Go to the main menu
Skip to content
Go to bottom
REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
The Journal of The Institute of Internet, Broadcasting and Communication
Journal Basic Information
Journal DOI :
The institute Of Webcasting, Internet And Telecommunication
Editor in Chief :
Volume & Issues
Volume 13, Issue 6 - Dec 2013
Volume 13, Issue 5 - Oct 2013
Volume 13, Issue 4 - Aug 2013
Volume 13, Issue 3 - Jun 2013
Volume 13, Issue 2 - Apr 2013
Volume 13, Issue 1 - Feb 2013
Selecting the target year
Implementation of Integrated Controller of ACC/LKS based on OSEK OS
Choi, Dan-Bee ; Lee, Kyung-Jung ; Ahn, Hyun-Sik ;
The Journal of The Institute of Internet, Broadcasting and Communication, volume 13, issue 5, 2013, Pages 1~8
DOI : 10.7236/JIIBC.2013.13.5.1
This paper implements an integrated vehicle chassis system of ACC(Adaptive Cruise Control) and LKS(Lane Keeping System) based on OSEK OS to vehicle operating system and analyzes its performance through experiments. In recent years active safety and advanced driver assistance system has discussed to improve safety of vehicle. Among the rest, We integrate ACC that controls longitudinal velocity of vehicle and LKS that assists a vehicle in maintaing its driving lane, then implement integrated control system in vehicle. Implemented control system uses OSEK/VDX proposed standard, which is aiming at reusability and safety of software for vehicle and removal hardware dependence of application software. Redesigned control system based on OSEK OS, which is supported by OSEK/VDX, can manage real-time task, process interrupt and manage shared resource. We show by results performed EILS(ECU-In-the-Loop Simulation) that OSEK OS-based integrated controller of ACC and LKS is equivalent conventional integrated controller of ACC and LKS.
Smart Mobile Blackbox DVR in Car Environment
Choi, Sun-O ; Kim, Young-Po ; Im, Yong-Soon ; Kim, Young-Ja ; Kang, Eun-Young ;
The Journal of The Institute of Internet, Broadcasting and Communication, volume 13, issue 5, 2013, Pages 9~15
DOI : 10.7236/JIIBC.2013.13.5.9
In this paper, automatic recognition of an accident and whether service delivery and risk driving through the giving of the driver to correct driving habits before and after the accident to reproduce highly scalable video Smart Mobile Blackbox DVR (SMBD, Smart Mobile Blackbox DVR) Computer of the model was designed. SMBD on embedded systems equipped with wireless capabilities to sleep in the car accident point and the image information by wireless communications, by notification in the control center, 24-hour emergency rescue service and traffic information can be provided. The vehicle ECU (Electronic Control Unit) of the vehicle information and sensor data in conjunction with wireless eCall (Emergency Call) services can be realized.
A study on improvement of ISO/IEC 29157 MAC protocol
Cha, Bong-Sang ; Jeong, Eui-Hoon ; Jeon, Gwangil ; Seo, Dae-Young ;
The Journal of The Institute of Internet, Broadcasting and Communication, volume 13, issue 5, 2013, Pages 17~26
DOI : 10.7236/JIIBC.2013.13.5.17
ISO/IEC 29157 originally developed in the Republic of Korea and is based on commercially available PicoCast v1.0. ISO/IEC JTC1 SC6 was registered by the international standard on May 2010. A single platform for a variety of applications and media formats to support development objectives were. ISO/IEC 29157 based wireless networks, ie, Pico-net to master node periodically transmit sync signal is synchronized to the number of slave nodes have the communications structure. Pico-net also supports a variety of network topologies and direct communication between nodes(single-hop communication) and QoS is guaranteed. But Pico-net network structure has the following problems. Loss of communication problems due to mobile nodes, resulting in limitations of node mobility and wireless network operation range of conventional wireless networks operating range less than 1/4 was reduced to the problem. In this paper, a possible solution to the problems mentioned is proposed, using multi-hop communication technology and sync signal transmission technology between nodes.
Automatic Retrieval of SNS Opinion Document Using Machine Learning Technique
Chang, Jae-Young ;
The Journal of The Institute of Internet, Broadcasting and Communication, volume 13, issue 5, 2013, Pages 27~35
DOI : 10.7236/JIIBC.2013.13.5.27
Recently, as Social Network Services(SNS) are becoming more popular, much research has been doing on analyzing public opinions from SNS. One of the most important tasks for solving such a problem is to separate opinion(subjective) documents from others(e.g. objective documents) in SNS. In this paper, we propose a new method of retrieving the opinion documents from Twitter. The reason why it is not easy to search or classify the opinion documents in Twitter is due to a lack of publicly available Twitter documents for training. To tackle the problem, at first, we build a machine-learned model for sentiment classification using the external documents similar to Twitter, and then modify the model to separate the opinion documents from Twitter. Experimental results show that proposed method can be applied successfully in opinion classification.
A Study on Research Trends of Graph-Based Text Representations for Text Mining
Chang, Jae-Young ;
The Journal of The Institute of Internet, Broadcasting and Communication, volume 13, issue 5, 2013, Pages 37~47
DOI : 10.7236/JIIBC.2013.13.5.37
Text Mining is a research area of retrieving high quality hidden information such as patterns, trends, or distributions through analyzing unformatted text. Basically, since text mining assumes an unstructured text, it needs to be represented as a simple text model for analyzing it. So far, most frequently used model is VSM(Vector Space Model), in which a text is represented as a bag of words. However, recently much researches tried to apply a graph-based text model for representing semantic relationships between words. In this paper, we survey research trends of graph-based text representation models for text mining. Additionally, we also discuss about future models of graph-based text mining.
A Burst-mode Optical Receiver for 1.25Gbps PON
Ki, Hyeon-Cheol ;
The Journal of The Institute of Internet, Broadcasting and Communication, volume 13, issue 5, 2013, Pages 49~54
DOI : 10.7236/JIIBC.2013.13.5.49
We designed a burst mode optical receiver for 1.25Gbps PON(Passive Optical Network), fabricated it using
BiCMOS foundry. We minimized the loss of the data in the front of the burst by reducing AGC(Automatic Gain Control) signal generation time using an exponential amplifier. We confirmed that AGC of the burst mode optical receiver functioned well and showed good performance in measurement. However, although the eye of the eye pattern was opened the jitter characteristic was deteriorated due to the heavy waveform distortion.
Localization of primary user for cognitive radios based on estimation of path-loss exponent
Anh, Hoang ; Koo, Insoo ;
The Journal of The Institute of Internet, Broadcasting and Communication, volume 13, issue 5, 2013, Pages 55~63
DOI : 10.7236/JIIBC.2013.13.5.55
In cognitive radio networks, acquirement of position information of primary user is very important to secondary network since localization information of primary users can be utilized for improving the spectrum efficiency of secondary network and for avoiding harmful interference to primary users by using proper power control. Among various location methods, Received Signal Strength (RSS)-based localization has been widely used for distance measurements in the location detection process despite its inherent inaccuracy because it can be easily implemented without any additional hardware cost. In the RSS-based localization, the distance is measured by the received signal strength, and distance error can be caused by many factors such as fading, shadowing and obstacle between two nodes. In the paper, therefore we propose a localization scheme based on estimation of path-loss exponent to localize the location of primary users more accurately. Through simulations, it is shown that the proposed scheme can provide less localization error and interference rate to primary users than other schemes.
Energy Efficiency of Cooperative Routing with EGC Over Rayleigh Fading Channel
Kong, Hyung-Yun ; Tran, Truc Thanh ;
The Journal of The Institute of Internet, Broadcasting and Communication, volume 13, issue 5, 2013, Pages 65~70
DOI : 10.7236/JIIBC.2013.13.5.65
In this paper, we propose a multi-hop cooperative transmission protocol to obtain energy savings in static wireless networks. Each terminal in the network is equipped with a single antenna and each receiver uses equal gain combining technique (EGC) to combine received signals. We also propose a power allocation strategy which optimizes the total transmit power at each stage. Monte-Carlo simulations are presented to evaluate and compare performance of the proposed protocol with the multi-hop direct transmission (MDT) and the cooperative routing protocol proposed by Khadani , in terms of the average total transmit power and the average number of required stages.
A Method Using Selection-Combining To Enhance Spectrum Sensing Performance
Kong, Hyung-Yun ; Tran, Truc Thanh ;
The Journal of The Institute of Internet, Broadcasting and Communication, volume 13, issue 5, 2013, Pages 71~76
DOI : 10.7236/JIIBC.2013.13.5.71
This paper considers an approach of secondary user selection method in cooperative spectrum sensing, which two users with the best SNR in sensing channel and in reporting channel, respectively, are selected to cooperate with each other in the spectrum sensing. The sensing results reported by two users are then combined to detect PU signal operation. A comparison between this proposed method with conventional selection technique in which only the user having the best sensing channel SNR is selected shows that the proposed method outperforms. We make an assumption that sensing channels experience identical, independent distributed (i.i.d) Rayleigh fading and the reporting channels are invariant and non-identical. Simulation results are derived for demonstration.
Information System of Smart u-LED Lighting Energy based on Zigbee Mesh Network
Kim, Sam-Taek ;
The Journal of The Institute of Internet, Broadcasting and Communication, volume 13, issue 5, 2013, Pages 77~83
DOI : 10.7236/JIIBC.2013.13.5.77
Nowadays, the limitation of Lighting control and management skills is the excessive cost of equipments, the operational difficulties and wasting energy. To solve this problem is in need of communication and management S/W that is worked out complexly well as a information system of smart lighting energy, which is loaded wireless network facility. This paper made a study od the energy saving technology through energy monitoring and we developed LEIS(Lighting Energy Information Sysem) to converge this one. LEIS is monitoring and control lighting energy data that is collelcted from sensors by Zigbee mesh network and shows lighting use information by visualization to users. It is consists of lighting energy information data base based on LEM(Lighting Energy Metering) information and LEIS Web application, provide function scenario to manage energy optimization through LEIS.
A Study on the Relative Positioning Technology based on Range Difference and Root Selection
Oh, Jongtaek ;
The Journal of The Institute of Internet, Broadcasting and Communication, volume 13, issue 5, 2013, Pages 85~91
DOI : 10.7236/JIIBC.2013.13.5.85
For location based service and context awareness services, accurate indoor positioning technology is essential. The TDOA method that uses the range difference between signal source and receivers for estimating the location of the signal source, has estimation error due to measurement error. In this paper, a new algorithm is proposed to select the real root among calculated roots using the range difference information, and the estimated position of the signal source shows good accuracy compared to the existing method.
MIWF: Message Inter-Working Framework to Connect Rich Communication Service Messages and SMS Messages
Lee, Dongcheul ;
The Journal of The Institute of Internet, Broadcasting and Communication, volume 13, issue 5, 2013, Pages 93~99
DOI : 10.7236/JIIBC.2013.13.5.93
We have used SMS to exchange messages between mobile phones. Since the network evolved to the ALL-IP network, the next generation messaging service, RCS, has emerged to the market. Because SMS and RCS coexist, we need to inter-work the messages between SMS users and RCS users. This paper introduces a message inter-working framework(MIWF) that can inter-work SMS and RCS without changing end user's UX. It defines the call flows between the network equipment and MIWF. Also, it shows how MIWF converts messages between 3 protocols. Performance evaluation proves that MIWF does not add loads to the existing network.
QoS Functions in Mobile Backhaul Network
Park, Chun-Kwan ;
The Journal of The Institute of Internet, Broadcasting and Communication, volume 13, issue 5, 2013, Pages 101~105
DOI : 10.7236/JIIBC.2013.13.5.101
This paper addresses QoS functions in mobile backhaul network to accommodate the diverse traffics in cell site. The traffics assigned to the switching function in RAN system, such as Ethernet frame, IP packet, and ATM cell, are segmented, and then encapsulated to transfer then to the mobile backhaul network. ISP can converge all generation traffics, such as voice, HSPA, over all-IP RAN through standard pseudowire encapsulation. These can be enhanced with diverse QoS methods as well as comprehensive monitoring and diagnostic capabilities. Therefore in this paper, QoS functions under theses operations is simulated according to the encapsulation functions.
Authentication eXtention Scheme of Fast Handover for Secure NEMO-based PMIPv6 Networks
Im, Illkyun ; Jeong, Jongpil ;
The Journal of The Institute of Internet, Broadcasting and Communication, volume 13, issue 5, 2013, Pages 107~119
DOI : 10.7236/JIIBC.2013.13.5.107
This paper reinforced security under the network evaluation of wire wireless integration of NEMO (NEwork MObility) supporting mobility and network-based PMIPv6 (Proxy Mobile IPv6). It also proposes
(Symmetric Key-Based Local-Lighted Authentication Scheme) based on simple key which reduces code calculation and authentication delay costs. Moreover, fast handover technique was also adopted to reduce handover delay time in PMIPv6 and X-FPMIPv6 (eXtension of Fast Handover for PMIPv6) was used to support global mobility. In addition, AX-FPMIPv6 (Authentication eXtension of Fast Handover for PMIPv6) is proposed which integrated
and X-FPMIPv6 by applying Piggybacks method to reduce the overhead of authentication and signaling. The AX-FPMIPv6 technique suggested in this paper shows that this technique is better than the existing schemes in authentication and handover delay according to the performance analysis.
Performance Analysis of Fast Handover Scheme Based on Secure Smart Mobility in PMIPv6 Networks
Yoon, KyoungWon ; Jeong, Jongpil ;
The Journal of The Institute of Internet, Broadcasting and Communication, volume 13, issue 5, 2013, Pages 121~133
DOI : 10.7236/JIIBC.2013.13.5.121
Defect-free transfer service on the Next-generation wireless network extensive roaming mobile node (MN) to provide efficient mobility management has become very important. MIPv6(Mobility IPv6) is one of mobility management scheme proposed by IETF(Internet Engineering Task Force), and IPv6-based mobility management techniques have been developed in various forms. One of each management techniques, IPv6-based mobility management techniques for PMIPv6 (MIPv6) system to improve the performance of a variety of F-PMIPv6 (Fast Handover for Proxy MIPv6) is proposed. However, the F-PMIPv6 is cannot be excellent than PMIPv6 in all scenarios. Therefor, to select a proper mobility management scheme between PMIPv6 and F-PMIPv6 becomes an interesting issue, for its potenrials in enhancing the capacity and scalability of the system. In this paper, we develop an analytical model to analyze the applicability of PMIPv6 and F-PMIPv6. Based on this model, we design an Secure Smart Mobility Support(SSM) scheme that selects the better alternative between PMIPv6 and F-PMIPv6 for a user according to its changing mobility and service characteristics. When F-PMIPv6 is adopted, SSM chooses the best mobility anchor point and regional size to optimize the system performance. Numerical results illustrate the impact of some key parameters on the applicability of PMIPv6 and F-PMIPv6. Finally, SSM has proven even better result than PMIPv6 and F-PMIPv6.
Design of a Smart Phone App for Measuring Object Size in a Picture Image
Oh, Sun-Jin ;
The Journal of The Institute of Internet, Broadcasting and Communication, volume 13, issue 5, 2013, Pages 135~142
DOI : 10.7236/JIIBC.2013.13.5.135
With a rapid growth of hardware and product material industries, evolution of handheld terminal technologies is progressed. Various applications using mobile phone are the major trend in recent smart applications. Especially, interesting applications using camera module in a smartphone are developed continuously, mobile users are able to use various useful mobile applications nowadays. In this paper, we design and implement smartphone app for measuring real size of the shooting object in the image taken by a camera module in a smartphone precisely. We implement 4 different shooting modes for precise measurement of objects and 0 point control module is developed to minimize the differences of shooting images taken by different types and systems of various smartphones. The smartphone app proposed and implemented in this paper is analyzed and evaluated by a simulation study.
Implementation of Polarization Beam-Splitter based on DFB-Assisted Plasmonic Multimode Interference Coupler
Ho, Kwang-Chun ;
The Journal of The Institute of Internet, Broadcasting and Communication, volume 13, issue 5, 2013, Pages 143~148
DOI : 10.7236/JIIBC.2013.13.5.143
A novel ultracompact polarization beam-splitter (PBS) combining two plasmonic multimode interference couplers (P-MMICs) and DFB guiding structure is implemented. The
P-MMICs are designed to collect the polarized powers of TE and TM modes reflected by or transmitted through an internal DFB structure. The simulation results show that the designed DFB-assisted PBS is very short (about
), and has a low insertion loss, a high extinction ratio, and a broad bandwidth of 20 nm.
Development of Urban Farm Management System using Commercial SNS as IoT Platform
Ryu, Dae-Hyun ;
The Journal of The Institute of Internet, Broadcasting and Communication, volume 13, issue 5, 2013, Pages 149~154
DOI : 10.7236/JIIBC.2013.13.5.149
IoT is emerging topic of the post-smartphone era. But IoT service is actually not easy but due to the absence of the open standard IoT service platform. In this study, We propose and implement IoT services platform using commercial SNS platform like Tweet, Facebook or YouTube. we implement the intelligent control system of the urban farm using our IoT services platform as an example. Our system can save an additional server deployment and management cost using open SNS platform like Tweet or Facebook or Youtube. In addition, there are needs to develop App. for the smartphone because we can take advantage of the user interface which is developed by global enterprises.
Design and Implementation of Bridge Information System using Smart Phone
Lee, Hwa-Min ; Choi, Sung-Jai ;
The Journal of The Institute of Internet, Broadcasting and Communication, volume 13, issue 5, 2013, Pages 155~161
DOI : 10.7236/JIIBC.2013.13.5.155
This paper presented an augmented reality based mobile application of maintenance and management for concrete bridges. For the development of augmented reality system, it was necessary to establish the concrete bridges detail information and history of maintenance that build the database of those. Also, the augmented reality based system required that concrete bridge information presented by the mobile smart phone. Therefore, this study developed an augmented reality based concrete bridge information mobile application-All about Bridge based on android smart phone and smart pad. The proposed All about Bridge application supports a various bridge informations simultaneously using smart phone and augmented reality technology.
Assignment Problem Algorithm Based on the First Selection Method of the Minimum Cost
Lee, Sang-Un ;
The Journal of The Institute of Internet, Broadcasting and Communication, volume 13, issue 5, 2013, Pages 163~171
DOI : 10.7236/JIIBC.2013.13.5.163
This paper proposes an algorithm that seeks the optimal solution for an assignment problem through a simplified process. Generally it is Hungarian algorithm that is prevalently used to solve a given assignment problem. The proposed algorithm reduces 4 steps Hungarian algorithm into 2 steps. Firstly, the algorithm selects the minimum cost from a matrix and deletes the rest of the rows and columns. Secondly, it improves on the solution through reassignment process. For 27 balanced assignment problems and 7 unbalanced problems, the proposed algorithm has successfully yielded the optimal solution, which Genetic algorithm has failed. This algorithm is thus found to be an appropriate replacement of Hungarian algorithm.
Simple Solution for Multi-commodity Transportation Problem
Lee, Sang-Un ; Choi, Myeong-Bok ;
The Journal of The Institute of Internet, Broadcasting and Communication, volume 13, issue 5, 2013, Pages 173~181
DOI : 10.7236/JIIBC.2013.13.5.173
This paper proposes a heuristic optimal solution of multicommodity transportation problem. The proposed algorithm has 3 steps. First the proposed algorithm transforms multicommodity transshipment problem to a general transportation problem, but if the problem is a multicommodity transportation problem, it is not transformed. And the multicommodity is disassembled to a single commodity. Second if it is a multicommodity transportation problem, the algorithm selects the minimum cost according to commodity, on the other hand if it is a multicommodity transshipment problem, the algorithm directly selects the minimum cost based on demand area. And the algorithm assigns carloadings to be satisfied the supply and demand quantity. The algorithm repeats these processes until a given demand quantity is satisfied. Last if it has a condition that is able to reduce the transportation expense, the proposed algorithm controls the assignment quantity of the initial value that got from the step 2. The proposed algorithm was applied to two multicommodity transportation problem and three multicommodity transshipment problem and it got more good result than an existing linear programming method.
lustering of Categorical Data using Rough Entropy
Park, Inkyoo ;
The Journal of The Institute of Internet, Broadcasting and Communication, volume 13, issue 5, 2013, Pages 183~188
DOI : 10.7236/JIIBC.2013.13.5.183
A variety of cluster analysis techniques prerequisite to cluster objects having similar characteristics in data mining. But the clustering of those algorithms have lots of difficulties in dealing with categorical data within the databases. The imprecise handling of uncertainty within categorical data in the clustering process stems from the only algebraic logic of rough set, resulting in the degradation of stability and effectiveness. This paper proposes a information-theoretic rough entropy(RE) by taking into account the dependency of attributes and proposes a technique called min-mean-mean roughness(MMMR) for selecting clustering attribute. We analyze and compare the performance of the proposed technique with K-means, fuzzy techniques and other standard deviation roughness methods based on ZOO dataset. The results verify the better performance of the proposed approach.
Design of Social Learning Platform for Collaborative Study
Cho, Byung-Ho ;
The Journal of The Institute of Internet, Broadcasting and Communication, volume 13, issue 5, 2013, Pages 189~194
DOI : 10.7236/JIIBC.2013.13.5.189
Social learning is a new study model of future knowledge information society. In different existing study, it lay stress on individual activity and collaborative study with others. It is useful to apply social media services to build social learning platform for collaborative study. In my paper, after existing social media services and social platforms are investigated and analyzed, an effective social learning platform applyng social media services is presented. Also differences and superiority compared to other social platforms is presented through new social learning platform architecture and screen design.
Implementation of Secured Smart-Learning System using Encryption Function
Yang, J.S. ; Hong, Y.S. ; Yoon, E.J. ; Choi, Y.J. ; Chun, S.K. ;
The Journal of The Institute of Internet, Broadcasting and Communication, volume 13, issue 5, 2013, Pages 195~201
DOI : 10.7236/JIIBC.2013.13.5.195
The government has invested much budget for 5years to do the Smart-education and operate digital textbook services since 2011. The private enterprises also decided to focus on constructing Smart learning system by investing much budget. If these systems are constructed nationwide and therefore can access to cyber university by using smart devices, we can reduce the information gap and study online lectures to get a grade whenever, whoever and wherever we want to. However, these convenient systems can cause serious problems like falsifying grades by hacking if security systems are weak. In this paper, we formulated cyber university which is secured in terms of security. For this, we simulated the smart-learning system which strengthened the security, considering code algorithm and encryption technique.
Double Talk Detection before the Convergence of Echo Canceller
Yoo, Jae-Ha ; Kim, Soo-Chan ; Kim, Dong-Yon ;
The Journal of The Institute of Internet, Broadcasting and Communication, volume 13, issue 5, 2013, Pages 203~208
DOI : 10.7236/JIIBC.2013.13.5.203
In this paper, we proposed a performance improvement method of the double talk detector which can operate before the echo canceller converges. Microphone input signal is filtered by the linear prediction filter and this filtered signal is used for detection. The coefficients of the linear prediction filter are given by the far-end talker signal. During single talk, filtered signal has low power since the characteristics of the echo signal is similar with those of the far-end talker signal. But, during double talk, the filtered signal does not have low power because the signal of different characteristics is included in the microphone signal. Double talk is detected by this difference. Simulations using real speech signals verified that the proposed method outperformed the conventional methods.
Reduction of Authentication Cost Based on Key Caching for Inter-MME Handover Support
Hwang, Hakseon ; Jeong, Jongpil ;
The Journal of The Institute of Internet, Broadcasting and Communication, volume 13, issue 5, 2013, Pages 209~220
DOI : 10.7236/JIIBC.2013.13.5.209
Handover is the technology to minimize data lose of mobile devices and make continuous communication possible even if the device could be moved from one digital cell site to another one. That is, it is a function that enables the mobile user to avoid the disconnection of phone conversations when moving from a specific mobile communication area to another. Today, there are a lot of ongoing researches for fast and efficient hand-over, in order to address phone call's delay and disconnection which are believed to be the mobile network's biggest problems, and these should essentially be resolved in all mobile networks. Thanks to recent technology development in mobile network, the LTE network has been commercialized today and it has finally opened a new era that makes it possible for mobile phones to process data at high speed. In LTE network environment, however, a new authentication key must be generated for the hand-over. In this case, there can be a problem that the authentication process conducted by the hand-over incurs its authentication cost and delay time. This essay suggests an efficient key caching hand-over method which simplifies the authentication process: when UE makes hand-over from oMME to nMME, the oMME keeps the authentication key for a period of time, and if it returns to the previous MME within the key's lifetime, the saved key can be re-used.
Development of Indoor Repeater LHCP antenna with Dual Bands
Park, Sung-Il ; Kim, Sun-Il ;
The Journal of The Institute of Internet, Broadcasting and Communication, volume 13, issue 5, 2013, Pages 221~227
DOI : 10.7236/JIIBC.2013.13.5.221
In this paper, Satellite DMB/WiBro antenna and PCS/WiBro antenna improving indoor coverage for mobile services are designed and fabricated. Satellite DMB/WiBro bands repeater antenna and PCS/WiBro bands repeater antenna are proposed as a simple radiator with loading capacitor to generate LHCP(Left Hand Circular Polarization). The proposed antenna for Satellite DMB/WiBro and PCS/WiBro bands communication are fabricated by copper plate uploader type and substrate uploader type. The designed and fabricated antenna has a bandwidth of 70MHz at 1.816GHz~1.886GHz and bandwidth of 107MHz at 2.247GHz~2.354GHz. Maximum gain of radiation pattern was up to 5dBi.
A Study on Analysis and Improvement of Current Korean Army's Mine Detector
Kim, Chi-Wook ;
The Journal of The Institute of Internet, Broadcasting and Communication, volume 13, issue 5, 2013, Pages 229~233
DOI : 10.7236/JIIBC.2013.13.5.229
Mine detector of troops is different from other equipments. It is a base of a miner branch's combat, combat support and mission. But its notion is too obsucure and each troops' model and maker of it is so different and most of it is old type so there are a lot of malfunctions. Hence, I will define management of mine detector and figure out these days miner troops' mine detector situation. I will collect experts' opinions too. Through a discussion we could found improvement plan and develop it adequate for future operational environment. Proceeding all these courses and finally making it weaponize are the points of this writing.
Characteristics of 'ㄷ' type MSA Antenna for Frequency Shift
Park, Sung-Il ;
The Journal of The Institute of Internet, Broadcasting and Communication, volume 13, issue 5, 2013, Pages 235~238
DOI : 10.7236/JIIBC.2013.13.5.235
In this paper, ㄷ-type MSA for the QMSA structure is proposed. Transformed ㄷ-type MSA is stacked three dielectrics. ㄷ-type MSA structure was load upper & lower surface of the dielectric radiating patch and the ground turn-up left right capacity between parallel plates and radiating patch. Between the dielectric permittivity of the dielectric insert by 2.55 by varing the frequency was shifted. Designed ㄷ-type MSA sturcture of L1 was varied up to 1mm~22mm and frequency was shifted from 3.65GHz~3.84GHz. Also Designed ㄷ-type MSA was measured 1.95dBi maximum gain and bandwidth of 1.61 to 3.64%.
Multi-Channel Switching Protocol Using Channel Busy Degree in Ad Hoc Wireless Networks with Multi-Interfaces
Lim, Hunju ; Joung, Sookyoung ; Lee, Sungwha ; Park, Inkap ;
The Journal of The Institute of Internet, Broadcasting and Communication, volume 13, issue 5, 2013, Pages 239~247
DOI : 10.7236/JIIBC.2013.13.5.239
In network based on multi-interface, there are needed channel assignment strategy that reduce interference and improve bandwidth efficiency by assigning each interface to available channels in order to utilize effectively multiple wireless interfaces on each node. MCS protocol had been proposed, which improve capacity and throughput of network by using hybrid assignment. MCS uses as the criterion to assign channel the number of node that use the same channel in contention area. but there have an problem that this information exactly does not reflect actually offered channel load. in this paper, we proposes CAMCS protocol to assign channel by that the channel busy degree to indicate the occupancy rate of channel by nodes as well as the number of nodes that use the same channel in inference area is used as criterion for estimation channel load, and conform performance improvement effect by simulation.
MAC Aware Multi-Channel Routing Protocol for Multi-Interface Ad-Hoc Wireless Networks
Lim, Hunju ; Joung, Sookyoung ; Lee, Sungwha ; Park, Inkap ;
The Journal of The Institute of Internet, Broadcasting and Communication, volume 13, issue 5, 2013, Pages 249~258
DOI : 10.7236/JIIBC.2013.13.5.249
In multi-hop ad hoc networks, multi-interface multi-channel architecture is being noticing as methodology to improve the effective bandwidth and end-to-end throughput, But since existing routing metrics designed for networks based on single-interface exactly can not reflects the nature of networks based on multi-interface multi-channel, we are not expected the effect of throughput improvement. there had been proposal of MCR that discover high throughput by using metrics such as channel diversity and interface switching cost. however, MCR have an problem that is degraded it's performance in congested networks, because it not reflects the impact of traffic load. in this paper, we propose MAMCR metric, which select high throughput paths under congested conditions by combination MCR with channel access time metric, and conform it's the effect of performance improvement by ns-2 simulation.