Design and standardization of future millimeter-wave (mmWave) wireless communications systems require accurate models of wireless propagation channels. In particular, comprehensive statistical models describing the effect of human bodies moving randomly in the surrounding environment, acting as reflectors or absorbers, on the received power and delay spread are urgently needed. To enable these, new measurements campaigns are required based on channel sounders designed specifically to capture the realtime dynamics of the channel responses. This paper proposes a new methodology to enable fully dynamic measurements with a pseudonoise (PN)-sequence channel sounder by means of quasi-perfect transmitter-receiver (Tx-Rx) synchronization and suppression of probing signal effects in the post-processed channel impulse responses (CIRs). This approach allows the identification of the weak multipath components (MPCs) originated by reflections on the human body. The approach is validated by analysing CIRs collected in an indoor environment with one person moving close to the 60 GHz link. The results also demonstrate that future mmWave systems could exploit these additional MPCs and benefit from human interactions.
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Multipath Propagation Analysis for Vehicle-to-Infrastructure Communication at 60 GHz
The paper deals with an analysis of multipath propagation environment in the 60 GHz band using a pseudo-random binary sequence-based time-domain channel sounder with 8 GHz bandwidth. The main goal of this work is to analyze the multipath components (MPCs) propagation between a moving car carrying a transmitter with an omnidirectional antenna and a fixed receiver situated in a building equipped with a manually steered directional horn antenna. The paper briefly presents the time dependence of the dominant MPC magnitudes, shows the effect of the surrounding vegetation on the RMS delay spread and signal attenuation, and statistically evaluates the reflective properties of the road which creates the dominant reflected component. To understand how the MPCs propagate through the channel we measured and analyzed the power and the RMS delay spread distributions in the static environment surrounding the car using an automated measuring system with a controlled receiver antenna tracking system. We give some examples of how the MPC magnitudes change during the antenna tracking and demonstrate that a building and a few cars parked close to the measuring car create a lot of MPCs detectable by the setup with a dynamic range of about 50 dB.
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- Award ID(s):
- 1618078
- PAR ID:
- 10165863
- Date Published:
- Journal Name:
- 2019 IEEE Vehicular Networking Conference (VNC)
- Page Range / eLocation ID:
- 1 to 8
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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