- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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[IEEE 2019 International Workshop on Fiber Optics in Access Networks (FOAN) - Sarajevo, Bosnia and Herzegovina (2019.9.2-2019.9.4)] 2019 International Workshop on Fiber Optics in Access Networks (FOAN) - Overview of Wireline FTTH-Based Access Technologies in the Kosovan Telecommunication Market
摘要： This paper investigates a multi-pair two-way massive MIMO amplify-and-forward full-duplex relay (FDR) system over Ricean fading channels, where multiple pairs of full-duplex users exchange information within pair through a full-duplex relay with a very large number of antennas (M for transmission and M for reception). First, the zero-forcing reception/zero-forcing transmission and maximum-ratio combining/maximum-ratio transmission processing matrices with imperfect channel state information at the relay are presented. Then, the corresponding asymptotic expressions (in M ) of the end-to-end signal-to-interference-plus-noise ratio are derived. Finally, the asymptotic spectral ef?ciency (SE) and energy ef?ciency (EE) at the general power scaling schemes when the number of the relay antennas tends to in?nity is analyzed. Theoretical analyses and simulation results show that, when M → ∞, the effects of channel estimation error, the self-loop of each user as well as the relay, inter-user interferences, the noise at users and the relay can be eliminated, respectively, if the power scaling scheme is properly selected. Besides, the considered multi-pair two-way FDR outperforms the multi-pair two-way half-duplex relaying on SE and EE performances when M is large. Moreover, a low complexity power control scheme is proposed to optimize the SE and we analyze the impact of the number of user pairs on the SE.
关键词： power control,imperfect CSI,Ricean fading channels,full-duplex,Massive MIMO
更新于2025-09-16 10:30:52
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Quantum-Dot Intermediate-band Solar Cell used as Bottom Cell
摘要： Multiple transmitting antennas can considerably increase the downlink spectral efficiency by beamforming to multiple users at the same time. However, multiuser beamforming requires channel state information (CSI) at the transmitter, which leads to training overhead and reduces overall achievable spectral efficiency. In this paper, we propose and analyze a sequential beamforming strategy that utilizes full-duplex base station to implement downlink data transmission concurrently with CSI acquisition via in-band closed or open loop training. Our results demonstrate that full-duplex capability can improve the spectral efficiency of uni-directional traffic, by leveraging it to reduce the control overhead of CSI estimation. In moderate SNR regimes, we analytically derive tight approximations for the optimal training duration and characterize the associated respective spectral efficiency. We further characterize the enhanced multiplexing gain performance in the high SNR regime. In both regimes, the performance of the proposed full-duplex strategy is compared with the half-duplex counterpart to quantify spectral efficiency improvement. With experimental data and 3-D channel model from 3GPP, in a 1.4 MHz 8 × 8 system LTE system with the block length of 500 symbols, the proposed strategy attains a spectral efficiency improvement of 130% and 8% with closed and open loop training, respectively.
关键词： limited feedback,massive MIMO systems,multiuser MIMO systems,Wireless communication,full-duplex systems
更新于2025-09-16 10:30:52
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A 640-Gbps, 15.2344-b/s/Hz full-duplex optical fiber/wireless single-channel coherent communication system using IQM-based DP-256-QAM and DSP techniques
摘要： A full-duplex optical fiber/wireless single-channel coherent communication system is presented for high-speed data center interconnections. In-phase and quadrature modulator (IQM)-based dual polarization 256 quadrature amplitude modulation (DP-256-QAM) is implemented to achieve a maximum data rate of 640 Gbps with 40 Gbaud symbol rate for both the single-mode fiber (SMF) and free-space optics (FSO) links. Advanced digital signal processing (DSP) algorithms have been implemented at the receiver to compensate for signal impairments during propagation. The system with optical IQM and DSP algorithms can be fabricated in the form of cost-efficient integrated circuits and possess a potential spectral efficiency of 15.2344 b/s/Hz. A maximum transmission distance of 160 km and 4 km is achieved in simulation platform for the SMF and FSO links, respectively. The system performance is evaluated regarding laser linewidth requirements, optical signal-to-noise ratio tolerance, receiver sensitivity and launched optical power. This transceiver system shall be useful in high-speed long-haul communications, and the FSO system provides the same data rate to the remote areas, and last mile connections where laying of an optical fiber is not possible or cost is a major concern.
关键词： FSO,Nyquist pulse,Full-duplex,DP-256-QAM,DSP,IQM
更新于2025-09-12 10:27:22
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Freedom of Frequency: How the Quest for In-Band Full-Duplex Led to a Breakthrough in Filter Design
摘要： Wireless self-interference cancellation (SIC) was developed at Stanford University [1], [2] (and spun out as Kumu Networks) to double the spectral efficiency of radio links. SIC enables radios to transmit and receive on the same channel at the same time by canceling out the roar of the local transmitter to hear the whisper of the distant signal.
关键词： radio links,full duplex,Self-interference cancellation,SIC,spectral efficiency
更新于2025-09-11 14:15:04
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Passive Self-Interference Suppression for Single-Channel Full-Duplex Operation
摘要： Full-duplex radios have become a topic of increased interest in the wireless communications community. As part of this development, many efforts were directed to passively decrease the self-interference level at the antenna outputs. However, in many proposed solutions transmis- sion and reception occur through different prop- agation channels. This article demonstrates and quantifies the negative impact of channel differ- entiation on pivotal applications of full-duplex radio, such as cognitive radio. Antenna designs used for self-interference suppression in full-du- plex radio architectures are analyzed. In order to ensure that transmission and reception occur within the same propagation channel, the use of the envelope correlation coefficient is proposed. The article aims to first define the problem and proposes a metric to quantitatively assess full-du- plex antenna designs. This is followed by anal- ysis and discussion of representative full-duplex solutions (i.e., their antenna and passive RF feed components) proposed in the literature. Finally, it is demonstrated for the first time that passive non-magnetic self-interference suppression comes at the cost of increased losses in the structure. A theoretical upper limit for the antenna efficiency is proposed. Its consistency is verified for three representative full-duplex antenna designs that are well documented in the literature.
关键词： cognitive radio,antenna efficiency,full-duplex radio,envelope correlation coefficient,self-interference suppression
更新于2025-09-11 14:15:04
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[IEEE 2018 IEEE International Symposium on Local and Metropolitan Area Networks (LANMAN) - Washington, DC (2018.6.25-2018.6.27)] 2018 IEEE International Symposium on Local and Metropolitan Area Networks (LANMAN) - A Prototype of In-Band Full-Duplex Free-Space Optical Transceiver
摘要： Free-Space-Optical (FSO) communication has become an attractive option over Radio Frequency (RF) communication due to having broader bandwidth, unlicensed band, higher spatial reuse, and enhanced security. In-band full-duplex FSO (IBFD-FSO) transceivers ensure, in some cases enhance, these features enabling future vision of smart communication and Internet-of-Things (IoT) applications. Even though IBFD-FSO transceivers can double the network capacity theoretically, overall performance and capacity is limited by interference and optical feedback. In this paper, we present a proof-of-concept prototype of IBFD-FSO transceiver by implementing isolation technique to reduce optical feedback. We demonstrate the effectiveness of the isolation technique and performance through test-bed experiments using off-the-shelf components.
关键词： FSO,Optical Wireless,In-Band,Full-duplex
更新于2025-09-10 09:29:36
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Wideband Monostatic Co-Polarized Co-Channel Simultaneous Transmit and Receive (C-STAR) Broadside Circular Array Antenna
摘要： A novel wideband monostatic circularly co-polarized co-channel simultaneously transmit and receive (C-STAR) broadside circular array antenna with a partially shared beam-forming network (BFN) is proposed. The configuration consists of four sequentially rotated two-arm Archimedean spiral antennas, backed by a finite ground plane and driven by a BFN. Every two diagonal antenna pairs are fed with differential phases to obtain similar co-polarized broadside transmitting (TX) and receiving (RX) beams. Each individual element has single feeding port and operates simultaneously as TX and RX over the same frequency. The proposed C-STAR approach utilizes antenna orientation, geometric symmetry, and partially shared BFN to overcome self-interference. In the absence of asymmetry and BFN imbalances, complete wideband self-interference cancellation is achieved without relying on frequency-, time-, space-, pattern-, antenna/port-, or polarization-multiplexing. The fabricated prototype has measured TX/RX isolation >38 dB, axial ratio <3.7 dB, and realized gain between 3 and 8.8 dBic over 1.25-2.5 GHz. The TX and RX radiation patterns are similar with envelope correlation coefficient >0.93.
关键词： transmit and receive (STAR),coupling,spiral,in-band full-duplex,Circular array,simultaneous self-interference cancellation,isolation
更新于2025-09-10 09:29:36
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Coherent full duplex radio over fiber system with multiple signal transmission
摘要： In this paper, a cost-effective and simple full duplex RoF (radio over fiber) system is developed from a simplex coherent RoF. At the transmitter, utilizing the magnitude and phase of the vector carrier, four different information are encoded simultaneously on the carrier light wave. Dividing the total carrier power into two branches, enable the transmitter to modulate two distinct information on each branch. The working of the system is described in two main sections namely uplink section and downlink section. In the first section, encoding of uplink transmitting information and decoding downlink information at the central office (CO) is described. In the second section, modulating downlink transmitting information and demodulating coherently the uplink receiving information at the base station (BS) are described. An algorithm based on fast Fourier transform is described for effectively canceling the phase noise (PN) at the BS. Considering the cost the source used to coherently detect the uplinked transmitted information, is again used as the carrier for downlink. Altogether, this system enables to transmit three different information on uplink and are faithfully received at the BS with an average of log(BER) value ?23 dB. And for downlink, one information is transmitted and is successfully received at the CO with log(BER) of ?9 dB. About 10 dB decrease in log(BER) values was found after the cancellation of PN.
关键词： full duplex,digital signal processing,coherent detection,phase noise
更新于2025-09-04 15:30:14
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Hybrid Beamforming Design for Full-Duplex Millimeter Wave Communication
摘要： Harnessing the abundant availability of spectral resources at millimeter wave (mmWave) frequencies is an attractive solution to meet the escalating data rate demands. Additionally, it has been shown that full-duplex (FD) communication has the potential of doubling the bandwidth efficiency. However, the presence of significant residual self-interference (SI), which is especially more pronounced at mmWave frequencies because of the non-linearities in the hardware components, erodes the full potential of FD in practice. Conventionally, the residual SI is canceled in the baseband using digital processing with the aid of a transmit precoder. In this work, we propose a hybrid beamforming design for FD mmWave communications, where the SI is canceled by the joint design of beamformer weights at the radio-frequency (RF) and the precoder as well as combiner in the baseband. Our proposed design preserves the dimensions of the transmit signal, while suppressing the SI. We demonstrate that our joint design is capable of reducing the SI by upto 30 dB, hence performing similarly to the interference-free FD system while being computationally efficient. Our simulation results show that the proposed design significantly outperforms eigen-beamforming.
关键词： Beamforming,Millimeter Wave,Hybrid Precoding,MIMO,Full-Duplex
更新于2025-09-04 15:30:14
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Precoding Design for Full-Duplex Transmission in Millimeter Wave Relay Backhaul
摘要： As the amount of user equipment and massive volumes of data continue to increase, high data rate requirements remain a major challenge, particularly in cellular networks. In networks composed of small cells, applying full-duplex (FD) millimeter wave (mmWave) wireless backhauls is a more effective and convenient approach than utilizing conventional optical fiber links. The mmWave communication technology is promising for future wireless communications due to its considerable available bandwidth, which is the basis of a high transmission rate. However, the short wavelength of mmWave leads to high propagation loss and shortens the transmission distance of the system. FD relaying can expand the coverage of the base station and achieve higher spectral efficiency than half-duplex (HD) transmission. However, the residual self-interference (SI) may degrade the performance of FD. The combination of mmWave and FD technologies compensates for the high path loss and realizes efficient transmission. In this paper, we consider an FD mmWave relay backhaul system and the SI of FD communication. We first propose an FD SI channel model in the mmWave band, which is composed of two parts: line-of-sight (LOS) SI and non-line-of-sight (NLOS) SI. According to the special mmWave MIMO structure limitation, two SI cancellation precoding algorithms are proposed to eliminate the SI in the system and achieve high spectral efficiency. The decoupled analog-digital algorithm eliminates the SI by utilizing the zero space of the channel, and the enhanced algorithm achieves higher performance. The spectral efficiency of the subconnected structure is analyzed. With appropriate performance loss, the simplified structure achieves significantly low configuration complexity.
关键词： precoding,Millimeter wave,Full-duplex,Relay,Self-interference
更新于2025-09-04 15:30:14