The Experts below are selected from a list of 297 Experts worldwide ranked by ideXlab platform
Syed A Jafar - One of the best experts on this subject based on the ideXlab platform.
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degrees of freedom of wireless networks with relays feedback coOperation and full Duplex Operation
IEEE Transactions on Information Theory, 2009Co-Authors: Viveck R Cadambe, Syed A JafarAbstract:We find the degrees of freedom of a network with S source nodes, R relay nodes, and D destination nodes, with random time-varying/frequency-selective channel coefficients and global channel knowledge at all nodes. We allow full-Duplex Operation at all nodes, as well as causal noise-free feedback of all received signals to all source and relay nodes. An outer bound to the capacity region of this network is obtained. Combining the outer bound with previous interference alignment based achievability results, we conclude that the techniques of relays, feedback, full-Duplex Operation and noisy coOperation do not increase the degrees of freedom of interference and X networks. As a second contribution, we show that for a network with K full-Duplex nodes and K(K-1) independent messages with one message from every node to each of the other K-1 nodes, the total degrees of freedom are bounded above and below by [( K(K-1))/( (2K-2))] and [( K(K-1))/( (2K-3))], respectively.
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Capacity of Wireless Networks within o(log(SNR)) - the Impact of Relays, Feedback, CoOperation and Full-Duplex Operation
arXiv: Information Theory, 2008Co-Authors: Viveck R Cadambe, Syed A JafarAbstract:Recent work has characterized the sum capacity of time-varying/frequency-selective wireless interference networks and $X$ networks within $o(\log({SNR}))$, i.e., with an accuracy approaching 100% at high SNR (signal to noise power ratio). In this paper, we seek similar capacity characterizations for wireless networks with relays, feedback, full Duplex Operation, and transmitter/receiver coOperation through noisy channels. First, we consider a network with $S$ source nodes, $R$ relay nodes and $D$ destination nodes with random time-varying/frequency-selective channel coefficients and global channel knowledge at all nodes. We allow full-Duplex Operation at all nodes, as well as causal noise-free feedback of all received signals to all source and relay nodes. The sum capacity of this network is characterized as $\frac{SD}{S+D-1}\log({SNR})+o(\log({SNR}))$. The implication of the result is that the capacity benefits of relays, causal feedback, transmitter/receiver coOperation through physical channels and full Duplex Operation become a negligible fraction of the network capacity at high SNR. Some exceptions to this result are also pointed out in the paper. Second, we consider a network with $K$ full Duplex nodes with an independent message from every node to every other node in the network. We find that the sum capacity of this network is bounded below by $\frac{K(K-1)}{2K-2}+o(\log({SNR}))$ and bounded above by $\frac{K(K-1)}{2K-3}+o(\log({SNR}))$.
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capacity of wireless networks within o log snr the impact of relays feedback coOperation and full Duplex Operation
arXiv: Information Theory, 2008Co-Authors: Viveck R Cadambe, Syed A JafarAbstract:Recent work has characterized the sum capacity of time-varying/frequency-selective wireless interference networks and $X$ networks within $o(\log({SNR}))$, i.e., with an accuracy approaching 100% at high SNR (signal to noise power ratio). In this paper, we seek similar capacity characterizations for wireless networks with relays, feedback, full Duplex Operation, and transmitter/receiver coOperation through noisy channels. First, we consider a network with $S$ source nodes, $R$ relay nodes and $D$ destination nodes with random time-varying/frequency-selective channel coefficients and global channel knowledge at all nodes. We allow full-Duplex Operation at all nodes, as well as causal noise-free feedback of all received signals to all source and relay nodes. The sum capacity of this network is characterized as $\frac{SD}{S+D-1}\log({SNR})+o(\log({SNR}))$. The implication of the result is that the capacity benefits of relays, causal feedback, transmitter/receiver coOperation through physical channels and full Duplex Operation become a negligible fraction of the network capacity at high SNR. Some exceptions to this result are also pointed out in the paper. Second, we consider a network with $K$ full Duplex nodes with an independent message from every node to every other node in the network. We find that the sum capacity of this network is bounded below by $\frac{K(K-1)}{2K-2}+o(\log({SNR}))$ and bounded above by $\frac{K(K-1)}{2K-3}+o(\log({SNR}))$.
D. Robein - One of the best experts on this subject based on the ideXlab platform.
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Versatile in-line transceiver chip operating in two full-Duplex modes at 1.3 and 1.55 μm
IEEE Photonics Technology Letters, 2000Co-Authors: H. Nakajima, A. Leroy, J. Charil, D. RobeinAbstract:We describe a transceiver chip which can perform full-Duplex Operation alternatively in the 1.3 /spl mu/m (TX)/1.5 /spl mu/m (RX) or 1.5 /spl mu/m (TX)/1.3 /spl mu/m (RX) mode. A full Duplex sensitivity of -28.4 dBm is reported for the transceiver mode emitting at 1.55 /spl mu/m and receiving at 1.3 /spl mu/m.
H. Nakajima - One of the best experts on this subject based on the ideXlab platform.
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Versatile in-line transceiver chip operating in two full-Duplex modes at 1.3 and 1.55 μm
IEEE Photonics Technology Letters, 2000Co-Authors: H. Nakajima, A. Leroy, J. Charil, D. RobeinAbstract:We describe a transceiver chip which can perform full-Duplex Operation alternatively in the 1.3 /spl mu/m (TX)/1.5 /spl mu/m (RX) or 1.5 /spl mu/m (TX)/1.3 /spl mu/m (RX) mode. A full Duplex sensitivity of -28.4 dBm is reported for the transceiver mode emitting at 1.55 /spl mu/m and receiving at 1.3 /spl mu/m.
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-31 dBm sensitivity of a monolithic transmit-receive-device over wide temperature range
OFC IOOC . Technical Digest. Optical Fiber Communication Conference 1999 and the International Conference on Integrated Optics and Optical Fiber Commu, 1999Co-Authors: F. Mallecot, D. Carpentier, H. Nakajima, A. Leroy, A. Plais, C. Chaumont, E. Derouin, F. Gaborit, J. Jacquet, F. DoukhanAbstract:High system performances (-31 dBm), over wide temperature range, were demonstrated by a monolithic in-line transmit-receive-device, designed for single fibre, bi-directional transmission in full-Duplex Operation at 155 Mbit/s.
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Full-Duplex performance assessment of in-line transceivers emitting at 1.3 μm and receiving at 1.55 μm
IEEE Photonics Technology Letters, 1996Co-Authors: H. Nakajima, A. Leroy, J. CharilAbstract:Starting from the signal-to-noise ratio formula for in-line transceivers, we evaluate the receiver performance in full-Duplex Operation. We show theoretically and experimentally two methods to obtain a system compatible sensitivity. Full-Duplex sensitivities of -23.9 dBm and -19.1 dBm are demonstrated at 68 Mb/s and 196 Mb/s, respectively.
Bang Chul Jung - One of the best experts on this subject based on the ideXlab platform.
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uav assisted cooperative downlink noma with virtual full Duplex Operation
International Conference on Ubiquitous and Future Networks, 2019Co-Authors: Jeong Seon Yeom, Youngbin Kim, Bang Chul JungAbstract:In this paper, we investigate an unmanned aerial vehicle (UAV)-assisted downlink cellular network where there exist a single base station (BS), two mobile stations (MSs), and multiple UAV relay stations (RSs) between the BS and MSs. We assume that there exist no direct communication links from the BS to the MSs due to unexpected blockages from obstacles or disasters and the BS is assumed to exploit a non-orthogonal multiple access (NOMA) technique for support two MSs. We propose a novel spectrally-efficient successive relaying technique, also known as virtual full-Duplex Operation, which selects a single UAV-RS among randomly deployed UAVs to send a superimposed NOMA signal for two MSs. It is shown that the proposed cooperative NOMA technique with virtual full-Duplex Operation outperforms the conventional cooperative NOMA technique with half-Duplex Operation in terms of outage probability.
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ICUFN - UAV-Assisted Cooperative Downlink NOMA with Virtual Full-Duplex Operation
2019 Eleventh International Conference on Ubiquitous and Future Networks (ICUFN), 2019Co-Authors: Jeong Seon Yeom, Youngbin Kim, Bang Chul JungAbstract:In this paper, we investigate an unmanned aerial vehicle (UAV)-assisted downlink cellular network where there exist a single base station (BS), two mobile stations (MSs), and multiple UAV relay stations (RSs) between the BS and MSs. We assume that there exist no direct communication links from the BS to the MSs due to unexpected blockages from obstacles or disasters and the BS is assumed to exploit a non-orthogonal multiple access (NOMA) technique for support two MSs. We propose a novel spectrally-efficient successive relaying technique, also known as virtual full-Duplex Operation, which selects a single UAV-RS among randomly deployed UAVs to send a superimposed NOMA signal for two MSs. It is shown that the proposed cooperative NOMA technique with virtual full-Duplex Operation outperforms the conventional cooperative NOMA technique with half-Duplex Operation in terms of outage probability.
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Opportunistic Network Decoupling With Virtual Full-Duplex Operation in Multi-Source Interfering Relay Networks
IEEE Transactions on Mobile Computing, 2017Co-Authors: Won-yong Shin, Bang Chul Jung, Vien V. Mai, Hyun Jong YangAbstract:We introduce a new achievability scheme, termed opportunistic network decoupling (OND), operating in virtual full-Duplex mode. In the scheme, a novel relay scheduling strategy is utilized in the $K\times N\times K$ channel with interfering relays, consisting of $K$ source--destination pairs and $N$ half-Duplex relays in-between them. A subset of relays using alternate relaying is opportunistically selected in terms of producing the minimum total interference level, thereby resulting in network decoupling. As our main result, it is shown that under a certain relay scaling condition, the OND protocol achieves $K$ degrees of freedom even in the presence of interfering links among relays. Numerical evaluation is also shown to validate the performance of the proposed OND. Our protocol basically operates in a fully distributed fashion along with local channel state information, thereby resulting in a relatively easy implementation.
Noboru Ishihara - One of the best experts on this subject based on the ideXlab platform.
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a 1 3 1 55 spl mu m wavelength division multiplexing optical module using a planar lightwave circuit for full Duplex Operation
Journal of Lightwave Technology, 2000Co-Authors: Toshikazu Hashimoto, T Kurosaki, Masahiro Yanagisawa, Y Suzuki, Y Akahori, Yasuyuki Inoue, Y Tohmori, Kuniharu Kato, Y Yamada, Noboru IshiharaAbstract:We developed a hybrid integrated optical module for 1.3/1.55-/spl mu/m wavelength-division multiplexing (WDM) full-Duplex Operation. The optical circuit was designed to suppress the optical and electrical crosstalk using a wavelength division multiplexing filter, and an optical crosstalk of -43 dB and an electrical crosstalk of -105 dB were achieved with a separation between the transmitter laser diode and the receiver photodiode of more than 9 mm. We used the optical circuit design to fabricate an optical module with a bare chip preamplifier in a package. This module exhibited a full Duplex Operation of 156 Mbit/s with a minimum sensitivity of -35.2 dBm at a bit error rate of 10/sup -10/.
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Full Duplex 1300/1550-nm-WDM optical transceiver modules for ATM-PON systems using PLC-hybrid-integration and CMOS IC technologies
24th European Conference on Optical Communication. ECOC '98 (IEEE Cat. No.98TH8398), 1Co-Authors: Takeshi Kurosaki, Masahiro Yanagisawa, Y Tohmori, Noboru Ishihara, T. Hashimoto, Yasuhiro Suzuki, Hideaki Kimura, Masanori Nakamura, Ka. Kato, Yoshihiro KawaguchiAbstract:The optical transceivers using a PLC-optical-hybrid-integrated module and CMOS front-end ICs for asynchronous transfer mode/passive optical network (ATM-PON) systems are realized. Under full Duplex Operation at 156 Mb/s, receiver sensitivity of less than -34 dBm and dynamic range of over 28 dB are achieved, which satisfies FSAN-class B/C specification.
