Doug Suh | Kyung Hee University (original) (raw)

Papers by Doug Suh

Journal of Broadcast Engineering, 2008

The objective of this paper is to provide uninterrupted scalable video streaming to the Cognitive... more The objective of this paper is to provide uninterrupted scalable video streaming to the Cognitive Radio (CR) users by transmitting video frames over multiple channels in hybrid overlay and underlay modes. Since the underlay model is characterized by low power and low bitrate, I-frames of the base layer is an attractive solution. Our contribution is to rank the available spectrum bands based on some parameters such as packet loss, channel capacity, delay, and jitter. Then, the base layer frames as well as the enhancement layer(s) are transmitted without interruption over available high rank spectrum bands. By continues spectrum monitoring, the system creates a descending ranked list of available channels. At the time of arrival of incumbents, the system checks the list and switches to another available spectrum band even with lower rank. Whereas, the I-frames have higher priority, if there is no more channel with acceptable quality, then the I-frames are transmitted in underlay mode. Our simulation results show that the quality of the received video is guaranteed by assuring of I-frame streaming in hybrid mode in compare to pure overlay mode.

IEICE Transactions on Communications, 2011

This paper defines a Quality of Experience (QoE) parameter for multi-view video streaming service... more This paper defines a Quality of Experience (QoE) parameter for multi-view video streaming service over Wireless Broadband Internet, and proposes cross-layer optimization (CLO) algorithm to maximize the QoE. The proposed CLO algorithm interacts with all layers from PHY layer to video layer. Under the time-varying wireless channel condition, it guarantees service continuity to the user by selecting frames to be transmitted. The CLO technique takes interview and the temporal significance of the multi-view video frames into consideration when deciding the Transmission Frame Set (TFS) and its Levels of FEC (LOF). Through simulation of the proposed technique, it is shown that the optimal quality of the multiview video can be achieved even during handover , using the minimum amount of resources. Visual quality of multi-view video streams is improved by about 15.3∼30.2%, especially up to 39.1∼65% during the handover. Moreover, continuity of the most important view has been increased by 20.1∼39.1% in comparison with conventional method.

Electronics Letters, Jun 1, 2016

Moving Picture Expert Group (MPEG) media transport and dynamic adaptive streaming over Hypertext ... more Moving Picture Expert Group (MPEG) media transport and dynamic adaptive streaming over Hypertext Transfer Protocol are compared, which have been standardised by the MPEG for internet-based video services. Their performances as adaptive live streaming systems are evaluated over a deployed long term evolution network. The results provide their operational limitations and optimal operation parameters to improve resource usage and the quality of the users’ experience.

... [4] Amin Shokrollahi, "Raptor codes," IEEE ... Schierl, K. Gänger, C. Hellge, T. St... more ... [4] Amin Shokrollahi, "Raptor codes," IEEE ... Schierl, K. Gänger, C. Hellge, T. Stockhammer, T. Wiegand, SVC-based multisource streaming for robust video transmission in mobile ad hoc ... 6] H. Schwarz, D. Marpe, and T. Wiegand, Overview of the scalable video coding extension ...

Mathematical Problems in Engineering, 2015

In wireless sensor networks, sensor fusion is employed to integrate the acquired data from divers... more In wireless sensor networks, sensor fusion is employed to integrate the acquired data from diverse sensors to provide a unified interpretation. The best and most salient advantage of sensor fusion is to obtain high-level information in both statistical and definitive aspects, which cannot be attained by a single sensor. In this paper, we propose a novel sensor fusion technique based on fuzzy theory for our earlier proposed Cognitive Radio-based Vehicular Ad Hoc and Sensor Networks (CR-VASNET). In the proposed technique, we considered four input sensor readings (antecedents) and one output (consequent). The employed mobile nodes in CR-VASNET are supposed to be equipped with diverse sensors, which cater to our antecedent variables, for example, The Jerk, Collision Intensity, and Temperature and Inclination Degree. Crash Severity is considered as the consequent variable. The processing and fusion of the diverse sensory signals are carried out by fuzzy logic scenario. Accuracy and reliability of the proposed protocol, demonstrated by the simulation results, introduce it as an applicable system to be employed to reduce the causalities rate of the vehicles' crashes.

Interference mitigation is the most important concern in cognitive radio networks because of excl... more Interference mitigation is the most important concern in cognitive radio networks because of exclusive usage right of incumbents on licensed bands. However, to alleviate the issue of spectrum scarcity, secondary users also are allowed to capture the licensed bands in an opportunistic manner without any harmful interference to the primary users. In this paper, we try to rank the available spectrum bands and calculate idle and busy time of licensed channels for secondary usage in order to save precious network resources.

IEEE Transactions on Vehicular Technology, 2021

In this paper, the problem of timing error for free-space optical links with high mobility is inv... more In this paper, the problem of timing error for free-space optical links with high mobility is investigated. In particular, we consider a real scenario in which the sampling clock offset is randomly changing and, in addition, the receiver has no information about the instantaneous channel coefficient as well as instantaneous timing error. Moreover, we consider a general case with signal dependent noise. For the considered scenario, for a conventional receiver with one sampler, we propose an iterative detection method based on the expectation-maximization (EM) algorithm. In the presence of large values of sampling clock offset, shifted error is the dominant error. Hence, in order to reduce the impact of shifted error probability, we propose an iterative data detection method for a receiver which utilizes two shifted samplers. The proposed iterative detection method only requires a series of simple addition and multiplication operation and does not require to solve any integral equations. A set of simulation results are provided to study the system performance for the proposed detection methods. Simulation results demonstrate that for a receiver with two samplers, by using the proposed EM-based detector, we can achieve bit error rate performance very close to the ideal receiver that perfectly knows the instantaneous channel coefficient and sampling clock offset.

Computers, materials & continua, 2021

With the explosive advancements in wireless communications and digital electronics, some tiny dev... more With the explosive advancements in wireless communications and digital electronics, some tiny devices, sensors, became a part of our daily life in numerous elds. Wireless sensor networks (WSNs) is composed of tiny sensor devices. WSNs have emerged as a key technology enabling the realization of the Internet of Things (IoT). In particular, the sensor-based revolution of WSN-based IoT has led to considerable technological growth in nearly all circles of our life such as smart cities, smart homes, smart healthcare, security applications, environmental monitoring, etc. However, the limitations of energy, communication range, and computational resources are bottlenecks to the widespread applications of this technology. In order to tackle these issues, in this paper, we propose an Energy-ef cient Transmission Range Optimized Model for IoT (ETROMI), which can optimize the transmission range of the sensor nodes to curb the hot-spot problem occurring in multi-hop communication. In particular, we maximize the transmission range by employing linear programming to alleviate the sensor nodes' energy consumption and considerably enhance the network longevity compared to that achievable using state-of-the-art algorithms. Through extensive simulation results, we demonstrate the superiority of the proposed model. ETROMI is expected to be extensively used for various smart city, smart home, and smart healthcare applications in which the transmission range of the sensor nodes is a key concern.

The fifth generation (5G) of wireless communication is in its infancy, and its evolving versions ... more The fifth generation (5G) of wireless communication is in its infancy, and its evolving versions will be launched over the coming years. However, according to exposing the inherent constraints of 5G and the emerging applications and services with stringent requirements e.g. latency, energy/bit, traffic capacity, peak data rate, and reliability, telecom researchers are turning their attention to conceptualize the next generation of wireless communications, i.e. 6G. In this paper, we investigate 6G challenges, requirements, and trends. Furthermore, we discuss how artificial intelligence (AI) techniques can contribute to 6G. Based on the requirements and solutions, we identify some new fascinating services and use-cases of 6G, which can not be supported by 5G appropriately. Moreover, we explain some research directions that lead to the successful conceptualization and implementation of 6G.

IEEE Transactions on Vehicular Technology, Jul 1, 2017

Cognitive radio lies among the promising solutions for overcoming the spectrum scarcity problem i... more Cognitive radio lies among the promising solutions for overcoming the spectrum scarcity problem in the forthcoming fifth generation (5G) cellular networks, whereas mobile stations are expected to support multi-mode operations to maintain connectivity to various radio access points. However, for multimedia services particularly, because of the time varying channel capacity, the random arrivals of legacy users, and the on-negligible delay caused by spectrum handoff, it is challenging to achieve seamless streaming leading to minimum QoE degradation. The objective of this paper is to manage spectrum handoff delays, by allocating channels based on the user QoE expectations, minimizing the latency, providing seamless multimedia service and improving QoE. First, to minimize the handoff delays, we use channel usage statistical information to compute channel quality. Based on this, the cognitive base station maintains a ranking index of the available channels to facilitate the cognitive mobile stations. Second, to enhance channel utilization, we develop a priority-based channel allocation scheme to assign channels to the mobile stations based on their QoE requirements. Third, to minimize handoff delays, we employ the hidden Markov model to predict the state of the future time slot. However, due to sensing errors, the scheme proactively performs spectrum sensing and reactively acts handoffs. Forth, we propose a handoff management technique to overcome the interruptions caused by the handoff. In such a way that, when a handoff is predicted, we use scalable video coding to extract the base layer and transmit it during a certain interval time before handoff occurrence to be shown during handoff delays, hence providing seamless service. Our simulation results highlight the performance gain of the proposed framework in terms of channel utilization and received video quality. Index Terms-5G cellular networks, cognitive radio networks, handoff, multimedia communication, quality of experience. I. INTRODUCTION M Obile traffic is experiencing its breakneck proliferation and explosive growth by development of diverse applications, e.g. multimedia services, placing a tremendous strain on wireless communications capacity. Vodafone revealed that its customers used 400 petabytes of data on their mobile phones during August to October 2015, which is on average twice as much 4G data as they did on 3G [1]. The popularity of multimedia applications is the main cause of this growth whereas

대한전자공학회 학술대회, Nov 1, 2013

IEICE Transactions on Information and Systems, 2010

This paper proposes an efficient adaptive depth-map coding scheme for generating virtual-view ima... more This paper proposes an efficient adaptive depth-map coding scheme for generating virtual-view images in 3D-video. Virtual-view images can be generated by view-interpolation based on the decoded depthmap of the image. The proposed depth-map coding scheme is designed to have a new gray-coding-based bit-plane coding method for efficiently coding the depth-map images on the object-boundary areas, as well as the conventional DCT-based coding scheme (H.264/AVC) for efficiently coding the inside area images of the objects or the background depth-map images. Simulation results show that the proposed coding scheme, in comparison with the H.264/AVC coding scheme, improves the BD-rate savings 6.77 %-10.28 % and the BD-PSNR gains 0.42 dB-0.68 dB. It also improves the subjective picture quality of synthesized virtual-view images using decoded depth-maps.

Etri Journal, Oct 10, 2006

Digital broadcasting technology has developed focusing on multi-channel/multi-media, high-definit... more Digital broadcasting technology has developed focusing on multi-channel/multi-media, high-definition quality, and mobility-support. Recently, there has been a clear trend toward bidirectional service with the convergence between broadcasting and communication. The ...

Electronics Letters, Jul 1, 2014

In IEEE 802.11 wireless local area network (WLAN) environments, handovers occur when a mobile nod... more In IEEE 802.11 wireless local area network (WLAN) environments, handovers occur when a mobile node (client) moves from the coverage area of one access point (AP) to that of another AP. In particular, a handover in multimedia streaming settings requires a series of tasks to be executedrecognising the disconnection to the currently associated AP, searching for other APs in client visibility and so on. The time taken to perform these tasks gives rise to an interruption of service for about 6 s, which greatly decreases users' quality of experience (QoE). To reduce service disruptions caused by handovers in IEEE 802.11 networks, a soft proactive handover scheme that exploits the received signal strength indicator (RSSI) and scalable video coding (SVC) is proposed. The proposed scheme predicts the time that a handover process is going to start using the RSSI values and receives the lightweight base layer code of the SVC-encoded video during a certain interval before the predicted handover starts. Experimental results show that the proposed scheme can minimise service interruption times during the 802.11 handover operations, thereby increasing QoE.

2021 IEEE 22nd International Symposium on a World of Wireless, Mobile and Multimedia Networks (WoWMoM), 2021

With the expeditious evolution in technology, recent years have witnessed significant growth in p... more With the expeditious evolution in technology, recent years have witnessed significant growth in passenger assistance applications in the transportation system. Such applications have varying demands for resources and quality of services. This paper presents a Fog computing based transportation system. The system uses multiple Fog devices to provide assistance to the passengers. The passengers and vehicles work as end-users and the Edge devices in the system, respectively. A passenger generates a task and using the Edge device forwards it to the Fog devices for further processing. Selected Fog devices parallel process the fraction of the task, so that the complete task processes within the given time constraint. We use the gamma function based reputation model of Fog devices, which provides the confidence to complete a given task successfully. We present a Knapsack based task offloading algorithm, which helps to fully utilize the resources of the Fog devices. We also present a competitive game model and near Nash Equilibrium solution for estimating the optimal value of the fraction of the task process at Fog devices. Finally, we develop a prototype and present results to investigate the performance of the propose system.

Engineering Applications of Artificial Intelligence, 2021

The Journal of Korea Information and Communications Society, 2014

This paper proposes multi-camera system that relies on 3D views for panoramic video and distribut... more This paper proposes multi-camera system that relies on 3D views for panoramic video and distribution method about panoramic video generation algorithm by using cloud computing. The proposed monitoring system monitors the projected 3D model view, instead of individual 2D views, to detect image distortions. This can minimize compensation errors caused by parallax, thereby improving the quality of the resulting panoramic video. Panoramic video generation algorithm can be divided into registration part and compositing part. Therefore we propose off-loading method of these parts with cloud computing for panoramic video service.

2015 IEEE International Conference on Multimedia & Expo Workshops (ICMEW), 2015

MPEG published a new international standard, MMT (MPEG Media Transport) for efficient transport o... more MPEG published a new international standard, MMT (MPEG Media Transport) for efficient transport of MPEG media over all IP networks in June 2014. This paper shows its potential as standard for adaptive media service system. We applied this standard to video streaming system and shows its efficiency transmission in limited resource network environment. The system has been tested in harsh condition such as simulated mobile channels.