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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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Programmable Radio Environments for Smart Spaces
Smart spaces, such as smart homes and smart offices, are common Internet of Things (IoT) scenarios for building automation with networked sensors. In this paper, we suggest a different notion of smart spaces, where the radio environment is programmable to achieve desirable link quality within the space. We envision deploying low-cost devices embedded in the walls of a building to passively reflect or actively transmit radio signals. This is a significant departure from typical approaches to optimizing endpoint radios and individual links to improve performance. In contrast to previous work combating or leveraging per-link multipath fading, we actively reconfigure the multipath propagation. We sketch design and implementation directions for such a programmable radio environment, highlighting the computational and operational challenges our architecture faces. Preliminary experiments demonstrate the efficacy of using passive elements to change the wireless channel, shifting frequency "nulls" by nine Wi-Fi subcarriers, changing the 2 x 2 MIMO channel condition number by 1.5 dB, and attenuating or enhancing signal strength by up to 26 dB.
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- Award ID(s):
- 1763309
- PAR ID:
- 10177062
- Date Published:
- Journal Name:
- HotNets-XVI
- Page Range / eLocation ID:
- 36 to 42
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1145/3152434.3152456
