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The ever increasing demand for higher data rate and increased bandwidth has pushed radio frequency spectrum towards congestion. To fulfill this demand, a natural extension is towards the exploration of optical spectrum for communication. Fueled by mass adaptation of light emitting diodes (LEDs) for illumination purposes, mainly due to its energy efficient properties and high frequency switching characteristics, a new type of communication has emerged known as visible light communication (VLC). Recently, VLC has gained much attention not only for its utilization in indoor positioning and localization applications, but also it is paving the way towards outdoor applications related to intelligent transportation systems (ITS). Despite VLC's popularity as a complementary communication technology, it faces many challenges including the low data rate, limited communication distance and robustness to interference, specifically in multi-user environment representing real-world scenarios. Much work has been done to increase the data rate, however very few works found in literature deal with increasing the robustness and communication distance of a VLC link, both of which are critical parameters due to the visible nature of the link. In this work, we propose to address these challenges in four phases. In the first phase, we propose a polarization based transceiver methodology to mitigate channel interference thereby increasing the robustness of the optical link. Experimental results demonstrate a 32.6% more robust VLC link compared to the conventional transceiver under severe optical interference. In the next phase, we extend the work to support for multi transmitter environment. With additional capabilities of spatially separating interference sources, image sensor based VLC receivers have been studied. The main challenges include evaluation of shutter speed imposing restrictions on minimum SNR requirement of the transmitter and variable frame rate phenomenon resulting i

This work presents channel approximation for a camera communication (Cam-Com)link using perspective projection model with complete intrinsic parameterization. The accuracy of the model is demonstrated by exploiting spatial separation characteristics of the output image. © 2018 OSA.

This work demonstrates a record 160 m long visible light communication (VLC) link using LED transmitters and an image sensor-based receiver, for distance-critical applications. This marks the longest VLC distance achieved to date, using a combination of novel modulation technique at the transmitter and an undersampling-based receiver incorporating adaptive threshold decisioning. Experimental results demonstrate low bit error rate (BER) performance at the achieved communication distance.

The ever increasing demand for higher data rate and increased bandwidth has pushed radio frequency spectrum towards congestion. To fulfill this demand, a natural extension is towards the exploration of optical spectrum for communication. Fueled by mass adaptation of light emitting diodes (LEDs) for illumination purposes, mainly due to its energy efficient properties and high frequency switching characteristics, a new type of communication has emerged known as visible light communication (VLC). Recently, VLC has gained much attention not only for its utilization in indoor positioning and localization applications, but also it is paving the way towards outdoor applications related to intelligent transportation systems (ITS). Despite VLC's popularity as a complementary communication technology, it faces many challenges including the low data rate, limited communication distance and robustness to interference, specifically in multi-user environment representing real-world scenarios. Much work has been done to increase the data rate, however very few works found in literature deal with increasing the robustness and communication distance of a VLC link, both of which are critical parameters due to the visible nature of the link. In this work, we propose to address these challenges in four phases. In the first phase, we propose a polarization based transceiver methodology to mitigate channel interference thereby increasing the robustness of the optical link. Experimental results demonstrate a 32.6% more robust VLC link compared to the conventional transceiver under severe optical interference. In the next phase, we extend the work to support for multi transmitter environment. With additional capabilities of spatially separating interference sources, image sensor based VLC receivers have been studied. The main challenges include evaluation of shutter speed imposing restrictions on minimum SNR requirement of the transmitter and variable frame rate phenomenon resulting i

This work presents channel approximation for a camera communication (Cam-Com)link using perspective projection model with complete intrinsic parameterization. The accuracy of the model is demonstrated by exploiting spatial separation characteristics of the output image. © 2018 OSA.

This work demonstrates a record 160 m long visible light communication (VLC) link using LED transmitters and an image sensor-based receiver, for distance-critical applications. This marks the longest VLC distance achieved to date, using a combination of novel modulation technique at the transmitter and an undersampling-based receiver incorporating adaptive threshold decisioning. Experimental results demonstrate low bit error rate (BER) performance at the achieved communication distance.

This work demonstrates a record 160 m long visible light communication (VLC) link using LED transmitters and an image sensor-based receiver, for distance-critical applications. This marks the longest VLC distance achieved to date, using a combination of novel modulation technique at the transmitter and an undersampling-based receiver incorporating adaptive threshold decisioning. Experimental results demonstrate low bit error rate (BER) performance at the achieved communication distance.

The ever increasing demand for higher data rate and increased bandwidth has pushed radio frequency spectrum towards congestion. To fulfill this demand, a natural extension is towards the exploration of optical spectrum for communication. Fueled by mass adaptation of light emitting diodes (LEDs) for illumination purposes, mainly due to its energy efficient properties and high frequency switching characteristics, a new type of communication has emerged known as visible light communication (VLC). Recently, VLC has gained much attention not only for its utilization in indoor positioning and localization applications, but also it is paving the way towards outdoor applications related to intelligent transportation systems (ITS). Despite VLC's popularity as a complementary communication technology, it faces many challenges including the low data rate, limited communication distance and robustness to interference, specifically in multi-user environment representing real-world scenarios. Much work has been done to increase the data rate, however very few works found in literature deal with increasing the robustness and communication distance of a VLC link, both of which are critical parameters due to the visible nature of the link. In this work, we propose to address these challenges in four phases. In the first phase, we propose a polarization based transceiver methodology to mitigate channel interference thereby increasing the robustness of the optical link. Experimental results demonstrate a 32.6% more robust VLC link compared to the conventional transceiver under severe optical interference. In the next phase, we extend the work to support for multi transmitter environment. With additional capabilities of spatially separating interference sources, image sensor based VLC receivers have been studied. The main challenges include evaluation of shutter speed imposing restrictions on minimum SNR requirement of the transmitter and variable frame rate phenomenon resulting i

This work presents channel approximation for a camera communication (Cam-Com)link using perspective projection model with complete intrinsic parameterization. The accuracy of the model is demonstrated by exploiting spatial separation characteristics of the output image. © 2018 OSA.

Recently, camera communication (CamCom) has emerged as a viable candidate for realizing complementary communication technology in driver assistance applications related to intelligent transportation systems (ITS). Under-sampling based CamCom links have been proposed before [1-2]. However, they impose restrictions on the minimum signal-to-noise ratio (SNR) requirement of the transmitter due to receiver sampling at fast shutter speeds. Moreover, they do not consider the variable frame rate phenomenon of the camera, which can drastically affect the bit error rate (BER) performance of the system. In this work, we propose and implement a novel modulation scheme that not only supports low-SNR transmitters but also minimizes the effect of variable frame rate on the BER of the system. © 2018 OSA - The Optical Society. All rights reserved.

This work presents a model for channel length estimation of a multiple-input-multiple-output camera communication link, based upon perspective projection modeling. Perspective projection model provides accurate mapping compared with conventional pin-hole approximation, due to the inclusion of additional intrinsic parameters. Simulations were carried out using the proposed model and a strong correlation was demonstrated through experimental results, thereby validating the proposed channel length estimation model.

Under-sampled camera communication (CamCom) systems realized using fast shutter speeds limit the communication channel length and impose restrictions on the minimum signal-to-noise ratio (SNR) requirement of LED based transmitters. In this paper, we present an empirical model to estimate the effective channel length of a CamCom system. Based upon the model, a transceiver methodology is proposed and demonstrated to support low-SNR transmitters, thereby increasing the effective communication distance of an under-sampled CamCom link. Moreover, an adaptive threshold decoding technique is presented to make the system robust against the variable frame rate phenomenon. The proposed methodology can be utilized to increase the communication distance of under-sampled CamCom links for infrastructure-to-vehicle communication employing low-SNR transmitters.

This work presents channel approximation for a camera communication (Cam-Com) link using perspective projection model with complete intrinsic parameterization. The accuracy of the model is demonstrated by exploiting spatial separation characteristics of the output image.

One of the main challenges in establishing a robust visible light communication (VLC) link is to prevent optical interference produced by other light sources from corrupting the signal. Previous solutions catering for this issue assume that optical interference and the signal operate in nonoverlapping frequency bands. This paper presents an innovative transceiver architecture for establishing a frequency-independent interference-tolerant VLC link. The transmitter exploits the polarization property of light to transmit differential signals over adjacent channels, and the receiver utilizes differential amplification in conjunction with polarization to implement a common noise rejection technique. The implemented system demonstrated a 32.6% more robust VLC link compared to the conventional transceiver under severe optical interference.

Recently, camera communication (CamCom) has emerged as a viable candidate for realizing complementary communication technology in driver assistance applications related to intelligent transportation systems (ITS). Under-sampling based CamCom links have been proposed before [1-2]. However, they impose restrictions on the minimum signal-to-noise ratio (SNR) requirement of the transmitter due to receiver sampling at fast shutter speeds. Moreover, they do not consider the variable frame rate phenomenon of the camera, which can drastically affect the bit error rate (BER) performance of the system. In this work, we propose and implement a novel modulation scheme that not only supports low-SNR transmitters but also minimizes the effect of variable frame rate on the BER of the system. © 2018 OSA - The Optical Society. All rights reserved.

This work presents a model for channel length estimation of a multiple-input-multiple-output camera communication link, based upon perspective projection modeling. Perspective projection model provides accurate mapping compared with conventional pin-hole approximation, due to the inclusion of additional intrinsic parameters. Simulations were carried out using the proposed model and a strong correlation was demonstrated through experimental results, thereby validating the proposed channel length estimation model.

This work presents channel approximation for a camera communication (Cam-Com) link using perspective projection model with complete intrinsic parameterization. The accuracy of the model is demonstrated by exploiting spatial separation characteristics of the output image.

Under-sampled camera communication (CamCom) systems realized using fast shutter speeds limit the communication channel length and impose restrictions on the minimum signal-to-noise ratio (SNR) requirement of LED based transmitters. In this paper, we present an empirical model to estimate the effective channel length of a CamCom system. Based upon the model, a transceiver methodology is proposed and demonstrated to support low-SNR transmitters, thereby increasing the effective communication distance of an under-sampled CamCom link. Moreover, an adaptive threshold decoding technique is presented to make the system robust against the variable frame rate phenomenon. The proposed methodology can be utilized to increase the communication distance of under-sampled CamCom links for infrastructure-to-vehicle communication employing low-SNR transmitters.

One of the main challenges in establishing a robust visible light communication (VLC) link is to prevent optical interference produced by other light sources from corrupting the signal. Previous solutions catering for this issue assume that optical interference and the signal operate in nonoverlapping frequency bands. This paper presents an innovative transceiver architecture for establishing a frequency-independent interference-tolerant VLC link. The transmitter exploits the polarization property of light to transmit differential signals over adjacent channels, and the receiver utilizes differential amplification in conjunction with polarization to implement a common noise rejection technique. The implemented system demonstrated a 32.6% more robust VLC link compared to the conventional transceiver under severe optical interference.

Recently, camera communication (CamCom) has emerged as a viable candidate for realizing complementary communication technology in driver assistance applications related to intelligent transportation systems (ITS). Under-sampling based CamCom links have been proposed before [1-2]. However, they impose restrictions on the minimum signal-to-noise ratio (SNR) requirement of the transmitter due to receiver sampling at fast shutter speeds. Moreover, they do not consider the variable frame rate phenomenon of the camera, which can drastically affect the bit error rate (BER) performance of the system. In this work, we propose and implement a novel modulation scheme that not only supports low-SNR transmitters but also minimizes the effect of variable frame rate on the BER of the system. © 2018 OSA - The Optical Society. All rights reserved.

This work presents a model for channel length estimation of a multiple-input-multiple-output camera communication link, based upon perspective projection modeling. Perspective projection model provides accurate mapping compared with conventional pin-hole approximation, due to the inclusion of additional intrinsic parameters. Simulations were carried out using the proposed model and a strong correlation was demonstrated through experimental results, thereby validating the proposed channel length estimation model.

This work presents channel approximation for a camera communication (Cam-Com) link using perspective projection model with complete intrinsic parameterization. The accuracy of the model is demonstrated by exploiting spatial separation characteristics of the output image.

Under-sampled camera communication (CamCom) systems realized using fast shutter speeds limit the communication channel length and impose restrictions on the minimum signal-to-noise ratio (SNR) requirement of LED based transmitters. In this paper, we present an empirical model to estimate the effective channel length of a CamCom system. Based upon the model, a transceiver methodology is proposed and demonstrated to support low-SNR transmitters, thereby increasing the effective communication distance of an under-sampled CamCom link. Moreover, an adaptive threshold decoding technique is presented to make the system robust against the variable frame rate phenomenon. The proposed methodology can be utilized to increase the communication distance of under-sampled CamCom links for infrastructure-to-vehicle communication employing low-SNR transmitters.

One of the main challenges in establishing a robust visible light communication (VLC) link is to prevent optical interference produced by other light sources from corrupting the signal. Previous solutions catering for this issue assume that optical interference and the signal operate in nonoverlapping frequency bands. This paper presents an innovative transceiver architecture for establishing a frequency-independent interference-tolerant VLC link. The transmitter exploits the polarization property of light to transmit differential signals over adjacent channels, and the receiver utilizes differential amplification in conjunction with polarization to implement a common noise rejection technique. The implemented system demonstrated a 32.6% more robust VLC link compared to the conventional transceiver under severe optical interference.