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We propose a novel analytical framework for evaluating the coverage performance of a millimeter wave (mmWave) cellular network where idle user equipments (UEs) act as relays. In this network, the base station (BS) adopts either the direct mode to transmit to the destination UE, or the relay mode if the direct mode fails, where the BS transmits to the relay UE and then the relay UE transmits to the destination UE. To address the drastic rotational movements of destination UEs in practice, we propose to adopt selection combining at destination UEs. New expression is derived for the signal-to-interference-plus-noise ratio (SINR) coverage probability of the network. Using numerical results, we first demonstrate the accuracy of our new expression. Then we show that ignoring spatial correlation, which has been commonly adopted in the literature, leads to severe over estimation of the SINR coverage probability. Furthermore, we show that introducing relays into a mmWave cellular network vastly improves the coverage performance. In addition, we show that the optimal BS density maximizing the SINR coverage probability can be determined by using our analysis.
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Reconfigurable and Adaptive Coupled Relay Resonator Platform for a Moving Receiver
Linearly arranged passive relay resonators have been shown to be able to extend wireless power transfer range. However, extending this relay concept to a 2-D planar array with the intention to cover a larger area presents challenges; naïvely constructing a plane of tessellated relays results in a poor efficiency of power transfer due to complex interactions between relays as the number of relays increases [1]. In this paper, we implement the first electronically reconfigurable relay transmitter system, which allows efficient transfer in large relay arrangements and can track a moving receiver across its coverage area. We propose a receiver tracking method and algorithm which can scan the entire coverage area over 2000 times per second and, once found, can configure the relay array to efficiently deliver power to the receiver.
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- Award ID(s):
- 1305072
- PAR ID:
- 10114062
- Date Published:
- Journal Name:
- 2019 International Workshop on Antenna Technology (iWAT)
- Page Range / eLocation ID:
- 182 to 185
- 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/10.1109/IWAT.2019.8730619
