- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Underwater optical wireless sensor networks using resource allocation
摘要： Optical wireless communications is an energy efficient and cost-effective solution for high speed and high secure wireless connections. In this paper, we propose an underwater optical wireless sensor network using multiple input multiple output technique and power allocation algorithm for supporting multiple users with the impacts of underwater channel uncertainty interferences. In proposed power allocation algorithm, all the LED nodes in are coordinated and controlled by a central controller; each LED node supports all the users within its field of view. To separate users, optical code division multiple access is used; cyclic optical orthogonal code working as CDMA code is employed. At the receiver, a minimal mean squared error (MMSE) filter is uniquely designed for each user. The MMSE filters and the assigned power can be jointly optimized to improve the overall throughput and signal to noise ratio. Since the system performance may be impacted by the underwater channel uncertainty, the proposed power allocation can use the predicted channel uncertainty variance to reduce the interference of the channel uncertainty and improve the signal to noise ratio. Compared to the equal power allocation algorithm, the proposed algorithm can support longer transmission distance, higher bit rate and lower bit error rate.
关键词： Multiple access interference,Underwater communications,Wireless sensor networks,Channel uncertainty,MIMO system,CDMA,Optical wireless communications,Resource allocation
更新于2025-09-23 15:23:52
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[IEEE 2018 25th International Conference "Mixed Design of Integrated Circuits and System" (MIXDES) - Gdynia, Poland (2018.6.21-2018.6.23)] 2018 25th International Conference "Mixed Design of Integrated Circuits and System" (MIXDES) - Study of Wireless Communications Link at Subterahertz Frequencies Using FET-based Detectors
摘要： This paper focuses on the wireless link development deploying (sub)THz waves. The article describes authors’ initial approach to the research and experiments dealing with THz communications. Presented work summarises the theory and achieved results in a ?led of FET-based THz detectors and readout circuits aimed at wireless THz data transmission. Our main goal was to provide proper data transmission utilising (sub)THz carrier wave — this has been experimentally achieved at 170 GHz and 289 GHz.
关键词： THz,data transmission,FET-based detectors,wireless communications
更新于2025-09-23 15:23:52
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An optical wireless communication system deploying active high-pass pre-emphasis circuit for high speed application
摘要： This article presents a high-speed optical wireless communication link with a newly proposed pre-emphasis circuit to increase transmission performance at higher data rates. The effectiveness of the pre-emphasis circuit has been verified through testing on an optical wireless link implemented with existing laser communications components in our laboratory operating at 1550 nm. When the proposed pre-emphasis circuit is included in the optical wireless link, we achieved bit-error-rate (BER) power penalty improvements of 1.6, 2.2, and 1.0 dB at 155 Mbps, 622 Mbps, and 1.244 Gbps, respectively at the BER of 2 × 10?3 compared with the optical wireless communication links without pre-emphasis circuit. For the lower BER of 10?9, BER power penalty improvements of 2.2, 3.7, 0.7 dB at 155 Mbps, 622 Mbps, and 1.244 Gbps are observed, which show the effectiveness of our proposed pre-emphasis circuit in optical wireless communications link.
关键词： pre-emphasis,optical communications,optical wireless communications,free space optical communications,optical wireless link
更新于2025-09-23 15:22:29
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[IEEE 2018 IEEE International Conference on Internet of Things and Intelligence System (IOTAIS) - BALI, Indonesia (2018.11.1-2018.11.3)] 2018 IEEE International Conference on Internet of Things and Intelligence System (IOTAIS) - Optical Internet of Things within 5G: Applications and Challenges
摘要： The fifth generation (5G) telecommunications standards are being developed to meet the growing demands for high-speed wireless networks (i.e., few tens of Gigabits per second). The 5G standard stems largely from an increasing number of users and plethora of different devices, collectively referred to as smart devices, connecting to a network as part of Internet-of-Things (IoT). A few potential technologies have emerged for 5G such as millimeter waves, massive multiple-input multiple-output, and small cell communications. Although these technologies would satisfy the requirements of 5G, there is a complementary alternative wireless technology of optical wireless communications (OWC), which is being considered. As part of OWC, visible light communications (VLC) and optical camera communications (OCC) are the most attractive options for 5G networks and beyond. VLC with huge frequency spectrum integrated with IoT can open up a wide range of indoor and outdoor applications as part of future smart environments. This paper provides an overview of the all-optical IoT (OIoT) focusing on VLC and OCC based potential applications and challenges as part of 5G standards.
关键词： light emitting diodes (LEDs),visible light communications (VLC),Internet of things (IoT),Optical wireless communications (OWC),optical camera communications (OCC)
更新于2025-09-23 15:22:29
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[IEEE 2018 New Trends in Signal Processing (NTSP) - Liptovsky Mikulá?, Slovakia (2018.10.10-2018.10.12)] 2018 New Trends in Signal Processing (NTSP) - Possibilities of Using FSO/RF Technology in Military Communication Systems
摘要： The article presents an overview of selected aspects of wireless communications considering military applications. The main attention is paid to performance analysis of radio and free space optics technologies. There are also presented some activities to get new capabilities of wireless communications using procedure of dynamic spectrum access, wideband and narrowband radio system, and free space optical system operated in infrared spectrum. In the summary, possibilities of radio-optical hybrid communication systems and their application in military areas have been defined.
关键词： hybrid wireless communications,frequency management,software-defined radio,frequency broker,cognitive radio
更新于2025-09-23 15:22:29
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[IEEE 2018 26th International Conference on Software, Telecommunications and Computer Networks (SoftCOM) - Split (2018.9.13-2018.9.15)] 2018 26th International Conference on Software, Telecommunications and Computer Networks (SoftCOM) - Car to X Communication with Optical Wireless as Support and Alternative to RF-Technologies for Roads and Future Transportation
摘要： Among the different types of lasers and light sources for Communications, new components are becoming more and more important also for Optical Wireless and Optical Sensing applications. In this contribution, combinations of Optical- and RF-Wave Propagation are illustrated, considering also new technologies of lasers and fibre lasers. The presentation includes Optical Wireless Communication (OWC, well known as Free Space Optics (FSO)) as hybrid transmission methods with telecommunication technologies (like WIFI, RF- and Satellite Communications) and also Sensing Technologies (like LiDAR and radar combinations). Important characteristics of physical layer including useful Modulations, Forward Error Correction Coding for single light source are considered. Furthermore, different cases for enhancing the SNR in daytime condition are discussed. The contribution deals with possible fields of application for optical wireless in conjunction with automated driving.
关键词： Car to X Communication,Optical Wireless Communications,light sources,hybrid networks
更新于2025-09-23 15:22:29
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Energy Harvesting Wireless Communications || Power Allocation for Point-to-Point Energy Harvesting Channels
摘要： This chapter considers a point-to-point EH wireless channel when the transmitter and the receiver are powered by EH. Under this setup, we first maximize various system utilities (such as the end-to-end throughput and the non-outage probability) via adaptive power allocation over time subject to the EH constraints at the transmitter, where the accumulatively consumed energy should not exceed that accumulatively harvested at any time. Under various CSIT and ESIT assumptions, we discuss the respective optimal designs. For example, in the noncausal CSIT and ESIT case, the optimal offline power allocation is shown to follow a non-decreasing and piecewise-constant (or staircase-like) pattern for the Gaussian channel case, and the optimal transmit power corresponds to a staircase water-filling power allocation for the fading channel case. In the causal ESIT and CSIT case, applicable online optimization strategies include dynamic programming-based and heuristically designed power allocation strategies. We also point out several open problems under different ESIT and CSIT considerations. For example, the throughput maximization problems under the case with causal CSIT and noncausal ESIT and the case with no CSIT and noncausal/causal ESIT remain unsolved in general, while the outage probability minimization problems under causal CSIT and noncausal/causal ESIT are also open problems at large. Furthermore, we extend the power allocation policies to other scenarios by considering other practical constraints such as limited battery capacity and imperfect circuits. We show that in the noncausal CSIT and ESIT case, the staircase power allocation with Gaussian channel and the staircase water-filling power allocation with fading channels can be modified to take these new practical constraints into account. With imperfect circuits, the EH transmitter should employ an on-off power allocation, which turns the transmitter into a sleep mode to save power in order to transmit more energy efficiently in the wake-up mode to tradeoff between the transmit energy consumption versus the circuit energy consumption. These new offline power allocation strategies motivate new online power allocation approaches with only causal CSIT and ESIT. Finally, we provide discussions on the transmit and receive power allocations in the case with EH transmitter and EH receiver, where in addition to the transmitter, the receiver's power consumption is also subject to an EH constraint. Under such a scenario, it is essential for the transmitter and the receiver to jointly optimize the transmit power and the code rate (hence, control the receive power consumption) to improve the end-to-end utility. Note that the case of EH receiver has not been widely investigated in the literature and there are rich open problems (e.g. under causal CSIT and ESIT) worth being pursued in future work.
关键词： power allocation,outage probability minimization,battery capacity,EH receiver,imperfect circuits,ESIT,wireless communications,throughput maximization,CSIT,Energy harvesting
更新于2025-09-23 15:22:29
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IEEE Access Special Section Editorial: Optical Wireless Technologies for 5G Communications and Beyond
摘要： Wide bandwidth and dense spatial reuse are of extreme importance for future wireless communication networks, including 5G and beyond. In particular, these properties are important to enable future wireless networks to cope with the explosive increase in the demand for high data-rate communications. Optical wireless communications (OWC) is a promising technology for achieving this goal due to the abundant reusable license-free optical spectrum. This potential of OWC attracted significant global attention both from communications and optoelectronics viewpoints, and continues to do so.
关键词： 5G,beam-steering,mixed FSO/fiber backhauling,OFDM,MIMO,Optical wireless communications,vehicle-to-vehicle communications,free-space optics,vehicle-to-infrastructure communications,network-layer aspects,visible-light communications
更新于2025-09-23 15:21:21
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[IEEE 2018 IEEE 5G World Forum (5GWF) - Silicon Valley, CA, USA (2018.7.9-2018.7.11)] 2018 IEEE 5G World Forum (5GWF) - Linear GFDM: A Low Out-of-band Emission Configuration for 5G Air Interface
摘要： This paper explores the ?exibility of generalized frequency division multiplexing (GFDM) for achieving the same performance as ?lter bank multicarrier (FBMC). We present a GFDM con?guration where the good spectral containment of FBMC is also achieved through a modi?cation in the GFDM transmission scheme. For evaluating the scheme’s performance, we estimate the bit error ratio (BER) under three channel models: i) pure additive Gaussian AWGN; ii) time-invariant frequency-selective; iii) time-variant frequency-selective (doubly dispersive). The spectral containment is measured through the power spectral density. Furthermore, the complementary cumulative distribution function (CCDF) of the peak-to-average power ratio (PAPR) is also estimated. The Linear GFDM waveform shows identical performance when compared to FBMC in the above test scenarios.
关键词： GFDM,wireless communications,FBMC,non-orthogonal waveforms,enhanced mobile broadband,5G
更新于2025-09-23 15:21:21
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[IEEE 2018 9th International Conference on Ultrawideband and Ultrashort Impulse Signals (UWBUSIS) - Odessa, Ukraine (2018.9.4-2018.9.7)] 2018 9th International Conference on Ultrawideband and Ultrashort Impulse Signals (UWBUSIS) - Features of Millimeter-Wave Ultra-Wideband Signals Application in Telecommunications
摘要： In the paper, the features of millimeter-wave ultra-wideband signals application, related to photon methods of generation and transmission of millimeter-wave signals, as well as the quasi-optical approach for modeling signal loss (amplification) are considered. It is proposed to use more accurate models of millimeter-wave ultra-wideband radio systems, which should correspond to the fundamental physical features of the propagation of millimeter waves, especially in urban conditions. It is shown that when calculating such systems it is necessary to take into account the noise associated with the method of generating millimeter waves.
关键词： energy budget,wireless communications,noise regime,ultra-wideband signal,millimeter-wave,radio-over-fiber
更新于2025-09-23 15:21:21