Daylight integrated indoor VLC architecture: An energy‐efficient solution

Modern railway services are required to deliver good quality services to the passenger throughout the whole journey. These include improved performances, safety, and reduce delays. There is also the requirement for in‐train customer experience such as infotainment and access to reliable communication systems. The railway industry has employed different types and generations of communication systems in recent times. Signaling systems were used at the early stage of the railway services. Today, communication systems such as the second‐generation communication system, also known as the global system for mobile communications (GSM), the Third‐generation (3G) and the Fourth‐generation (4G) are utilized in the railway industry. In this paper, we present a brief history of railway communication systems, their features and applications. In addition, we discuss the technical challenges and potential solutions of in‐train communication systems and how data can be distributed on‐board and between the train coaches using state of the art and hybrid communication technologies.

Section: Inside Train Communicationmentioning

confidence: 99%

Communication systems of high‐speed railway: A survey

Gheth

Rabie

Adebisi

et al. 2021

“…Even in high‐speed railway VLC can find its application 11 to facilitate the improved connectivity. As the lighting fixtures are everywhere and recently replaced by the white light‐emitting diode (WLED) 12,13 it can be used as a transmitter for simultaneous data transmission. This upheaval in the lighting paradigm creates an opportunity for VLC to be commercially viable in the coming years.…”

Section: Introductionmentioning

confidence: 99%

Signal to interference plus noise ratio improvement of a multi‐cell indoor visible light communication system through optimal parameter selection complying lighting constraints

Chatterjee

Sabui

Khan

et al. 2021

Self Cite

To achieve improved communication and illumination performances of a multi‐cell indoor visible light communication system, the selection of transmitter configuration and receiver's field of view (FoV) play a critical role. Based on multiple criteria decision modeling, a design‐centric methodology is proposed in this paper to determine the optimal transmitter configuration and receiver's FoV under lighting constraints. These optimal parameter selections are instrumental to obtain a highly uncorrelated channel, thus significantly mitigate both co‐channel interference from the neighboring transmitter and intersymbol interference due to multipath reflection. The implication for the optimum selection is explored using two communication false(Ptrue‾sig,Ptrue‾intffalse) and two lighting (Eavg, UO) performance indicating metrics. For a typical indoor scenario, three different transmitter arrangements with varying half‐power beam‐width are considered as alternatives. Furthermore, the signal to interference plus noise ratio (SINR) is tested over the communication floor (CF) by a simple receiver structure with a single photodiode. Incorporating the optimal transmitter configuration and receiver's FoV, 36.13 dB average SINR and 345 lx average horizontal illuminance is achieved. Analytically obtained SINR is also validated using a commercial ray tracing optical software for different positions over the CF. In comparison with the state of the art non‐optimal and sub‐optimal solutions, the proposed scheme, without real‐time computational complexity exhibits noteworthy improvement in SINR performance at expense of a trivial drop in overall uniformity of horizontal illuminance.

“…But the scheme requires more computing resources and overlooks the camera's capturing angles. Comparing with visible light channel communication schemes, [9][10][11] the invisible screen-camera short-range communication method is not required extra hardware while ensuring imperceptible for human eyes. There is an invisible screen-camera communication schemes called HA-QL in IEEE 802.15.7-2018 standards.…”

Section: Introductionmentioning

confidence: 99%

MobiScan: An enhanced invisible screen‐camera communication system for IoT applications

Xiao

Liu

et al. 2020

In recent years, dynamic and invisible screen‐camera short‐range communication for IoT devices have become a popular research field due to its superior user experience and no‐extra hardware required. However, most existing screen‐camera communication systems suffer from poor data security, high computational overhead, and limited capture angle, which make them infeasible in practice. In this work, we propose MobiScan, a dynamic and invisible screen‐to‐camera communication system that is able to ensure data security, real‐time communication, and flexible capture angle. MobiScan is composed of two parts: a novel fast frame correction scheme and a multilevel data pattern scheme to address the above problems. The fast frame correction scheme proposes a novel frame correct approach that utilizes the sensor data on the smartphone to correct the captured frame by reproducing the relationship between positions of the screen and the smartphone. Through this method, the scheme can save frame correction time without calculating frame content to identify the degree of deformation. The multilevel data pattern scheme protects the data privacy by sending the classified information to targeted users, which can reduce the time overhead and extend the application scenario by redesigning the data structure. The experimental results show that for flexible capture angle problem, the maximum capture angle is 180° in the rotate view and 60° in the side view, bottom view, and overlook view. For real‐time communication problem, the time overhead is reduced by 90% in the procedure of the frame correction. In the data decoding process, the time overhead is reduced by 10%. MobiScan enables a flexible capture angle on the PC platform for secure and real‐time communication.