Nam-Tuan Le

• PhD
• Researcher at Advanced Remanufacturing and Technology Centre

Optical wireless communication is a promising emerging technology that addresses the limitations of radio-frequency-based wireless technologies. This study presents a new hybrid modulation method for optical camera communication (OCC), which integrates two waveforms transmitted from a single transmitter light-emitting diode (LED) and receives data...

Optical wireless communication is a promising emerging technology that addresses the limitations of radio-frequency-based wireless technologies. This study presents a novel hybrid modulation for optical camera communication (OCC); it integrates two waveforms transmitted from a single transmitter light-emitting diode (LED) and received by two rollin...

In this letter, a hybrid-encoding scheme is developed for an integrated optical camera communication (OCC)/light-fidelity (LiFi) system. A single multilevel light-emitting diode (LED) is used for transmitting both OCC and LiFi data. Two data streams are transmitted, where each stream is intended for LiFi and OCC. The first stream is transmitted at...

In order to develop wireless sensor networks, which are defined by the IEEE 802.15.4 specification, researchers are considering low-power wide-area networks (LPWAN) due to their advantages of being long range, low power, low cost, and highly mobile. The issue of mobility is covered in the IEEE 802.15.4g standard for supporting a smart utility netwo...

In order to develop wireless sensor networks, which are defined by the IEEE 802.15.4 specification, researchers are considering low-power wide-area networks (LPWAN) due to their advantages of being long range, low power, low cost, and highly mobile. The issue of mobility is covered in the IEEE 802.15.4g standard for supporting a smart utility netwo...

Localization has become an important aspect in a wide range of mobile services with the integration of the Internet of things and service on demand. Numerous mechanisms have been proposed for localization, most of which are based on the estimation of distances. Depending on the channel modeling, each mechanism has its advantages and limitations on...

Seamless connectivity is one of the key issues to consider when integrating two or more different wireless technologies. The exponential growth of wireless connectivity necessitates the convergence of ultra-dense heterogeneous networks. This is due to the fact that a single network may not be able to provide the high quality of service (QoS) requir...

The low power wide area has a lot of attraction to research from many researchers in the world due to their ability to offer connectivity to low-power devices over a large area. With the Internet of Things (IoT) systems, the low-power wide area technologies contributed a critical position. It can be complemented and replaced the conventional wirele...

Optical camera communication (OCC) exhibits considerable importance nowadays in various indoor camera based services such as smart home and robot-based automation. An android smart phone camera that is mounted on a mobile robot (MR) offers a uniform communication distance when the camera remains at the same level that can reduce the communication e...

Optical camera communication (OCC) exhibits considerable importance nowadays in various indoor camera based services such as smart home and robot-based automation. An android smart phone camera that is mounted on a mobile robot (MR) offers a uniform communication distance when the camera remains at the same level that can reduce the communication e...

The demand for autonomous vehicles is increasing gradually owing to their enormous potential benefits. However, several challenges, such as vehicle localization, are involved in the development of autonomous vehicles. A simple and secure algorithm for vehicle positioning is proposed herein without massively modifying the existing transportation inf...

The demand for autonomous vehicles is increasing gradually owing to their enormous potential benefits. However, several challenges, such as vehicle localization, are involved in the development of autonomous vehicles. A simple and secure algorithm for vehicle positioning is proposed herein without massively modifying the existing transportation inf...

Reports on the standards activities of the IEEE Communications Society(ComSoc) The standards development activities are conducted in partnership with the IEEE-Standard Association (SA) Standards Board (SASB), with appropriate, as needed liaison with other standards bodies. The ComSoc Standards Development Board or, in IEEE-SA’s nomenclature, COM/SD...

Copyright protection and information security are two most considered issues of digital data following the development of internet and computer network. As an important solution for protection, watermarking technology has become one of the challenged roles in industry and academic research. The watermarking technology can be classified by two categ...

As an extension of visible light communications (VLC), optical camera communications (OCC) are poised to play an important role in the success of VLC technology. Comparing with VLC systems based on photodiodes, OCC systems have a number of advantages in terms of hardware, communications channels, and business trends. However, these systems also hav...

In this paper, we propose an indoor image sensor communication (ISC) system comprising an attentive indoor environment in which rolling-shutter cameras (including smart phone cameras) are used to receive data from light sources. The challenges of intended system mainly come from the receiver side, including its rolling shutter mechanism, its low an...

Visible Light Communication (VLC) has emerged as a promising technology for wireless communication owing to advantages such as bandwidth, license, coexistence and security. Additionally, it was officially standardized by IEEE 802.15.7 in 2011. However, it faces certain challenges that can be considered as grounds to develop a revised version. Optic...

Compare with other communication system based RF technology, Optical Camera Communication (OCC) has limitation on data rate due to the low frame rate of camera. The limitation on data rate can be solved with multiple-input and multiple-output (MIMO) technology; and it is the final target of all researches on OCC. The MIMO topology can be implemente...

As an enhancement of cellular networks, the future-generation 5G network can be considered an ultra-high-speed technology. The proposed 5G network might include all types of advanced dominant technologies to provide remarkable services. Consequently, new architectures and service management schemes for different applications of the emerging technol...

Everything in the world is being connected, and things are becoming interactive. The future of the interactive world depends on the future Internet of Things (IoT). Software-defined networking (SDN) technology, a new paradigm in the networking area, can be useful in creating an IoT because it can handle interactivity by controlling physical devices...

This paper introduces a novel modulation scheme for vehicular communication in taking advantage of existing LED lights available on a car. Our proposed 2-Phase Shift Keying (2-PSK) is a spatial modulation approach in which a pair of LED light sources in a car (either rear LEDs or front LEDs) is used as a transmitter. A typical camera (i.e. low fram...

Everything in the world is being connected, and things are becoming interactive. The future of the interactive world depends on the future Internet of Things (IoT). Software-defined networking (SDN) technology, a new paradigm in the networking area, can be useful in creating an IoT because it can handle interactivity by controlling physical devices...

In recent decades, the main data traffic of mobile communication is based on the RF technology. Even though the efficiency from optimization for utilization or reuse is applied, there is a limitation of increased traffic demand of RF communication. Visible light communication (VLC) is a new technology that can cooperate with RF to address this limi...

Data failure in wireless communications considerably affects the reconstruction quality of transmitted data. Traditionally, fascinating trials have been conducted to overcome the data failure intensifying reliable reconstruction of a media. But, none of these efforts neither effective, computationally inexpensive nor simply configurable to reduce t...

In the contemporary world, the breakthrough of the ultra-modern technologies has been blessed with the camera. This device has become omnipresent either integrated on with other devices such as smartphones, notebooks, laptops, handheld devices and so on. In addition, digital signage, display and monitors have also become very widespread around us e...

Indoor positioning techniques has become a key research issue for future smart services because of the high market value in providing location-based services via smartphones and ondemand services. In image sensor communications (ISC) case, one of the main advantages of the indoor navigation system is that the LED itself can transmit its location in...

Localization is one of the key issues of demandable applications, especially smart services. Beside the traditional GPS based localization technique, the localization issue by visible light communications is promising market because of possibility of combining visible light communications with positioning technique for a high accurate, especially i...

As an enhancement of cellular networks, the future-generation 5G network can be considered an ultra-high-speed technology. The proposed 5G network might include all types of advanced dominant technologies to provide remarkable services. Consequently, new architectures and service management schemes for different applications of the emerging technol...

Visible light communication (VLC), which offers the possibility of using light sources for both illumination and data communications simultaneously, will be a promising incorporation technique with lighting applications. However, it still remains some challenges especially coverage because of field-of-view limitation. In this paper, we focus on thi...

Optical Camera Communication (OCC) is considered as an extension of IEEE 802.15.7 specification by same communication channel. Different with another technique, Optical Camera Communication used image sensor for receiver, so the characteristic of image sensor will effect on the operation and performance. In this paper we analyze and discuss the per...

With the development of semiconductors and the resulting effect on manufacturing costs, wireless interface platforms have become increasingly powerful and popular. This has resulted in widespread applications ranging from daily life activities to military services. In large-scale applications of wireless sensor networks such as military surveillanc...

With a view to laying foundation for Optical Wireless Communication (OWC) technology the IEEE 802.15 TG7r1 has started its journey since 2011 with prior nomenclature as " IEEE 802.15.7 ". This paper familiarizes the IEEE 802.15.7r1 (revision 1) OWC Task Group (TG) and provides a brief information about the standardization of OWC technology. The gra...

This paper introduces the asynchronous Optical Camera Communication (asynchronous OCC) using LED and rolling shutter camera as a pair of wireless communication. Aiming to enhance the capacity of unidirectional wireless link, the response of camera is measured, and then the operating frequency range, system architecture, decoding procedure and algor...

Digital signage (DS) has become a phraseology for recent technology, is gaining massive acceptance to the technology-dependent world. Though the development of DS includes the essence of advertisement purposes, the fusion strategy makes it promising for communication technology. This paper demonstrates a Symbiotic Digital Signage (SDS) system in wh...

This paper introduces infrastructure-to-vehicle (I2V) communication based on asynchronous optical camera communication (OCC), the transmitter of which can be an LED traffic light or electronic display, with the receiver being the existing front vehicle camera. In asynchronous OCC-based I2V communication, the key technique is an asynchronous scheme....

Wireless technologies based on radio frequencies (RFs) have always dominated other types of wireless technologies up until now. However, the recent proliferation of media-rich smart devices has pushed the RF spectrum usage to its limit. Therefore RF band expansion towards the optical spectrum is imminent in commercial scale. Indeed, the research on...

Beacons has turned into a key issue in Wireless Sensors Networks as furthermost of the localization methods use it as references to sense the location of the objects. Subsequently, outlier detection has become one of the crucial concern in wireless sensor networks (WSN) as the data reliability is greatly hampered by the interference and environment...

Visible light communication (VLC) which offers the possibility of using light sources for simultaneous illumination and data communications will be a promising incorporation technique with lighting application. In this paper, we will suggest one resource allocation for VLC broadcasting system which based on broadcasting visible light communication...

This paper introduces the Optical Camera Communication (OCC) based on Computer Vision. The practical issues of implementation of the asynchronous communication based Screen-to-Camera are performed. The asynchronous scheme proposed by our previous work is modified to be simple, suitable and reliable in order to apply in case of heterogeneous frame r...

As an extension of Visible Light Communication, Optical Camera Communications (OCC) will be a promising service for smart devices. Especially in line of sight marketing service and indoor localization application, by using camera which exists in smart devices, small amount of data (url link) can be broadcasted or find direction from the illuminatio...

A joint scheduling and optimal resource allocation scheme for wireless personal area network using visible light is proposed. In current IEEE 802.15.7 standard, multiple channel scheduling in medium access control (MAC) layer and variable data rate opportunity in physical layer (PHY) are performed separately. Therefore, the resources are not utiliz...

Indoor localization technique is one of the key research issues due to highly demandable market value to provide Location Based Services (LBS) using smart phone. In optical camera communication (OCC) case one of the main advantages in indoor navigation system is LED itself can transmit location information along with unique feature of a camera to d...

In wireless communication network, multi-channel communication technology is promising solution for throughput performance enhancement and collision avoidance. Similarly with visible light communication, multi-channel approach will be shown more advances due to the limitation of color channel and co-channel interference at photo detector. In this r...

The prevalence of build-in cameras smart phone and LED displays creates a novel opportunity to build camera-based optical wireless communication systems. However, for a practical real-time communication system, there are many consideration issues especially the synchronization of the shutter timing release with the lighting source. In this paper we...

This paper proposes software-based scheme for unidirectional communications of OCC system. Proposed scheme based on over-sampling technique will solve fully effects of exposure to the unidirectional OCC system where there is no synchronization. These schemes do not consider mitigating flicker, and then they are suitable for both global shutter and...

Wireless platforms are becoming less expensive and more powerful, enabling the promise of widespread use, everything from health monitoring to military sensing. In large scale applications like military surveillance, sensing coverage is essential for target detection and optimization of power consumption is important for lifetime extension of the n...

Visual multiplexing MIMO techniques will send independent streams of bits using the multiple elements of the light transmitter array and recording over a group of camera pixels can further enhance the data rates. The proposed system is a combination of the reliance on computer vision algorithms for tracking and OOK cell frame modulation. LED array...

Every shared wireless communication channel needs a medium-access control (MAC) protocol by which nodes contend for the channel and eventually transmit without collisions. Over the past several decades, many MAC protocols have been designed and several are in operation in wireless networks today. The MAC layer emulates a full-duplex logical communi...

Automatic Repeat reQuest (ARQ) is widely used in wireless systems to guarantee the reliable delivery of data packets. However with the current state of Visible Light Communication, especial intensity modulation and frequency handover, the traditional ARQ shows some limitation about collision probability and new link connection. This article we prop...

LED-ID (Light Emitting Diode-Identification) network is envisioned to be the next generation indoor wireless communication medium by which simultaneously high speed data transmission, identification, and illumination are possible. In spite of being extremely promising, it suffers from much impairment. Signals having different propagation paths can...

Inter-cell interference is the critical issue not only in cellular systems but also in visible light communication (VLC) systems. In this paper, an inter-cell interference mitigation using soft frequency reuse (SFR) for VLC is presented. Our proposed scheme aims to decrease inter-cell interference and get higher signal-to interference-and-noise rat...

Visible light communication (VLC) enables high speed wireless communication along with fulfilling the illumination requirement in the indoor environment. In this paper, we investigate the performance of a VLC system under multiple reflection condition. We minimize the effect of intersymbol interference (ISI) by using orthogonal frequency division m...

LED-ID (Light Emitting Diode - Identification) is one of the key technologies for identification, data transmission, and illumination simultaneously. This is the new paradigm in the identification technology environment. There are many issues are still now challenging to achieve high performance in LED-ID system. Collision issue is one of them. Act...

In Visible Light Communication (VLC) system, with the limitation of transmission range and Field Of View (FOV), LOS (Line of Sight) link between two transceivers should be guaranteed due to the straightness of the visible-light signal. Especially for indoor applications, link recovery is an advantage method to remain the link connection because of...

Priority MAC is an important issue in every communication system when we consider differentiated service applications. In this paper, we propose a mechanism to support priority MAC based on multi-parameters for IEEE 802.15.7 visible light communication (VLC). By using three parameters such as number of backoff times (NB), backoff exponent (BE) and...

Cognitive Radio technique exploits underutilized licensed spectrums to improve its bandwidth availability. Using CR technology, node is able to adapt its transmission and reception radio parameters including channel frequency dynamically according to local spectrum availability. In visible light communication, due to the limitation and heterogeneou...

An anti-collision protocol which tries to minimize the collision probability and identification time is the most important factor in all identification technologies. This paper focuses on methods to improve the efficiency of tag's process in identification systems. Our scheme, Binary Slotted Query Tree (BSQT) algorithm, is a memoryless protocol tha...

In wireless communication, cooperative communication can be voted as a best promising technique to enhance system reliability and performances. In Visible Light Communication (VLC) system, with the limitation of transmission range and Field Of View (FOV), cooperative communication shows more advantages in reliability and coverage. This article prop...

In this paper, we propose a mechanism to support priority MAC based on multi-parameter for IEEE 802.15.7 visible light communication (VLC). By using three parameters such as number of backoff times (NB), backoff exponent (BE) and contention window (CW), we provide priority for multilevel differentiated service. We consider beacon-enabled visible li...

IEEE 802.15.4 (low-rate Wireless Personal Area Networks-WPANs) [I) and IEEE 802.15.7 (Visible Light WPANs) [2) are one of the typical of WPANs which can support QoS through guaranteed time slots (GTS) mechanism to allocated a specific duration within a superframe structure for a TDM transmission. The low bandwidth utilization problem may occur in G...

Wireless sensor networks (WSNs) have attracted much attention in recent years for their unique characteristics and wide use in many different applications. Especially, in military networks, all sensor motes are deployed randomly and densely. How can we optimize the number of deployed nodes (sensor node and sink) with a QoS guarantee (minimal end-to...