- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Channel modeling and analysis of OWC-massive MIMO systems
摘要： In this paper, we study the difference between the uplink and downlink channels of short-range slant free-space optical wireless between Ground - alpine base stations using massive MIMO linear arrays at both ends. The uplink and downlink atmospheric loss, scintillation, beam spreading and pointing error model of linear array slant range are constructed. The uplink and downlink atmospheric loss, spatial coherence length, receiver beamwidth, pointing error variance, relative mean square error (RMSE) and bit error rate (BER) are compared and analyzed under different distances of different wavelengths of light waves. After simulation analysis, it is concluded that the uplink and downlink atmospheric losses are the same, the uplink receiver beamwidth is larger than the downlink, and the downlink coherence length and the pointing error variance are larger than the uplink, and both monotonously change with the wavelength of the light wave and the propagation distance.
关键词： Optical wireless communication,MSE,Wavelength,Channel modeling,Massive MIMO
更新于2025-09-23 15:23:52
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[IEEE 2018 Ubiquitous Positioning, Indoor Navigation and Location-Based Services (UPINLBS) - Wuhan (2018.3.22-2018.3.23)] 2018 Ubiquitous Positioning, Indoor Navigation and Location-Based Services (UPINLBS) - Image Processing Based Indoor Localization System for Assisting Visually Impaired People
摘要： Indoor localization or indoor positioning system is a known as a process of detecting position of any object or people inside a building or room by different sensory data collected from different devices using different techniques such as radio waves, magnetic fields, acoustic signals or other procedures. However, lacking of a standard localization system is still a very big concern. Solution of this issue can be very beneficial for people in many cases but it can be especially very beneficial for the visually impaired people. In this paper, an image processing based indoor localization system has been developed using OpenCV and Python by following color detection technique to detect position of the user with maximum accuracy and then location of user is determined by analyzing that location matrix. Location accuracy depends on the size of the matrix and successful identification of target color. Firebase real time database was added to the system which made real time operations between server and the user end device easier. To justify the proposed model, successful experiments were conducted in indoor environments as well and correct result was achieved each time by detecting accurate locations. This will be very advantageous to observe the fully or partially sightless people and guide them towards their destination and also to inspect them for their security purpose.
关键词： Color Segmentation,Indoor localization,Image Processing,Indoor positioning system,Wireless communication,Connected object detection
更新于2025-09-23 15:23:52
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Error performance of optical wireless communication systems exercising BPSK subcarrier intensity modulation in non-Kolmogorov turbulent atmosphere
摘要： Subcarrier intensity modulation (SIM) scheme is preferred due to efficient bandwidth usage superiority over other modulation techniques such as on–off keying (OOK), pulse position modulation (PPM). In this paper, we investigate the bit error rate (BER) performance of optical wireless communication (OWC) system using binary phase shift keying (BPSK) SIM in non-Kolmogorov turbulent atmosphere. We pay attention to the weak turbulence conditions by using Rytov approximation and considering that the receiver is a PIN photodetector. Propagating beam type is Gaussian. It is seen that BER performance of the BPSK SIM OWC is significantly affected from non-Kolmogorov power law exponent, load resistor, responsivity of the PIN photodetector, bandwidth, beam source size, turbulence strength and noise factor.
关键词： Subcarrier intensity modulation,Optical wireless communication,Bit error rate,Atmospheric turbulence
更新于2025-09-23 15:23:52
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[IEEE 2018 International Conference on Electrical Engineering and Computer Science (ICECOS) - PANGKAL PINANG, Indonesia (2018.10.2-2018.10.4)] 2018 International Conference on Electrical Engineering and Computer Science (ICECOS) - Design and Implementation of Analog Transceiver Circuit for Patient Monitoring System based on OWC
摘要： In this paper, we present the design and implementation of analog front-end (AFE) module for patient monitoring system based on optical wireless communication (OWC). The communication link uses visible light as a downlink and IR as an uplink communication. The wireless patient monitoring system consists of two parts: host or coordinator and client or patient device. On the patient device part, we designed the PCB with a shield configuration so the AFE module can be connected directly to GPIO’s microcontroller unit (MCU) without any cable. Moreover, the AFE module is attempted to have a similar size with the MCU. Hence, the patient device has a small-size, minimum of wires, wearable, and low-complexity. The AFE receiver output is a digital waveform. Therefore, it is compatible with On-off Keying (OOK) modulation. The AFE module can be switched digitally up to 25 KHz of optical frequency for visible light downlink and 1500 Hz optical frequency for IR uplink. The optical link distance can reach up to 2 meters with 0o of reception angle.
关键词： Visible light communication,Wearable patient monitoring,IR communication,Optical Wireless Communication (OWC),Analog Front-End
更新于2025-09-23 15:22:29
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[IEEE 2018 International Conference on Intelligent and Innovative Computing Applications (ICONIC) - Mon Tresor, Plaine Magnien, Mauritius (2018.12.6-2018.12.7)] 2018 International Conference on Intelligent and Innovative Computing Applications (ICONIC) - Development of an IR-based Device for Wireless Communication in Community Health Centres
摘要： With the increase in implementation of advanced communication equipment, especially in the medical sector, finding solutions to anticipated problems has become paramount. Our envisaged problem is the uneasy procedure of taking patients’ variables frequently in community health centers, where there is usually minimal support staff. This paper indicates that human variables such as body temperature and movement at a special ward in a community health care center are transferable from one computer to another. However, our implementation integrated a temperature sensor (LM35), pyroelectric infrared, and infrared to a low-cost Arduino-generic Lilypad microcontroller (as the transmitter). The developed device was able to communicate with the receiver side (comprised of Arduino Mega, infrared receiver, and a computer). We were able to transfer data seamlessly from Mr. C. E. Ngene to a remote computer for analysis. This project will make up for the unavailability of expensive devices and low workforce in the rural community health centers. This designed device can help patients to be attended to quickly as the patients start to have issues.
关键词： sensors,infrared,health,remote monitoring,optical wireless communication
更新于2025-09-23 15:22:29
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Optical Wireless Communication Based Indoor Positioning Algorithms: Performance Optimisation and Mathematical Modelling
摘要： In this paper, the performance of the optimal beam radius indoor positioning (OBRIP) and two-receiver indoor positioning (TRIP) algorithms are analysed by varying system parameters in the presence of an indoor optical wireless channel modelled in line of sight configuration. From all the conducted simulations, the minimum average error value obtained for TRIP is 0.61 m against 0.81 m obtained for OBRIP for room dimensions of 10 m × 10 m × 3 m. In addition, for each simulated condition, TRIP, which uses two receivers, outperforms OBRIP and reduces position estimation error up to 30%. To get a better understanding of error in position estimation for different combinations of beam radius and separation between light emitting diodes, the 90th percentile error is determined using a cumulative distribution frequency (CDF) plot, which gives an error value of 0.94 m for TRIP as compared to 1.20 m obtained for OBRIP. Both algorithms also prove to be robust towards change in receiver tilting angle, thus providing flexibility in the selection of the parameters to adapt to any indoor environment. In addition, in this paper, a mathematical model based on the concept of raw moments is used to confirm the findings of the simulation results for the proposed algorithms. Using this mathematical model, closed-form expressions are derived for standard deviation of uniformly distributed points in an optical wireless communication based indoor positioning system with circular and rectangular beam shapes.
关键词： position estimation,channel modelling,raw moments,optical wireless communication,indoor positioning system,cumulative distribution frequency,standard deviation
更新于2025-09-23 15:22:29
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A D-band Multiplier-based OOK Transceiver with Supplementary Transistor Modeling in 65-nm Bulk CMOS Technology
摘要： A D-band on-off keying (OOK) transceiver chipset is fabricated in a 65-nm bulk CMOS technology as a low-cost and highly-integrative solution to short-distance wireless connectivity. Supplementary transistor modeling is performed for accurate circuit design at mm-wave frequencies. To overcome low transistor fmax and reduce DC power consumption, the transmitter employs a frequency-multiplier-based architecture with no power amplifier. The receiver adopts a non-coherent architecture consisting of a DC-coupled three-stage differential amplifier and an envelope detector. The OOK transmitter exhibits a measured output power of -9.8 dBm and on-off level difference of 13.2 dB at 134.1 GHz. The receiver shows a measured average responsivity of 4.1 kV/W and a noise equivalent power of 211.4 pW/Hz1/2 over all D-band frequencies. The DC power consumption of the transmitter and receiver are 76 mW and 32.5 mW, respectively. The transceiver is tested in both on-chip loopback and air-channel configurations, and demonstrates data transmission up to 10 Gbps and 2 Gbps at a distance of 0.03 m, respectively.
关键词： transceiver,transistor modeling,D-band,wireless communication,low-cost bulk CMOS,OOK
更新于2025-09-23 15:22:29
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[IEEE 2018 Wave Electronics and its Application in Information and Telecommunication Systems (WECONF) - Saint-Petersburg, Russia (2018.11.26-2018.11.30)] 2018 Wave Electronics and its Application in Information and Telecommunication Systems (WECONF) - On-Board Unlimited Aircraft Complex of Environmental Monitoring
摘要： the problems of the creation and use of autonomous UAVs for environmental monitoring of the earth and sea surfaces, as well as the state of ice fields are considered. Technical features of power supply, navigation system, wireless transmission channel and encryption of transmitted data are evaluated. A variant of the equipment of an autonomous complex for monitoring subsurface layers based on six-engine drone with the use of an ultra-wideband radar for implementing the functions of monitoring hazardous objects (forest fires, areas of man-made and natural emergencies), the detection of people and physical objects in the review of marine and coastal zones, as well as ice covers and subsurface layers.
关键词： UAV,autonomy,wireless communication,power supply,navigation
更新于2025-09-23 15:22:29
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[IEEE 2018 28th International Telecommunication Networks and Applications Conference (ITNAC) - Sydney, Australia (2018.11.21-2018.11.23)] 2018 28th International Telecommunication Networks and Applications Conference (ITNAC) - CamThings: IoT Camera with Energy-Efficient Communication by Edge Computing based on Deep Learning
摘要： In recent years, the demand for IoT cameras has increased due to the high demand for image data. However, the image sensor is unsuitable as an energy-constrained edge device for IoT due to its high-power consumption. Therefore, periodic on–off scheduling of IoT cameras is a promising approach since video recording using image sensors is energy-intensive. Due to the constrained computing performance of edge devices, IoT is still based on cloud computing with energy leaks by transmitting all the data of edge devices to cloud. In this paper, we proposed energy-efficient communication via edge computing based on deep learning, which reduces power consumption by transmitting only images of interest classified using edge computing. We also designed and implemented CamThings, which is an energy-efficient IoT camera with periodic on–off scheduling and the proposed energy-efficient communication. To analyze and evaluate the efficiency of the proposed communication scheme, we implemented a power consumption model for CamThings. In an environment with a low interest ratio, the proposed CamThings is superior to the baseline method with only periodic on–off scheduling in terms of power consumption and lifetime. When the scheduling period T is 5s and the interest ratio is 0.1, the proposed method consumed 41% less power than the baseline method. As a result, CamThings has a lifetime of more than one month.
关键词： Wireless Communication,Energy Efficiency,Edge Computing,IoT Camera,Deep Learning
更新于2025-09-23 15:22:29
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Hybrid DCO-OFDM, ACO-OFDM and PAM-DMT for Dimmable LiFi
摘要： This paper proposes a hybrid orthogonal frequency division multiplexing (OFDM) modulation termed as hybrid DC-biased asymmetrically-clipped pulse-amplitude-modulated OFDM (HDAP-OFDM) for providing power efficient communication and dimming control for light fidelity (LiFi) schemes. The proposed HDAP-OFDM is a combination of three OFDM formats: DC-biased optical OFDM (DCO-OFDM), asymmetrically clipped optical OFDM (ACO-OFDM) and pulse amplitude modulated discrete multitone (PAM-DMT). In HDAP-OFDM, the lower-index subcarriers carry DCO-OFDM, while the remaining higher subcarriers carry ACO-OFDM on the odd-index subcarriers and PAM-DMT on the even-index subcarriers. Mathematical analysis shows that the required DC bias for HDAP-OFDM is a function of the required dimming levels and the root mean square of the three of its components. Furthermore, an algorithm is presented to simulate the dimming control of HDAP-OFDM. Simulations results indicate that by adjusting the proportion of subcarriers for the three OFDM/DMT elements, HDAP-OFDM can have a wide dimming range, a low peak to average power ratio, and high power efficiency. Results also show that at a bit error rate of 10-3 and a dimming range of 3% to 97%, HDAP-OFDM exhibits 8 dB more optical and electrical power efficiency than existing asymmetrical hybrid optical OFDM.
关键词： HDAP-OFDM,optical wireless communication,DC bias,OFDM,dimming,LiFi
更新于2025-09-23 15:21:21