Underground Channel Model for Visible Light Wireless Communication Based on Neural Networks

The OFDM technology is applied in the mobile communication system of underground coal mine, the wireless communication system channel of underground coal mine is researched. The underground channel model is established, and the simulation is taken for testing the performance of system. The simulation results show that the OFDM technology can be applied in the mobile communication system in underground coal mine, and the transmission rate of the system and the ability of anti-interference are improved.

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Automatic Detection of Arrhythmia Based on Multi-Resolution Representation of ECG Signal

Sensors ◽

10.3390/s20061579 ◽

2020 ◽

Vol 20 (6) ◽

pp. 1579

Author(s):

Dongqi Wang ◽

Qinghua Meng ◽

Dongming Chen ◽

Hupo Zhang ◽

Lisheng Xu

Keyword(s):

Neural Networks ◽

Deep Learning ◽

Deep Neural Networks ◽

Channel Model ◽

Expert Knowledge ◽

Automatic Detection ◽

Data Representation ◽

Learning Technology ◽

Arrhythmia Detection ◽

Automatic Feature Extraction

Automatic detection of arrhythmia is of great significance for early prevention and diagnosis of cardiovascular disease. Traditional feature engineering methods based on expert knowledge lack multidimensional and multi-view information abstraction and data representation ability, so the traditional research on pattern recognition of arrhythmia detection cannot achieve satisfactory results. Recently, with the increase of deep learning technology, automatic feature extraction of ECG data based on deep neural networks has been widely discussed. In order to utilize the complementary strength between different schemes, in this paper, we propose an arrhythmia detection method based on the multi-resolution representation (MRR) of ECG signals. This method utilizes four different up to date deep neural networks as four channel models for ECG vector representations learning. The deep learning based representations, together with hand-crafted features of ECG, forms the MRR, which is the input of the downstream classification strategy. The experimental results of big ECG dataset multi-label classification confirm that the F1 score of the proposed method is 0.9238, which is 1.31%, 0.62%, 1.18% and 0.6% higher than that of each channel model. From the perspective of architecture, this proposed method is highly scalable and can be employed as an example for arrhythmia recognition.

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Interference Mitigation for Visible Light Communications in Underground Mines Using Angle Diversity Receivers

Sensors ◽

10.3390/s20020367 ◽

2020 ◽

Vol 20 (2) ◽

pp. 367 ◽

Cited By ~ 6

Author(s):

Pablo Palacios Játiva ◽

Milton Román Cañizares ◽

Cesar A. Azurdia-Meza ◽

David Zabala-Blanco ◽

Ali Dehghan Firoozabadi ◽

...

Keyword(s):

Visible Light ◽

Mine Working ◽

Channel Model ◽

Underground Mining ◽

Cumulative Distribution ◽

Line Of Sight ◽

Delay Spread ◽

Noise Power ◽

Working Face ◽

Angle Diversity

This paper proposes two solutions based on angle diversity receivers (ADRs) to mitigate inter-cell interference (ICI) in underground mining visible light communication (VLC) systems, one of them is a novel approach. A realistic VLC system based on two underground mining scenarios, termed as mining roadway and mine working face, is developed and modeled. A channel model based on the direct component in line-of-sight (LoS) and reflections of non-line-of-sight (NLoS) links is considered, as well as thermal and shot noises. The design and mathematical models of a pyramid distribution and a new hemi-dodecahedral distribution are addressed in detail. The performances of these approaches, accompanied by signal combining schemes, are evaluated with the baseline of a single photo-diode in reception. Results show that the minimum lighting standards established in both scenarios are met. As expected, the root-mean-square delay spread decreases as the distance between the transmitters and receivers increases. Furthermore, the hemi-dodecahedron ADR in conjunction with the maximum ratio combining (MRC) scheme, presents the best performance in the evaluated VLC system, with a maximum user data rate of 250 Mbps in mining roadway and 120 Mbps in mine working face, received energy per bit/noise power of 32 dB and 23 dB, respectively, when the bit error rate corresponds to 10 − 4 , and finally, values of 120 dB in mining roadway and 118 dB in mine working face for signal-to-interference-plus-noise ratio are observed in a cumulative distribution function.

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A Study of Shadowing on Indoor Visible-Light Wireless Communication Utilizing Plural White LED Lightings

Wireless Personal Communications ◽

10.1007/s11277-005-8734-x ◽

2005 ◽

Vol 34 (1-2) ◽

pp. 211-225 ◽

Cited By ~ 30

Author(s):

Toshihiko Komine ◽

Shinichiro Haruyama ◽

Masao Nakagawa

Keyword(s):

Wireless Communication ◽

Visible Light ◽

White Led

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The Research on the Police Adaptive Wireless Communications

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.850-851.549 ◽

2013 ◽

Vol 850-851 ◽

pp. 549-552

Author(s):

Chuan Sheng Zhao

Keyword(s):

Wireless Communications ◽

Wireless Communication ◽

Channel Model ◽

Model Simulation ◽

Excellent Performance ◽

Adaptive Equalizers ◽

Time Invariant

Most Current researches about the police adaptive wireless communication are concentrated on the area of the time-invariant channel model, which is not fit to the requirement of police application. This paper designed an time-variant ISI channel model, according to the characteristics of police wireless communication. And analyzed the performance of the LMS and the RLS algorithms in DFE structure adaptive equalizers, under the time-variant ISI channel model. Simulation shows that the designed adaptive equalizers obtained excellent performance.

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A channel model for indoor visible light communication system with specular reflection

2017 16th International Conference on Optical Communications and Networks (ICOCN) ◽

10.1109/icocn.2017.8121510 ◽

2017 ◽

Cited By ~ 3

Author(s):

Jian Chen ◽

Chenchen Yan

Keyword(s):

Visible Light ◽

Communication System ◽

Channel Model ◽

Specular Reflection ◽

Visible Light Communication

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Dual-Branch Pre-Distorted Enhanced ADO-OFDM for Full-Duplex Underwater Optical Wireless Communication System

Photonics ◽

10.3390/photonics8090368 ◽

2021 ◽

Vol 8 (9) ◽

pp. 368

Author(s):

Zixian Wei ◽

Yibin Li ◽

Zhaoming Wang ◽

Junbin Fang ◽

Hongyan Fu

Keyword(s):

Wireless Communication ◽

Spectral Efficiency ◽

Orthogonal Frequency Division Multiplexing ◽

Channel Model ◽

Full Duplex ◽

Optical Channel ◽

Optical Wireless Communication ◽

Optical Wireless ◽

Hardware Complexity ◽

Double Gamma Function

In this paper, dual-branch pre-distorted enhanced asymmetrically clipped direct current (DC) biased optical orthogonal frequency division multiplexing (PEADO-OFDM) for underwater optical wireless communication (UOWC) is firstly proposed and simulated. The performances of PEADO-OFDM on the underwater optical channel model (UOCM) are analyzed and further compared with the typical ADO-OFDM. Using the Monte Carlo method for the modeling of UOCM, we adopt a double-gamma function to represent three different water qualities including clear, coastal and harbor waters. The full-duplex architecture enables the removal of Hermitian symmetry (HS) from conventional optical OFDM and can increase the spectral efficiency at the cost of hardware complexity. A new PEADO-OFDM transmitter is also proposed to reduce the complexity of the transmitter. The simulation results exhibit that our proposed dual-branch PEADO-OFDM scheme outperforms the typical ADO-OFDM scheme in spectral efficiency, bit error rate (BER) and stability over the underwater channels of three different water qualities.

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Three-Dimensional MIMO Channel Model with High-Mobility Wireless Communication Systems Using Leaky Coaxial Cable in Rectangular Tunnel

International Journal of Antennas and Propagation ◽

10.1155/2021/6622135 ◽

2021 ◽

Vol 2021 ◽

pp. 1-11

Author(s):

Kai Zhang ◽

Fangqi Zhang ◽

Guoxin Zheng ◽

Lei Cang

Keyword(s):

Wireless Communication ◽

Communication Systems ◽

Channel Model ◽

Mimo System ◽

Three Dimensional ◽

High Mobility ◽

Coaxial Cable ◽

Mimo Channel ◽

Wireless Communication Systems ◽

Rectangular Tunnel

With the rapid development of high-mobility wireless communication systems, e.g., high-speed train (HST) and metro wireless communication systems, more and more attention has been paid to the wireless communication technology in tunnel-like scenarios. In this paper, we propose a three-dimensional (3D) nonstationary multiple-input multiple-output (MIMO) channel model with high-mobility wireless communication systems using leaky coaxial cable (LCX) inside a rectangular tunnel over the 1.8 GHz band. Taking into account single-bounce scattering under line-of-sight (LoS) and non-line-of-sight (NLoS) propagations condition, the analytical expressions of the channel impulse response (CIR) and temporal correlation function (T-CF) are derived. In the proposed channel model, it is assumed that a large number of scatterers are randomly distributed on the sidewall of the tunnel and the roof of the tunnel. We analyze the impact of various model parameters, including LCX spacing, time separation, movement velocity of Rx, and K-factor, on the T-CF of the MIMO channel model. For HST, the results of some further studies on the maximum speed of 360 km/h are given. By comparing the T-CF between the dipole MIMO system and the LCX-MIMO system, we can see that the performance of the LCX-MIMO system is better than that of the dipole MIMO system.

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