Aalto University School of Electrical Engineering Advances ...Aalto University School of Electrical...
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Aalto University School of Electrical Engineering Advances in Site-Specific Radio Propagation Studies Katsuyuki Haneda Aalto University School of Electrical Engineering ISART 2018 panel “Driving Forward: Advances in Propagation Modeling” July 25 2018 1
Transcript of Aalto University School of Electrical Engineering Advances ...Aalto University School of Electrical...
A alto U niversitySchool of E lectricalEngineering
Advances in Site-Specific Radio Propagation Studies
Katsuyuki HanedaAalto University School of Electrical Engineering
ISART 2018 panel “Driving Forward: Advances in Propagation Modeling”
July 25 2018
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Points of Interest
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2. Antenna-human-channel interaction
1. Point cloud for site-specific propagation simulations
Tiny things can make difference! The interaction can diminish coverage!
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Point Cloud for Site-Specific Propagation Simulations
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High Frequency Channel Simulations Using Optical Measurements of the Environment
Open square in Helsinki3 million points
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High Frequency Channel Simulations• Points in the point cloud
produce– Specular reflections– Diffuse scattering– Attenuation loss due to shadowing
• Material parameters (e.g. permittivity)taken from ITU-R P.2040 or can be optimized as variables
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Specular + Diffuse = Overall channel
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Street canyon @ Aalto University
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What We Know• Wave scattering is as strong
at millimeter-wave as legacy cellular frequencies, i.e., below-6GHz
6Koivumäki et al., PIMRC ’18.
Wall from which we studied scattering
Antenna pointing angle [o]
Antenna pointing angle [o]
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Mul
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Specular onlyPathloss = 63 dB
Specular + diffuse scatteringPathloss = 60 dB
Study at 28 GHz
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What We Do Not Know Properly• Implication of scattering on small-cell link performance
– Example: four co-channel links operating in a small room
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Rx3 Rx4
Rx1 Rx2
Tx4
Tx3
Tx2 Tx1
Haneda et al., VTC-Spring 2015.
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Antenna aperture size [λ2]
Cha
nnel
cap
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s/H
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TR11TR22TR33TR44
Dashed: w/ co-channel intf.Solid: w/o co-channel intf.
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What We Do Not Know Adequately• Feasibility of indoor coverage by outdoor base stations
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window blind shut
window blind not in use
Details are presented in my poster of this conference.
Example: Measurement-based study at 14 GHz
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Antenna-Human-Channel Interaction
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Antenna-Human Interaction• Also more noticeable self-body blockage effects
10Simulations at 28 GHz
Electric field distribution
Simulationmodel
Radiationpattern
A patch antenna on a mobile phone-sized ground plane
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Small-Cell Coverage Analysis
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• Example: Helsinki airport check-in hall (terminal 2)
J. Jarvelainen et al., IEEE TAP, 2016 and J. Vehmas et al., VTC Fall2016.
Base station
Coverage map with idealistic omni-directional mobile antennas at 60 GHz
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• Cellular coverage under intervention of mobile users
What We Do Not Know Adequately
Red: omni-pathloss w/o bodyBlack: pathloss of mobile w/body and finger
Mobile antenna:uniform linear array
Haneda et al., VTC Spring 2018.
