Search

... In addition to experiencing losses, the signal's polarization may be impacted by the different signal propagation paths within the channel, and the transmitted energy may appear with the Rx-orthogonal antenna orientation [79,80]. When the Tx and Rx antennas are co-polarized, the power received ratio (measured in dB) can identify the propagation feature as cross-polarization discrimination (XPD). ...

Reference:

Recent trends and future directions in millimeter wave massive MIMO channel characterization at 30/60/140 GHz: a review

... In general, two methods are used to measure the penetration loss (PL) of a material: anechoic chamber measurements [4], [9], [11] and on-site measurements [3], [7], [12]. Usually, in a nonreflection chamber, the effects of reflections on measurements can be eliminated, allowing more accurate measurements. ...

Reference:

Impact of the Window Penetration Loss on the Building Entry Loss from 3.5 to 24 GHz